فهرست مطالب

پژوهش های علوم دامی - سال بیست و هشتم شماره 1 (بهار 1397)
  • سال بیست و هشتم شماره 1 (بهار 1397)
  • تاریخ انتشار: 1397/04/20
  • تعداد عناوین: 14
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  • محمد صدقی، علی طیبی پور، بهجت پورسینا، پریسا سلیمانی رودی * صفحات 1-12
    زمینه مطالعاتی: خوراک مصرفی جوجه های گوشتی هم از لحاظ بهبود عملکرد و هم از لحاظ کاهش هزینه های تولید فاکتور بسیار مهمی در صنعت طیور می باشد.
    هدف
    این مطالعه به منظور ارزیابی جیره های حاوی سطوح مختلف انرژی و اسیدهای آمینه بر عملکرد و ارزش اقتصادی جوجه های گوشتی انجام شد.
    روش کار
    تعداد 1440 قطعه جوجه گوشتی 11 روزه سویه راس 308 به صورت فاکتوریل در قالب یک طرح کاملا تصادفی با 12 تیمار که شامل 3 سطح انرژی (100، 95 و 90٪ احتیاجات توصیه شده راس) و 4 سطح پروتئین و اسیدهای آمینه ضروری (100،105، 95 و 90٪ احتیاجات) استفاده شد.
    نتایج
    بررسی اثرات اصلی نشان داد که استفاده از سطوح مختلف انرژی، تاثیر معنی داری بر مصرف خوراک و افزایش وزن جوجه ها نداشت، در حالی که سطح 90٪ انرژی در جیره، باعث کاهش معنی دار هزینه خوراک به ازای واحد وزن زنده شد. استفاده از سطح 90٪ اسیدهای آمینه به عنوان اثر اصلی در جیره باعث کاهش معنی دار در افزایش وزن روزانه و هزینه خوراک گردید. در رابطه با اثرات متقابل انرژی و اسیدهای آمینه، جوجه های تغذیه شده با جیره های حاوی سطوح 100٪ انرژی و 95٪ اسیدهای آمینه، 95% انرژی و 100% اسیدآمینه و همچنین 95 و 90٪ انرژی و 105٪ اسیدهای آمینه بیشترین افزایش وزن روزانه بدن را دارا بودند. کمترین افزایش وزن بدن و همچنین کمترین هزینه خوراک، مربوط به تیمار دارای سطح 90٪ انرژی و اسیدهای آمینه بود. بین جیره های حاوی 95٪ انرژی و 90٪ اسیدهای آمینه و جیره استاندارد از لحاظ عملکردی اختلاف معنی داری مشاهده نشد. در صورتی که استفاده از جیره با سطوح 95٪ انرژی و 90٪ اسیدآمینه، باعث کاهش معنی دار هزینه خوراک گردید.
    نتیجه گیری نهایی: به طور کلی می توان بیان کرد که استفاده از سطح 95٪ انرژی به همراه سطح 90٪ اسیدهای آمینه، در جیره جوجه های گوشتی از سویی بهترین عملکرد را به دنبال داشت و از سوی دیگر باعث کاهش نسبی در هزینه خوراک گردید.
    کلیدواژگان: اسیدهای آمینه، انرژی، جوجه گوشتی، عملکرد، هزینه خوراک مصرفی
  • ایمان حاج خدادادی *، سجاد عباسی صفحات 13-31
    زمینه مطالعاتی: بررسی استفاده از آنزیم در جیره های رقیق شده بر عملکرد و کیفیت تخم مرغ و قابلیت هضم مواد مغذی مرغ های تخمگذار
    هدف
    در این تحقیق اثر سطوح مختلف آنزیم کمزایم در جیره های رقیق شده، بر عملکرد، کیفیت تخم مرغ و قابلیت هضم مواد مغذی مختلف جیره در اواخر دوره تولید مرغ های تخمگذار سویه هایلاین W36 در دو آزمایش مورد مطالعه قرار گرفت.
    روش کار
    تیمارهای آزمایشی استفاده شده در این آزمایش عبارت بودند از: جیره کنترل (تیمار 1)، جیره رقیق شده (کنترل منفی) (تیمار 2)، جیره رقیق شده همراه با آنزیم به مقدار 25/0 گرم در کیلوگرم (تیمار3) ، جیره رقیق شده همراه با آنزیم به مقدار 50/0 گرم در کیلوگرم (تیمار4) و جیره رقیق شده همراه با آنزیم به مقدار 75/0 گرم در کیلوگرم (تیمار5) و جیره رقیق شده همراه با آنزیم به مقدار 1 گرم در کیلوگرم (تیمار6). در آزمایش اول از 450 قطعه مرغ نژاد لگهورن سویه هایلاین W36 در سن 60 هفتگی (با وزن متوسط 55 ± 1550 گرم) در قالب طرح کاملا تصادفی شامل 5 تیمار با 5 تکرار (18 پرنده در هر تکرار) استفاده گردید. درآزمایش دوم برای تعیین قابلیت هضم از 100 قطعه مرغ نژاد لگهورن سویه هایلاین W36 70 هفته در قالب طرح کاملا تصادفی شامل 5 تیمار با 5 تکرار (4 پرنده در هر تکرار) استفاده شد.
    نتایج
    بررسی مصرف خوراک پرنده ها در طول آزمایش، نشان داد که تفاوت معنی داری (05/0>P) در میانگین خوراک مصرفی پرنده بین تیمارهای آزمایشی وجود داشت. بدین ترتیب نشان داده شد که افزودن 50/0 گرم در کیلوگرم آنزیم به جیره های رقیق شده می تواند عملکرد تولیدی پرنده را تا سطح تیمار کنترل مثبت افزایش داده و حتی در سطوح حاوی سطوح 75/0 و 1 گرم در کیلوگرم، عملکرد بالاتری نسبت به تیمارهای کنترل مثبت و منفی داشته باشد. تیمارهای حاوی حاوی سطوح 75/0 و 1 گرم در کیلوگرم آنزیم، دارای بهینه ترین ضریب تبدیل خوراک بودند. ارتفاع سفیده تخم مرغ، واحد هاو و وزن پوسته تخم مرغ بطور معنی داری در جیره های حاوی آنزیم نسبت به کنترل منفی بهبود یافت (05/0>P). وزن و درصد زرده، درصد سفیده و نسبت سفیده به زرده تخم مرغ تحت تاثیر تیمارهای مختلف آزمایشی قرار نگرفت (05/0P).
    نتیجه گیری نهایی: از بین سطوح آنزیم استفاده شده بر اساس بسیاری از فراسنجه ها بخصوص تولید تخم مرغ، ضریب تبدیل خوراک و قابلیت هضم بسیاری از مواد مغذی جیره سطوح 75/0 و 1 گرم در کیلوگرم آنزیم نتایج بهتری بهمراه داشتند.
    کلیدواژگان: آنزیم کمزایم، عملکرد، مرغ تخمگذار، قابلیت هضم، کیفیت تخم مرغ
  • فرهاد صمدیان *، آرمین توحیدی، محمد امیر کریمی ترشیزی، وحید واحدی صفحات 33-49
    زمینه مطالعاتی:این مطالعه به منظور بررسی اثرات اسانس گیاه دارویی زنیان و زیلپاترول هیدروکلراید روی عملکرد رشد و برخی فراسنجه های خونی مرتبط با تنش سرمایی در جوجه های نر متعلق به خط پدری لاین آرین صورت گرفت.
    روش کار
    در این تحقیق 192 قطعه جوجه گوشتی در قالب طرح کاملا تصادفی با آرایش فاکتوریل 4×2 با هشت تیمار و شش تکرار که هر تکرار شامل 4 جوجه بود، استفاده شد. تیمارهای خوراکی شامل اسانس زنیان در دو سطح 150 و ppm450 و زیلپاترول و برنامه دمایی شامل دمای طبیعی و تنش سرمایی بود. خون‏گیری در روزهای 13، 29 و 36 صورت گرفت.
    نتایج
    افزودن خوراکی ppm150 اسانس زنیان، در دوره رشد افزایش وزن روزانه را نسبت به گروه شاهد کاهش داد (05/0≥P)، ولی اثر معنی‏داری بر ضریب تبدیل خوراک جوجه ها نداشت (05/0P). در بین گروه های تیماری پرورش یافته در تنش سرمایی، دوز بالای اسانس زنیان توانست به طور معنی‏داری موجب تخفیف افزایش مشاهده شده در مقادیر مالون‏دی‏آلدئید پلاسمایی(MDA) و سطوح فعالیت ALT تحریک شده توسط سرما در مقایسه با گروه شاهد سرمایی شود (05/0>P). در بین گروه های تیماری پرورش یافته در محیط طبیعی، زیلپاترول، موجب افزایش سطوح کراتین فسفوکیناز، نسبت T3 به T4 و مقادیر MDA پلاسمایی در مقایسه با گروه «شاهد-برنامه دمایی طبیعی» گردید.
    نتیجه گیری نهایی:اسانس زنیان، به علت اثرات نشان داده شده آنتی‏اکسیدانی و ضد تنشی خود ممکن است در تخفیف اثرات تنش سرمایی موثر باشد.
    کلیدواژگان: جوجه لاین آرین، اسانس زنیان، زیلپاترول هیدروکلراید، تنش سرمایی، شاخص های هماتولوژیکی و بیوشیمی بالینی
  • علیرضا شهدادی، محمدمهدی شریعتی *، محمدرضا نصیری، سعید زره داران، داوودعلی ساقی صفحات 51-64
    زمینه مطالعاتی: طول عمر تولیدی و ماندگاری گاوهای شیری در گله، از مهمترین موضوعات در پرورش گاو شیری می باشد که اخیرا مورد توجه بیشتری قرار می گیرد.
    هدف
    در این مطالعه، از رکوردهای طول عمر و حذف گاوهای هلشتاین ایران برای بررسی دلایل حذف و سازه های موثر بر آن و نیز تعیین تابع توزیع بقاء استفاده شد.
    روش کار
    داده های 971428 راس گاو هلشتاین مربوط به 3872 گله که توسط مرکز اصلاح نژاد و بهبود تولیدات دامی کشور طی سال های 1375 تا 1392 جمع آوری شده بود، استفاده گردید. برای بررسی سازه های موثر بر حذف (فصل زایش، سن هنگام اولین زایش، شکم زایش، مرحله شیردهی و تولید شیر) از رگرسیون لجیستیک و برای تعیین تابع توزیع بقاء از معادله کاپلان - میر استفاده شد. داده ها با استفاده از رویه های lifetest و logistic نرم افزار SAS نسخه 2/9 و R بسته survival تجزیه و تحلیل شدند.
    نتایج
    نتایج نشان داد که ناهنجاری های تولید مثلی شایع ترین دلیل حذف گاوهای هلشتاین (61/23 درصد) بود. سازه های مورد بررسی در این مطالعه تاثیر معنی داری بر خطر حذف گاوهای هلشتاین داشتند (01/0>P). با افزایش شکم و سن هنگام اولین زایش و با کاهش تولید شیر، خطر حذف افزایش یافت. برآوردهای به دست آمده از تابع توزیع بقای کاپلان - میر نشان داد که تا روز 1305 از طول عمر حدود 25 درصد از گاوهای هلشتاین مورد بررسی از گله ها حذف شدند. همچنین 50 و 75 درصد از گاوها به ترتیب دارای طول عمر 2068 و 2942 روز بودند.
    نتیجه گیری نهایی: با توجه به نرخ بالای حذف در گله های کشور، به منظور افزایش طول عمر و بقای گاوهای هلشتاین لازم است که شرایط محیطی و مدیریتی گله ها بهبود یافته و نسبت به کنترل سازه های موثر بر حذف، پیشگیری و درمان بیماری ها اقدام شود. همچنین طراحی برنامه های انتخاب در گاو های شیری بر اساس صفات مربوط به سلامتی، باروری و ورم پستان توصیه می شود.
