فهرست مطالب

پژوهشهای علوم دامی ایران - سال هفتم شماره 2 (تابستان 1394)

فصلنامه پژوهشهای علوم دامی ایران
سال هفتم شماره 2 (تابستان 1394)

  • تاریخ انتشار: 1394/09/30
  • تعداد عناوین: 11
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  • رضا ولی زاده، مهدی محمودی ابیانه، امین صلاحی صفحات 120-128
    در این مطالعه ترکیب شیمیایی، مقدار تولید گاز و تجزیه پذیری شکمبه ای گیاه کامل نی (Pragmates australis) عمل آوری شده با افزودنی های مختلف بررسی شد. تیمارهای آزمایشی شامل: 1) گیاه کامل نی تازه سیلو شده بدون افزودنی (شاهد)، 2) عمل آوری شده با 4% سود، 3) عمل آوری شده با 4% اوره، 4) عمل آوری شده با 10% ملاس، 5) عمل آوری شده با 4% اوره + 10% ملاس و 6) عمل آوری شده با 4% اوره + 10% ملاس + 4% سود بود. در کلیه تیمارها گیاه کامل نی خرد شده با مواد مختلف مخلوط سپس در ظروف آنتی باکتریال (با نام تجاری TETRA LOCK) به مدت 60 روز سیلو شد. درصد NDF و ADF در تیمار حاوی اوره بالاترین و در تیمار عمل آوری شده با سود کمترین مقدار بود (01 /0 >P). میزان پروتئین خام و خاکستر به ترتیب در تیمار عمل آوری شده با اوره و در تیمار عمل آوری شده با سود بیشترین مقدار داشت. میزان نیتروژن آمونیاکی در سیلاژ حاوی اوره بالاترین و سیلاژ دارای مکمل ملاس پایین ترین pH را نشان داد. نرخ تولید گاز در نی عمل آوری شده با اوره کمتر از سایر تیمارها بود. پتانسیل تجزیه پذیری شکمبه ای در نمونه های عمل آوری شده با سود و ملاس به صورت معنی داری (05 /0 >P) بالاتر از تیمارهای شاهد و عمل آوری شده با اوره بود. این مطالعه نشان داد که برداشت، عمل آوری و ذخیره سازی گیاه کامل نی به صورت سیلو می تواند به عنوان یک منبع غذایی مناسب به ویژه در مناطقی که با کمبود خوراک دام روبرو است، مد نظر قرار گیرد.
    کلیدواژگان: ترکیب شیمیایی، تولید گاز، خصوصیات کیفی، سیلو، نی
  • عبدالمنصور طهماسبی، وحید وثوقی، علیرضا فروغی صفحات 129-138
    به منظور بررسی اثر سطوح مختلف محدودیت مصرف آب روی عملکرد رشد و برخی ازالکترولیت ها و فراسنجه های خون در بره نر بلوچی از 21 بره تک قلو با میانگین سن (4 ± 90 روز) و میانگین وزن (2/2± 7/ 26 کیلوگرم) استفاده شد. بره ها به طور تصادفی به سه دسته بر اساس میزان آب مصرفی تقسیم شدند (7 بره به ازای هر گروه). در گروه شاهد به بره ها اجازه مصرف آب بطور آزاد در طول دوره آزمایش داده شد. مصرف آب بره های گروه 2 و 3 به ترتیب به 72% و 44% میانگین مصرف روزانه محدود شد. طول مدت آزمایش 49 روز بود که شامل 14 روز عادت پذیری و 35 روز دوره آزمایش که این 35 روز به 3 دوره آزمایشی به ترتیب شامل، 7 روز دوره کاهش تدریجی آب مصرفی، 14 روز دوره محدودیت مصرف آب به مقدار ثابت 72% و 44% میانگین مصرف روزانه برای تیمارهای 2 و 3 و 14 روز دوره دسترسی آزاد به آب برای همه تیمارها تقسیم شده بود. میزان آب و خوراک مصرفی به طور روزانه و افزایش وزن، الکترولیت ها و فراسنجه های خون شامل گلوکز، تری گلیسرید، کراتینین، نیتروژن اوره ای خون، کلسترول، پروتئین کل، کورتیزول، هماتوکریت و هموگلوبین خون، کلسیم، سدیم و پتاسیم در روزهای1، 7، 21 و 35 آزمایش اندازه گیری شدند. نتایج بدست آمده نشان داد که مقدار ماده خشک مصرفی و نسبت آب مصرفی به خوراک مصرفی و افزایش وزن روزانه در گروه 2 و 3 نسبت به گروه شاهد اختلاف معنی داری داشت. همچنین دهیدراسیون موجب افزایش غلظت سدیم، کلسترول، کراتینین، نیتروژن اوره ای خون و مقدار هموگلوبین خون در مقایسه با گروه شاهد شد. بطور کلی نتایج این آزمایش نشان داد که بره نژاد بلوچی می تواند محدودیت مصرف آب را برای مدت بیش از 14 روز بدون تغییرات عمده در فراسنجه ها و الکترولیت های خون تحمل کند.
    کلیدواژگان: بره های نر بلوچی، عملکرد، فرآسنجه های خون، محدودیت مصرف آب
  • مصطفی غلامی، احمد حسن آبادی، حسن نصیری مقدم، ابوالقاسم گلیان صفحات 139-152
    این آزمایش به منظور بررسی اثر سطوح مختلف آرژنین و پروتئین قابل هضم در دوره آغازین بر عمکرد، صفات لاشه و فراسنجه های سرم خون جوجه های گوشتی انجام شد. چهارصد قطعه جوجه خروس گوشتی یکروزه سویه راس 308 در سن 10-1 روزگی به 10 تیمار دارای 4 تکرار اختصاص یافت. آزمایش در قالب طرح کاملا تصادفی به صورت فاکتوریل 5×2 انجام شد. آرژنین قابل هضم شامل پنج سطح 05 /1، 18 /1، 31 /1 (توصیه راس)، 44 /1 و 57 /1 درصد و پروتئین قابل هضم شامل 18 و 20 درصد جیره بود. پس از 10 روزگی تمامی جوجه ها جیره یکسان دریافت کردند. نتایج نشان داد که سطوح آرژنین و پروتئین و اثرات متقابل این دو تاثیر معنی داری بر مصرف خوراک، افزایش وزن جوجه ها و ضریب تبدیل داشت. سطوح پروتئین خوراک بر وزن نسبی کبد و چربی حفره شکمی در سن 10 روزگی، وزن نسبی روده درسن 42 روزگی معنی دار بود. اثرات سطوح مختلف آرژنین بر وزن نسبی کبد و چربی حفره شکمی، در سن 10 روزگی معنی دار بود. اثرات متقابل سطوح مختلف آرژنین و پروتئین بر وزن نسبی کبد و طول نسبی دئودنوم و ژژنوم در دوره آغازین ازنظر آماری معنی دار بود. اثرات سطوح متفاوت پروتئین بر غلظت پروتئین کل، آلبومین و فسفر سرم معنی دار بود. اثر سطوح مختلف آرژنین بر غلظت اسید اوریک و کلسیم سرم معنی دار بود. با توجه به نتایج این آزمایش می توان گفت سطح آرژنین و پروتئین قابل هضم توصیه شده توسط شرکت راس مناسب می باشد.
