فهرست مطالب

پژوهشهای علوم دامی ایران - سال یازدهم شماره 1 (بهار 1398)
  • سال یازدهم شماره 1 (بهار 1398)
  • تاریخ انتشار: 1398/03/11
  • تعداد عناوین: 10
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  • نسرین مهرداد، یداله چاشنی دل *، اسداله تیموری یانسری، محمد خوروش صفحات 1-15

    امروزه، اهمیت تغذیه کمی و کیفی گوساله ها، برای تحریک مصرف کافی خوراک آغازین به منظور توسعه ی شکمبه و دست یابی به وزن مناسب از شیرگیری در زمان مطلوب و همچنین کاهش هزینه ها مدنظر می باشد. بنابراین، پژوهش حاضر به منظور بررسی اثرات سطوح پروتئین خوراک آغازین و مقدار شیر مصرفی، بر عملکرد و فراسنجه های شکمبه ای در گوساله های نر شیرخوار هلشتاین انجام شد. بدین منظور 40 راس گوساله ی نر تازه متولدشده، به مدت 75 روز مورد پژوهش قرار گرفتند. گوساله ها بعد از 3 روز تغذیه با آغوز، به طور کاملا تصادفی به دو گروه تقسیم شدند. گروه اول 10 درصد وزن بدنشان و گروه دوم 7 درصد وزن بدنشان با شیر تغذیه شدند. این دو گروه دوباره به دو زیرگروه دیگر تقسیم شدند. یک زیرگروه با خوراک آغازین حاوی 17 درصد پروتئین و دیگری با 20 درصد پروتئین تغذیه شدند. دسترسی گوساله ها به خوراک آغازین و آب به صورت آزاد بود. به شیر مصرفی نوبت صبح همه ی گوساله ها، 2 گرم پروبیوتیک شامل: پروبیوتیک باکتریایی (پروتکسین شامل هفت گونه باکتری و دو گونه قارچ) و غیر باکتریایی (مخمر ساکارومایسس سرویزیه) اضافه شد. نمونه گیری از مایع شکمبه، در 30، 60 و 75 روزگی انجام شد. مقدار مصرف خوراک و وزن گوساله ها به ترتیب به صورت روزانه و هفتگی اندازه گیری شد. نتایج نشان داد مصرف خوراک، افزایش وزن روزانه، ضریب تبدیل خوراک، قابلیت هضم ظاهری مواد مغذی و pH مایع شکمبه تحت تاثیر مقدار شیر مصرفی و سطوح پروتئین خوراک قرار نگرفت. مصرف خوراک و افزایش وزن روزانه، به ترتیب در کل دوره و قبل از شیرگیری با افزایش سن افزایش و معنی دار بود. قبل از شیرگیری، ضریب تبدیل خوراک تحت اثر هفته و افزایش وزن بدن گوساله ها تحت اثر روز و اثر متقابل بین روز و سطوح پروتئین خوراک آغازین افزایش یافت. در 30 و 75 روزگی، غلظت نیتروژن آمونیاکی مایع شکمبه به ترتیب تحت تاثیر سطوح پروتئین و اثر متقابل روز و سطوح پروتئین خوراک افزایش و معنی دار بود. در 60 روزگی، غلظت کل اسیدهای چرب فرار، تحت اثر سطوح پروتئین قرار گرفت. نرخ عبور مواد جامد از شکمبه و دستگاه گوارش در بین تیمارها تحت اثر تیمارهای آزمایشی قرار نگرفت. به طورکلی نتایج نشان داد افزایش وزن بدن، قابلیت هضم مواد مغذی و ضریب تبدیل خوراک مصرفی در تیمار 2 (17 درصد پروتئین خام و 10 درصد وزن بدن شیر مصرفی) نسبت به سایر تیمارها از وضعیت بهتری برخوردار بود.

    کلیدواژگان: سطوح پروتئین خوراک آغازین، عملکرد، فراسنجه هایشکمبه ای، گوساله هلشتاین، نرخ عبور
  • حمید فیروزنیا، اکبر تقی زاده *، صادق علیجانی، حمید محمدزاده صفحات 17-26

    مطالعه حاضر به منظور بررسی تاثیر افزودن پروبیوتیک بر تولید، ترکیب شیر و فراسنجه های خونی در گاوهای شیرده هلشتاین انجام شد. به این منظور 12 راس گاو شیرده هلشتاین با متوسط تولید روزانه 3 ± 35 کیلوگرم و روزهای شیردهی 7 ± 110 روز در این آزمایش استفاده شد. تیمارهای آزمایشی شامل: 1- تیمار شاهد (جیره بدون استفاده از پروبیوتیک)، 2- جیره حاوی 6 گرم در روز پروبیوتیک قارچی (مخمر ساکارومایسز سرویسیه) بود. گاوها در جایگاه های انفرادی نگهداری شده و با جیره کاملا مخلوط و در حد اشتها تغذیه شدند. نتایج نشان دادند که افزودن مخمر ساکارومایسز سرویسیه در جیره اثر معنی داری بر مصرف ماده خشک در گاوهای شیری هلشتاین در مقایسه با گروه شاهد نداشت. میزان تولید شیر به طور معنی داری در گاوهای تغذیه شده با مخمر ساکارومایسز سرویسیه در مقایسه با گروه شاهد افزایش یافت. راندمان خوراک تحت تاثیر تیمارهای آزمایشی قرار نگرفت. همچنین، مکمل نمودن مخمر ساکارومایسز سرویسیه درصد چربی شیر را در گاوهای هلشتاین افزایش داد درحالی که درصد پروتئین و لاکتوز شیر تحت تاثیر قرار نگرفت. مکمل نمودن مخمر ساکارومایسز سرویسیه در جیره منجر به افزایش معنی دار گلوکز، کلسترول، کلسیم و فسفر سرم خون و نیز کاهش معنی دار نیتروژن اوره ای خون در گاوهای شیرده هلشتاین شد. همچنین، افزودن مخمر در جیره تمایل به افزایش انسولین، HDL و نیز تمایل به کاهش NEFA در سرم خون گاوهای شیری هلشتاین داشت. درمجموع، نتایج حاکی از آن است که افزودن مخمر ساکارومایسز سرویسیه در جیره باعث بهبود عملکرد گاوهای شیرده هلشتاین شد.

    کلیدواژگان: بالانس انرژی، پروبیوتیک، ساکارومایسز سرویسیه، نیتروژن اوره ای خون، هضم الیاف
  • رقیه رحمانی فیروزی، اسداله تیموری یانسری *، عیسی دیرنده صفحات 27-43

    این پژوهش به منظور بررسی اثرات دو سطح انرژی و پروتئین خام پائین و بالا (به ترتیب مقادیر NRC (2007) و 10 درصد بالاتر از آن) در گامه سوم آبستنی بر وزن بدن، قابلیت هضم ظاهری، فعالیت نشخوار، فراسنجه های شکمبه ای، پروتئین میکروبی و وزن تولد بزغاله با استفاده از 28 راس بز سیستانی (وزن بدن 6/2±25 کیلوگرم، روزهای آبستنی 5±100) در قالب طرح کاملا تصادفی با روش فاکتوریل 2×2 انجام شد. تیمارهای آزمایشی شامل: 1) پروتئین و انرژی پائین 2) پروتئین پائین و انرژی بالا 3) پروتئین پائین و انرژی بالا 4) پروتئین و انرژی بالا. ماده خشک مصرفی و کاهش وزن در زمان زایش در تیمار با پروتئین بالا- انرژی پایین بیشتر بود. اما وزن تولد بزغاله این تیمار به طور معنی داری بالاتر بود. در فراسنجه های خونی 28 روز قبل زایش غلظت کلسترول در تیمار انرژی بالا پروتئین پایین به طور معنی داری افزایش یافت، اما غلظت های خونی گلوکز، تری گلیسرید، اوره و پروتئین کل تفاوت معنی داری نشان ندادند. در 14 روز قبل زایش، غلظت اوره خون در تیمار با پروتئین بالا به طور معنی داری بالاتر بود، اما تفاوت معنی داری در غلظت تری گلیسرید، کلسترول و پروتئین کل خون بین تیمارها وجود نداشت. در 2 ساعت بعد زایش تفاوت معنی داری در غلظت گلوکز و تری گلیسرید بین تیمارها وجود نداشت. تولید پروتئین میکروبی در تیمار با پروتئین بالا- انرژی بالا بیشتر بود. تفاوت معنی داری در فراسنجه های شکمبه ای بین تیمارها مشاهده نشد. به طوری که pH مایع شکمبه قبل از مصرف خوراک در تیمار دارای انرژی بالا و پروتئین پایین نسبت به 3 ساعت بعد از مصرف خوراک بالاتر بود. همچنین غلظت اسیدهای چرب فرار شکمبه با مصرف جیره های حاوی انرژی بالا و پروتئین پایین تر از حد توصیه شده، افزایش یافت. به طورکلی نتایج نشان داد تامین نیاز انرژی و پروتئین در گامه انتهای آبستنی و افزایش سطح پروتئین موجب بهبود عملکرد و افزایش وزن تولد بزغاله در بزهای آبستن می شود.