    کلیدواژگان: طول عمر، حذف، تابع بقاء، گاوهای هلشتاین ایران
  • طاهره مرویی میلان، حسین دقیق کیا *، غلامعلی مقدم صفحات 65-76
    زمینه مطالعاتی :آسیب غشایی به عنوان یکی از دلایل کاهش تحرک و باروری اسپرم خروس مطرح می باشد. تاکنون آنتی اکسیدان های مختلفی جهت کاهش یا جلوگیری از آسیب های غشایی در حین انجماد مورد استفاده قرار گرفته است.
    هدف
    این پژوهش به منظور بررسی اثرات افزودن سطوح مختلف کورکومین (100، 200 و 300 میکرومولار) در رقیق کننده اصلاح شده بلتسویل بر فراسنجه های کیفی اسپرم خروس بعد از یخ گشایی انجام گرفت.
    روش کار
    اسپرم گیری سه بار در هفته از طریق مالش پشتی- شکمی، از 8 خروس بالغ نژاد راس صورت گرفت. نمونه ها پس از ارزیابی اولیه با هم مخلوط شده سپس تیمارهای مختلف اعمال گردید. سردسازی به مدت سه ساعت در دمای 5 درجه سانتی گراد انجام شد. درصد تحرک کل، تحرک پیش رونده و فراسنجه های حرکتی اسپرم با استفاده از سیستم آنالیز کامپیوتری اسپرم CASA و زنده مانی و یکپارچگی غشاء با استفاده از روش رنگ آمیزی ائوزین نیگروزین و آزمون هاست و میزان اسپرم های نابهنجار با استفاده از محیط هانکوک بعد از یخ گشایی اندازه گیری شدند.
    نتایج
    کورکومین در سطح 200 میکرومولار از لحاظ تحرک کل و تحرک پیش رونده توانست بهترین عملکرد را در بین سایر سطوح کورکومین و گروه کنترل داشته باشد و تفاوت معنی داری بین تیمارها مشاهده شد (05/0>p). غلظت 200 میکرومولار کورکومین توانست زنده مانی اسپرم را بهبود بخشد (05/0>p). کورکومین در غلظت 300 میکرومولار بیشترین سلامت غشاء و کمترین ناهنجاری ها را نسبت به بقیه تیمارها داشت و با گروه کنترل تفاوت معنی داری نشان داد (05/0>p).
    نتیجه گیری نهایی: مطالعه حاضر نشان داد افزودن کوروکومین در غلظت 200 میکرومولار می تواند از نظر زنده مانی و فراسنجه های تحرک، اثرات مطلوبی بر اسپرم خروس بعد از فرآیند انجماد- یخ گشایی داشته باشد.
    کلیدواژگان: اسپرم خروس، انجماد، یخ گشایی، آنتی اکسیدان کورکومین، رادیکال های آزاد
  • حسن علی عربی *، نسرین زند، علی اصغر بهاری، مهدی حاجی ولیئی، خلیل زابلی صفحات 77-92
    زمینه مطالعاتی: عنصر آهن در بدن نقش هایی دارد و ممکن است تاثیر انواع منابع آن در جیره غذایی دام متفاوت باشد.
    هدف
    این آزمایش به منظور بررسی اثر دو نوع مکمل آهن (نانو اکسید آهن و سولفات آهن) بر عملکرد و غلظت برخی از عناصر معدنی، هورمون های تیروئیدی و فراسنجه های هماتولوژی در خون بره های در حال رشد انجام شد.
    روش کار
    تعداد 30 راس بره نر مهربان (با میانگین وزن زنده 51/1 ± 10/27 کیلوگرم) در 5 تیمار آزمایشی به مدت 60 روز استفاده شدند. تیمارهای آزمایشی شامل شاهد (فاقد مکمل آهن) و چهار جیره دیگر که به ترتیب مقادیر 25 و 50 میلی گرم در کیلوگرم نانو اکسید آهن یا سولفات آهن به جیره پایه افزوده شده بود. وزن کشی دام ها هر 15 روز یکبار و خونگیری در روزهای 30 و 60 آزمایش انجام شد.
    نتایج
    ماده خشک مصرفی و وزن نهایی در تیمارهای مکمل شده با آهن و میانگین افزایش وزن روزانه در تیمارهای مکمل شده با نانو اکسید آهن به طور معنی داری بیشتر از تیمار شاهد بود (05/0P<). مکمل آهن سبب کاهش معنی دار غلظت مس در روز 60 نمونه گیری و افزایش غلظت آهن پلاسما در هر دو دوره نمونه گیری از خون شد (05/0P<). اما غلظت عناصر روی، کلسیم و فسفر در پلاسما تحت تاثیر مکمل آهن قرار نگرفت. استفاده از مکمل آهن سبب افزایش معنی دار تعداد گلبول های قرمز خون و غلظت هموگلوبین شد (05/0P<). غلظت هورمون های T3 و T4در تیمارهای مکمل شده نیز به طور معنی داری بیشتر از تیمار شاهد بود (05/0P<).
    نتیجه گیری نهایی: نتایج حاصل نشان داد هر چند که استفاده از مکمل آهن سبب بهبود عملکرد بره ها شد، اما بین دو نوع مکمل استفاده شده تفاوت معنی داری در ارتباط با عملکرد و هورمون های تیروئیدی در پایان دوره مشاهده نشد. اما مکمل نانو آهن نسبت به سولفات آهن بر شاخص های هماتولوژی موثر تر بود.
    کلیدواژگان: افزایش وزن، سولفات آهن، گوسفند، نانو اکسید آهن
  • مرتضی خباز سیرجانی، عبدالمنصور طهماسبی، عباسعلی ناصریان، حسن کرمانشاهی، محسن کاظمی، آمنه اسکندری تربقان، الیاس ابراهیمی خرم آبادی صفحات 93-108
    زمینه مطالعاتی: بنتونیت یک ترکیب آلومینوسیلیکاته بوده که در تغذیه نشخوارکنندگان کاربرد فراوان دارد.
    هدف
    آزمایشاتی با هدف بررسی اثر انواع بنتونیت های سدیمی، کلسیمی، فرآوری شده و طبیعی بر غلظت نیتروژن آمونیاکی در شرایط برون تنی انجام شد.
    روش کار
    در آزمایش اول، غلظت نیتروژن آمونیاکی در یک محیط کشت حاوی بنتونیت های فرآوری شده (درصد جرمی اسید سولفوریک به بنتونیت 10، 15 و 20) و طبیعی در زمان های 4 و 24 ساعت انکوباسیون مورد مقایسه قرار گرفت و در آزمایش دوم، اثر اضافه کردن سطوح مختلف بنتونیت سدیم یا کلسیم در زمان های مختلف انکوباسیون بر غلظت نیتروژن آمونیاکی در یک محیط کشت حاوی جیره های غذایی با پروتئین تجزیه پذیری شکمبه ای متفاوت، مورد بررسی قرار گرفت.
    نتایج
    غلظت نیتروژن آمونیاکی پس از 4 ساعت انکوباسیون، تحت تاثیر تیمارها قرار گرفت (05/0>P) به طوری که کمترین غلظت در تیمار 15 درصد و بیشترین مقدار در تیمار 20 درصد مشاهده گردید. در آزمایش دوم غلظت نیتروژن آمونیاکی برای جیره های با پروتئین تجزیه پذیر بالا در زمان های 2 و 4 ساعت انکوباسیون، تحت تاثیر تیمارها قرار گرفت (05/0>P) به طوری که کمترین مقدار در جیره های حاوی 2 درصد بنتونیت سدیم و بیشترین نیز در تیمار شاهد مشاهده گردید. همچنین غلظت نیتروژن آمونیاکی در جیره های با پروتئین تجزیه پذیر کم، تنها در زمان 4 ساعت پس از انکوباسیون تحت تاثیر نوع تیمارها قرار گرفت (05/0>P).
    نتیجه گیری نهایی: نتایج نشان داد غلظت نیتروژن آمونیاکی تحت تاثیر فرآوری بنتونیت و یا نوع بنتونیت سدیمی یا کلسیمی قرار گرفته و بیشترین جذب نیتروژن آمونیاکی در ساعات اولیه انکوباسیون (2 و 4 ساعت) مشاهده گردید.
    کلیدواژگان: نیتروژن آمونیاکی، بنتونیت، برون تنی، انکوباسیون
  • زینب اکبرپناه، همایون فرهنگ فر *، یاسمن شمشیرگران، محمدرضا اصغری صفحات 109-125
    زمینه مطالعاتی: ورم پستان، معمول ترین و از لحاظ اقتصادی، مهم ترین بیماری در صنعت پرورش گاو شیری است که منجر به کاهش تولید شیر، هزینه های درمانی، منع مصرف شیر در خلال درمان، تغییر در سلامت و کیفیت ترکیبات شیر، کاهش زاد و ولد، مرگ و حذف زود هنگام می گردد.
    هدف
    این تحقیق، با هدف برآورد اثر شمار سلول های سوماتیک بر مقدار شیر روزانه در گامه های مختلف شیردهی گاوهای شیری شکم اول حاصل از اسپرم های داخلی و وارداتی انجام شد.
    روش کار
    تعداد 543884 رکورد روز آزمون متعلق به 64634 راس گاو شیری شکم اول در 606 گله که طی سال های 1388 الی 1392 (در ده استان) زایش داشتند، مورد استفاده قرار گرفت. صفت مورد بررسی، شیر روز آزمون بود. رکوردهای شیر روز آزمون، توسط یک مدل خطی آنالیز شدند. مدل مزبور، برای هر ماه به طور جداگانه، بر رکوردهای شیر برازش داده شد.
    نتایج
    بیشترین افت تولید شیر در گاوهای حاصل از اسپرم ایرانی، کانادایی و آمریکایی به ترتیب مربوط به فروردین ماه در گامه ی شیردهی دهم (2430/0 کیلوگرم)، فروردین ماه در گامه ی شیردهی دهم (3853/0 کیلوگرم) و اسفند ماه در گامه ی شیردهی نهم (2305/0 کیلوگرم) بود. کمترین افت تولید شیر در گاوهای حاصل از اسپرم ایرانی، کانادایی و آمریکایی به ترتیب مربوط به دی ماه در گامه ی شیردهی اول (0042/0 کیلوگرم)، آبان ماه در گامه ی شیردهی نهم (0015/0 کیلوگرم) و مرداد ماه در گامه ی شیردهی چهارم (0447/0 کیلوگرم) بود.
    نتیجه گیری نهایی: در گاوهای شیری حاصل از اسپرم ایرانی، آمریکایی، کانادایی، با افزایش شمار سلول های سوماتیک تولید شیر کاهش می یابد و این کاهش تولید شیر ناشی از افزایش شمار سلول های سوماتیک در ده گامه ی شیردهی در ماه های مختلف سال، روند منظمی ندارد.
    کلیدواژگان: رکورد روز آزمون، شمار سلول های سوماتیک، گامه ی شیردهی، گاو شیری
  • سعید احدی، حسن درمانی کوهی *، نوید قوی حسین زاده صفحات 127-139
    زمینه مطالعاتی: به دلیل کمبود داده های در اختیار برای نیازمندی های مواد مغذی در بلدرچین، تخمین پاسخ های بیولوژیکی به مواد مغذی با استفاده از توابع ریاضی توصیف کننده رشد در این گونه دامی مفید به نطر می رسد. علاوه بر این، توابع ریاضی توصیف کننده رشد می تواند یک ابزار سودمند در انالیز نتایج انتخاب ژنتیکی و مشخص کننده تفاوت های بین گروه های ژنتیکی باشد.