    کلیدواژگان: آرژنین قابل هضم، پروتئین قابل هضم، جوجه گوشتی، عملکرد، فراسنجه های خون
  • سجاد محب علی، محمد سالارمعینی صفحات 153-161
    این مطالعه به منظور بررسی ارزش تغذیه ای دانه خردل سیاه فرآوری شده با یک درصد سولفات آهن در سطوح صفر، 5، 10 و 15 درصد بر پارامترهای عملکرد رشد، برخی فراسنجه های خونی، کیفیت گوشت و هزینه خوراک به ازای هر کیلو گرم وزن زنده در بلدرچین های ژاپنی انجام شد. به این منظور از 240 قطعه جوجه بلدرچین ژاپنی یک روزه در قالب طرح کاملا تصادفی با 4 تیمار و 4 تکرار، از سن 35-7 روزگی استفاده شد. پروتئین خام، عصاره اتری، خاکستر، رطوبت و الیاف خام در ماده خشک دانه خردل به ترتیب، 6 /28، 3 /40، 5، 7 و 8 /14 درصد و ارزش انرژی قابل سوخت و ساز ظاهری تصحیح شده برای نیتروژن آن بر اساس ماده خشک 4630 کیلوکالری بر کیلوگرم بود. مصرف سطوح مختلف دانه خردل فرآوری شده، اثر معنی داری بر مصرف خوراک، افزایش وزن روزانه و ضریب تبدیل نداشت. وزن نسبی قلب، کبد، دستگاه گوارش و وزن قطعات لاشه به طور معنی داری تحت تاثیر تغذیه سطوح مختلف خردل فرآوری قرار نگرفت، اما وزن نسبی پانکراس افزایش نشان داد. تیمارهای غذایی تاثیر معنی داری بر میزان مالون دی آلدهاید، پی اچ و سایر پارامترهای کیفیت گوشت (افت خونابه، افت در نتیجه پخت و ظرفیت نگهداری آب) نداشتند. از نظر اقتصادی هزینه خوراک برای تولید یک کیلو وزن زنده با استفاده از دانه خردل فرآوری شده در سطح 10 درصد کمترین هزینه را داشت. لذا استفاده از دانه خردل فراوری شده تا سطح 10 درصد، اقتصادی تر به نظر می رسد.
    کلیدواژگان: بلدرچین ژاپنی، پارامترهای خونی، دانه خردل فراوری شده، عملکرد رشد
  • نگین امیری، محمد سالارمعینی *، سیما تشرفی صفحات 162-172

    این تحقیق به منظور مطالعه قابلیت تغذیه جنینی بر درصد جوجه درآوری، وزن اولیه بعد از هچ، عملکرد رشد، فراسنجه های خونی، سیستم ایمنی جوجه های گوشتی و مرفولوژی پرزهای روده انجام شد. در این مطالعه 240 عدد تخم مرغ بارور سویه گوشتی راس 308 (سن گله مادر 28 هفتگی)، در قالب طرح کاملا تصادفی با 5 تیمار مورد استفاده قرار گرفتند. به هر تیمار 3 تکرار و به هر تکرار 16 عدد تخم مرغ اختصاص داده شد. تیمارها عبارت بودند از بدون تزریق (شاهد 1)، تزریق 7 /0 میلی لیتر آب مقطر (شاهد 2) و یا محلول اسیدهای آمینه، دکستروز 10 درصد و یا دکستروز 20 درصد به مایع آمنیوتیک تخم مرغ های بارور در روز 5 /17 انکوباسیون. جوجه ها بعد از هچ به مدت 36 ساعت از دسترسی به خوراک محروم بودند. وزن تولد در تیمار اسید آمینه نسبت به تیمار بدون تزریق و تزریق آب مقطر به طور معنی داری بیشتر بود. کمترین میانگین وزنی و مصرف خوراک در کل دوره پرورش مربوط به تیمار بدون تزریق بود. تیمارها تاثیری معنی داری بر ضریب تبدیل غذایی نداشتند. میزان گلوکز خون جوجه ها پس از هچ در تیمار تزریق دکستروز 20 درصد نسبت به تزریق آب مقطر بیشتر بود. همچنین میزان تریگلیسرید در تیمار تزریق آب مقطر بیشترین مقدار را نشان داد. تزریق اسید آمینه و دکستروز 10 و 20 درصد سبب افزایش وزن نسبی تیموس (در سن یک و 3 روزگی) گردید همچنین بیشترین وزن نسبی بورس در سن یک روزگی در تیمار تزریق دکستروز 10 درصد مشاهده شد که البته با تیمار دکستروز 20 درصد اختلاف معنی داری نداشت. تزریق دکستروز 20 درصد سبب افزایش طول پرز نسبت به سایر تیمارها در سن سه روزگی گردید. بر اساس نتایج این آزمایش، به نظر می رسد تزریق مواد مغذی می تواند در بهبود عملکرد جوجه ها موثر باشد.

    کلیدواژگان: اسید آمینه، تغذیه جنینی، جوجه گوشتی، دکسترین، کیسه آمنیون
  • فرهاد رستمی، کامران طاهرپور، حسینعلی قاسمی، فاضل پور احمد صفحات 173-183
    این آزمایش به منظور مقایسه اثر افزودن گل میمونی با آنتی بیوتیک ویرجینامایسین و سین بیوتیک به جیره بر عملکرد و پاسخ ایمنی جوجه های گوشتی انجام شد. تعداد 250 قطعه جوجه خروس (سویه تجاری راس 308) یکروزه به 25 گروه 10 قطعه ای (پنج تیمار و پنج تکرار به ازای هر تیمار) تقسیم شدند. تیمارهای آزمایشی شامل جیره پایه بدون ماده افزودنی (جیره شاهد) و جیره پایه حاوی 02 /0 درصد آنتی بیوتیک ویرجینامایسین، سطح تجاری سین بیوتیک (در جیره آغازین 15 /0 درصد و در جیره های رشد و پایانی 10 /0 درصد)، 4 /0 و 8 /0 درصد گیاه گل میمونی بود. نتایج حاصل از این آزمایش نشان داد که جوجه های تغذیه شده با جیره های حاوی گل میمونی، سین بیوتیک و آنتی بیوتیک در پایان دوره پرورش به طور معنی داری ضریب تبدیل بهتری نسبت به گروه شاهد داشتند. در مقابل، افزایش وزن و خوراک مصرفی جوجه ها در کل دوره (1 تا 42 روزگی) تحت تاثیر تیمارهای آزمایشی قرار نگرفت. اعمال همه تیمارهای آزمایشی به استثنای تیمار 4 /0 درصد گل میمونی سبب افزایش معنی دار درصد لنفوسیت و کاهش معنیدار نسبت هتروفیل به لنفوسیت در مقایسه با تیمار شاهد شدند. پرنده های تغذیه شده با تیمارهای سینبیوتیک و 8 /0 درصد گل میمونی به طور معنی دار پاسخ ثانویه پادتن بالاتری علیه واکسن های نیوکاسل و گامبورو را در مقایسه با پرندگان گروه شاهد نشان دادند. از نتایج این مطالعه می توان نتیجه گرفت که افزودن 8 /0 درصد گل میمونی به جیره جوجه های گوشتی سبب بهبود بازده خوراک و پاسخ ایمنی می شود و می تواند بعنوان یک جایگزین مناسب برای آنتی بیوتیک در تغذیه جوجه های گوشتی مدنظر قرار گیرد.