    کلیدواژگان: انرژی، احتیاجات آبستنی، پروتئین میکروبی، عملکرد
  • مرضیه باقری نسب، فرخ کفیل زاده *، عباسعلی ناصریان صفحات 45-57

    این مطالعه به منظور مقایسه تاثیر استفاده از عصاره برگ بلوط بر عملکرد، وضعیت آنتی اکسیدانی و ترکیب چربی بطنی بره های پرواری با استفاده از 12 بره لری- بختیاری در دو گروه: دریافت کننده جیره بدون عصاره برگ بلوط (شاهد) و گروه دریافت کننده جیره حاوی عصاره برگ بلوط در مدت آزمایشی 105 روز انجام شد. نتایج نشان داد که افزودن عصاره برگ بلوط به جیره تاثیر معنی داری بر عملکرد نداشت، اما موجب کاهش معنی دار چربی بطنی (002/0)، دنبه (026/0) و افزایش وزن روده خالی (003/0) بره ها شد. تفاوت معنی داری بین تیمارها در مورد فراسنجه های خونی مشاهده نشد، درحالی که شاخص آنتی اکسیدانی مالون دی آلدئید با افزودن عصاره برگ بلوط بهبود نشان داد. نیتروژن آمونیاکی شکمبه در بره هایی دریافت کننده عصاره برگ بلوط، به میزان 747/2 میلی گرم در دسی لیتر کمتر بود. اضافه کردن عصاره برگ بلوط موجب افزایش معنی دار به میزان 23/5 درصد در اسید چرب های غیراشباع و کاهش اسید چرب اشباع چربی بطنی گردید. به طورکلی نتایج این تحقیق نشان داد که استفاده از عصاره برگ بلوط (حاوی تانن) در جیره پرواری می تواند موجب بهبود فراسنجه های کیفی لاشه و وضعیت آنتی اکسیدانی بره های پرواری، بدون داشتن اثرات منفی بر عملکرد شود.

    کلیدواژگان: آنتی اکسیدان، بره پرواری، بلوط، تانن، عصاره
  • اشکان صدیقی، علی نوبخت * صفحات 59-72

    تحقیق حاضر به منظور ارزیابی اثرات استفاده از سطوح مختلف مخلوط تفاله های انار، انگور، سیب و لیموترش با و بدون آنزیم بر عملکرد، صفات لاشه، پاسخ ایمنی و مورفولوژی روده در جوجه های گوشتی انجام گرفت. این آزمایش با تعداد 384 قطعه جوجه گوشتی (سویه راس- 308)، در قالب طرح کاملا تصادفی با آرایش فاکتوریل (2×4) با چهار سطح مخلوط تفاله ها (صفر، 2، 4 و 6 درصد)، دو سطح مولتی آنزیم روابیو (صفر و 05/0 درصد) در 8 تیمار، 4 تکرار و 12 قطعه جوجه در هر تکرار، از سن 10 تا 42 روزگی در دو مرحله رشد (11 تا 24 روزگی) و پایانی (25 تا 42 روزگی) انجام گرفت. استفاده از 6 درصد مخلوط تفاله ها و 6 درصد تفاله ها با مولتی آنزیم بدون تاثیر بر ضریب تبدیل خوراک، درصد ماندگاری و هزینه تولید، موجب افزایش مقدار خوراک مصرفی، افزایش وزن روزانه، افزایش وزن نهایی جوجه ها و شاخص تولید شد. 6 درصد مخلوط تفاله ها موجب افزایش معنی دار درصد سنگدان شد. استفاده از مخلوط تفاله ها سطح ایمنوگلوبین G را کاهش داد ولی مولتی آنزیم و مولتی آنزیم با مخلوط تفاله ها اثرات معنی داری بر وضعیت ایمنی جوجه ها نداشت. مخلوط تفاله ها، مولتی آنزیم و مخلوط تفاله ها با مولتی آنزیم اثرات معنی داری بر مورفولوژی روده جوجه ها نداشت. درمجموع استفاده از 6 درصد مخلوط تفاله های انار، انگور، سیب و لیموترش در جیره جوجه های گوشتی نه تنها اثرات منفی بر عملکرد آن ها نداشت، بلکه افزایش وزن روزانه، وزن نهایی جوجه ها و شاخص تولید را نیز بهبود بخشید. درحالی که استفاده از مولتی آنزیم نتوانست کارآیی استفاده از تفاله ها را بهبود دهد.

    کلیدواژگان: آنزیم، جوجه گوشتی، عملکرد، سطح ایمنی، مخلوط تفاله ها
  • اسد کرمی، علی خطیب جو *، محمد اکبری قرائی، کامران طاهرپور، مهدی سلطانی صفحات 73-84

    در آزمایش حاضر تاثیر اسانس هیدروالکلی گیاه داروئی شاه اسپرم (Tanacetum balsamita)، ویتامین های E، C و آنتی بیوتیک ویرجینیامایسین بر عملکرد، متابولیت های سرم، صفات لاشه و جمعیت میکروبی ایلئوم جوجه های گوشتی مورد مقایسه قرار گرفت. تعداد 300 قطعه جوجه گوشتی مخلوط نر و ماده سویه راس-308 در قالب طرح کاملا تصادفی به شش تیمار دارای پنج تکرار و 10 قطعه در هر تکرار اختصاص داده شد. تیمارهای آزمایشی عبارت بودند از: 1) جیره پایه (شاهد)، 2) جیره پایه به علاوه ویرجینیامایسین (200 میلی گرم در کیلوگرم جیره)، 3) جیره پایه به علاوه اسانس هیدروالکلی شاه اسپرم (200 میلی گرم در کیلوگرم جیره)، 4) جیره پایه به علاوه اسانس هیدروالکلی شاه-اسپرم (400 میلی گرم در کیلوگرم جیره)، 5) جیره پایه به علاوه مکمل ویتامین E (400 میلی گرم در کیلوگرم جیره) و 6) جیره پایه به علاوه مکمل ویتامین C (200 میلی گرم در کیلوگرم جیره). خوراک مصرفی، میانگین افزایش وزن، ضریب تبدیل خوراک و شاخص بازدهی تولید اروپائی تحت تاثیر جیره های آزمایشی از 42-1 روزگی قرار نگرفت. رنگ گوشت (روشنی، زردی و قرمزی) ران و سینه، درصد لاشه، ران، سینه و چربی بطنی، درصد چربی و پروتئین گوشت ران و درصد چربی گوشت سینه تحت تاثیر افزودنی ها قرار نگرفتند اما افزودن اسانس شاه اسپرم درصد پروتئین گوشت سینه را کاهش داد. مکمل ویتامین E، غلظت HDL-کلسترول سرم را در مقایسه با جیره شاهد افزایش داد درحالی که غلظت تری گلیسرید، کلسترول کل و LDL-کلسترول سرم تحت تاثیر تیمارهای آزمایشی قرار نگرفتند. ازودن 400 میلی گرم اسانس شاه-اسپرم و ویتامین های E و C جمعیت لاکتوباسیل ایلئوم را افزایش دادند درحالی که اشریشیاکلی تحت تاثیر قرار نگرفت. افزودن اسانس شاه اسپرم تاثیری بر عملکرد و فراسنجه های خونی نداشت اما افزودن 400 میلی گرم اسانس شاه اسپرم به جیره جوجه های گوشتی، سبب افزایش جمعیت لاکتوباسیلوس ایلئومی شد. به طورکلی افزودن اسانس گیاه شاه اسپرم در شرایط عادی پرورش، اقتصادی نیست

    کلیدواژگان: اسانس شاه اسپرم، جمعیت میکروبی، جوجه گوشتی، عملکرد، متابولیت های خونی
  • رضا بهمرام *، مریم اسرافیلی تازه کند محمدیه صفحات 85-95