    روش کار
    در این آزمایش از تعداد 1050 قطعه جوجه بلدرچین ژاپنی یک روزه به منظور ارزیابی مقایسه ای توابع رشدی ریچارد، لوپز، گمپرتز و ون برتالانفی به منظور توصیف رشد در جوجه بلدرچین های ژاپنی تغذیه شده با جیره های متفاوت در تراکم مواد مغذی استفاده شد. طول دوره پرورش 8 هفته و تیمارهای جیره ای شامل 1) جیره با تراکم 5% کمتر از پیشنهاد جدول احتیاجات غذایی طیور (NRC 1994)، 2) جیره براساس پیشنهاد جدول احتیاجات غذایی طیور، 3) جیره با تراکم 5% بیش از پیشنهاد جدول احتیاجات غذایی طیور و 4) جیره با تراکم 10% بیش از پیشنهاد جدول احتیاجات غذایی طیور، بودند. برازش مدل های با استفاده از Proc NLIN نرم افزار SPSS (SigmaPLot 5.0، 2012) انجام و مدل-ها از نظر کارایی بر اساس آماره هایAIC ،BIC ، RMSE و R2 با هم مقایسه شدند.
    نتایج
    وزن نهایی تخمینی جوجه بلدرچین های تغذیه شده با جیره های با تراکم بالای مواد مغذی در مقایسه با جیره های با تراکم پایین تر بیشتر بود. جوجه بلدرچین های تغذیه شده با جیره های با تراکم مواد مغذی بالاتر در مقایسه با جیره های با تراکم پایین تر در مراحل ابتدایی تر از رشد به نقطه عطف منحنی رسیدند. نکویی برازش مدل های رشدی با استفاده از آماره های مد نظر نشان داد که مدل ریچارد توانایی بهتری را در خصوص توصیف رشد در جوجه بلدرچین ها داشته است که دلیل آن می تواند انعطاف پذیری بیشتر این مدل بوده باشد.
    نتیجه گیری نهایی: به دلیل تاثیر پذیری منحنی های رشدی و پارامترهای تخمینی آن ها از تراکم مواد مغذی تامین شده از طریق جیره، توجه به شرایط تغذیه جوجه بلدرچین ها در زمان استفاده از چنین تخمین هایی به منظور انتخاب و مشخص نمودن تفاوت های ژنتیکی بین گروه ها پیشنهاد می شود.
    کلیدواژگان: بلدرچین ژاپنی، تراکم مواد مغذی، وزن بدن، سن، توابع رشد
  • مرتضی یاری حاج عطالو، رسول پیرمحمدی، یونس علی علی جو، حامد خلیل وندی بهروزیار * صفحات 141-158
    زمینه مطالعاتی: تحقیقات قبلی نشان داده اند عوامل مختلفی مربوط به جیره پایه همانند منبع دانه غلات با توجه به ماهیت متفاوت انواع غلات از نظر میزان و نوع نشاسته، فراهمی نشاسته در بخش های مختلف دستگاه و نوع فرآوری مورد استفاده در ارتباط با دانه غلات، می تواند پاسخ دام به ترکیبات فعال گیاهی را تغییر دهد. با این توصیف، هدف از این مطالعه بررسی اثر نوع دانه غلات در پاسخ بزهای شیری مهابادی به مکمل دانه رازیانه در جیره های غذایی بر زیست سنجه های مختلف متابولیکی است.
    هدف
    این مطالعه به منظور ارزیابی اثرات استفاده از پودر دانه رازیانه همراه با جیره حاوی ذرت یا جو بر عملکرد، قابلیت هضم، تخمیر شکمبه ای و برخی از فراسنجه های خونی بزهای شیری مهابادی در دوره انتقال انجام شد.
    روش کار
    تعداد 24 راس بز آبستن با میانگین سنی 3 سال و 3±65 کیلوگرم وزن در یک آزمایش فاکتوریل 2×2 در قالب طرح کاملا تصادفی به مدت دو ماه از 30 روز مانده به زمان مورد انتظار زایمان تا 30 روز پس از زایش با دو سطح رازیانه (صفر و 10 گرم در روز) و دو نوع غله (ذرت و جو) تغذیه شدند. میزان تغییرات روزانه وزن بدن، تولید شیر روزانه، میزان ماده خشک مصرفی مورد ارزیابی قرار گرفتند.
    نتایج
    افزودن رازیانه موجب افزایش معنی دار مصرف خوراک شد و تغییرات وزن بدن روند کاهشی کمتری را نسبت به گروه شاهد در اوایل شیردهی داشت (05/0P˂). تولید شیر در دام های تغذیه شده با رازیانه نسبت به گروه شاهد افزایش معنی داری داشت و درصد چربی شیر کاهش معنی داری در دام های تغذیه شده با رازیانه داشت (05/0P˂). قابلیت هضم خوراک و اسیدهای چرب فرار کل شکمبه تحت تاثیر تیمار های آزمایشی قرار نگرفت. اما افزودن رازیانه موجب کاهش معنی دار استات و افزایش بوتیرات و پروپیونات شد. غلظت نیتروژن آمونیاکی و جمعیت پروتوزوآیی شکمبه با افزدون رازیانه در جیره، کاهش معنی داری پیدا کرد درحالی که pH شکمبه معنی دار نبود (05/0P˂). در بین فراسنجه های خونی، در دوره بعد از زایش میزان گلوکز خون در دام های تغذیه شده با رازیانه افزایش معنی داری داشت ولی میزان اوره، BHBA و NEFA خون، به طور معنی داری در دام های تغذیه شده با رازیانه کاهش یافت (05/0P˂).
    نتیجه گیری نهایی: افزودن رازیانه در جیره بزهای شیری می تواند موجب بهبود عملکرد و کاهش میزان تعادل منفی انرژی دام در اوایل شیردهی شود.
    کلیدواژگان: تعادل منفی انرژی، داروی گیاهی، آنتول، لیمونن، فنچون
  • فاطمه کاظمی *، تقی قورچی، بهروز دستار، فرشید اشراقی صفحات 159-180
    زمینه مطالعاتی: در پرواربندی گوسفند، جو به عنوان یک غله بومی تنها منبع تامین نشاسته در جیره است؛ اما با توجه به سریع التجزیه بودن نشاسته جو در شکمبه که موجب کاهش pH و بروز اسیدوز و درنتیجه، افت عملکرد دام می شود، جایگزینی این غله با غلات دیگری همانند ذرت که سرعت تجزیه پایین تری دارد، مفید به نظر می رسد.
    هدف
    در این مطالعه اثر جایگزینی جو با انواع ذرت فرآوری شده بر عملکرد، قابلیت هضم خوراک، متابولیت های شکمبه، کیفیت لاشه و سودآوری اقتصادی بره های نر پرواری مورد بررسی قرار گرفت.
    روش کار
    آزمایش در قالب طرح کاملا تصادفی با 7 تیمار شامل: جیره شاهد (100 درصد جو)، 2- 50:50 جو و ذرت آسیاب شده، 3- 100 درصد ذرت آسیاب شده، 4- 50:50 جو و ذرت ورقه شده با بخار، 5- 100درصد ذرت ورقه شده با بخار، 6- 50:50 جو و ذرت پلت شده، 7- 100 درصد ذرت پلت شده انجام شد. به هر تیمار 5 تکرار تعلق گرفت و در کل، 35 راس بره به مدت 84 روز مورد آزمایش قرار گرفتند.
    نتایج
    مقایسات مستقل نشان داد که در دوره های 14، 28، 42 و 56 روزگی تمام تیمارها وزن بالاتری نسبت به تیمار شاهد داشتند (05/0P<). در کل دوره بیشترین میزان ضریب تبدیل غذایی با مقدار 62/8 مربوط به تیمار شاهد و کمترین میزان آن با مقدار 22/6 مربوط به تیمار50% ذرت آسیاب شده بود. تیمار 100 درصد ذرت پلت شده و تیمار شاهد با میانگین 79/1 و 52/1 به ترتیب، بیشترین و کمترین مقدار مصرف ماده خشک را داشتند (05/0P<). همچنین، تیمارها اثری بر وزن لاشه و قابلیت هضم ماده خشک نداشتند، ولی وزن دنبه و نسبت وزن دنبه به لاشه در تیمار 100% ذرت آسیاب شده بیشترین مقدار بود (05/0P<). علاوه بر این، طبق نتایج تحلیل اقتصادی، جیره 100 درصد ذرت آسیاب شده بیشترین میزان تاثیر نسبی بر سودآوری را داشت.
    نتیجه گیری نهایی: نتایج این مطالعه مشخص کرد که استفاده از ذرت در جیره یا جایگزینی 50 درصد از جو با ذرت، می تواند عملکرد رشد و سودآوری بره پرواری را بهبود دهد. همچنین، ذرت پلت شده در بین جیره های حاوی ذرت، می تواند افزایش وزن و ماده خشک مصرفی بیشتری ایجاد نماید.
    کلیدواژگان: جو، ذرت فرآوری شده، سودآوری، عملکرد پروار، گوسفند
  • محمدرضا زرگر، جمال فیاضی *، محمدتقی بیگی نصیری، حسین مرادی شهربابک صفحات 181-194
    زمینه مطالعاتی: باتوجه به اهمیت گاومیش در جهت سازگاری با محیط های خشک، مقاومت در برابر بیماری ها، پایین بودن هزینه های نگهداری و استفاده موثر از مواد خشبی کم ارزش در جهت تولید مواد پروتئینی با ارزش، ارتقا ژنتیکی آن حائز اهمیت فراوانی است.
    هدف
    این تحقیق به منظور یافتن فواصل ژنتیکی گاومیش های مناطق مختلف خوزستان و ارتباط ژنتیکی آنها به کمک آرایه چندشکلی تک نوکلئوتیدی اجرا شد.
    روش کار
    در این مطالعه از تعداد 121 راس گاومیش از گله هایی که تحت پوشش سیستم ثبت مشخصات و رکوردگیری شیر در شهرستان های اهواز، دزفول، شادگان، شوش، شوشتر، دشت آزادگان، کرمانشاهی با منشاء خوزستانی و سایر مناطق بودند، نمونه گیری شد. نمونه ها با استفاده از تراشه ژنومی اختصاصی گاومیش با تعداد 90 هزار نشانگرSNP تعیین ژنوتیپ شدند. سپس جایگاه های با حداقل فراوانی آللی کمتر از 01/0، تعادل هاردی واینبرگ کمتر از 6-10 و نرخ خوانش کمتر از 05/0 کنار گذاشته شدند. داده ها بکمک روش های آماری چند متغییره همچون آنالیز مولفه های اصلی مورد کنکاش قرار گرفتند.
    نتایج
    نتایج آنالیز روابط فیلوژنتیکی نشان داد گاومیش های اهواز بدلیل مرکزیت، متاثر از گاومیش های سایر نقاط استان می باشند، ولی گاومیش های شوشتر و دزفول و دشت آزادگان، نسبت به اهواز اختلاط کمتری دارند. با استفاده از آنالیز مولفه های اصلی نتایج فوق تایید شد. جهت بررسی الگو و ساختار ژنتیکی برای جمعیت های گاومیش استان خوزستان ارزش های FSTبرای هر SNP به روش نااریب تتا محاسبه گردید. بیشترین میانگین ارزش FST بین جمعیت مربوط به گاومیش های شهرستان های دشت آزادگان و شادگان به ترتیب 0159/0 و 0147/0 و کمترین مربوط به شهرستان های اهواز و شوش به ترتیب 0087/0 و 0086/0 بود. آزمون های آماری ژنتیکی جمعیتی و تنوع نژادی نشان داد که در درون جمعیت گاومیش های خوزستانی تنوع ژنتیکی بالایی وجود دارد.
    نتیجه گیری نهایی: نتایج گرافیکی آزمون های خوشه بندی و انتساب حاکی از وجود حداقل 3 زیر جمعیت نسبتا مجزا در گاومیش های خوزستان می باشد. نتایج این تحقیق در مورد تنوع ژنتیکی مشاهده شده در سطح نوکلئوتیدها و فاصله ژنتیکی بین گروه های جمعیتی گاومیش استان، در مطالعات بعدی همچون تشکیل جمعیت پایه گاومیش خوزستان و انتخاب ژنومیکی شایسته توجه هستند.