    کلیدواژگان: پاسخ ایمنی، جوجه گوشتی، عملکرد، گل میمونی، هتروفیل:لنفوسیت
  • عاطفه سید دخت، علی اصغر اسلمی نژاد، مرتضی بیطرف ثانی صفحات 184-190
    سن اولین زایش اثر مهمی روی سودآوری و مدیریت تولیدمثلی گله گاو شیری دارد، به طوری که زایش تلیسه ها در سن بیشتر از 24 ماهگی به دلیل از دست رفتن فرصت تولید شیر و کاهش روز های تولیدی زندگی دام، باعث افزایش هزینه های تولید در صنعت گاو شیری می شود. به منظور برآورد اجزای ژنتیکی و بررسی روند تغییرات سن اولین زایش گاوهای شیری هلشتاین در ایران از 19499 رکوردهای تولید و تولید مثل 96 گله گاوهای شیری هلشتاین طی سال های 1375 لغایت 1387 استفاده شد. داده ها با استفاده از یک مدل تک صفتی و نرم افزار Wombat آنالیز شد. وراثت پذیری صفت سن اولین زایش 0994 /0 برآورد گردید. میانگین سن اولین زایش گاوهای شیری هلشتاین در ایران طی سال های 1375 لغایت 1387، 91 /24 ماه برآورد شد که طی سال های مورد مطالعه به واسطه تلقیح و زایش زودتر تلیسه ها کاهش یافته است، به طوری که گاوهایی که در سال های 1375 و 1376 متولد شده اند بیشترین سن در اولین زایش را داشتند و گاوهایی که در سال های 1386 و 1387 متولد شده اند کمترین سن را در زمان اولین زایش نشان دادند. با توجه به مقادیر برآورد شده ارزش های اصلاحی صفت سن اولین زایش، روند ژنتیکی این صفت طی سال های تولد 1375 لغایت 1387 برآورد شد. بدین صورت که روند ژنتیکی در بعضی سال ها مثبت و برای بعضی سال های مورد مطالعه منفی برآورد شد و نشان می دهد که در راهبردهای انتخاب، کاهش ژنتیکی سن اولین زایش در گله های ایران مد نظر قرار نگرفته است، هرچند که از نظر فنوتیپی این صفت کاهش داشته است. گاوهای استان های یزد، مرکزی و خراسان جنوبی بیشترین سن و گاوهای استان های کرمانشاه، آذربایجان شرقی و اردبیل کمترین سن اولین زایش را داشتند. شرایط اقلیمی و آب و هوایی مناسب می تواند در افزایش باروری تلیسه ها و کاهش سن اولین زایش موثر باشد، هرچند عوامل مدیریتی، با وجود عوامل جوی مناسب در برخی از استان های کشور اثر به سزایی روی این صفت داشت.
    کلیدواژگان: روند فنوتیپی، روند ژنتیکی، سن اولین زایش، سودآوری، گاو شیری
  • مرتضی بیطرف ثانی، محمدرضا نصیری، علی اصغر اسلمی نژاد، محمد مهدی شریعتی صفحات 191-198
    لایه بندی جمعیتی5 یکی از مسائلی است که می تواند در مطالعات ارتباطی ژنومی باعث بروز خطا شود. در تحقیق حاضر از شیوه مطالعه ارتباطی ژنومی (طرح Case-Control) برای شناسایی اثر لایه بندی جمعیتی استفاده شد. جامعه آماری و ژنوم 10000 گاو در طی 100 نسل با روش تعادل رانش – جهش ژنتیکی شبیه سازی و سپس با استفاده از جامعه مذکور، 800 گاو آمیخته و خالص با 50000 SNP تعیین ژنوتیپ شده در طول 30 جفت کروموزوم، ایجاد شدند. نتایج نشان داد که هر چه نسبت Case/Control در بین جوامع خویشاوند از عدد یک بیشتر منحرف شود، شاخص آماری لامبدا که نشان دهنده اثر لایه بندی جمعیتی است، افزایش خواهد یافت. به طوری که شاخص لامبدا در مدل ژنتیکی افزایشی با نسبت های 1، 77 /0 و 33 /0 به ترتیب 42 /0، 31 /11 و 77 /97 و در مدل ژنتیکی عدم غلبه، به ترتیب 47 /0، 21 /8 و 40 /57 برآورد گردید. اثر لایه بندی جمعیتی در بین گروه های مختلف جامعه گاوهای آمیخته وجود نداشت و شاخص لامبدا در مدلهای ژنتیکی عدم غلبه، غلبه کامل، مغلوبیت، افزایشی و فوق غلبه به ترتیب 55 /0، 66 /0، 89 /0، 76 /0 و 41 /0 برآورد شد. نتایج تحقیق حاضر نشان داد که برای کنترل اثر لایه بندی جمعیتی در مطالعات ارتباطی ژنومی، گروه های case-control نبایستی از جوامعی مختلف با اجداد و درجه خویشاوندی متفاوت انتخاب شوند، مگر با نسبتهای کاملا یکنواخت در دو جامعه. همچنین، پیشنهاد می گردد از گاوهای آمیخته به دلیل عدم وجود عامل ساختار ژنتیکی جمعیتی استفاده گردد.
    کلیدواژگان: لایه بندی جمعیتی، مطالعات ارتباطی، SNP
  • زهرا یگانه پور، هدایت الله روشنفکر، جمال فیاضی، میر حسن بیرانوند، محمد قادرزاده صفحات 199-207
    هدف از مطالعه حاضر بررسی شجره و افت همخونی بر صفات رشد در گوسفند لری می باشد. برای انجام پژوهش حاضر از اطلاعات شجره و رکوردهای مرتبط با صفات رشد شامل وزن تولد، وزن شیرگیری، وزن شش ماهگی و وزن نه ماهگی 6440 راس بره حاصل از 273 راس قوچ و 1955 راس میش که طی سال های 1380 تا 1389 از مرکز تحقیقات کشاورزی و منابع طبیعی استان لرستان جمع آوری شده بود، استفاده گردید. تجزیه شجره از برنامه Pedigree، برآورد ضریب همخونی از برنامه CFC و برای محاسبه میزان تابعیت صفات از همخونی، از نرم افزار WOMBAT استفاده گردید. در کل جمعیت تعداد حیوانات همخون 2126 دام بودند که 33 درصد گله را شامل می شد. میانگین ضریب همخونی کل جمعیت 69 /0 درصد و میانگین ضریب همخونی جمعیت همخون 24 /2 درصد برآورد گردید. روند تغییرات سالیانه ضریب همخونی 21 /0 درصد بود که به لحاظ آماری معنی دار می باشد. کمترین و بیشترین مقدار همخونی به ترتیب صفر و 85 /26 درصد محاسبه شد. پایین بودن ضریب همخونی گله می تواند ناشی از نامعلوم بودن شجره برخی حیوانات، نوسانات مدیریتی و تا حدی ممانعت از آمیزش خویشاوندان نزدیک باشد. اثر همخونی در جمعیت گوسفندان لری با استفاده از مدل های حیوانی مناسب برای هر صفت تولیدی بررسی شد. با افزایش هر یک درصد افزایش در همخونی، وزن تولد 4 گرم، وزن شیرگیری 3 /20 گرم، شش ماهگی 247 گرم و نه ماهگی 5 /4 گرم کاهش پیدا کرده است. استفاده از یک برنامه آمیزش مستقیم تحت کنترل در گله حاضر می تواند جایگزینی مناسب برای حفظ سطح همخونی شود.