    در این پژوهش از اطلاعات گوسفندان نژاد کرمانی که طی سال های 1362 تا 1389 در ایستگاه اصلاح نژاد شهر بابک استان کرمان جمع آوری شده بود، برای تجزیه وتحلیل ژنتیکی صفات رشد استفاده شد. صفات موردبررسی شامل افزایش وزن روزانه و نسبت کلیبر در چهار دوره زمانی (تولد تا از شیرگیری، از شیرگیری تا شش ماهگی، شش ماهگی تا نه ماهگی و نه ماهگی تا یک سالگی) بود. اثر ترکیبی گله-سال-فصل (23 گله)، جنس بره و سن مادر هنگام زایش بر تمامی صفات موردمطالعه معنی دار بود. وراثت پذیری مستقیم برای صفات ADG1، ADG2، ADG3، ADG4، KR1، KR2، KR3 و KR4 به ترتیب 14/0، 15/0، 16/0، 16/0، 17/0، 19/0، 20/0 و 23/0 برآورد گردید. وراثت پذیری مادری و واریانس فنوتیپی ناشی از محیط دائمی مادری برای صفات قبل از شیرگیری به ترتیب 11/0 و 03/0 (افزایش وزن روزانه) و 09/0 و 10/0 (نسبت کلیبر) به دست آمد. وراثت پذیری کل صفات موردمطالعه در این پژوهش در دامنه 16/0 تا 23/0 بود. ارزیابی ژنتیکی صفات رشد در این مطالعه نشان داد که ژنتیک مادری بر صفات افزایش وزن روزانه و نسبت کلیبر قبل از شیرگیری نسبت به صفات افزایش وزن و نسبت کلیبر بعد از شیرگیری (از شیرگیری تا شش ماهگی، شش ماهگی تا نه ماهگی و نه ماهگی تا یک سالگی) تاثیر بیشتری داشت. بنابراین به نظر می رسد، برای بهبود ژنتیکی صفات افزایش وزن روزانه و نسبت کلیبر قبل از شیرگیری توجه بیشتر به اثرات مادری ضروری باشد.

    کلیدواژگان: اثرات مادری، ارزیابی ژنتیکی، بهبود ژنتیکی، صفات رشد، وراثت پذیری
  • سمیرا عباسزاده، نصر الله پیرانی *، بهنام احمدی پور صفحات 97-110

    در سال های اخیر به طور عمده مرغان بومی موردتحقیق و توجه بیشتری بوده اند؛ زیرا نقش مهمی در تامین پروتئین حیوانی برای مصرف کنندگان در کشورهای توسعه یافته و درحال توسعه ایفا کرده اند و منابع ژنتیکی پایه برای برنامه های اصلاح نژادی محسوب می شوند. بنابراین شناخت دقیق آن ها می تواند مبنای دقیق تری برای بهبود برنامه های اصلاح نژادی در آینده و استفاده بهینه از منابع موجود در جهت افزایش تولید آن ها گردد. ازاین رو این مطالعه باهدف بررسی الگوی رشد و افزایش وزن جوجه های بومی اصفهان انجام گرفت. بدین منظور از اطلاعات رشد 230 قطعه جوجه بومی از 1 روزگی تا پایان هفته 12 استفاده شد. جوجه ها بعد از توزین در روز اول، شماره گذاری و تا پایان دوره به صورت انفرادی و هفتگی وزن شدند. در پایان هفته های 3، 6، 9 و 12 با استفاده از کولیس دیجیتال طول و قطر ران، طول و عرض سینه و طول و قطر ساق پا اندازه گیری شدند. در پایان هفته 12 کشتار جوجه ها انجام و جنسیت جوجه ها تعیین شد. همچنین وزن لاشه، وزن سینه، وزن ران ها و چربی محوطه بطنی اندازه گیری و موردبررسی قرار گرفت. جهت برازش داده های رشد از سه تابع رشد ریچارد، گمپرتز و لجستیک استفاده شد که به طورکلی برای هر دو جنس نر و ماده، تابع رشد ریچارد با 96/0 r2adj= برازش بهتری بر داده های رشد ارائه داد. نتایج نشان داد که در 2 تا 12 هفتگی وزن زنده جوجه های نر به طور معنی داری بیش تر بود. وزن لاشه و چربی و درصد ران در جوجه های نر و درصد سینه و بال در جوجه های ماده مقادیر بیشتر و تفاوت معنی داری را نشان داد و دو جنس ازنظر درصد لاشه تفاوتی باهم نداشتند. طول و قطر ران در نرها در هفته های 6، 9 و 12 بیشتر از ماده ها و تفاوت معنی داری را نشان داد. طول و عرض سینه در نرها در هفته های 6 و 9 بیشتر از ماده ها بود و تفاوت معنی داری را نشان داد. طول و قطر ساق در همه هفته ها در جنس نر به طور معنی دار بیشتر از جنس ماده بود.

    کلیدواژگان: الگوی رشد، جوجه های بومی، خصوصیات لاشه، وزن بدن
  • سعیده سلیمانی، محمد هادی سخاوتی، علی جوادمنش * صفحات 111-119

    میوستاتین، به عنوان عامل تنظیم کننده منفی رشد ماهیچه های اسکلتی در پستانداران شناخته شده است. ثابت شده است که برخی از جهش های طبیعی موجود در ژن میوستاتین، به علت اثر منفی بر بیان این ژن باعث افزایش رشد و عضلانی شدن گونه هایی مانند گاو، گوسفند، موش و سگ می شود. می توان با استفاده از این الگوهای جهش و استفاده از مهندسی ژنتیک، حیوانات مزرعه ای تراریخت با سرعت رشد بالاتر تولید کرد. در این تحقیق قسمتی از ناحیه 3' UTR ژن میوستاتین، به طول 2180 جفت باز در 15 راس از نژادهای گوسفند دالاق، بلوچی و زل تعیین توالی شد. سپس توالی ها با هدف بررسی وجود جهش ها و همچنین محل هدف ریز RNA ها بررسی و نسبت به ایجاد تغییر in silico در ناحیه تعیین توالی شده برای ایجاد توالی هدف ریز RNA های miR-1 و miR-206 که در سرکوب ژن میوستاتین و افزایش رشد بافت عضله نقش دارند اقدام شد. نتایج تعیین توالی نشان داد که کلیه گوسفندان این مطالعه فاقد جهشی موثر در تغییر بیان ژن میوستاتین بودند. با ایجاد تغییر in silico در دو جایگاه به صورت هدفمند، نسبت به ایجاد دو توالی هدف برای ریز RNA های miR-1 و miR-206 اقدام شد. بررسی بیوانفورماتیکی مشخص کرد که این جهش ها دارای اثرات قابل پیش بینی جانبی نبودند و به همین علت، می توان در آینده از این جهش ها برای دستکاری ژنتیکی با روش ویرایش ژنوم و ایجاد فنوتیپ عضلانی در گوسفندان تراریخت بومی استفاده کرد.

    کلیدواژگان: بافت، عضله، گوسفند، میوستاتین و ریز RNA
  • علیرضا ایوبی، ملک شاکری *، مهدی ژندی، هدایت الله قورچیان صفحات 121-132

    تشخیص سریع آبستنی یکی از فاکتورهای کلیدی موثر در افزایش بازدهی تولید مثل در گاوهای شیری است. گلیکوپروتئین های مرتبط با آبستنی توسط جفت گاوهای آبستن تولید و تراوش می شوند و در سال های اخیر در تشخیص آبستنی گاو مورداستفاده قرارگرفته اند. با توجه به محدود شدن روش سونوگرافی و سایر روش های مورداستفاده به حدود روز 30 پس از تلقیح، هدف از این پژوهش کاهش زمان تشخیص آبستنی با استفاده از نانو کیت تشخیص گلیکوپروتئین مرتبط با آبستنی بود. برای این منظور، یک نانو کیت الایزای ساندویچی برای تشخیص گلیکوپروتئین های مرتبط با آبستنی طراحی و ساخته شد. نانوذرات مگنت به منظور افزایش سطح تماس بین آنتی بادی و آنتی ژن مورداستفاده قرار گرفت و از ویژگی میل اتصال پذیری بالا بین استرپتاویدین و بیوتین برای اتصال آنتی بادی به نانوذرات استفاده شد. در این پژوهش تعداد 58 گاو شیری نژاد هلشتاین انتخاب و تکنیک همزمان سازی و تلقیح مصنوعی انجام شد. نمونه های خون گاوها از روز 18 تا 30 پس از تلقیح روزانه جمع آوری و پس از انتقال به آزمایشگاه نمونه های پلاسمای خون جداسازی شد و وضعیت آبستنی در روز 30 و 60 آبستنی به ترتیب با استفاده از سونوگرافی و لمس راست روده بررسی شد. غلظت گلیکوپروتئین های مرتبط با آبستنی در نمونه های پلاسما با استفاده از نانوکیت اندازه گیری و با استفاده از نرم افزار SAS آنالیز شد. نتایج نشان داد، غلظت گلیکوپروتئین ها از روز 21 تا 30 پس از تلقیح به صورت وابسته به روز در گاوهای آبستن افزایش می یابد. همچنین اولین افزایش چشمگیر در غلظت گلیکوپروتئین ها در روز 23 پس از تلقیح مشاهده شد و گاوهایی که تا روز 60 پس از تلقیح آبستن تشخیص داده شدند، در روز 24 پس از تلقیح غلظت گلیکوپروتئین بیشتری در مقایسه با گاوهای غیرآبستن داشتند (به ترتیب ng/ml 15/0±28/2 و 18/0±7/0) .بر اساس این نتایج، غلظت گلیکوپروتئین در روز 24 آبستنی می تواند نشانه ای زودهنگام از وضعیت آبستنی در گاوهای شیری باشد. بااین حال، مطالعات بیشتری لازم است تا کارایی این روش تایید شود.