    کلیدواژگان: آنالیز مولفه های اصلی، پویش کل ژنومی، تنوع تک نوکلئوتیدی، گاومیش خوزستانی
  • لیلا بابادی، مرتضی چاجی *، طاهره محمدآبادی صفحات 195-211
    زمینه مطالعاتی: برهان را شاید بتوان به عنوان منبع غنی از نیتروژن در جیره نشخوارکنندگان استفاده کرد، برهان حاوی الیاف و چربی های اشباع پایین و بدون کلسترول است.
    هدف
    هدف از آزمایش حاضر بررسی امکان جایگزینی گیاه برهان با علوفه یونجه در جیره بزها بود.
    روش کار
    مصرف خوراک، قابلیت هضم مواد مغذی، فعالیت نشخوار، فراسنجه های تخمیری شکمبه، فراسنجه های خونی و جمعیت پروتوزوآی شکمبه بزهای نجدی مورد مطالعه قرار گرفتند. در این آزمایش از 12 راس بز نجدی با میانگین وزن 2±30 کیلوگرم در قالب طرح کاملا تصادفی با سه تیمار و چهار تکرار، استفاده شد. جیره های آزمایشی شامل جایگزینی 50 و 75 درصد برهان با علوفه یونجه و جیره شاهد بدون برهان بودند.
    نتایج
    نتایج نشان داد که پروتئین و چربی خام شاخه کامل برهان نسبت به یونجه بیشتر بود، اما ADFآن کمتر از یونجه بود. غلظت تمام مواد معدنی به جز پتاسیم در برهان بیشتر از یونجه بود. مصرف و قابلیت هضم مواد مغذی (ماده خشک، ماده آلی، NDF، ADF و پروتئین) در جیره های حاوی برهان بیشتر از جیره شاهد بود (05/0>P)، به طوری که جیره حاوی 75 درصد برهان جایگزین شده با علوفه یونجه بالاترین مقادیر را داشت. مدت زمان نشخوار تحت تاثیر جیره های آزمایشی قرار گرفت (05/0>P) و در جیره حاوی 75 درصد برهان جایگزین با علوفه یونجه بالاتر از سایر جیره ها بود. اما مدت زمان نشخوار به ازای مصرف مواد مغذی، جیره های حاوی برهان مقدار کمتری را نشان دادند. غلظت نیتروژن آمونیاکی و pH تحت تاثیر جیره های آزمایش قرار گرفت (05/0P<) و در جیره های حاوی برهان کاهش یافتند. تغذیه برهان به دام ها طی دوره آزمایش، تاثیر معنی داری بر گلوکز و کلسترول نداشت (05/0P>)، اما منجر به کاهش غلظت نیتروژن اوره ای خون شد (05/0>P). جمعیت پروتوزوآی شکمبه بزها تحت تاثیر برهان در جیره به طور معنی داری کاهش یافت (05/0P<).
    نتیجه گیری نهایی: بنابراین نتایج آزمایش حاضر نشان داد که می توان در سطوح پیشنهادی آزمایش حاضر، برهان را بدون اثر منفی بر هضم، تخمیر و متابولیسم در جیره بزها استفاده کرد.
    کلیدواژگان: ترکیب شیمیایی، عناصر معدنی، فعالیت نشخوار، گلوکز خون، نیتروژن اوره ای خون
  • اعظم اسمعیلی نوجه ده، صادق علیجانی *، کریم حسن پور، آرش جوانمرد صفحات 213-228
    زمینه مطالعاتی: مدل رگرسیون تصادفی یکی از دقیق ترین مدل ها برای پیش بینی ارزش اصلاحی، با استفاده از رکوردهای روزآزمون می باشد. با این حال به کار بردن این مدل از نظر محاسباتی دشوار و زمان بر است.
    هدف
    تعیین اهمیت نسبی ارزش های اصلاحی در روزهای مختلف شیردهی و برآورد مولفه های اصلی ژنتیکی برای ارزش های اصلاحی صفات تولید شیر گاوهای هلشتاین ایران اهداف اصلی تحقیق حاضر می باشند.
    روش کار
    از رکوردهای روزآزمون تولید شیر، درصد چربی و درصد پروتئین دوره شیردهی اول گاوهای شیری هلشتاین (متولد سال های 1367 تا 1394) که توسط مرکز اصلاح نژاد کشور جمع آوری شده بود، استفاده شد. برای صفات تولید شیر، درصد چربی و درصد پروتئین به ترتیب از رکوردهای 73839، 65165 و 46881 راس گاو، از 230 گله که در شجره خود دارای 176390 راس گاو بود، استفاده شد. پارامترهای ژنتیکی این صفات با استفاده از مدل رگرسیون تصادفی و توسط GIBSS3F90 برآورد شد. سپس ماتریس همبستگی بین ارزش های اصلاحی به دست آمده در روزهای مختلف شیردهی محاسبه گردید. در ادامه، مولفه های اصلی ژنتیکی از ارزش های اصلاحی توسط رویه PRINCOMP نرم افزار SAS به دست آمد.
    نتایج
    ماتریس همبستگی ژنتیکی بین ارزش های اصلاحی پیش بینی شده در روزهای مختلف نشان می دهد که ارزش های اصلاحی در اواسط دوره شیردهی برای تمامی صفات همبستگی بالایی دارند. با استفاده از تجزیه ی مولفه های اصلی برای ارزش های اصلاحی مشاهده شد که دو مولفه ی اصلی اول درصد بالایی از واریانس ژنتیکی کل را تبیین می کنند. برای صفت تولید شیر اولین مولفه ی اصلی 48/99 درصد و برای صفات درصد چربی و درصد پروتئین به ترتیب 19/98 درصد و 100 درصد از واریانس کل ژنتیکی توسط دو مولفه اصلی اول تبیین شد. نتیجه گیری نهایی: در جهت کاهش هزینه های رکوردبرداری و با در نظر گرفتن همبستگی بالای بین ارزش های اصلاحی به نظر می رسد، پیش بینی ارزش های اصلاحی برای کل روزهای آزمون ضرورتی ندارد. بنابراین می توان روی رکوردبرداری در روزهایی که با مولفه های اصلی ارتباط بالایی نشان می دهند، تمرکز نمود.
    کلیدواژگان: رگرسیون تصادفی، ژنتیک، مولفه اصلی، همبستگی ژنتیکی
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  • M. Sedghi, A. Tayebipour, B. Poursina, P. Soleimain * Pages 1-12
    Introduction
    Poultry industry is growing rapidly throughout the developing countries. There have been a considerable increase in growth rate and feed efficiency in commercial broiler chickens in recent years. The improvement of poultry production highly depends on the synergy between science and practice. By use of modern technology, genetics, microbiology, informatics and nutrition knowledge, production of fattening chicken highly increased in the whole world in last years. Also shorter production period and lower quantity of feed which is needed per kg of weight gain is the main goal of broiler production (Steiner et al. 2008). Poultry feeding is biologically and economically very important factor in broiler production. Feed cost is approximately 65-70% of the total production cost (Esonu et al. 2003). Energy and protein are very important nutrients for formulation of broiler diets. They are determinants in the evaluation of the performance and production coefficients of poultry. Protein and energy having major effect on growth performance of the broiler and they are the most expensive nutrient in broiler diets. Costs are rising along with the development of the poultry industry. Furthermore, there is a limitation on the feed sources which produced in Iran and to prevent loss of nutrients, evaluating the economy of poultry industry is important. Also there are several limiting factors such as environmental conditions which lead to lower weight gain and higher feed conversion ratio as compared to the standard performance in current broiler house in Iran. For these reasons, by feeding chickens with the diluted diets may achieve to the reasonable broiler performance while reducing the production costs. Therefore this experiment was conducted to evaluate the productive and economic performance of broiler chickens fed with different level of energy and digestible amino acids.
    Material and
    Methods
    This study was conducted at the veterinary organization of Khorasan Razavi. A total of 1440 day-old Ross 308 broiler chickens were reared with standard diet during the first ten days of age and then randomly divided into twelve treatment groups. The chickens were arranged as 3×4 factorial completely randomized experimental design according to 3 levels of energy (100, 95 and 90% of Ross 308 recommendation) and 4 levels of protein and essential digestible amino acids (100, 105, 95 and 90% of Ross 308 recommendations). Each treatment considered of 3 replicates of 40 chickens per experimental unit. The birds were reared on the litter pen for 42 days with ad libitum access to feed and water. Experimental diets were formulated to provide similar nutrients content (expect protein, amino acids and energy levels) according to the Ross 308 recommendations. The standard composition and analysis of the diets are given in Table 1. Diets were formulated base on linear programming by using of the UFFDA software. Feed intake (FI) and body weight gain (BWG) were recorded for each period on pen basis, and the data was used to calculate feed conversion ratio (FCR). Mortality was recorded on daily basis, and dead weight recorded to correct FCR. The economic evaluation was performed according to cost of feed intake per kg weight gain; that was calculated as multiplying FCR in cost of each kg diet (Obih and Ekenyem 2010). Data were analyzed using the General Linear Models (GLM) procedure of SAS (SAS, 2003). The differences between the means of groups were separated by Tukey Multiple Range test (P
    Results And Discussion
    In case of energy levels, the main effects showed that, there was no significant difference between FI and BWG, whereas, feed cost per kg final BW was lower in the diet containing 90% energy. These results are in agreement with NRC (1994), which reported that it is not always true to conclude the poultry can adjust feed intake to achieve a minimum energy from diets containing different levels of energy. Similarly, Leeson et al (1996), Nguyen and Bunchasak (2005) and Jafarnejad and Sadegh (2011) found no significant effect on BWG of broiler chicks fed the diets containing different levels of energy. In the study using Hubbard × Hubbard broilers, Aftab (2009) reported that, the diets with the higher energy (2850 kcal) resulted to the lower feed intake and FCR in day 35.
    Broilers fed with the diet containing 90% of amino acids had the lowest BWG and feed cost than those fed with other levels of amino acids. Aftab (2009) reported that with increasing balanced protein from 8.4 to 10.2 g per kg, the FI and BW linearly improved (p
    Conclusion
    The present results demonstrated that balancing diets with 90% of amino acids and 95% of recommendation energy not only decreased feed cost but also partly improved performance of broiler chickens.
    Keywords: Amino acids, Broiler, Energy, Feed cost, Growth performance
  • I. Hajkhodadadi *, S. Abbasi Pages 13-31
    Introduction
    The application of enzymes in poultry diets for the enhancement of nutrient availability and performance had been reported since 1926. Previously, the research conducted on feed enzymes in poultry nutrition focused on non-starch polysaccharide (NSP) degrading enzymes, especially xylanase and β-glucanase, in diets containing wheat, rye and barley (Choct, 2006). The use of unconventional feedstuff for poultry production is however limited due to their fibrousness and inability of birds to possess the cellulase enzyme that can digest the fibre (Kocher et al., 2001). Exogenous enzymes capable of degrading non-starch polysaccharides (NSP) in broiler diets based on cearls grains, including wheat and barley (Bedford and Schulze, 1998), initiated this practice. Researchers found that the use of NSP-degrading enzymes in barley and wheat based broiler diets improved litter quality and performance. The use of NSP-degrading enzymes in wheat and barley based diets for broilers are therefore well established and accepted (Bedford, 1998). Advances in the field of nutrition have made it possible for improvement in the utilization of lesserknown feedstuffs. One of these advances is the use of enzyme technology, which can ameliorate the negative effects of dietary nonstarch polysaccharides in high fiber feed stuffs. Kemin (KYM) is a concentrated multi-enzyme (multi-enzyme complexes are stable assemblies of more than one enzyme, generally involved in sequential catalytic transformation) made from the same organism and fermentation process. It was suggested by the manufacturer that the commercial blend could improve energy metabolism up to 6% and enhance protein utilization up to 2%. Cowieson et al. (2006) observed the nutrient metabolism of broilers fed corn and soybean meal diets was increased by a combination of xylanase, amylase, protease, and phytase so it can be use for efficient digestion of nutrient. As a result of limited published studies evaluating the effect of multi-enzyme preparation on layer hens, this study was conducted to assess the effects of commercial enzyme on production and egg traits and apparent nutrient utilization. The effects of Kemzyme© were evaluated on performance, egg quality and nutrient digestibility in Hy line w36 laying hen at 60 weeks of age.