    کلیدواژگان: افت ناشی از همخونی، روند همخونی، صفات رشد، گوسفند نژاد لری، مدل دام
  • فائزه قربانی، همایون فرهنگ فر، نظر افضلی، محمد ابراهیم نویدی زاده صفحات 208-217
    در هر برنامه اصلاح نژادی هدف آن است که ارزش اصلاحی حیوانات، با دقت و صحت بالایی پیش بینی گردد تا بر اساس آن بتوان بهبود ژنتیکی قابل ملاحظه ای را در طول زمان برای صفات مورد نظر، ایجاد نمود. هدف از این تحقیق، بررسی صحت ارزش اصلاحی پیش بینی شده در مرغان بومی خراسان برای صفت وزن بدن در سن هشت هفتگی بود. داده های مورد استفاده، تعداد 47000 رکورد وزن بدن متعلق به 47000 جوجه (نتاج 753 خروس و 5154 مرغ)، جمع آوری شده طی هفت نسل (1391-1385) بود. مدل آماری مورد استفاده برای آنالیز داده ها، یک مدل حیوانی بود، که در آن گروه همزمان نسل - هچ - جنس، متغیر کمکی وزن جوجه در سن یک روزگی، و اثرات تصادفی ژنتیکی افزایشی مستقیم و مادری گنجانده شدند. مدل مزبور بر داده ها توسط نرم افزار DMU برازش داده شد. وراثت پذیری مستقیم و مادری صفت وزن بدن در سن هشت هفتگی به ترتیب 4387 /0 و 0483 /0 برآورد گردید. میانگین ارزش اصلاحی مستقیم و مادری به ترتیب 65 /76 و 91 /7- گرم و میانگین صحت ارزیابی ژنتیکی (مستقیم و مادری) به ترتیب 741 /0 و 427 /0 بود. برآورد روند ژنتیکی برای صفت وزن بدن در هفته هشتم و بر اساس ارزش اصلاحی مستقیم و مادری به ترتیب 344 /1 ± 951 /26 گرم و 199 /0± 252 /2- گرم به دست آمد. روندهای مزبور به لحاظ آماری معنی دار بودند. از آن جا که صحت انتخاب یکی از اجزای مهم اثرگذار بر میزان پیشرفت ژنتیکی صفات محسوب می گردد، لذا بر اساس نتایج تحقیق حاضر، نتیجه گیری می شود که در رابطه با صفت وزن بدن در سن هشت هفتگی مرغان بومی خراسان، انتخاب ژنتیکی، با صحت نسبتا بالایی اجرا گردیده است.
    کلیدواژگان: صحت انتخاب، مدل حیوانی، مرغان بومی، وزن بدن
  • عبدالرضا جهانبخشی، حمیدرضا احمدنیای مطلق، مهسا جوادی موسوی، ادریس رحیمی کیا صفحات 218-224
    در این مطالعه، اثر سطوح مختلف اسانس گیاه سیر بعنوان یکی از مهم ترین گیاهان دارویی که می تواند تاثیر به سزایی در فیزیولوژی بدن داشته باشد بر شاخص های رشد، بقاء، پارامترهای خونی و بیوشیمیایی ماهی گورامی سه خال (Trichogaster trichopterus) مورد بررسی قرار گرفت. جیره های آزمایشی با سه سطح(سه تیمار وهر تیمار شامل سه تکرار) 10 /0، 15 /0و 20 /0 گرم اسانس سیر بر کیلوگرم غذا و جیره شاهد تهیه شدند. ماهیان با میانگین وزنی 10 /0± 33 /4 گرم در آکواریوم های 70 لیتری که دما1±27، پی- اچ 5 /0±8 /7 و سختی آب 5 /2 ± 299 بود نگهداری و به مدت 60 روز با جیره های آزمایشی تغذیه شدند و در پایان دوره شاخص های رشد، بقاء، شاخص های خون شناسی، گلوکز و پروتیئن سرم اندازه گیری شدند. نتایج حاصل نشان داد که رشد و ضریب تبدیل غذایی در تیمارهای آزمایشی در مقایسه با گروه شاهد صورت معنی داری به ترتیب افزایش و کاهش داشتند. میزان هماتوکریت، هموگلوبین، گلبول های سفید و قرمز خون در تیمارهای حاوی اسانس سیر به صورت معنی داری در مقایسه با گروه شاهد افزایش یافت. در حالی که اسانس سیر اثر معنی داری بر پارامترهای میانگین حجم گلبول، میانگین هموگلوبین گلبول و میانگین غلظت هموگلوبین گلبول نداشت. میزان پروتئین خون در تیمارهای تغذیه شده با اسانس سیر به صورت معنی داری افزایش و میزان گلوکز خون به صورت معنی داری نسبت به گروه شاهد کاهش یافت. با توجه به نتایج حاصل از این تحقیق می توان گفت که افزودن اسانس گیاه سیر می تواند نقش مثبتی در ارتقاء وضعیت عمومی، ایمنی و رشد ماهی گورامی سه خال داشته باشد.
    کلیدواژگان: پروتئین، ضریب تبدیل غذایی، گلوکز، هماتوکریت
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  • Valizadeh, Reza, Mahmoodi Abyaneh, Mahdi, Salahi, Amin Pages 120-128
    Introduction
    Pragmates australis (Pa) (common reed) is a riverside perennial grass found in wetlands throughout temperate and tropical regions of the world. Pa grows in many wetlands around rivers in Iran. Animal feed restriction is the main problem of Iranian animal production systems and this feed resource can be fed to native livestock especially in rural areas. Ensiling Pa could improve its feeding value. The aim of this study, therefore, was to measure the chemical composition, gas production and rumen degradability characteristics of the fresh and ensiled Pa with different additives.
    Materials And Methods
    Plant samples were harvested during growth season from the city of Bojnoord,in Iran. The Pa samples were chopped and ensiled into airtight plastic bags as follow; 1)the fresh whole plant of Pa as control (Pa), 2) pa + 4% NaOH, 3) Pa+4% urea, 4) Pa+10% molasses, 5) Pa+4% urea +10% molasses and 6) pa+4% urea + 10% molasses +4% NaOH (on DM basis). Duration of the ensiling process lasted 60 days. Chemical composition of the samples was measured through the ordinary lab methods. The in vitro gas production was determined at 2, 4, 6, 8, 12, 24, 36, 48, 72 and 96 hrs intervals after incubation. The in situ rumen degradability was also determined at 0, 2, 4, 8, 12, 24, 36, 48, 72, 96 hrs after incubation. The experiment data were analyzed in a completely randomized design.