    کلیدواژگان: آبستنی، سقط جنین، گاو شیری، گلیکوپروتئین، نانوکیت
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  • Nasrin Mehrdad, Yadollah Chashnidel *, Asadollah Teimori Yansari, Mohammad Khorvash Pages 1-15
    Introduction

     Nowadays, many attempts were made to improve the supply of nutrients to calves and the importance of quality and quantity of calf nutrition, in order to stimulate the adequate consumption of feed for rumen development and achieve to suitable weaning weight at the optimal time and reduce feeding costs has been considered. Therefore, this study was conducted to investigate the effects of levels of starter protein and milk fed on feed intake, digestibility, weight gain and ruminal parameters.

    Materials and Methods

     Forty newborn male Holstein calves (average body weight of 40±2 kg) were used according to a 2×2 factorial experimental design for 75 days. Feeding the colostrum was performed immediately after birth for 3 days. Calves were randomly divided into 2 groups(n=20); first group was fed with whole milk with the amount of 10 % of their body weight (BW), while the second group was fed with whole milk with the amount of 7 % of their BW. These 2 groups were divided into sub-groups of calves (n=10 for each) again. One of these sub-groups was fed with starter diet containing 20 % crude protein (CP), while the other sub-group was fed with starter diet containing 17 % CP ad libitumas the starting feed. The rations were iso-energetic. Water and calf starter were offered free choice. Ruminal fluid samples were collected by esophagus tube after morning feeding on days 30, 60 and 75. Feed intake and calves weight were measured daily and weekly respectively. Statistical analysis was performed using the mixed procedure of SAS software. Treatments means were statistically compared by the test of Duncan.

    Results and Discussion

     The results showed that feed intake, daily weight gain, feed conversion, apparent digestibility of nutrients and ruminal fluid pH was not affected by amount of milk fed and starter protein levels. Although, there were no significant differences between amount of milk fed and protein level of starter on weight gain, but average weight gain was higher in calves fed milk as 10% BW than those fed 7% BW at before weaning. Effect of day was significant on feed intake and daily weight gain at total period and before weaning respectively. Before weaning, the effect of week was significant on feed conversion and the effect of day and interaction between day and starter protein level were significant on daily weight gain. After weaning, feed conversion was not affected by treatments. Interaction between starter protein levels and amount of milk fed were significant for apparent digestibility of dry matter, fat, NDF and ADF. Digestibility of crude protein was not statistically significant between treatments. Amount of feed intake, passage rate of solid materials, rumen microorganisms population can change digestibility of nutrients. Effects of amount of milk fed, starter protein levels and their interactions were not significant on ruminal fluid pH. Rumen ammonia-N concentration was affected by starter protein levels on day 30. But, interaction between day and starter protein level was significant on rumen ammonia-N concentration on day 75. No difference in rumen ammonia-N concentration was observed on day 60. Rumen ammonia-N concentration increased with the starter containing 20% CP. Effect of starter protein levels, amount of milk fed and their interactions on acetic acid and butyric acid concentrations were not significantly different between treatments (P > 0.05). Propionic acid concentration was not significantly different between treatments (P > 0.05). Effect of starter protein levels on the total volatile fatty acid concentration was statistically significant (P < 0.05). Passage rate of solid materials of rumen and the proximal of digestive tract (%/h) were not significantly different among the treatments. Treatment 1 (CP =17% and milk intake = 7% of body weight) and treatment 3 (CP =20% and milk intake = 7% of body weight) had the highest and the lowest solid passage rate in digestive tract. Passage rate of solid materials increased and retention time of solid materials decreased with increased feed intake in calves. Interaction between amount of milk fed and starter protein level was significant on total retention time of solid materials in the digestive tract. Treatment 2 and treatment 1 had the highest and the lowest total retention time of solid materials in the digestive tract and this subject was one of the reasons that caused differences in digestibility of nutrients between treatments.

    Conclusion

    In this study, when amount of milk fed increased, daily weight gain and feed conversion improved and feed intake decreased (numerically). Calf starter containing 20% crude protein had any significant effect difference on performance. Satisfactory growth of young calves from birth to two months of age can be achieved by starter protein level 17% (lower than NRC recommended) if dry matter intake adequate. Calves were fed with whole milk with the amount of 10% of their body weight, their feed intake decreased after weaning. Results showed that, body weight gain, feed conversion, digestibility coefficients of nutrients in treatment 2 was better than other groups.

    Keywords: Starter protein levels, Performance, Ruminal parameters, Holstein calves, Passage rate
  • Hamid Firooznia, Akbar Taghizadeh *, Sadegh Alijani, Hamid Mohammadzadeh Pages 17-26
    Introduction

    The alimentary tract microbial community, is effective on energy efficiency in the host, including energy intake, transport, conversion, and storage. The term “probiotics” has been amended by the FAO/WHO to “Live microorganisms, which, when administered in adequate amounts, cause a health benefit on the host”. Animal nutritionists always try to maximize production efficiency of dairy cattle. Using various additives in animal ration is a common and popular approach to increase yield and production efficiency. Application of antibiotics in diets has proven to be effective tools for improve energy retention and reduce nutrient losses in ruminant animals. However, many countries concern regarding use of antibiotics in animal feed industry. Then, researchers try to find other non-antibiotic alternatives to manipulate rumen fermentation in order to reduce energy and nutrient losses and improve nutritional value of diets. In the last years, use of direct-fed microbial as a feed supplements have been studied in many countries around the world. Saccharomyces cerevisiae is a commonly used direct-fed microbial supplementation in dairy cattle ration. Although improve in milk production, milk fat synthesis, rumen pH, ratio of propionate to acetate and fiber digestibility has been seen in some experiments, However, dairy cattle have been shown different responses to Saccharomyces cerevisiae supplementation in their feed. Then, the current study was carried out to evaluate the effect of probiotic (Saccharomyces cerevisiae) on milk yield and composition, feed intake, production efficiency and blood parameters of high producing multiparous Holstein lactating cows.

    Materials and Methods

     Twelve multiparous Holstein dairy cows with average daily yield of 35 kg and 110 days in milk were used in this study. Experimental period length was 28 days including 21 d for adaptation period and the last 7 d for sample taking and data recording. Dietary treatments consisted of 1) control (ration without probiotic) and 2) diet containing 6 g/d probiotic (Saccharomyces cerevisiae) that fed as ad libitum. Diets were equal in terms of protein, net energy for lactation and neutral detergent fiber. During experimental period, milk yield was recorded on d 14, 21 and 28 of trial and were sampled to evaluate milk composition such as protein, fat, and lactose using milkoscan set. Feeds and orts were weighed daily from d 21 to 28 to determine the feed intake of animals. To assess biochemical blood parameters, each cow was bled via vein 2 hours after morning feeding at the last day of trial. Blood samples then were centrifuged at 4 ºC and 1850×g for 20 minutes. Then, serum was analyzed for glucose, insulin, calcium, phosphorus, urea nitrogen, high density lipoprotein, low density lipoprotein, cholesterol, triglyceride and non-esterified fatty acids using kits. Data were analyzed as a completely randomized design using the MIXED procedure of SAS.