    Material and
    Methods
    In first experiment was carry outin complete randomized design with 450 layer hen at 60 weeks of age in six tratments as follows; 1- common diet (control), 2-diluent diet 90% of common diet (negative control), 3-diluent diet plus enzyme (0.25 gkg -1), 4-diluent diet plus enzyme (0.50 gkg -1), 5-diluent diet plus enzyme (0.75 gkg -1) 6-diluent diet plus enzyme (1 gkg -1) with five replicate (18 hen in each). Productive performance of hens was recorded for eight weeks and egg quality parameters were measured on the last week of trial. The following data were evaluated: initial body weight, feed intake, and feed to gain. The birds were weighed on the first day of the experiment. Fresh feed was made available daily and the remaining feed was weighed at the end of the week to calculate feed intake and feed to gain. Second experiment, was done with 100 Hy Line W36 layer hen at 70 wks age in same treatment and replicate of experiment one. Four birds from each replicate were selected and placed in clean, disinfected, and steel frame cages equipped with a grid floor and collector tray. Three d of the acclimatization period were allowed prior to the commencement of excreta collection. A known weight (more than enough) of feed was given to each treatment group daily while the total excreta collection was done daily for a period of three. The daily excreta samples for each replicate was weighed, dried and the cumulative samples pooled and used to determine the proximate composition according to AOAC (2000). Diets, excreta samples, were analyzed using the standard methods of the Association of Official Analytical Chemists (AOAC International, 2000). Moisture content as dry matter (DM, AOAC, 2000; 930.15), crude protein (CP, AOAC, 2000; 990; 03), ether extract (EE, AOAC, 2000; 954.02), crude fibre (CF, AOAC, 2000; 978.10), and crude ash (CA, AOAC, 2000; 942.05) of samples was determined in four replications after samples were ground. Digestibility of gross energy, organic matter, dry matter and ether extract was calculated base on marker method.
    Result and
    Discussion
    Enzyme supplementations have significant effect on feed intake, egg production, egg mass, and FCR in the present study. In negative control group that Including diets with 90 percentage of common diet nutrient in the present experiment significantly decreased egg weight but supplementation of this diet with 0.50 gkg -1 enzyme can ameliorate this negative effect. Feed cost, enrgy intake and energy conversion ratio were increased in the hens fed enzyme-included diets compared to hens fed the negative and positive control diet. Protien intake and conversion ratio was improved by enzyme supplementation in diluent diet. Egg quality such as Albumen height, Haugh unit and Egg shell weight were increased in the hens fed enzyme supplemented diets compared to hens fed the negative and positive control diet. There was significant effect of enzyme was detected on digestibility of Gross energy (GE), dry matter (DM), organic matter (OM), (P
    Conclusion
    Generally, the use of Kemin® especially at 0.50 gkg-1 in diet improve performance traits, egg quality and feed intake, nutrient digestibility, and energy in the Hy-line w36 laying hen at late production phase.
    Keywords: Digestibility, Kemzyme, Laying hen, Nutrient, Performance
  • F. Samadian *, A. Towhidi, Ma Karimi, V. Vahedi Pages 33-49
    Introduction
    This study was conducted to determine the effects of dietary supplementation of ajwain essential oil (EO) and Zilmax® (Zilpaterol hydrochloride) on growth performance and some blood parameters associated with cold stress in male chicks belong to paternal line of Arian broiler chickens. Cold environmental temperatures tend to increase blood triiodothyronine (T3) levels, required for the generation of additional metabolic heat to maintain body temperature in colder environments. The subsequent increase in basal metabolic rate results in an increase in oxygen demand and the heart attempts to maintain oxygen supply to the organs and muscles, thus chronically leading to pulmonary hypertension syndrome (PHS), right ventricular hypertrophy, ascites and eventually death (Gupta 2011). According to Currie (1999) the main reasons of the etiology of ascites could be classified as: pulmonary hypertension, cardiac pathologies, and cellular damage due to oxidative stress caused by increased reactive oxygen species (ROS) production. Enkvetchakul et al. (1993) verified that chickens with ascites suffered from high oxidative stress. Therefore, ROS production is increased during hypoxia and ascites (Dawson et al., 1993). As a result of oxidative stress, major antioxidants, such as glutathione, α-tocopherol, and ascorbic acid are reduced in the liver and the lungs of broilers with PHS (Bottje and Wideman 1995). Vitamin E, vitamin C, and other antioxidants have beneficial effects as they scavenge free radicals (Gupta, 2011, Ruiz -Feria, 2009) .
    It has been reported that supplementation of vitamin C (Nemati et al. 2017) in diet of broilers and herbal essential oils as natural antioxidants in the diet of laying hens (Torki et al., 2015) under cold stress conditions resulted improved performance parameters (body weight and feed conversion ratio). Ascites related traits (low red blood cell count, hematocrit, T3, heart weights and high T4) were also improved due to antioxidant (Coenzyme Q10 and vitamin C) supplementation in the diet of broiler chickens (Nemati et al. 2017).
    Various β-adrenergic agonists have been shown to be capable of improving weight gain when added to the feed of various domestic species (Malucelli et al., 1994). Moreover it was eported that, the use of clenbuterol at 0.25 ppm to reduce mortality due to the ascites syndrome in broilers (Ocampu et al. 1998) .We hypothesized that dietary addition of C. copticum and Zilpaterol hydrochloride in chicks diet could attenuate cold stress effects with respect to mortality, serum enzyme activity and plasma levels of thyroid hormones.
    Material and
    Methods
    A total of 196 day-old male chicks were purchased from Babolkenar Arian Line Breeding Center, Babolkenar, Iran. Birds were divided into cold and normal temperature groups after rearing until 13 d. Four dietary treatments (basal diet, dietary addition of ajwain EO at 150 and 450 ppm and zilmax® at 1.6 ppm) each with corresponding replicates (24 replicate; n=192; one male chick in each individual cage as a replicate) were fed to chicks at two different thermal programming environment at the grower phase. At the end of the grower phase, cold thermal program was stopped and ambient temperature became the same and normal through the finisher phase for all chicks. This study was done according to a Complete Randomized Design with 8 treatments. Feed intake (FI) and body weight gain (BWG) were measured at the end of each rearing phase. At the end of experiment (42 days of age), eight birds per treatment were sacrificed, and their RV: TV ratios calculated. At 13, 29 and 36 days of age four birds of each treatment were randomly taken for blood collection from wing vein and the assay of serum Alkaline Phosphatase (ALP), Alanine Transaminase (ALT), Aspartate Aminotransferase (AST) and thyroid hormones levels using commercial kits. Heterophyl to lymphocyte ratio as a measure of stress and hematocrit as a measure of PHS were also assessed in blood samples.
    Results And Discussion
    Dietary addition of 150 ppm ajwain EO decreased body weight gain (P≤0.05) but has no significant effect on feed conversion ratio (FCR) of chicks at growing phase (P>0.05), and did not affect overall performance at the end of the experiment as well. The main effect of cold exposure was significant (P
    Conclusion
    The use of zilpaterol hydrochloride at 0.3 ppm, in the diet did not affect significantly daily weight gain (DWG) and feed conversion ratio (FCR) and had no ascites attenuating effects on paternal line of broiler breeders. Dietary supplementation of ajwain essential also did not affect significantly performance of birds, but may be effective in attenuating cold stress due to its illustrated antioxidant (according to MDA concentration) and anti-stress effects (Decreasing effect on H:L ratio and some enzymatic assays) at the present study. Further research in still required to confirm this hypothesis.
    Keywords: Ajwain essential oil, Cold stress, Hematological indices, clinical biochemistry, Paternal line of commercial broiler, Zilpaterol hydrochloride
  • Ar Shahdadi, Mm Shariati *, Mr Nasiiri, S. Zerehdaran, Da Saghi Pages 51-64
    Introduction
    Reducing of economic lifetime and culling of cow are costly and sophisticatedly process in animal industries (Dohoo et al. 2010). In dairy cattle herds, productive and economic lifetime of cow is important because of their substantial effects on pure benefit of every dairy farm. The productive lifetime is called the interval between calving and culling of cow (Vollema and Groen 1996; Sewalem et al. 2005). Nowadays lifespan is considerably noticed because of increasing of rate culling dairy cattle in most of herds. High culling of dairy cows lead-in few cows get to physical maturity stage and complete production (McCullough and DeLorenzo 1996).
    Recognizing of most important factors affecting culling of dairy cows, longevity performance and economical lifetime and survival distribution function can use for making appropriate breeding strategies in order to improving of longevity and productive lifetime of Iranian Holstein dairy cow. So, the objective of this study was to investigate the culling reasons and factors affecting it and to determine survival distribution function in Iranian Holstein dairy cows.
    Material and
    Methods
    In This study, the records of lifespan and culling of 971428 Holstein dairy cows from 3872 herds during 1996 to 2013 were used. Data were collected by the Animal Breeding Center of Iran. Initial data were edited using R and FoxPro 2.6. In Iranian dairy cattle database, 55 reasons of culling were presented, so we categorized them to 12 general groups. For determination of frequencies of culling reasons, survival package of R program was used (Therneau 2015).
    In this study, season, age at first calving, parity, lactation stage and milk yield as factors affecting culling (independent variables) were investigated. For analyzing of data logistic procedure of SAS 9.2 were used.
    Lifetime of animals was evaluated as number of days from birth to culling or censoring of data. Cows that were not culled at the beginning of the study, as censored records considered and the zero code (0 censor code) was assigned to them. Also, culled animals that having culled code were considered as not censored (1 censor cod). In order to determine survival distribution function in Iranian Holstein dairy cow, lifetest procedure of SAS 9.2 were used. Survival distribution function was calculated by Kaplan-Meier equation (Kaplan and Meier 1958).
    Results And Discussion
    The results of the study showed that reproductive disorders were the most common reason of culling in Holstein dairy cows (23.61%). Reproductive disorders like dystocia, retained placenta and problems related to calving, infertility, repeated abortion and other reproductive disorders are the most typical reason of culling (Ansari-Lari et al. 2012; Aziz Zadeh 2011; Heravi Moussavi et al. 2007). In this study, the second reason of culling were mastitis and problems related to udder (18.18%). When milk production increases, problems related to mastitis, reproductive disorders and health of dairy cow will increase (Abe et al. 2009). The third factor affecting culling was non-economical cow (12.48%).
    The results showed that considered factors (season, age at first calving, parity, lactation stage and milk yield) had significant effect on risk of culling in Holstein cows (P
    Conclusion
    According to the high culling rate in herds, in order to increasing lifespan and longevity of Holstein cows it is necessary to improve environmental conditions and management practices and, to control and manage factors affecting culling, to prevent and treat the diseases. Also, planning of selection programs in dairy cows based on health, fertility and mastitis traits is recommendable.
    Keywords: Lifespan, Culling, Survival function, Iranian Holstein cows
  • T. Marouei, H. Daghigh Kia *, Ga Moghaddam Pages 65-76
    Introduction
    The most worthwhile technique for preservation and management of bird genetic resources is semen cryopreservation, which has been studied in domestic birds like chicken. Despite years of intensive investigations, still more work should be done in order to perform successful cryopreservation of poultry sperm. The lower quality of frozen-thawed poultry sperm and consequently the poor fertilization rates compared to mammalian species are due to the exceptional morphological properties of poultry sperm, which cause freeze damages because of their vulnerable structure to low temperatures. During sperm cryopreservation, it is exposed to cold and osmotic shock, and resulted in increasing oxidation due to raise in oxidative reactions. It reduces sperm motility, viability, and ultimately reduces fertility. Oxidative stress occurs when oxidants are more potent than antioxidants. Hence, increased production of reactive oxygen species (ROS) caused by oxidative stress leads to lipid peroxidation (LPO), apoptosis, and DNA damage. Generally, the most important effect of lipid peroxidation on cells is the disruption of membrane structure and function. Plasma membrane damage is considered as one of the reasons for decreasing motility and fertility of rooster sperm. The aim of this study was to investigate the effects of different levels of curcumin antioxidants (0, 100, 200 and 300 μM) in Beltsville modified diluents for the cryopreservation of rooster semen. The present hypothesis was that curcumin antioxidants would be effective during cryopreserving of rooster sperm. Several parameters such as sperm motility, abnormalities, membrane integrity, viability and abnormality were assessed in this study to find the best level of curcumin antioxidants for cryopreservation of rooster sperm.