    Results And Discussion
    NDF and ADF contents of the ensiled samples with urea were the highest whereas they were the lowest in the NaOH treated samples. CP content of the urea treated Pa was higher than other samples. Ash content of the NaOH treated forage was significantly (P
    Keywords: Etomidate_propofol combination may be a valuable alternative when extremes of hypotensive_hypertensive responses due to propofol_etomidate are best to be avoided
  • Tahmasebi, Abdolmansoor, Vosooghi, Vahid, Froughi, Alireza Pages 129-138
    Introduction
    Sheep has played an important role in meat production and income generation in Iranian farming systems. Their profitability, however, is highly depended on nutrient supply. Drinking water is major nutrient that is responsible for different utilization of nutrients and thereby productivity and gain of animals in most parts of the world. Inadequate water and its quality such as salinity, acidity, and toxic elements depress the biological, physiological process and performance of sheep. Iran has a different type of Agro-ecological climate but most part of this country is under arid or semi arid condition and thus face to shortage of water. Bluchi sheep is the most important breed which is well adapted in harsh marginal arid in the east region of Iran, however, little information is available regarding of the mechanism of adaptation in this breed for biological process to allowing them to cope during water restriction in this zone. Therefore this experiment was conducted to investigate some electrolytes and blood metabolites and hormones under the influence of different levels of water availability and the ability to tolerate water restriction in Baluchi lambs.
    Materials And Methods
    This study was conducted during May-June 2013 at the Baluchi sheep research center (Abbas Abad) in Northeast of Iran. Twenty-one single lambs, (90 ± 4 days old and 26.7 ± 2.2 kg BW) were used in this study. Lambs were randomly subjected to three levels of water restriction (seven lambs per group). Lambs in control group, allowed to drinking water freely. For the second treatment, the water supply to the lambs were restricted to 72% of their average daily intake and for the third treatment, water intake was restricted to 44% of their average daily intake. The whole experiment period was 49 days and was divided in 3 periods with 14 days adaptation.. The three time periods were including, 7 days for the stepwise water reduction period, and 14 days fixed limit to the amount of 72% and 44% of their average intake for treatment 2 and 3 and during last period (14 days) all groups had free access to water. The sheep were allocated to individual feeding pens and feed were provided ad libitum. Weight gain, blood metabolites and electrolytes (glucose, triglycerides, creatinine, blood urea, cholesterol, total proteins, cortisol, hematocrit, blood hemoglobin, Na+,Ca2+, K+ were determined on 1, 7, 21 and 35 days of experiment. The data from experiments were analyzed using Minitab and GLM procedure and for comparison of means Duncan test was applied.
    Results And Discussion
    The obtained results indicated that feed intake, daily weight gain and the ratio of water consumption to feed intake in treatments 2 and 3 in compare with control group was statistically different. The results showed that there was a direct relationship between the reduction in water consumption and feed intake. It seems that this weight loss in treatments 2 and 3 can be due to a combination of reduced feed intake and loss of body water. Additional dehydration led to increase blood concentration creatinine, blood urea in compare with the control group. High blood urea and creatinine may be due to an imbalance in the production and disposal of these substances by the kidneys and fecal. Water restriction led to increased concentration of plasma sodium than the control group, however this increase was not significant. Treatment 3, on day 21, compared with other treatments,was an exception and one of the possible reasons for this can be due the influence of the hormone aldosterone and ADH on the kidneys. Hematocrit and hemoglobin in the blood tend to rise by water restriction but this will not led to significant differences between treatments. Except the hemoglobin on day 21 between treatments 3 with other treatments, significant differences were found which can be due to reduced blood plasma volume because of dehydration lambs. Significant differences in blood cholesterol levels were observed between treatments 3 and others on day 21 which probably this increase may be related to mobilization of fat tissue in lambs that are encountered with reducing water consumption.
    Conclusion
    The overall results showed that water restrictions could lead to a significant reduction in dry matter intake and daily weight gain in Baluchi lambs. In addition, results showed that Baluchi lamb has potential to withstand under water restriction up to 44% of their average daily water intake without significant changes in blood electrolytes. This breed can survive and adopt under arid conditions which is common in some desert area in Iran.
    Keywords: Blood metabolites, Male Baluchi lambs, Performance, Water restriction
  • Mostafa Gholami, Ahmad Hasan Abadi, Hassan Nasiri Moghadam, Abolghasem Golian Pages 139-152
    Introduction
    Nutrition and health during the first days of life has critical effect on broiler chickens performance. It is well known that diet formulation based on digestible nutrients is superior to formulation based on total nutrients. The suitable supply of essential amino acids in broilers’ diets requires proper knowledge on their metabolic effects in the body. The excessive or unbalanced intake of essential and non-essential amino acids can be harmful to broilers’ metabolism, due to amino acid antagonisms. Arginine is an essential amino acid for broilers since the urea cycle is not functional in birds. Arginine involves in the synthesis of ornithine, a precursor of polyamines that have a key role in cell division, DNA synthesis, nitric oxide (NO) synthesis, and cell cycle regulation. Also, arginine increases the release of insulin, growth hormone, and IGF-A and luteinizing hormone (LH) in the blood stream. On the other hand, in corn- soybean meal based diets arginine is the fifth limiting amino acid after methionine, lysine, threonine, and valine. Thus, this study was carried out to investigate the effects of different digestible arginine (DA) and digestible protein (DP) levels of starter diets (1-10 d) based on ideal amino acids ratio on performance, carcass traits and serum parameters in broiler chickens.
    Materials And Methods
    Four handed day-old male broiler chickes (Ross 308) were distributed in 10 treatments of 4 replicates (floor pens) each. The experiment was designed as a 2×5 factorial arrangement in a completely randomized design. Experimental diets were formulated with five levels of digestible arginine (1.05, 1.18, 1.31, 1.44 and 1.57%) and 2 levels of digestible protein (18 and 20%). Chicken were fed with experimental diets during 1 to 10 days of age, and then received similar diets formulated according to Ross 308 (2009) recommendations. All birds had free access to feed and water during the whole rearing period. Temperature was initially set at 32 °C on d 1 and decreased linearly by 0.5 °C per day up to 42d and kept constant thempreture. During the study, the birds received a lighting regimen of 23 L: 1 d from d 1 to 42. Weight gain, feed intake and feed conversion ratio were measured weekly. Blood samples were collected from wing veins of birds at 10 d of age. After 15 minutes, the blood samples were centrifuged at 3000xg for 15 minutes and serum samples were separated into tubes. Then, serums were stored at -20ºC until analyses were carried out. At 10 and 42 d of age, one bird from each pen with body weight close to the mean of each pen were selected for carcass analyses. After feed withdrawal, the selected birds were transported to the university pilot for processing. The chickens were slaughtered by cervical dislocation to determine the carcass characteristics. Data were analyzed by analysis of variance using GLM procedures (SAS, 2001). Means were compared using Duncan's new multiple ranges test (Duncan, 1955). The level of significance was reported at (P < 0.05).Resuls and Disscusiion: The results showed that feed intake, daily weight gain and feed to gain ratio (FCR), as well as their interactions were significantly affected by (digestible argenine, DA) and (digestible protein, DP) levels in starter diet. The best feed conversion ratio during starter period was related to 20 % DA and 1.31 % DA. DP levels in starter diet had a significant effect on relative weights of liver and abdominal fat (AF) on day 10 and relative weights of gizzard and ileum and also relative lengths of duodenum and ileum on day 42. DA levels significantly affected liver and AF relative weights on day 10. DA and DP interactions had significant effects on relative weight of liver and relative lengths of duodenum, jejunum and ileum on day 10 of age. Effects of DP levels on serum total protein, albumin and phosphorus concentrations were significant. DA levels had significant effects on serum concentrations of uric acid and calcium.
    Conclusion
    The results of current study showed that dietary recommendations of digestible arginine and digestible protein by Ross 308 Company support male chicken’s growth performance.