    Results and Discussion

     Results showed that dietary inclusion of yeast (Saccharomyces cerevisiae) had no effect on dry matter intake of animals as compared to control group. However, dry matter intake was numerically higher in animals fed Saccharomyces cerevisiae due to acceleration in fiber digestion and consequently higher passage rate. Milk yield was increased (P<0.01) in cows fed Saccharomyces cerevisiae when compared to control group. Moreover, feed efficiency was not affected by dietary treatments. Similarly, supplementation of 6 g/d Saccharomyces cerevisiae noticeably increased (P<0.01) milk fat percentage and tended to decrease (P=0.06) milk urea nitrogen concentration due to lower blood urea nitrogen in this group. However, milk protein and lactose percentage were not affected by inclusion of 6 g/f Saccharomyces cerevisiae in diet. Furthermore, dietary supplementation of Saccharomyces cerevisiae led to an increase in blood serum glucose (P<0.01), cholesterol (P<0.05), calcium (P<0.01) and phosphorus (P<0.01) concentration and a decrease in blood urea nitrogen (P<0.05) concentration in Holstein lactating cows. Also, dietary inclusion of Saccharomyces cerevisiae tended to increase blood serum insulin (P=0.08) and high density lipoprotein (P=0.05) concentration and tended to decrease non-esterified fatty acids (P=0.06) concentration in dairy Holstein cows.

    Conclusion

     In general, results of this experiment indicated that dietary inclusion of 6 g/d of Saccharomyces cerevisiae caused an improvement in milk yield and milk composition of dairy Holstein cows. Moreover, improvement in blood glucose, high density lipoprotein, cholesterol, calcium and phosphorus concentration and reduction in non-esterified fatty acids in response to Saccharomyces cerevisiae might lead to better reproduction performance and prevention some metabolic disease (e.g. ketosis and fatty liver) of high producing dairy cattle.

    Keywords: Blood Urea Nitrogen, Energy Balance, Fiber Digestion, Probiotic, Saccharomyces cerevisiae
  • Roghayeh Rahmani Firozi, Asadollah Teimouri Yansari *, Essa Dirandeh Pages 27-43
    Introduction

    Nutrient requirements of goats have not been studied as extensively as those of beef and dairy cattle and sheep. Furthermore, Sistani goats have received less research attention than meat or dairy goats. Goats play an important role in Iran, largely as a source of red meat and milk. Iran has 25 million goats and kids. Results of research on ruminants showed that nutrients can affect prenatal growth if the lack of nutrition during gestation (in utero nutrition) will affect the postnatal growth performance. Dietary nutrient, especially energy and protein, are major factors affecting meat production in goats. During the late gestation, the last two months of pregnancy, eighty percent of the fetal growth occurs, leading to a significant increase in nutrient requirements of the ewe. Underfeeding energy or protein during pregnancy can lead to pregnancy toxemia, sub ketosis, or compromised fetal development, especially at the end of pregnancy when fetal growth rate is highest. The idea of using levels energy and protein in Sistani goat is new Therefore, this experiment conducted to test the effect energy and protein on on performance, digestibility, microbial protein, some of metabolites and ruminal parameters in late pregnancy of goat.

    Materials and Methods

     The experiment was conducted in the Sari Agricultural Sciences and Natural Resources University (SANRU) of Iran. Humane animal care and handling procedures were followed according to the University’s animal care committee. On 100 days after successful matting, 28 synchronized singleton pregnant Sistani goats (with 3-year-old; body weight = 25±1.6 kg, and body condition score =2.6±0.5) were randomly allocated to four treatments and fed with experimental rations including 1) low protein and low energy diets (LPLE), 2) high protein and low energy (HPLE), 3) low protein and high energy (LPHE), and 4) high protein and high energy (HPHE). Feeds and rations samples were dried at 55°C, ground through a Wiley mill (1-mm screen), and composted by animal. Samples were analyzed for DM, OM, Kjeldahl N, ether extract (AOAC, 2002), ADF, NDF (Van Soest et al., 1991; using heat resistance alpha amylase without sodium sulphate), and ash at 605°C. The NFC was calculated by 100- (CP (%) + NDF (%) + Ash (%) + EE (%). The goats were weighted at the start of experiment, before and1 d after parturition, and Kids weight after birth. Nutrient digestibility, blood parameter, microbial protein synthesis and chewing activity. By measuring urine purine bases microbial protein synthesis was estimated. Rumination and chewing activity animal were measured visually with five-minute intervals over 24 h for all animals. Rumen fluid was collected at o h before feeding and at 3h post feeding. The sample were sealed and placed in freezer before transport to the laboratory for the analysis the NH3 and VFA content.

    Results and Discussion

     Our results showed that the intake of nutrients was increased in HPHE Treatment. Treatment HPLE had highest apparent digestibility than other experimental treatments. Goats on the higher CP diet lost more BW at parturition than other treatments. The lowest pH occurred at 3h post feeding. The ph of rumen fluid after the food ration is provided tends to decrease gradually because of fermentation in the rumen, particularly that of carbohydrates, which are degraded into VFA products. The VFA production increased at 3 h post feeding. There were no differences for microbial protein synthesis but had increase in treatment HPHE for microbial protein synthesis. Concentration of plasma cholesterol was significantly difference at 28d before generation. Glucose concentrations and urea were increased in HPLE treatments and Concentration of plasma triglycerid was lower in goats fed LPLE diet at 14d before generation. Glucose plasma concentration was higher in HPHE than other groups at 2h after generation. The birth live weight of kids was similar between the four groups but LPLE, LPHE and HPHE had numerically lower birth weight. The HPLE group had greatest and LPLE group had lowest body condition score.

    Conclusion

     Overall, these results show that maternal protein feeding during late gestation has been positively associated with kid birth weight and performance. In this experiment, 10 % of CP concentration greater than NRC (2007) recommendation, increased the body weights kids and improved performance of goat. Although, it seems that further experiments are needed.

    Keywords: Energy, protein, pregnancy, microbial crude protein, performance
  • Marzieh Bagherinasab, Farokh Kafilzadeh *, Abbas Ali Naserian Pages 45-57
    Introduction

     Most dietary recommendations have advocated for limitation of saturated fatty acids (SFAs) in food for the optimal management of cardiovascular diseases and cancer. Many evidences exist on the effects of saturated FA consumption on vascular function, insulin resistance, diabetes, stroke and cancer. Therefore, improvement of saturated fatty acids to polyunsaturated fatty acids (PUFAs) during meat production is required. Nutritionists have focused on the change of type of FA by feeding ruminants with the plant oils, which are rich in PUFAs. Plant oils in the form of whole seeds might have less adverse effects on rumen fermentation than in the form of free oils. Among all oil seeds, canola has a unique FA profile. The PUFAs are excellent targets for free radical attacks beginning peroxidation. The direct antioxidant activity of a dietary compound would assume its absorption along the gastrointestinal tract and its deposition in the tissues. Several natural compounds have been demonstrated to have clear antioxidant effects in vitro experiments and animal tissues. Among these, natural polyphenol compounds have largely been studied for their strong antioxidant capacities. Because of these antioxidant properties they inhibit lipid peroxidation and peroxygenases. Monomeric phenolic can be absorbed through the intestine and found in plasma. Tannins (hydrolysable and condensed tannin) are water soluble polyphenolic polymers that are found in a wide range of plant species commonly consumed by ruminants. Oak leaves are widely used as source of fodder for goats and sheep. Oak leaves have been reported to contain high levels of tannins in both hydrolysable and condensed forms. The objectives of the present study were to determine the influence of addition of oak leaf extract to a diet containing canola seed on performance, blood parameters, antioxidant status and fatty acid composition of omental fat.

    Materials and Methods

     Twelve lambs were randomly divided into two groups and kept individually for 105 days. Lambs were fed diet either with or without oak leaf extract. Diet contained 70% concentrate and 30% alfalfa hay. Ruminal fluid was at collected 4h after feeding in the final week of the experiment. Lambs were slaughtered after 105 days of finishing period. Following chilling the carcass, carcass components were determined and a sample of omental fat was taken from the pelvic area for fatty acid analysis. The fatty acids were determined using a direct method for fatty acid methyl ester synthesis using a gas chromatograph. The plasma overall antioxidant status, malondialdehyde concentration and other blood parameters were measured. Data were analyzed as a completely randomized design using the General Linear Model procedure of SAS.

    Result and Discussion

     The results of this study showed that addition of oak leaf extract had no significant effects on animal performance, dry matter intake, blood biochemical profile and ruminal parameters. Fat tail and omental fat as a proportion of cold carcass weight were decreased while empty intestine weight increased when oak leaf extract was fed. Addition of oak leaf extract significantly (P< 0.05) decreased plasma malondialdehyde although total antioxidant capacity was unaffected by diet. Supplementations of oak leaf extract increased mono and polyunsaturated fatty acids and decreased saturated fatty acids of omental fat. Oak leaf extract might inhibit lipid peroxidation and increase antioxidant enzymes activities and decrease malondialdehyde in plasma. Diets enriched with natural antioxidants protect cells and tissues from lipoperoxidative damage. Oak leaf extract may have modulated biohydrogenation of rumen fermentation hence fatty acid profile of omental fat. The plant extract containing polyphenols influence rumen biohydrogeation by altering rumen microorganisms. Changes in ruminal microbial community, indeed direct interaction of tannins with the enzymes responsible for biohydrogenation, affects the last step of the biohydrogenation process and changes the intermediate products resulting in increasing the production of C18: t11 and CLA in rumen and finally increasing PUFA in tissues. Reduction of lipid levels in carcass of lambs received the extract might be due to the anti-lipogenic effect of tannic acid in oak leaf extract.