    Material and
    Methods
    Semen samples were collected from eight Ross 308 rooster three times a week by massaging along the backbone and abdomen .The criteria in normal quality of sperm was as follows: the volume between 0.2 and 0.6 ml (semen volume was measured visually using a graduated collection tube); the concentration of sperm ≥ 3˟109 sperm/ml (ejaculate concentration was evaluated by haemocytometer); total motility ≥80% and abnormal morphology (Hancock method [17]) ≤ 10%. Then, the semen samples were pooled to remove individual variations and obtain sufficient sperm for analysis. Different levels of curcumin were added to semen samples and followed by freezing. After thawing following sperm parameters were evaluated: total motility (TM, %), progressive motility (PM, %), average path velocity (VAP, μm/s), curvilinear velocity (VCL, μm/s), straight linear velocity (VSL, μm/s), amplitude of lateral head displacement (ALH, μm), beat cross frequency (BCF, Hz), straightness (STR, %), and linearity (LIN, %) using CASA software, viability by Eosin-Nigrosine Staining, membrane integrity by HOST test, and sperm abnormality by Hancock test. .
    Results And Discussion
    The freezing extender supplemented with 200 μM of curcumin resulted in higher percentages of total and progressive motilities in comparison with other groups and control group following the freeze-thawing process (P
    Conclusion
    The results of this study showed that adding 200 μM curcumin can have favorable effects on post-thawed rooster sperm motility parameters, viability, plasma membrane integrity, and abnormality.
    Keywords: Roster sperm, Freeze-thawing, Curcumin antioxidant, Free radical
  • H. Ali Arabi *, N. Zand, Aa Bahari, M. Hajivaliei, Kh Zaboli Pages 77-92
    Introduction
    Iron is one of the essential trace elements for livestock, which is essential for the transport, storage and use of oxygen. Iron is one of the components of hemoglobin, myoglobin, transferrin, cytochromes and many enzymatic systems including catalase, peroxidase, phenylalanine and hydroxylase. Providing iron in the diet improves hematologic parameters and growth performances of calf and lamb. Also, the presence of iron in the diet is necessary for appetite, secretion of thyroid hormones and glucose metabolism. Recently compounds as nanoparticles using nanotechnology have been released. Changes in particle size to the nano-particle (size less than 100 nm) increase surface to volume ratio and change their other characteristics. Increasing the surface area of the nanoparticles allows their interactions with organic and inorganic molecules occur differently. One of these compounds is iron oxide nanoparticle which is used in various industrial fields and even as feed additive. Since the experiments and research on iron nanoparticles have not been carried out in the field of ruminant nutrition, so far this experiment was designed to evaluate the effect of two types of iron (nano iron oxide and iron sulfate) on performance (feed intake and average daily gain), plasma concentration of some minerals, thyroid hormones and hematological parameters of growing Mehraban lambs.
    Material and
    Methods
    In this experiment, 30 male lambs with 4 ± 0.5 months age and average live weight of 27.1 ± 1.51 kg in a completely randomized design were used for 60 days. The lambs were placed indoor in 2×1 meter individual cage with a cement floor and received water and feed individually and ad libitum. The treatments were: 1) basal diet (control), 2) basal diet 25 mg/kg iron as nanoparticles of iron oxide, 3) basal diet 50 mg/kg iron as nanoparticles of iron oxide, 4) basal diet 25 mg/kg iron as ferrous sulfate and 5) basal diet 50 mg/kg iron as ferrous sulfate. Diets were offered to the animals in the morning (8:00) and evening (16:00). In the beginning of the experiment, before morning feeding, lambs were weighed in two consecutive days with 16 hours feed and water deprivation and the average weight of these two days for each animal was considered as weight of day zero. Feed intake on a daily basis in every single lamb was measured. All lambs every 15 days (2 consecutive days) before morning feeding (with a 16-hour feed and water deprivation) were weighed to determine changes in body weight. On days 30 and 60 before the morning feeding, blood samples through the jugular vein were taken from all lambs. Immediately after blood collection, 0.5 ml of heparinized blood was poured into 1.5 ml micro tube and sent to a medical laboratory and using automatic cell counter, hematological parameters (number of red cell, concentration of hemoglobin and red cell percent) were determined. Plasma concentrations of iron, zinc and copper were determined using atomic absorption spectrometry and calcium and phosphorus were determined according to standard methods. Plasma concentrations of thyroid hormones (T3 and T4) were measured based on the immunological competitive enzyme assay using ELISA in accordance with relevant guidelines.
    Results And Discussion
    Dry matter intakes of iron supplemented treatments (treatments 2, 3, 4 and 5( were 1.32, 1.42, 1.36 and 1.39 kg/d, respectively, which were significantly higher than control (1.23 kg/d), (P
    Conclusion
    In overall, the obtained results of this study showed that iron supplementation improved performance, blood iron and thyroid hormones concentrations in lambs. Also blood concentrations of iron and thyroid hormones in all the treatments were within the normal range. However concentrations of above mentioned compounds in control group were in down the ranges and in iron supplemented treatments were in top the ranges. Also no significant difference was observed between the two types of supplements for performance and thyroid hormones at the end of the period. But nano-iron supplement was more effective on hematological indices compared to ferrous sulfate.
    Keywords: Iron sulphate, Nano iron oxide, Sheep, Weight gain
  • M. Khabaz, Ab Tahmasbi, Aa Naserian, H. Kermanshahi, M. Kazemi, A. Eskandari, E. Ebrahimi Pages 93-108
    Introduction
    Bentonite is a combination of aluminosilicate which has a high capacity to adsorb toxins such as aflatoxins and other substances (Magnoli et al. 2010). Many researchers have used this substance as a mineral to control and balance pH of rumen (Bringe and Schultz 1969; Rinsig et al. 1969; Britton et al. 1978). It is identified with a clay composition that 90% of which contains montmorillonite (Aghashahi et al. 2005). It has a high absorption property due to the presence of negative charges on the surface of clay materials (Aghashahi et al. 2005). Bentonite is used for different purposes such as performance improvement of male calves (Aghashahi et al. 2005), reduce radiocaesium contamination of soil (Vandenhove et al. 2005), organic modification for the adsorption of organic contamination (Sreedharan and Sivapullaiah 2012) and improvement the strength properties of dry pellets (Timofeeva and Nikitchenko 2014). The physical and chemical structure of bentonite, allows it to superficially absorb proteins and amino acids (Fenn and Leng 1989). This property of bentonite is hypothesized to protect the proteins and amino acids from microbial fermentation occurring in the rumen. On the other hand, ion exchange attribute makes ammonium ions and cations exchanged (Fenn and Leng 1989) and then, it prompts a more optimized use of rumen microorganisms for microbial protein synthesis, by gradually discharging ammonium ions (Nikkhah et al. 2001). Many commercial bentonites produce in Iran, but their benefits for ruminants is unknown; so, this experiment was conducted to evaluate the effect of sodium, calcium, processed and natural bentonites on ammonia nitrogen concentration using in vitro methods.
    Material and
    Methods
    At the first experiment, ammonia nitrogen concentration was compared in a medium containing natural and processed (mass percent of sulfuric acid to bentonite was 10, 15 and 20) bentonites after 4 and 24 h incubation. The culture medium was prepared according to Menke and Steingass (1988) and Theodorou et al (2001). Ammonia nitrogen concentration was determined according to kjeldahl (Mojtahedi and Danesh Mesgaran 2011). Rumen fluid was collected via fistula of three Baluchi male sheep. Bentonite samples were processed and acivated with sulfuric acid and temperature. Applied feed in this culture medium was composed of ground barley (50%), urea (40%) and processed bentonite (10%). At the second experiment, the effect of adding sodium or calcium bentonite on ammonia nitrogen concentration at different incubation time in a culture containing feed rations with different rumen degradability was investigated. The crude protein was similar between treatments with different ruminal degradability (12.02 vs. 15.15). The culture medium was prepared just as experiment 1 with different feed ingredient (table 1). Bentonite samples were taken from Vivan Company. Sodium bentonite was composed of 69%SiO2, 11.71% Al2O3, 0.04% BaO, 1.56% CaO, 1.99% Fe2O3, 1.13% K2O, 1.82 MgO, 0.04 MnO, 3.08 Na2O, 0.08% P2O5, 1.17 SO3, 0.16 TiO2, 0.01> Cr2O3, 8.22% LOI and calcium bentonite was composed of 64.63%SiO2, 10.02% Al2O3, 0.06% BaO, 4.68% CaO, 2.21% Fe2O3, 0.4% K2O, 1.5 MgO, 0.05 MnO, 2.1 Na2O, 0.08% P2O5, 2.31 SO3, 0.3 TiO2, 0.01> Cr2O3, 11.66% LOI.
    Results And Discussion
    At the first experiment, the ammonia nitrogen concentration was affected by the treatments after 4 h incubation (p
    Conclusion
    Generally, the results indicated that the ammonia nitrogen concentration was affected by the processing procedure of bentonite and sodium or calcium bentonites and the highest ammonia nitrogen absorption was observed at the first incubation times (2 and 4 h). It seems that sodium bentonite compared to calcium bentonite can be more effective in ammonia nitrogen adsorption.
    Keywords: Ammonia nitrogen, Bentonite, In vitro, Incubation
  • Z. Akbarpanah, H. Farhangfar *, Y. Shamshirgaran, Mr Asgari Pages 109-125
    Introduction
    In dairy cattle enterprise, mastitis is a common and economically important disease leading to milk loss, therapeutic cost, changing of milk quality, reproductive problems, animal death, and early culling. A wide range of cow-level and herd-level factors can influence on the number of somatic cell count (SCC) including udder infection, lactation stage, age, breed, short-term of days in milk, season, stress and level of production. This research aimed to estimate the effects of SCC on daily milk yield (DMY) at different lactation stages and months of production of first-parity cows (progeny of internal and external sperms). Variation of DMY in terms of Holstein gene inheritance and first calving age were special objectives.
    Material and
    Methods
    The data used in this research were provided by the Animal Breeding Centre, Karaj, Iran. Data set comprised a total number of 543,884 test day records collected from 64,634 first-parity dairy cows (progeny of 1,899 sires and 56,995 dams) distributed in 606 herds and calved between 2009-2013 (in ten provinces over the country). The trait under consideration (dependent variable) was DMY which is actually a quantitative variable with continuous distribution and measured based on ratio scale. The records were analysed using a linear fixed model. In the model, the effects of province, herd nested within province, year of calving, stage of lactation, sperm type of the sire, two-way interaction between stage of lactation and sperm type, as well as linear covariable of SCC within the two-way interaction, Holstein gene inheritance, and first calving age were taken into consideration. The model was fitted on the test day records of the cows for individual months of production using general linear model procedure of SAS software (Version 9.4) and the effect of SCC was estimated as the partial regression coefficient in 30 combined groups resulted from two-way interaction between stage of lactation and sperm type.
    Results And Discussion
    Most of the partial regression coefficients were statistically significant (P
    Conclusion
    Daily milk yield of Iranian, American and Canadian sperms’ progeny decreases when somatic cell count of their milk increases and that it has no regular pattern at different lactation stages as well as different production months. Holstein gene inheritance and first calving age had positive effect on daily milk yield suggesting that these effects are needed to be taken into account as phenotypic and genetic analyses are carried out. Yearly milk production of daughters of the American sperms are apparently more suffered as compared to the other groups as a result of increasing SCC in DMY.