    Keywords: Blood parameters, Broiler, Digestible arginine, Digestible protein, Performance
  • Sajjad Mohebali, Mohammad Salarmoini Pages 153-161
    Introduction
    In comparison with rapeseed (canola), mustard has agronomic advantages such as drought tolerance and disease resistance, which empower this crop with a considerable oil production potential. Mustard contains toxic substances e.g. glucosinolate, erucic acid, sinapine and tannin. The substances induce unpalatability, growth retardation, low feed efficiency, thyroid gland enlargement and reproductive problems, particularly when the seed is incorporated in the diet at high levels (19, 26). The FeSO4 treatment of mustard meal is an effective method of detoxification of the meal for using in poultry diets. It can reduce the oxazolidinethione content of the meal by about 88% and the isothiocyanate content by 74% (8).As mustard seeds are available at a lower price than canola seed, in some regions of Iran, this study was conducted to investigate the effects of different dietary levels of wild black mustard seeds treated with FeSO4 on growth performance, blood metabolites, carcass characteristics and meat quality of Japanese quails.
    Materials And Methods
    Two-hundred Japanese quails of age seven-day old were randomly assigned to 4 treatment groups with 15 birds in each one of them. The experiment consists of 4 replicates in a completely randomized design. Mustard seeds were treated with FeS04-7H2O according to Daghir and Nawazish (8) procedure. Experimental treatments consisted of control diet (without mustard seed) and diets contained treated mustard seed at 5, 10 and 15% levels. The experimental period lasted up to the age of 35 days. The rearing and management conditions were the same for all groups. Experimental diets were formulated to meet the nutrients requirements of the Japanese quails (20). Chicks had free access to feed and water during the experimental period. Live body weight and feed intake were recorded weekly.On days 35 of the experimental period, blood samples of one male bird per cage (four birds per treatment) were collected to determine the blood metabolites. After slaughtering, breast muscle was separated and kept frozen at -18°C for 30 days. Breast muscle lipid peroxidation was assessed as thiobarbituric acid-reactive substance concentrations in samples by the method of Tarladgis et al. (27). The breast muscles samples were also used for pH (16), water holding capacity, drip loss (7) and cooking loss (4) tests.
    Results And Discussion
    Percentage of crude protein, ether extract, ash, moisture, and AMEn (Kcal/Kg) of the experimental mustard seed were 28.6, 40.3, 5, 7, 14.8 and 4630, respectively. Using different levels of processed mustard seed had no significant effects on growth performance compared to the control. Using untreated mustard seed (10) and mustard meal (6, 21) at more than 10 percent had detrimental effects on performance. However, it seems that using 15% treated mustard had no adverse effect on growth performance.Relative weights of the carcass traits (thigh, breast, heart, testis, gizzard, cecum and small intestine) were not significantly affected by the treatments. However, the weight of pancreas tended to be heavier in the birds fed mustard seed (P
    Keywords: Blood parameters, Growth performance, Japanese quail, Processed mustard seed
  • Negin Amiri, Mohammad Salarmoini, Sima Tasharrofi Pages 162-172
    Introduction

    Many birds do not have access to feed until 48 h after hatching (27). In ovo injection technology is a practical means for safe introduction of nutrients into developing embryos, including amino acids, carbohydrates, vitamins, L-carnitine, and hormones which may benefit post-hatch growth and BW gain (19, 36). The objective of this study was to evaluate the effects of in ovo injection of amino acids and dextrose, on hatchability, growth performance, blood metabolites, immune organs and intestinal morphology of the broiler chicks.

    Materials And Methods

    The experiment was conducted in a completely randomized design with 5 treatments, 3 replicates of 16 fertile eggs from Ross 308 breeders (28 Week old). Treatments consisted of control (no injection) and injection of 0.7 ml of different nutrients into the amniotic sac of fertile eggs on 17.5th day of incubation including: distilled water (sham), amino acids, dextrin 10% and dextrin 20%. The injection point from the broad end of the egg which was disinfected with alcohol and then 0.7 ml of each solution was injected into the amnion, using a 23- gauge needle with depth of 25 mm. The holes were then sealed using commercial glue. Hatched chicks were fasted for 36 hours. Body weight, feed intake and feed conversion ratio were recorded weekly. On days 1 and 3, blood samples were collected from one chick per replicate to determine serum metabolites (glucose, triglyceride, cholesterol,high density lipoprotein (HDL) and low density lipoprotein (LDL)). On days 1, 3, 7, 14 and 42, one bird per replicate was slaughtered and the relative weight of the immune organs (bursa of Fabricius, spleen and thymus) was determined. On day 3, villus height, crypt depth and villus height to crypt depth ratio were also measured.

    Results And Discussion

    The results showed that in ovo injection of amino acids can led to heavier birth weight compared to sham and control treatments (P=0.05). Chicks hatched from control eggs (no injection) showed the lowest significant weight gain and feed intake. Different treatments had no significant effect on feed conversion ratio. Improved growth performance could be attributed to increase in glycogen stores during the prenatal period (39). Because the late-term embryo, orally consumes the amniotic fluid (comprised primarily of water and albumen protein) prior to piping, in ovo injection of dextrose, amino acids or albumin may help to overcome any nutrient deficiency that may limit embryonic growth. Thus, it was hypothesized that administration of carbohydrates to the amnion may improve the energy level of the broiler embryo and reduce internal energy consumption (proteins and lipids) during piping, thereby increasing chick BW (45). Glucose is the major energy source in living organisms. Maintenance of glucose homeostasis during few days pre and post hatch is a great challenge in the chick’s life. The frequent activity of embryos implies a large amount of energy consumption, and higher glucose demand for fuel (45, 46). Serum glucose level after hatch was significantly higher in treatment dextrin 20% compared to sham treatment (P

    Keywords: Amino acid, Amniotic sac, Broiler, Dextrin, In, ovo injection
  • Farhad Rostami, Kamran Taherpour, Hossein Ali Ghasemi, Fazel Purahmad Pages 173-183
    Introduction
    Following the ban on antimicrobial growth promoters in poultry nutrition in EU and growing pressure on poultry producers in other parts of the world, there is an increasing interest in searching for growth promoting and immune system-strengthening alternatives. Among the possible alternatives, probiotics, prebiotics, synbiotics (combination of probiotic and prebiotic) and more recently phytogenic products are considered interesting because they have acquired more reliability and acceptability among consumers as safe and natural additives. Scrophularia striata (SS) is a plant which grows in the northeastern part of Iran and their immunomodulatory activities of some species of Scrophularia have also been reported by other investigators. Due to the lack of study for Scrophularia striata effects on broilers performance, and the importance of improving the immune status of broilers, this study was conducted to evaluate the effect of S. striata on male broilers growth performance, heterophil to lymphocyte ratio and immunity; and also to compare them with virginiamycin as a well-documented antibiotic growth-promoter.