    Conclusion

    Addition of oak leaf extract to the diet containing canola seed decreased fat tail and abdominal fat in carcass and improved antioxidant status of animals. The results confirm the influence of the tannins on lambs’ carcass composition. Further research is needed to examine the effect of different doses of oak leaf extract on rumen microbial population particularly those involved in biohydrogenation process of fatty acids in the rumen.

    Keywords: Carcass fatty acid profile, Finishing lamb, Oak leaf extract, Tannins
  • Ashkan Sedighi, Ali Nobakht * Pages 59-72
    Introduction

    The agro-industrial processing was resulted some wastes as vegetable and fruit by-products. The fruit byproducts use as energy sources in animal feed and using of these by-products are economically and environmentally sound way for food processors to reduce waste discharges and cut waste management cost. Selling by-products can also produce additional revenue. The poor state of economy in developing countries has made consumption of high protein foods out of reach of more than 65-70% of the people. One of the ways of solving this problem is use unconventional sources of feed ingredients to supplement the diets of man and farm animals. Fruit pulps are some of these unconventional feedstuffs. Pulps contain some of essential nutrients and secondary substances those can be use as feed ingredients in poultry diets. As pulps contain highly amount of undesirable compounds such as crude fiber and pectin, that poultry digestive tract cannot tolerate highly amount of them, imagine that adding effective feed enzyme can be solve this problem. In the current study the effects of different levels of pomegranate, grape, apple and lemon pulps mixture with and without multi-enzyme on performance, carcass traits, immune response and intestinal morphology of broilers was evaluated.

    Materials and Methods

    This experiment was conducted with 384 Ross- 308 broilers in a completely randomized design as factorial arrangement (4*2) with 4 levels of pulps mixture (0, 2, 4, 6%) and 2 levels of Rovabio multi-enzyme (0, 0.05%) in 8 treatments, 4 replicates and 12 chicken in per replicate from 10 up 42 days in grower (11-24 days) and finisher (25-42 days).

    Results and Discussion

    Using 6% of pulps mixture and 6% of pulps mixture with 0.05% of multi- enzyme without having any significant effects on feed conversion ratio, livability and feed cost, increased the amounts of feed intake, weight gain, final live weight and production index (P<0.05). Using 6% pulps mixture significantly increased the percentage of gizzard (P<0.05). Multi- enzyme and pulps mixtures with multi-enzyme had not affect the carcass traits of broilers (P>0.05). By using pulps mixture, the level of IgG decreased (P<0.05) but pulps mixture with multi-enzyme had not significantly affect the immune level of broilers (P>0.05). Pulps mixture and multi-enzyme had not any significant effects on intestinal morphology of broilers (P>0.05). Increase in the amount of daily feed intake by using 6% of pulps mixture may be related to high amount of diet fiber. Fiber increase the speed of feed passing through digestive tract, by this way the amount of feed intake increased. By increasing the amount of feed intake, the amount of nutrient supplying increased and the amount of daily weight gain improved. As improving of weight gain was obtained by feeding highly amount of feed intake, for this reason feed conversion ratio not significantly improved. Improve of final weight and production index by using 6% of pulps mixture may be related to highly amount of daily weight gain. Increase of gizzard percentage maybe related to the amount of diet fiber. As fiber increased the volume of diet, it can increase the gizzard size. Pulps contain some active antioxidant compounds such as flavonoids, isoflavones, flavones, anthocyanins, coumarins. It thought that these compounds can increase the immune level of chickens, but this condition in the current study not occurred. It can be have some reasons such as kinds and levels of pulps in mixture, the quality and processing of pulps, the health status of broilers and diets ingredients. Pulps contains some actives that these actives can change the intestinal morphology, but this change not occurred in the current study, it may be related to the amount of each pulp in pulps mixture, length of experiment period and experiment starting time. Adding enzyme to the diets did not have any significant effects on performance and other parameters of broilers. It can have some reasons such as the amount and composition of multi-enzyme, quality of multi-enzyme, mixing time of diets, diets other ingredients and bird health.

    Conclusion

    The overall results of the present study showed that in broiler chickens using 6% pomegranate, grape, apple and lemon pulps mixture without having any significant effects on intestinal morphology, can improve their performance, final live weight and production index. Using multi-enzyme could not improve the efficacy of pulps mixtures in broiler diets.

    Keywords: Broilers, Enzyme, Immune level, Performance, Pulps mixture
  • Asad Karami, Ali Khatibjoo *, Mohammad Akbari Gharaei, Kamran Taherpour, Mahdi Soltani Pages 73-84
    Introduction

     Antibiotics as growth promoters in poultry feed are posing serious health risks to human health. Because of their residual effects in poultry meat and eggs, and pathogens developing resistance to antibiotics. Currently, poultry scientists are challenged to find out alternatives to antibiotic growth promoters with no side effects for poultry that could be more or as effective against harmful microorganisms in the gastrointestinal tract and to stimulate the growth by increasing the efficiency of feed utilization and to enhance the immunity. Regarding to this subject, supplementing the dietary herbs or plant extracts would stimulate the productive performance of poultry. Tanacetum balsamita contains various has a rich secondary metabolite with diverse biological and therapeutical activities. These compounds consist of essential oil or volatile oil (monoterpenes and sesquiterpens), phenylpropane derivatives, flavonoids (Flavonols, apigenine derivatives, scutellareine derivatives and luteoline derivatives), tannins and oligo-elements that has antioxidant effects on poultry. Its powder or watery or ethanolic extract influenced broiler or laying hen performance and blood metabolites. In all of the reports, researchers used only powder or extract not essential oil and hence there was not any comparison between this plant with antibiotics and some antioxidant vitamins. The aim of this study was the comparison between Tanacetum balsamita essential oil with antibiotics and vitamin E and C as synthetic antioxidants on broiler chicken performance and blood metabolites.

    Materials and Methods

     Three hundred Ross-308 broilers from 1 to 42 days of age were used in a completely randomized design in 6 treatments and 4 replicates and 10 birds in each. The dietary treatments consisted of: 1) basal diet as control group, 2) basal diet supplemented with 200 mg/kg Tanacetum balsamita essential oil, 3) basal diet supplemented with 400 mg/kg Tanacetum balsamita essential oil, 4) basal diet supplemented with 200 mg/kg Vitamin E, 5) basal diet supplemented with 200 mg/kg vitamin C and 6) basal diet supplemented with 200 mg/kg virginiamycine antibiotic. Tanacetum balsamita essential oil extraction was done by Giah-Essanse Company in Golestan Province. The diets were formulated to meet the requirements of broilers as established by the Ross 308 broilers feeding guide in starter (1-12 d), grower (11-25 d) and finisher (26-42 d). The birds were kept under conventional conditions for vaccination, temperature, ventilation, and lighting based on Ross 308 catalogue recommendations. Standard management practices of commercial broiler production were applied. The broiler diets were formulated based on standardized ileal digestible amino acids and other requirements were obtained from Ross catalogue recommendations. Broiler chicken performance (feed intake, body weight gain, feed conversion efficiency and European production efficiency factor), blood metabolites like (triglyceride, total cholesterol, HDL and LDL Cholesterol) and carcass and abdominal fat percentage were calculated. Breast and tight meat fat and protein percentage and color (based on L, a, b scale as brightness, yellowness and redness respectively) were detected. Finally, population of Lactobacillus and Escherichia coli of ileum were detected.

    Results and Discussion

     The results showed that feed intake, body weight gain, feed conversion ratio and European production efficiency factor (EPEF) were not significantly affected by dietary treatments. Chickens received diet containing vitamin E had higher HDL-cholesterol concentrations compared to control and other dietary additives (P < 0.05) while triglyceride, total cholesterol and LDL-cholesterol did not influence by experimental treatments. Thigh and breast meat Color (brightness, yellowness and redness), fat and protein percentage, carcass and abdominal fat of thigh meat and protein percentage of breast meat were not affected by additive while addition of Tanacetum balsamita essential oil significantly reduced the protein percentage of breast meat (P < 0.05). Chickens received diet containing 400 mg/kg Tanacetum balsamita essential oil and E and C vitamins had a higher ileal lactobacillus population than control group (P < 0.05). However, there was an increase in the number of E. Coli in ileum of chickens fed diets containing Tanacetum balsamita essential oils was not significantly different with that of control birds.