    Keywords: Dairy cows, Somatic cell count, Stage of lactation, Test day records
  • S. Ahadi, H. Darmani *, N. Ghavi Hossein-Zadeh Pages 127-139
    Introduction
    The Japanese quails are blessed with many desirable characteristics, viz, faster growth, early sexual maturity, high rate of egg production (300 egg/annum), short generation interval (3-4 generations a year), small floor space, less feed requirements (20-25 g/adult bird/day), short incubation period of hatching eggs, less feed cost, and less susceptibility to common chicken diseases (Ernst, 2000). In consequence and due to shortage of available data on nutrient requirements of quails, prediction of biological responses of this type of poultry to nutrients using growth functions seems to be beneficial. Growth modeling are also critical for the understanding and formulation of breeding plans because they shift in response to selection (Marks et al. 1988, Mignon-Grasteau et al. 1999, Aggrey 2003 and Beiki et al. 2011). The representation of biological concepts through the simulation of growth dynamics enables us to better adapt management and nutrition to the requirements of the animals, while taking into account the interaction between genotype, nutrition and environmental conditions [Torres and Ferket 2012]. Eleroğlu et al. (2014) pointed out that the application of mathematical functions to describe the growth of birds was useful in estimating production termination deadline and formulation of appropriate feed mixtures (Michalczuk et al. 2016). Ersoy et al. (2006) claimed the Gompertz and Richards models to be the most appropriate for the characteristics of the growth of chickens, ostriches, turkeys and emus. Conflicting concluding by various authors upon the use of the same functions may result from the use of different genetic groups of birds in experiments. The objective of the present study was 1) to determine the best predictive growth function in describing data from Japanese quails and 2) to investigate the effect of dietary nutrients density on the growth curve parameters estimated by the growth models.
    Material and
    Methods
    One thousand and fifty one-day-old Japanese quails were randomly divided into 4 dietary treatment groups with 3 replicates of 86 quails in each in order to compare four growth functions (Gompertz, Richards, von Bertalanffy and Lopez) for their predicable abilities in describing growth of Japanese quails. The treatment groups were: 1) group with low dietary nutrient density [95% of nutrients recommended by NRC (1994), -5% NRC], 2) group with medium dietary nutrient density [100% of nutrients recommended by NRC (1994)], 3) group with high dietary nutrient density [105% of nutrients recommended by NRC (1994), % NRC] and 4) group with very high dietary nutrient density [110% of nutrients recommended by NRC (1994), % NRC]. Body weights of the birds were measured weekly over the 56 day of the experimental period. Evaluation on the goodness of fit for the models were made by R2, AIC, BIC, and RMSE criteria.
    Results And Discussion
    Evaluation on the goodness of fit for the models using R2, RMSE, AIC, BIC criteria showed advantage for the Richards in describing the growth data of Japanese quails which can be related to the variable point of inflexion in the Richards model and therefore its flexibility. According to the four growth functions considered, estimated final body weights were higher in the high density than the low density diets. The age at point of inflection were earlier in high versus low density diets. As early as 1945, Brody suggested that it was possible to select on the shape of the growth curve. A phenotypic modification of the growth curve was also observed in previous studies. Marks et al. 1988, Mignon-Grasteau et al. (1999), Aggrey 2003 and Beiki et al. (2011) showed that growth curve parameters were heritable. However, data shortage of the nutritional requirement necessary for quail breeding makes the mathematic simulation methods very useful in estimating the biological answer to the food nutrients contribution. The method of mathematic simulation of growth using growth functions can also provide the response of the growth parameters to nutrition (Daren and Marks 1988; Marks 1991; Gebhardt-Henrich and Marks 1993) which has the potential benefits when used for selection.
    Conclusion
    In summary, it was concluded that data regarding the growth parameters of quails would be best interpreted with the use of the Richards model. Meanwhile, since almost all the growth parameters estimated by the models were affected by the dietary nutrients density, therefore special attention needed will be given to the nutrition when selecting the quails as parental for the next generation through parameters estimated by mathematical simulation using growth functions.
    Keywords: Age, Body weight, Growth curves, Japanese quails, Nutrient density
  • M. Yari, R. Pirmohammadi, Ya Alijoo, H. Khalivandi * Pages 141-158
    Introduction
    In the last decades a substantial increase have been done in the research and application of herbal supplements and essential oils as feed additives in ruminant nutrition. One of the main reasons for this trend is to substitute antibiotic growth promoters, which have been completely banned as feed additives in the European Union since 2006 because they are suspected of contributing substantially to increasing resistance among human pathogens. Recent investigations have shown significant antimicrobial effects of several essential oils and essential oil compounds. Also investigations about ruminant nutrition showed a great potential for medicinal plants to be included in daily rations as different plant parts, essential oils or extracts. For centuries, essential oils – defined as natural oils typically obtained by distillation and having the characteristic fragrance of the plant or other source from which they are extracted – have been used around the world for a variety of therapeutic purposes. The ancient Egyptian, Greek, Chinese and other cultures used essential oils in cosmetics, perfumes and medicines. Today, many people use essential oils to enhance their mental, emotional and physical well-being. Mohabadi dairy goats showed a great milking performance as well as high energetic efficiency of milk production. As we know essential oils or medicinal plant extracts have their own problems to ration inclusion such as higher price and lower durability compared with original plant materials. Additionally, powdered pant parts can be easily mixed with the prepared ration without concerns regarding volatility of the core materials. Thus, this experiment was carried out in order to study the effects of fennel seed powder (Foeniculul vulgare) supplementation with two types of diets (based on barley or corn) on performance, rumen fermentation and blood parameters in pre and post-partum Mohabadi dairy goats.
    Material and
    Methods
    Twenty-four Mohabadi dairy goats were used in a completely randomized factorial design (2×2) and received 4 experimental diets including 2 levels of the fennel seed powder (0 and 10 gr/DMI) and two types of cereal grains (corn and barley). Animals were selected based on the parity, previous milk yield, and body weight and parturition time and randomly assigned to the each of the treatments. Animals were in experiment 30 days before to 30 days after the parturition and keep individually. Effects of dietary treatments on daily weight change, milk yield and dry matter intake were assessed as repeated measures data. Also, the effects on milk composition and milk component yield, apparent total tract nutrient digestibility, ruminal fermentation parameters, ruminal volatile fatty acid profile and energy related plasma parameters ante- and post-partum periods were addressed.
    Results And Discussion
    The results of this study showed that fennel supplementation significantly increased dry matter intake and reduced body weight loss in early lactation (P˂0.05), but the grain type did not show a significant effect. Also, milk yield significantly increased and milk fat percentage decreased (P˂0.05) by the Fennel seed supplementation. Nevertheless, fennel seed supplementation did not change daily milk fat, protein, solids and solids nonfat production. Milk production efficiency as calculated based on milk yield per unit of dry matter intake, increased with fennel seed supplementation, may be due to estrogenic and prolactin enhancing effects of the fennel seeds Indeed, the experimental treatments could not significantly change the nutrient digestibility, total VFA concentration and pH. However, the ruminal VFA profile significantly affected by the fennel seed powder. Acetate concentration decreased and butyrate and propionate molar proportions increased with Fennel seed supplementation (P˂0.05). Dietary grain type could not exert a significant effect in ruminal fermentation parameters. Fennel seed powder significantly decreased the ammonia nitrogen concentration and protozoa population. In post-partum period, fennel seed powder supplementation significantly increased blood glucose concentration and decreased plasma urea, BHBA and NEFA (P˂0.05).
    Conclusion
    The results of the present experiment in line with the cited previous researches showed that the fennel seed powder supplementation in the dairy goats diet can improve the production performance and efficiency of early lactating dairy goats. Lowered negative energy balance in early lactating animals, was a result of fennel seed powder supplementation. Based on the present experiment it can concluded that fennel seed powder supplement with corn or barley based diets can improve production efficiency and metabolic profile of ante- and post-partum dairy goats.
    Keywords: Negative energy balance, medicinal plants, Anetol, Limonen, Fenchon
  • F. Kazemi *, T. Ghoorchi, B. Dastyar, F. Eshragi Pages 159-180
    Introduction
    Barley as native cereal is the main source of carbohydrates in fattening sheep in Iran. However, since the starch in barley has higher degradation rate than corn starch, it may cause metabolic disorders such as acidosis and decrease growth performance. Furthermore, the feeding value of a cereal grain is a function of several factors: its nutrient content, different physical and chemical characteristics that influence on digestibility, palatability as it changes feed intake, and associative interactions with the digestive process. In this study, the effect of replacing barley with different processed corn on performance, dry matter digestibility, rumen metabolites and carcass characteristics in Afshari fattening lamb were investigated. On the other hand, change in ration composition has economic and financial effects in addition to the nutritional effect. Decision making about ration composition or changing it ignoring these financial and economic effects, could result in negative consequences. Different ration compositions could simultaneously have different cost and revenue effects and eventually different profitability consequences. So, this study has also tried to investigate all positive and negative economic consequences of replacement barley with different processed corn in fattening lambs.
    Material and
    Methods
    The protocol used in this study was approved by the Animal Ethical Committee at Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran with respect to animal experimentation and care of animals under study. The feeds were formulated according to NRC (1985) recommendations for fattening sheep with equal quantity of energy and protein as 7 treatments including 1) 40% Barley (control) , 2) 20% Grinding Corn, 3) 40% Grinding Corn, 4) 20% Steam Flaking Corn, 5) 40% Steam Flaking Corn, 6) 20% Pelleting Corn and 7) 40% Pelleting Corn (Table 1). Five Afshari ram lambs were allocated to each treatment. The animals kept in a separate pen individually for 84 days (May to July, 2015) in animal research farm of Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran. Growth performance data were analyzed as a completely randomized design using the general linear model (GLM) procedure of SAS software (SAS 2003). The significant differences between treatment means were detected by Tukey-Kramer test at p
    Results And Discussion
    Animals had a daily body weight gain from 167 to 225 gr/day and mean FCR about 8.46. There was no significant difference between dietary treatments for final body weight, daily weight gain, FCR and gross profit (P
    Conclusion
    Replacing barley with processed corn in feed composition of fattening lambs could have some positive consequences. It could improve body gain, feed conversion ratio and dry matter intake that means improve of growth performance. But, its net effect on the profitability depends on the relative price of barley to corn. In this study, in spite of greater market price of corn than barley and then more feed costs, this replacing could improve profitability. Among the corn based rations, the 40% pelleting corn ration created better growth rate compared to the other processed corn.
    Keywords: barley, fattening performance, processed corn, profitability, sheep
  • Mr Zargar, J. Fayazi *, Mt Beigi, H. Moradi Pages 181-194
    Introduction
    The science of phylogenetics, and specially the subfield of molecular systematics, has grown exponentially by amount of publications, general interest and amount of available genetic data. Modern phylogenomic studies use large genomic and transcriptomic resources. however a comprehensive molecular phylogeny of animals, including the newest types of data for all phyla, remains elusive.
    Genome sequences and SNP chips are now accessible for many of species across the animal phylogeny, conveying key features of animal genome evolution into sharper emphasis. The field of animal evolutionary genomics has focused on recognizing the diversity genomic features, rebuilding the history of evolutionary variations in animal genomes and testing hypotheses about the evolutionary relationships of animals. One of the most important buffaloes in Iran are Khuzestani buffaloes, which have a wide distribution. Given the fact that they may be divided into several ecotypes and sub-populations, these may cause problems in genomic wide association study. One of the challenges that always threatens the accuracy of genomic association and genetic variation studies is the existence of sub-populations within the populations. The probable relationship between genetic groups among Khuzestani buffaloes by whole genome markers has not been studied. This study is an effort to understand and provide a detailed insight into the population structure and genomic phylogeny of Khuzestani buffaloes.