    Materials And Methods
    Two-hundred and fifty of one-day-old male (Ross 308) broiler chicks were classified into 25 groups. Each group included 10 chicks (five treatments and five replicates per treatment). The five experimental treatments were as follow: basal diet with no additives (control diet) and basal diet containing virginiamycin antibiotic, synbiotic, 0.4 or 0.8 % SS. Feed intake (FI) and body weight gain (BWG) were recorded in different periods and feed conversion ratio (FCR) was calculated. To study the effects of different treatments on blood leukocyte subpopulations, blood samples of two birds from each replicate were collected from the wing vein at the end of experiment. EDTA-containing blood samples were stained subsequently, 100 leukocytes per samples were counted by an optical microscope. The ratio of heterophil (H) to lymphocyte (L) was calculated. Vaccination was carried out according to the routine regional vaccination program and was based on optimal timing of the maternal antibody level. On 7th and 14th days after last vaccination, blood samples were collected from brachial veins, and the sera were used to determine the humoral immune response derived from vaccination against Newcastle disease and infectious bursal disease. Haemagglutination inhibition tests and enzyme-linked immunosorbent assays were used to determine antibody titers of the chickens against Newcastle disease and infectious bursal disease, respectively. The data were analyzed in a completely randomized design by ANOVA using the General Linear Model (GLM) procedure of SAS Institute.
    Results And Discussion
    The BWG of broilers receiving the antibiotic diet was higher (P
    Keywords: Broiler, Heterophil:lymphocyte, Immune response, Performance, Scrophularia striata
  • Atefeh Seyeddokht, Ali Asghar Aslami Nejad, Morteza Bitaraf Sani Pages 184-190
    Introduction
    Age at first calving (AFC) has an important effect on profitability and reproductive management of dairy cattle. Every month increase in AFC beyond 24 months increases the cost of production. The time between birth and first calving represents a period in which replacement heifers are not generating income. Instead this rearing period requires considerable capital expenditures including feed, housing, and veterinary expenses. These expenses constitute 15% to 20% of the total expenses related to milk production. A basic approach to reduce this cost is to decrease the time between birth and her first freshening. Worldwide recommendations for one particular AFC might be an incorrect management goal for all of the cattle on all of the farms, since the recommendation might not represent the management goals and/or capabilities of a particular production system or farm. We realize that each dairy has its own set of unique management and environmental conditions, which makes a universal AFC and BW after first calving, a difficult goal to achieve. The AFC has a profound influence on the total cost of raising dairy replacements in which older calving heifers are more expensive to raise than younger ones.
    Materials And Methods
    A total of 19499 calving records belonged to 96 herd from 1996 to 2008 were used to estimate genetic components and genetic trend for age at first calving in Holstein dairy cows of Iran. Data were analyzed using a univariate model and Wombat software. Linear regression of estimated breeding values on calving year was used to estimate genetic trend.
    Results And Discussion
    Estimated genetic trend was positive for some years and was negative for others and showed that reducing age at first calving has not been considered in the selection strategies; however, the phenotypic trend was decreased. The age at first calving for Yazd, Markazi, and southern Khorasan provinces were the highest and for Kermanshah, East Azarbayjan, and Ardebil provinces were the lowest compared to the other provinces. Most analysis shows that the financial benefit afforded to heifers that freshen at a low AFC seems to at the least offset any milk lost in the first lactation. The NRC (2001) suggests a post weaning BW equal to 82% of her mature body weight. This can be attained with a maximal pre-pubertal ADG of 2.0 lbs/d if a traditional pre-weaning program is employed or 1.8 lbs/d if an intensified pre-weaning program is employed. Due to the well-defined link between insufficient BW at calving and increased mortality and disease in first calf heifers, attaining this aim post calving BW is of critical importance. Ettema and Santos (2004) conducted an economic analysis of the AFC study that was discussed above. Rearing prices for the medium and high AFC groups were $40.34 and $107.89, respectively, more than that of the low AFC collection. Income for each AFC collection was adjusted for the cost of rearing, assessed feed to increase milk yield, stillbirths, diseases, open days, culling, mortality, labor cost, and the value of milk and calf produced as well as the value of a cow at the end of the 310 day studies. Adjusted income was $119.73 and $9.08 more for the medium and high AFC, respectively, than for the low AFC. These values were not significantly diverse implying no single AFC had an economic benefit over another. Nevertheless, these authors (Ettema and Santos, 2004) did not study the net present value of money in their analysis as St-Pierre (2002) did. If this had been considered, it would presumably shift the economic improvement to the low AFC heifers.
    Conclusion
    Good climatic and weather conditions can be effective factors for reducing the age at first calving and cause to increase the fertility of heifers. However, management methods had a significant effect on this trait in some provinces. The primary benefits of reducing AFC include reducing rearing costs as well as reducing the amount of time in which the heifer is only a capital drain on farm resources. The primary disadvantage of reducing AFC is that it is frequently associated with a reduction in first lactation milk yield. Despite this reduction in first lactation milk yield, production per year of herd life is usually increased by reduced AFC. First lactation may be influenced by AFC, future lactations are definitely not. Furthermore, stay ability and health of cows is not influenced by reduced AFC as long as first calf heifers freshen at an adequate weight.
    Keywords: Age at first calving, Dairy cattle, Genetic trend, Phenotypic trend, Profitability
  • Morteza Bitaraf Sani, Mohammadreza Nassiri, Ali Asghar Aslaminejad, Mohammad Mahdi Shariati Pages 191-198
    Introduction
    Domestic animals are invaluable resources to study the molecular architecture of complex traits. Although the mapping of quantitative trait loci (QTL) underlying economically important traits in domestic animals has achieved remarkable results in recent decades, not all of the genetic variation in the complex traits has been captured due to the low density of markers used in QTL mapping studies. The genome wide association study (GWAS) utilizing high-density single-nucleotide polymorphism (SNP), provides a new way to tackle this issue. Genetic association tests identify differences in allele frequency between cases and controls. Population stratification can be a problem in association studies, such as case-control studies, where the association found could be due to the underlying structure of the population.
    Material And Methods
    In current research, Genome wide association technique (Case-control design) was used to evaluate population stratification. Historical population and genome of 10000 cattle were simulated along 100 generations by Mutation-Drift Equilibrium (MDA) technique. By using historical population, 800 inbred and cross bred cattle with ~50000 SNPs on 30 chromosomes were simulated. Genomic control was performed to survey markers with a low prior probability of association with trait (“null markers”) and to estimate population stratification by Q-Q plot and lambda statistics.
    Results And Discussion
    Deviation of cases/controls ratios between inbred subpopulations causes increasing lambda and population stratification; as lambda was estimated 0.42, 11.31 and 97.77 in additive genetic model with case/control ratios 1.00, 0.77 and 0.33, respectively and 0.47, 8.21 and 57.40 in co-dominant genetic model. Therefore, the more disparate composition cases/controls the more population stratification. When cases and controls were drawn from different randomly mating breeding populations, allele frequencies were different, but these differences may not be related to disease status or complex trait. This means that the assumption of independence of observations is violated. Often this will lead to an overestimation of the significance of an association but it depends on the way the sample is chosen. Population stratification was surveyed between two random groups of crossbred population (400 cases, 400 controls). There was no population stratification among subpopulations of crossbreds in current research; as lambda was estimated 0.55, 0.66, 0.89, 0.76 and 0.41 in co dominant, dominant, recessive, over dominant, additive genetic models, respectively.
    Conclusion
    The main GWAS problem in inbred cattle is population stratification. When cases and controls are drawn from different inbreeding populations, Population Stratification occurs. Lambda and PS is related to Cases/controls ratio among inbred lines, as more deviation ratio of one, more population stratification. It is suggested to control population stratification inbred cattle should not be used unless exactly equal ratio of cases/controls between inbred subpopulations can be achieved and it is better to use of crossbred cattle for genome wide association studies.
