خصوصیات فیزیکی و شیمیایی، فرآسنجه‌های تخمیری تولید گاز، گوارش پذیری نشاسته و ساختار گرانول‌های نشاسته در ذرت ایرانی سینگل کراس 702 و واریته‌های مختلف ذرت‌های تجاری-وارداتی

پژوهشهای علوم دامی ایران

مقاله 4، دوره 13، شماره 1 - شماره پیاپی 45، فروردین 1400، صفحه 43-64   

نوع مقاله: علمی پژوهشی - تغذیه نشخوارکنندگان

شناسه دیجیتال (DOI): 10.22067/ijasr.v13i1.85030

نویسندگان

عطیه رحیمی^{* 1}؛ عباسعلی ناصریان²؛ رضا ولی زاده²؛ عبدالمنصور طهماسبی²؛ حسام دهقانی³

¹گروه علوم دامی،دانشکده کشاورزی، دانشگاه فردوسی مشهد، مشهد، ایران.

²گروه علوم دامی،دانشکده کشاورزی، دانشگاه فردوسی مشهد، مشهد، ایران

³دانشکده دامپزشکی، دانشگاه فردوسی مشهد، مشهد، ایران

چکیده

در این مطالعه ذرت ایرانی واریته سینگل کراس 702 با ذرت‌های تجاری-وارداتی شامل روس، اکراین و برزیل از نظر خصوصیات فیزیکی و شیمیایی، فرآسنجه‌های تخمیری تولید گاز، خصوصیات تجزیه‌پذیری شکمبه‌ای، روده‌ای و کل دستگاه گوارش، میزان آسیب دیدگی و ژلاتیناسیون نشاسته و ساختار گرانول‌های نشاسته مقایسه شدند. ذرت سینگل کراس 702 از نظر شکل ظاهری نسبت به سایر ذرت‌ها کوچکتر بود. وزن حجمی ذرت برزیل نسبت به سایر ذرت‌ها به طور معنی‌داری بالاتر بود. پروتئین، ADF، NDF، نشاسته، NFC، TDN، NE_l و NE_g به طور معنی‌داری در واریته‌های مختلف ذرت متفاوت بودند. نشاسته ذرت سینگل کراس 702 (03/69 درصد) به طور معنی‌داری پایین‌تر از ذرت‌های اکراین (36/70 درصد)، روس (04/71 درصد) و برزیل (49/71 درصد) بود. گاز تجمعی تولید شده در مدت 24 و 48 ساعت در ذرت برزیل، روس و سینگل کراس 702 بالاتر از ذرت اکراین بود. غلظت نیتروژن آمونیاکی و کل اسیدهای چرب فرار در زمان 24 ساعت انکوباسیون تحت تأثیر واریته‌های مختلف ذرت قرار نگرفت. ذرت‌های سینگل کراس 702 و روس قابلیت هضم نشاسته شکمبه‌ای بالاتر و قابلیت هضم نشاسته روده‌ای کمتری نسبت به ذرت‌های اکراین و برزیل داشتند. قابلیت هضم شکمبه‌ای، روده‌ای و کل دستگاه گوارش برای پروتئین خام بین واریته‌های مختلف دانه ذرت اختلاف معنی‌داری نشان نداد. درصد ژلاتیناسیون نشاسته در ذرت روس (24/4 درصد) و سینگل کراس 702 (17/4 درصد) بالاتر از ذرت برزیل (32/3 درصد) و اکراین (78/3 درصد) بود. ذرت سینگل کراس 702 نسبت به سایر ذرت‌ها میانگین مساحت دور هر گرانول، قطر طولی و عرضی و اندازه گرانول‌های نشاسته کمتر و ماتریکس پروتئینی ضعیف‌تری داشت. نتایج این مطالعه نشان داد که ذرت سینگل کراس 702 از لحاظ میزان و نرخ تولید گاز، درصد ژلاتیناسیون و گوارش پذیری نشاسته مشابه با ذرت روس بود.

کلیدواژه‌ها

تولید گاز؛ ذرت سینگل کراس 702؛ ذرت‌های وارداتی؛ ژلاتیناسیون و گوارش پذیری نشاسته

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