    Material and
    Methods
    Blood or hair samples from 121 Khuzestani buffaloes from different regions of Khuzestan province including Ahvaz (n=28), Dezfoul (n=19), Shadegan (n=6), Shosh (n=4), Shushtar (n=9), Dashtazadegan (n=24) and Kermanshah (n=8) samples were collected. The samples were chosen from herds that were registered by Iranian Animal Breeding Center (IABC) and were under milk recording system. DNA of the samples were isolated and sent to Parco Tecnologico Padano in Itally. All samples were genotyped by Axiom@Buffalo 90K bead array of Affymetrix Company. PLINK software was used for pre-processing of raw genotype data based on minor allele frequency (MAF) ≤0.01, Hardy Weinberg disequilibrium (p-value ≤ 10-6) and call rate ≤ 0.05. Thereafter, a total of 64,709 SNPs remaind for the analysis. The genetic distance for each pair of individuals was calculated using R software (ape package). The Neighbor-joining algorithm was used to plot trees based on those distances. Also, the phylogenetic diagram is derived based on the distance matrix and using R software (Phyclust package). To identify the optimal number of clusters, K-means were sequentially increased with K values, and different clustering responses were compared using Bayesian Information Criteria (BIC). FST values (theta) for autosomal chromosomes and counties were calculated by unbiased method. Then, the average genetic distance of each area was calculated with other sampling areas. Principal Component Analysis (PCA) and Discriminant Analysis of Principal Components (DAPC) were performed for genetic clustering of individuals. Adegenet R package was used for PCA and DAPC analysis.
    Results And Discussion
    In our study Unrooted Neighbor-Joining Tree Plot grouped the individuals mainly in one cluster depending on the origin of group or subpopulation. Dezfoul, Shushtar and Dashtazadegan individuals formed their individual clusters and due to genetic relatedness, Ahvaz and Kermanshah clusters were formed almost overlapping with other. Along with the closeness of Dezfoul among themselves, they also showed closeness to Shosh. Kermanshah group lied between Ahvaz, Dashtazadegan and Dezfoul buffaloes.
    Results obtained from DAPC analysis confirmed with those obtained from PCA analysis. Individuals were correctly assigned to their respective clusters. Based on phylogenic result, it is evident that buffaloes of Ahwaz are affected by buffaloes of other province’s regions, because they are in the center. Buffaloes of Shushtar, Dezful and Dasht-E-azadegan have lower emigration rate in comparison with Ahwaz buffaloes. This result also confirmed by principal component analysis. To survey the genomic structure and patterns of Khuzestani buffaloe populations, the Fst values (unbiased Theta) for every SNPs were calculated. This criterion reflects the distribution of diversity between groups and within the group. Its high level indicates that major part of heterozygosity is due to differences in the groups. In other hand, the low level of it, suggests that the diversity is due to the individuals within the group, and the populations or groups are associated. The highest value of Fst was obtained for buffaloes of Dashte-E-azadegan (0.0159) and Shadegan (0.0147) because of its special geographical condition, and the lowest value of Fst was observed for the buffaloes of Ahwaz (0.0087) and Shosh (0.0086). The results of statistical tests of population genetic showed a high genetic diversity in buffaloes of Khuzestan. Graphical view of clustering and assignment test suggested at least three subpopulations for Khuzestani buffaloes. According to the overall results and existence of great SNP diversity, it is possible to move toward construction of base population based on this results.
    Conclusion
    In this study a genome-wide insight into the genomic phylogeny of Khuzestani buffaloes was provided. The results of nucleotide genetic diversity and genetic distance between buffaloes are worthy of attention in subsequent studies such as genomic wide association study, genomic selection and formation of Base populations of Khuzestani buffalo.
    Keywords: Genomic wide study, Khuzestani buffalo, Principal component analysis, SNP diversity
  • L. Babadi, M. Chaji *, T. Mohammadabadi Pages 195-211
    Introduction
    Generally, more than 50% of animal production costs are belong to feeding, since farmers and animal nutritionist are looking for the ways to reduce these costs. Therefore, use native or local plants resources make us closer to this purpose (Patra et al. 2003). Leguminous leaves foliage are used as a high-quality feed resource for livestock (Eryavuz and Dehority 2004). The Albizia lebbeck (siris) may be used as a rich source of nitrogen in the diet of ruminants, this plant contains low fiber, and high minerals, vitamins and saturated fatty acid, and no cholesterol (Patra et al. 2003). This tree is native to tropical regions of Africa and Asia. It is planted in the provinces of Khuzestan, Bushehr, Fars and Hormozgan in Iran. The Albizia lebbeck is a tree with a height of 30 meters in native regions, but in Iran rarely reaches to 12 meters. This tree beginning to flowering is in early of May (Mozafarian 2005). Cyanide, oxalate, saponin and trypsin inhibitors are anti nutrients components of the Albizia lebbeck, and the saponins content of the seeds and pods is more than other sections of the plant (Zia-ul-haq et al. 2013). The Albizia lebbeck inproved the digestibility of dry matter in low quality rations (Lowry 1990). Since Albizia lebbeck is plenty in Khuzestan as tropical climate, and has some anti-nutrients factors, the aim of present experiment was to investigate the possibility of replacing the Albizia lebbeck with alfalfa hay in the diet of goats.
    Material and
    Methods
    In this experiment, the pods and leaves of the Albizia lebbeck were freshly collected from the fields around Mollasani in north of Ahvaz, the capital of Khuzestan, and the farms of the Khuzestan Agricultural Sciences and Natural Resources University, then dried under the shade in open air. Feed intake, nutrient digestibility, rumination, rumen fermentation parameters, blood parameters and rumen protozoan population of Najdi goats were studied. In this experiment, 12 Najdi goats with an average 30±2 kg boby weight were assigned to experimental diets as a completely randomized design with three treatments and 4 replicates for 45 days. The three experimental diets included replacement of 50 and 75% Albizia lebbeck with alfalfa and the control diet without Albizia lebbeck. The diets were formulated according to tables requirements of NRC (2007). Chemical composition of experimental samples including crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), dry matter (DM), acid detergent fiber (ADF), total tannin and some minerals were measured according to the standard methods. The apparent digestibility of nutrients (DM, NDF, and ADF) were measured during 7 days by total collection method for feces, and recording of feed dry matter intake and orts. Chewing activity (eating and rumination time) was visually recorded for 24 h with 5 minute intervals for all goats, then corrected per NDF, DM and ADF intake. Rumen fluid of all goats was collected at the end days of experiment through stomach tubes at 3 h post feeding. pH was measured immediately, and rumen fluid was filtered by four layer of cheesecloth, mixed with 0.2 M hydrochloric acid in equal volume, and stored at -20 ᵒC for measurement of ammonia nitrogen. Blood sampling from all goats was conducted via jugular vein by sterile plastic syringe, at 4 h post feeding. The blood samples were centrifuged (3000 × g, 15 minutes) and plasma removed for subsequent analysis. Glucose, cholesterol, blood urea nitrogen (BUN) measured with laboratory kits (ParsAzmoon) using a spectrophotometer. After collection of rumen fluid, it was mixed with formaldehyde 18.5% for fixation of the protozoa, and they were counted under microscope using hemocytometer lam (Dehority 2003).
    Results And Discussion
    In study of Yusefi et al. (2017), Dwatmadji et al. (1992) and Balogun et al. (1998) the CP in leaves of Albizia lebbeck reported 22.4, 17.50 and 24%, respectively that was near our results (21.4% of DM). In an experiment NDF, ADF and EE of Albizia lebbeck leaves were 46.9, 33.7 and 5.4%, respectively, which was consistence with the results of present study. Our results showed that crude protein and fat of leaves and pods of Albizia lebbeck was more and ADF less than alfalfa hay. The concentration of all minerals, except potassium, in whole branch of Albizia lebbeck were higher than alfalfa hay. Nutrients (DM, OM, NDF, ADF and CP) intake and digestibility in diets containing Albizia lebbeck were more than control diet, and diet containing 75% Albizia lebbeck had highest values. Khy et al. (2012) reported increased in dry matter intake, when added pelleted subabul to diet of swamp buffalo, which fed on paddy straw and concentrate. The Albizia lebbeck in diet of goat increased apparent digestibility of dry matter, CP, NDF and ADF (P
    Conclusions
    Therefore, the results of present experiment showed that at the levels proposed in the present experiment (replacement of 50 and 75% Albizia lebbeck with alfalfa), Albizia lebbeck might be used without any negative effect on digestion, fermentation and metabolism in the diet of goats.
    Keywords: Blood glucose, Blood urea nitrogen, Chemical composition, Minerals, Rumination
  • A Esmaili Nojadeh, S Alijani *, K Hasanpour, A Javanpard Pages 213-228
    Introduction
    In the quantitative genetics area, random regression model is one of the most accurate models for estimating daily breeding value in dairy cattle. However, because of the higher number records per each cow, application of this model is labor and time consuming. In addition, breeding values of cows at different days of lactation are highly correlated. The main objectives of the current study were to determine the relative importance of each breeding value at different days of lactation and to estimate the genetic principal components for the breeding values of Iranian Holstein dairy cattle for milk production traits. Maternal and methods: records of milk production traits of first-parity dairy cows. Milk yield, fat percentage and protein percentage test-day records of 73839, 65165 and 46881 cows, respectively, from 230 herds with 176390 cows in their pedigree were used in the analyses. Only test-day records belonging to 5 to 305 days of lactation were used. The data belonged to cows were born between 1988 and 2015 with age at first calving ranged between 21 to 48 m. In addition, the existence of at least one monthly record in the first 90 days after calving was essential for the cow, otherwise it would be eliminated. These data were collected by National breeding center, Karaj, Iran. Genetic parameters were estimated by a random regression model and Bayesian approach using GIBSS3F90 software. The estimated breeding values at all days of lactation were calculated and standardized using the standard score (z). Then, Correlation matrices among breeding values at different days of lactation and genetic principal components of breeding values were estimated by PROC CORR and PROC PRINCOMP of SAS software, respectively. Finally, we could calculate principal component score as a selection criterion (selection index) for the selection of dairy cattle. For this purpose, the standardized score coefficient was obtained by dividing the daily eigenvector of each principal component by square root of its eigenvalue. The principal component score were calculated of the sum of the multiply between standardized score coefficient and daily standardized breeding values for each cow. However, the principal components could be used as an index to multiple traits evaluation of animals.
    Results and discussion
    The genetic correlations matrix between the estimated breeding values at different days of lactation demonstrated that the breeding values at the middle stage of lactation were highly correlated with the breeding values at the reaming stages of lactation. The genetic principal component analysis revealed that the first two principal components accounted for a high percent of total genetic variance of all studied traits. For milk yield, the first principal component explained 99.48% of genetic variance, while two first components explained almost 98.19% and 100% of genetic variance for fat percent and protein percent traits, respectively. The absolute value of correlations between the first principal component of milk yield and all breeding values (except for day 56 and day 231) were more than 0.056. The absolute values of correlations between the first principal component of fat percent and the daily breeding values were greater than 0.06 for days between 83 and 222; and for protein percent were greater than 0.07 for days 99 to 168 and days 289 to 305.
    Considering the high correlation between breeding values seem to, were estimated breeding values for all days is not required. The first principal component milk yield trait with nearly all estimated breeding values, high correlation and first two principal component fat percent trait of estimated breeding values in the early and middle of lactation period had a high relationship. But first two principal component protein percent trait of estimated breeding values in the middle and later of lactation period had a high correlation.
    Conclusions
    Considering the high cost of recording system in dairy cattle industry and the high correlation between the breeding values, it seems that there is no need to predict the breeding value for all days of lactation. In other words, reducing the number of records per each cow may be beneficial at both economic and genetics stand points. Furthermore, due to the high, direct correlation between the principal components and daily breeding values, the implementation of principal components in the genetic merit evaluation of selection candidates for production-related traits is suggested.
    Keywords: Genetic correlation, Principal component, Random regression