    Conclusio

    In conclusion, supplementation of Tanacetum balsamita essential oil had no effect on growth performance and carcass parameters and blood metabolites of broiler chickens while higher level of Tanacetum balsamita essential oil increased of Lactobacillus population. This experiment was done in a common condition without any challenge and antioxidants such as vitamin E and C or some essential oils may affect broiler chicken performance during some challenge. It is suggested that it may be beneficial if this herb or its essential oils added to broiler chicken diet with some challenges like heat and cold stresses.

    Keywords: Blood Metabolites, Broiler, Microbial Population, Performance, Tanacetum balsamita
  • Reza Behmaram *, Maryam Esrafili Taze Kand Mohamaddiyeh Pages 85-95
    Introduction

    Kermani sheep is one of the native dual purpose breeds that adapted with Kerman province’s climate conditions. Body weight traits for sheep meat producers are very important, therefore precise evaluation of genetic factors for these traits have always been concern of breeders. Regarding to importance of meat production in economic benefit of sheep farming, this research was done with goal of genetic parameters estimation for daily gain and Kleiber ratios in Kermani sheep.

    Materials and Methods

     This research was done by using pedigree information form 10988 Kermani sheep between 1983 to 2010 that was collected by Kermani sheep breeding station located in Shahr-e- Babak city of Kerman province, for genetic analysis of growth traits. Studied traits were average daily gain from birth to form weaning (ADG1), form weaning to 6 months (ADG2), form 6 months to 9 months (ADG3), form 9 months to 1 yearling (ADG4) and Kleiber ratios corresponding to the respective daily weight gain (KR1, KR2, KR3 and KR4). For data preparation and edition, pedigree analysis and genetic analysis of studied traits Excel, Fox Pro, CFC and Wombat Softwares were used respectively. Test of significance for the fixed effects on studied traits was done by GLM procedure of SAS 9.2 Software and significant level of p<0.05 was considered for fitting fixed effects in final model. Combined effect of HYS (23 herds), lamb sex and dam age at lambing was significant for all of studied traits. Genetic analysis of traits was performed of restricted maximum likelihood method by using of Wombat and most appropriate model according to Akaike’s information criterion was selected.

    Results and Discussion

     In this research the records number of growth traits decreased by age due to culling of some of lambs or not registering of records in higher ages. The average daily gain of pre-weaning was calculated 231.77 gr and this trait for post-weaning periods had down trend that was complied with reported results in similar studies. Average of ADG1 in this research rather than reported amounts by other researches was more that represented high capacity of growth in Kermani lambs. The Average of ADG2, ADG3, ADG4, KR1, KR2, KR3 and KR4 were estimated 109.98, 40.78, 38.06, 19.86, 13.13, 7.63 and 3.30 gr respectively. The various climate conditions like raining content and environment temperature affects the quality and quantity of forage that resulted in significant changes at available nutrients amount of animal and supply of requirements and consequence of it the daily gain of lambs at different ages. Male lambs in all of traits compare with female lambs were more that showed that effect of sex on Kermani sheep lambs. The average of single lambs was more than twin lambs. The effect of dam age at lambing was significant on all of studied traits. The direct heritability for ADG1, ADG2, ADG3, ADG4, KR1, KR2, KR3 and KR4 were calculated 0.14, 0.15, 0.16, 0.16, 0.17, 0.19, 0.20 and 0.23 respectively. Although direct heritability of ADG1 was low, but by increasing of age the amount of direct heritability for traits increased that may be caused to the reducing effect of maternal effect on studied traits with increasing age. The total heritability for ADG1, ADG2, ADG3, ADG4, KR1, KR2, KR3 and KR4 were estimated 0.19, 0.20, 0.19, 0.16, 0.21, 0.19, 0.23 and 0.23 respectively. The covariance for ADG3 was estimated negative that shows negative presence of maternal genetic effects in this traits heritability and selection response. The genetic correlations between ADG1-KR1, ADG2-KR2, ADG3-KR3 and ADG4-KR4 were estimated 0.57, 0.74, 0.68 and 0.54 respectively. The phenotypic correlation between ADG1-KR1, ADG2-KR2, ADG3-KR3 and ADG4-KR4 were 0.84, 0.89, 0.88 and 0.98 respectively. It seems that selection for Kleiber ratio in each period resulted in increasing daily gain at that period too. Therefore, by selection according to Kleiber ratio, the average of food efficiency will increase. Between environmental correlation of studied traits with direct correlation of them showed that the difference among them was low in most of cases. Thus, regarding to available information it seems that the univariate model was more appropriate in genetic evaluation of studied traits.

    Conclusion

     The results of this research showed that selection according to Kleiber ratio in Kermani sheep can increase the efficiency of feed intake. More than this, the Kleiber ratio has this advantage that at calculating, starter and finisher weights of period which estimation of them are simple.

    Keywords: Genetic evaluation, Genetic improvement, Growth traits, Heritability, Maternal effects
  • Samira Abbaszadeh, Nasroliah Pirany *, Behnam Ahmadipour Pages 97-110
    Introduction

    Native chickens are playing an important role in rural economy in most of the developing and underdeveloped countries. One of the sources that provides protein in developing countries, is native chicken. So, they should be taken in to consideration in poultry improvement programs. Mathematical functions called ‘growth functions’ have been used to relate body weight to age or cumulative feed intake. Growth models summarize information needed to understand the biological phenomenon of growth; an important component in livestock production systems. They are used to determine the age-live weight relationship of animals and each its own characteristics and mathematical limitation.
    Little is known about the productive performance of native chickens, so the objective of the present study was to characterize growth performance and growth curve of Isfahan native chickens under a confined system.

    Materials and Methods

     The chickens of this study included 230 of Isfahan native chickens which were reared for 12 weeks. The birds were raised under the same condition in the rearing period. Feed and water were provided ad libitum. Temperature and air humidity in the hall were measured and controlled automatically day and night. The average temperature was 25°C (max 32°, min 18°) and air humidity was 60-65%. During raising period, chickens were vaccinated and dewormed following the sanitary program of the region. The lighting program consisted of 24 h from 1 day to 12 weeks of age. At 1-day of age, each chick was weighed and marked with color plastic tags attached on the on the right leg. The chickens were individually weighed weekly until the end of the experiment. Some morphometric traits were measured at weeks 3, 6, 9 and 12. Morphometric traits were included breast width, breast length, thigh diameter, thigh length, shank diameter and shank length. Those measurements were done on day 84 with the help of a field assistant, so the birds each time were held in comfortable position and measurements taken in particular order for above mentioned times for accuracy. The chickens were slaughtered and after determining their sex, divided into economics parts. The carcass traits evaluated included live-weight at 12 weeks of age, carcass weight, carcass yield, and primal cuts (breast, thighs, wings and back and neck) weight. Flexible growth and fixed point of inflection functions were evaluated for their ability to describe the relationship between live-weight and age. For Three non-linear growth functions (Gompertz, Logestic and Richard), were used for this purpose. The accuracy of the used functions was determined by determination coefficient (R2), root mean square error (RMSE) and Akaike’s information criterion (AIC). Statistical analysis of data collected in this study was performed using the SAS statistical program v9.1.

    Results and Discussion

     Based on goodness of fit criteria and statistical analysis, the flexible growth functions fit the data better than the functions with a fixed point of inflection. Richard’s function gave the best fit to the data with r2adj= 0.96 for both sexes. The results indicated that male broilers had a higher final body weight than the female broilers. Sex had significant influence on live weight from the second week until the last week and no significant influence on live weight of first week. Chicken sex had significant influence on carcass and abdominal fat weight, yields of thighs, breast and wings and no significant influence on carcass yield. Male chickens were found to have higher live body weight, carcass weight, yields of thighs, whereas yields of breast and wings were higher in female chickens. Breast width of males in every week numerically was higher than females, but this difference was statistically significant at weeks of 6 and 9. Length of the breast at weeks 6, 9 and 12 was significantly higher than females. Thigh diameter of males numerically was higher than females but this difference was statistically significant at weeks 6, 9 and 12 only. Length and diameter of the shank in males was significantly higher than females in each week.

    Conclusion

     The male chickens had superior growth performance and higher potential for selection and breeding. Comparison of tree growth functions in terms of goodness of fit criteria revealed that the Richard’s function was the most appropriate function for describing the age-related changes in body weight of native chickens. Special attention should be paid to characterization of the growth pattern of birds under different environmental conditions. The development of growth curves for native chickens may be useful in selecting chickens that have rapid growth at early ages.