    Keywords: Association Studies, Population Stratification, SNPs
  • Zahra Yeganehpour, Hedayat Allah Roshanfekr, Jamal Fayazi, Mir Hasan Beiranvand, Mohammad Ghaderzadeh Pages 199-207
    Inroduction: Inbreeding is defined as the probability that two alleles at any locus are identical by descent and occur when related individuals are mated to each other. The initial consequence of inbreeding is inbreeding depression reducing the performance of growth, production, health, fertility, and survival traits. This concern has become more serious in animal breeding nowadays, in which selection responses are maximized using animal model best linear unbiased predictors (BLUP) of breeding value. The use of these breeding values alone may result in more closely related selection candidates preferred for selection, with increased levels of inbreeding since they share most of their familial information. The unavoidable mating of related animals in closed populations leads to accumulation of inbreeding and decreased genetic diversity. Inbreeding has deleterious effect on additive genetic variance as well as on phenotypic values. Heterozygosity and allelic diversities can be lost from small, closed, selected populations at a rapid rate. The rates of inbreeding must be limited to maintain diversity at an acceptable level so that genetic variation will ensure that future animals can respond to changes in environment. Inbreeding depression has been found in a large proportion of species examined. Lori sheep breed is mainly raised in Lorestan Province in Iran. This study was conducted to identify pedigrees and inbreeding depression on growth traits in Lori sheep population from 2001 to 2010. The rate of inbreeding needs to be limited to maintain diversity at an acceptable level so that genetic variation will ensure that future animals can respond to changes in the environment and to selection. Without genetic variation, animals cannot adapt to these changes.
    Material And Methods
    For this study pedigree information and body weight at different ages (birth weight, weaning weight, 6-month weight, and 9-month weight) of 6440 lambs from 273 rams and 1955 ewes during the years 2001 to 2010 from Lorestan Agricultural and Natural Resources Research Center were used. The pedigree corrections were done by the Excel program and the estimation of inbreeding coefficients was done by pedigree software. To study the pedigree, Pedigree, program, or estimate inbreeding coefficient, CFC program, and for calculate the amount of inbreeding citizenship traits, wombat software were used.
    Results And Discussion
    In total population the number of inbred animals were 2126 (33%) of the herd. The average total population inbreeding coefficient and average inbreeding coefficient inbred of population were 0.69% and 2.24%, respectively. Annual changes in inbreeding coefficient was 0.21, which was statistically significant (p
    Keywords: Animal model, Growth traits, Inbreeding depression, Inbreeding trend, Lori sheep
  • Faeze Ghorbani, Homayon Farhangfar, Nazar Afzali, Mohammad Ebrahim Navidizade Pages 208-217
    Introduction
    Genetic resources in any country are valuable materials which needed to be conserved for a sustainable agriculture. An animal phenotype is generally affected by genetic and environmental factors. To increase mean performance in a population under consideration not only environmental conditions, but also genetic potential of the animals should be improved. Although, environmental improvement could increase the level of animals’ production in a more rapid way, it is not a permanent and non-cumulative progress. In any breeding schemes prediction breeding value of the candidate animals is needed to be obtained with a high precision and accuracy for making a remarkable genetic gain for the traits over the time. The main objective of the present research was to study accuracy of predicted breeding value for body weight at eighth week of age in indigenous chickens of Khorasan Razavi province.
    Materials And Methods
    A set of 47,000 body weight (at the age of eight weeks) records belonging to 47,000 head of male and female chicks (progeny of 753 sires and 5,154 dams) collected during seven generations (2006-2012) was used. The data were obtained in Khorasan Razavi native chicken breeding center. An animal model was applied for analyzing the records. In the model, contemporary group of generation*hatch*sex (GHS) as a fixed effect, weight at birth as a covariable, as well as direct and maternal additive genetic random effects were taken into account. In an initial analysis using SAS software, all fixed and covariate factors included in the model were detected to be significant for the trait. All additive genetic relationships among the animals in the pedigree file (47,880 animals) were accounted for. Variance and covariance components of direct and maternal additive genetic effects were estimated through restricted maximum likelihood (REML) method. Breeding value of the animals was obtained by best linear unbiased prediction (BLUP). Selection accuracy was then calculated based on prediction error variance (PEV). The model was fitted to the data using DMU package. Post analysis of breeding values (genetic trend estimation and statistical comparison of groups using student’s t test) was also undertaken using SPSS software.
    Results And Discussion
    Average and standard deviation of body weight at the age of eight weeks were 607.93 g. and 127.347 g., respectively. As expected, males (668.98 g.) were generally heavier than females (549.86 g.) chickens. Additive and maternal genetic variance components were 3183.9253 and 350.8929, respectively. Based on genetic covariance (-363.8555) the correlation between direct and maternal genetic effects was revealed to be -0.3442. Direct and maternal heritability for the trait were found to be 0.4387 and 0.0483, respectively. Mean direct and maternal breeding values were 76.65 g. and -7.91 g., respectively. The corresponding figures for the direct and maternal accuracies were 0.741 and 0.427, respectively. Genetic trends for direct and maternal breeding value were 26.951 g. (SE=1.344 g.) and -2.252 g. (SE=0.199 g.), respectively and statistically significant (P
    Keywords: Animal model, Body weight, Indigenous chickens, Selection accuracy
  • Abdolreza Jahanbakhshi, Hamidreza Ahmadnia Motlagh, Mahsa Javadi Mousavi, Edris Rahimi Kia Pages 218-224
    Introduction
    Nowadays, the healthiness and high quality as well as quantity of aquatic are of great importance and the role of diet components is well recognized (20). Fish needs energy and nutrients in order to achieve desirable level of growth and development and reproduction (11). In recent years application of immune system stimuli has been widely adopted in order to enhance the immune system of fish and non-specific immune responses and protect against disease. So it seems that using stimulator of the immune system is the perfect solution for the control of aquatic animal diseases. Using chemical drugs and antibiotics in aquaculture have consequences, including the risk of pathogens resistant to these drugs, the drugs persistence in the meat and fish as well as environmental pollution. Taking herbs and medicinal plants such as garlic fraught with same effect as antibiotics can be served as an alternative to medications and antibiotics.
    Materials And Methods
    In this study, 180 gourami fish with average weight 0.10 ± 4.33 were prepared from reproduction and breeding center of ornamental fish in Golestan province. To add the garlic oil to the diets, the standard meal was purchased from commercial fish feed company of Mazandaran province and were ground using a mortar. Then, garlic oil at levels of 0, 0.10, 0.15 and 0.20 g/kg was added to water and mixed. Fish were fed for 8-weeks in three times by 3% body weight per day at hours 8-14-20. Fish diets and their growth rate monitored by conducting bio-survey at the beginning and during the growth for,every 15 days. 10 fish were sampled from each replicate to take serum. After anesthesia using 0.7 ml 2-phenoxyethanol, fish were dried, and about 2 ml of blood was taken by cutting the tail. In hematology laboratory, number of white blood cells, red blood cells, hemoglobin and hematocrit were measured according to standard methods. Glucose levels and serum protein were measured by spectrophotometry using a diagnostic kit (Sigma, America). Data analysis was performed using one-way analysis of variance (ANOVA) in SPSS software. Significant differences (P
    Keywords: Feed Conversion Ratio, Glucose, Hematocrit, Protein