    Keywords: Body weight, Carcass characteristics, Growth function, Native chickens
  • Saeedeh Soleimani, Mohammad Hadi Sekhavati, Ali Javadmannesh * Pages 111-119
    Introduction

    Myostatin, known as the growth and differentiation factor 8 (GDF8), is a negative regulator of skeletal muscle growth in mammals. This gene is conserved across mammalian species and expressed in developing as well as mature skeletal muscles fiber cells. It has been demonstrated that a natural mutation in myostatin (MSTN) gene is effective in muscle tissue overgrowth in species such as cattle, sheep, pig and mouse. Later on, with administration of genome editing techniques on rabbit (17), pig (16) and dog (31), double muscling trait was successfully achieved by modifying MSTN gene. It can be inferred from the studies that the removal of MSTN’s inhibitory role will leads to muscle increase, an observation similar to that of other mammalian species. Therefore, it can be considered as a candidate gene for growth and carcass traits. This simple mutation can be used as a model for genetic engineering of farm animals to improve growth traits.

    Materials and Methods

    In total, blood samples of 15 sheep from each breed of Dalagh, Baluchi and Zel were collected. Genomic DNA was extracted from whole blood using Guanidium Thiocyanate-Silica Gel method (Diatom DNA Prep. 100, Isogene, Russia) following the manufacturer’s instruction. The integrity of the extracted DNA was assessed by electrophoresis on a 0.8% agarose gel and the purity of the obtained DNA was evaluated by Epoch microplate spectrophotometer (BioTek, USA). A 2180 bp region from 3UTR of ovine MSTN gene was amplified by standard PCR reaction in a total volume of 25 µl. Tree sets of specific overlapping primers were used to amplify part of the 3UTR region in MSTN gene (Table 1). The PCR products then purified by ethanol precipitation method (14) and sequenced. The sequencing results homology were checked by BLAST and assembled using CLC sequence viewer 8.0. Then miRNA target sites were analyzed to create a potent in silico modification which serve as a target site for the microRNAs miR-1 and miR-206 with suppressing effect on MSTN transcript. At the end to assess the formation of any new and undesired motif due to the creation of our in silico modification, the whole area analyzed with the motif finder application.

    Results and Discussion

    This study was performed to identify and compare DNA sequence of a 2180 bp region from the 3'UTR of myostatin gene in Dalagh, Baluchi and Zel sheep breeds and with the aim of introducing an in silico modification to introduce a mutation with a positive impact on growth rate. Results showed that there was a high similarity between 3' UTR sequences of GDF8 gene in Zel, Dalagh and Baluchi sheep breeds. All samples were monomorphic and had the g+6723G allele, which do not cause double muscle phenotype (Figure 2). An in silico approach employed to modify the 3'UTR of the myostatin gene in this indigenous sheep breeds in order to create miR-1 and miR-206 (ACATTCCA) target sequences naturally occurring in the Texel sheep (Figure 3). After applying these changes, the possibility of creating unwanted new regulatory elements was investigated using the motif finder software. The results showed that the introduced mutations did not create any new motifs that had a known regulatory role in mammals. It was demonstrated that this mutation can attribute to 38% of the additive genetic variance for muscle depth in the Charollais lambs (12). In another study, this mutation found to have a significant increase in muscle mass and reduced carcass fat in Norwegian White sheep (6). Therefore, this single modification can be considered as the best mutation for double muscling due to its large effect on the muscling phenotype.

    Conclusion

    Due to the large effect that g+6723G>A mutation has on the phenotype double muscle and also the absence of other known effects on the phenotypes, this mutation could be considered as one of the best candidates for genome editing that can create indigenous sheep with overgrown muscle phenotype in the future by using of genetic engineering techniques. It is feasible to introduce this mutated allele by genetic engineering methods as a desirable genetic modification for improving indigenous sheep breeds. Advantages of using this approach include increasing the genetic progress of breeding programs in compare to traditional methods and maintaining the environmental compatibility of indigenous sheep breeds.
    Muscle tissue, Sheep, Myostatin, Micro RNA

    Keywords: Muscle tissue, Sheep, Myostatin, Micro RNA
  • Alireza Ayyoubi, Malek Shakeri *, Mahdi Zhandi, Hedayatollah Ghourchian Pages 121-132
    Introduction

    Early pregnancy diagnosis is a key factor in shortening the calving interval through identifying the non-pregnant animals to rebreed them at the earliest time after artificial insemination (AI). Bovine pregnancy-associated glycoproteins (PAGs) are produced by mono- and binucleated trophoblastic cells of the pregnant cow’s placenta. Detection of PAG in the maternal circulation has been used to accurately diagnose pregnancy. Several studies have used commercial PAG tests to determine pregnancy status in dairy cows and heifers. Pregnancy-specific protein B (PSPB) or PAG1 was the first identified member of the PAG family and commercial diagnostic kits still utilize PAG1 as a pregnancy marker. In recent years, the use of nanoparticles in immunosensors has been increased their sensitivity and increased the traceability of antigen-antibody responses. Due to the limitation of using ultrasound and other methods for pregnancy diagnosis in the first 30 days after inoculation, the aim of this study was to apply the pregnancy-associated glycoprotein detection method in order to reduce the time of pregnancy diagnosis. For this purpose, a sandwich ELISA immunosensor was designed for the detection of PAGs and named Nano-kit.

    Materials and Methods

    Magnetic nanoparticles were used to enhance the contact area between antibodies and antigens. Streptavidin and biotin were used for their high binding affinity to bind the antibodies and enzymes to nanomagnet. The synchronization technique and artificial insemination (AI) was performed in Holstein dairy cows (n = 58). Pregnancy status was determined by transrectal ultrasonography (30 days after AI). Furthermore, transrectal palpation was carried out by a skilled veterinarian on day 60 after AI to determine the pregnancy status of cows which were previously detected as pregnant. For PAG1 analysis, blood samples (10 mL) were collected daily from 18 to 30 days after AI. Blood samples were collected by venipuncture from the tail vein into evacuated tubes containing EDTA as an anticoagulant and were processed 1–3 h after sampling. The samples were centrifuged and plasma samples were transferred to fresh tubes and were stored at −20°C until they were assessed. Plasma concentrations of PAG1 were determined by nano- kit and commercial kit. Differences in the level of PAG-1 were evaluated by repeated measures ANOVA (SAS 9.4) over days of sampling (18 to 30). Values of PAG-1 in pregnant cows were considered as the reference. Data were presented as means ± SD and differences were considered significant at P<0.05.

    Results and Discussion

    By doing Ovsynch protocol, of the 54 cows enrolled in the first AI, 48% (26/54) of synchronized cows were diagnosed pregnant 30 days after AI using transrectal ultrasonography. From day 30 to 60 after AI, 73% (19/26) of cows maintained pregnant and the pregnancy loss from day 32 to 60 after AI was 17% (7/26). Measurement of different concentrations of PAG1 (standards) using a commercial kit and nano-kit showed that nano-kit were more sensitive than the commercial kit and detected a concentration of 0.03 ng/mL. The first increase in plasma concentration of PAG1 occurred on d 23 after AI in pregnant cows and PAG1 concentration in serum increased from d 22 to 30 after AI and it was affected by day (P < 0.001). Cows diagnosed as pregnant on day 60 after AI had a higher PAG concentration on day 24 compared with cows that were diagnosed as non-pregnant (2.28 ± 0.15 ng/mL vs 0.7 ± 0.18 ng/mL, respectively; P < 0.001). Accuracy in predicting pregnancy at day 24 of gestation based on circulating concentration of PAGs was 95 % for 1.93 ng/mL. Generally, based on the results of this study, the cows with mean PAG1 concentration more than 2.28 ± 0.07 ng/mL on 24 and mean PAG1 concentration more than 9.2 ± 0.07 ng/mL on day 30 of pregnancy, remained pregnant until day 60 of pregnancy. Furthermore, in cows diagnosed pregnant on day 24 of pregnancy but were not pregnant on day 30 after AI, blood plasma PAG1 concentration on day 24 after AI was 1.03 ± 0.66 ng/ml.

    Conclusion

    Based on these results, PAG concentrations at day 24 of gestation are higher in pregnant compared to non-pregnant dairy cows and could be applied in diagnosing pregnancy at day 24 of gestation; however, further study is needed to determine the potential of PAG1 in pregnancy diagnosis in dairy cows.
    Abortion, Glycoprotein, Nano-kit, Pregnant cow

    Keywords: Abortion, Glycoprotein, Nano-kit, Pregnant cow