اثر سطوح مختلف پنبه‌دانه كامل بر توليد، تركيبات شير، قابليت هضم و فراسنجه‌هاي خوني در گاو شيري نژاد مونت بيليارد

Effect of Different Levels of Whole Cottonseed on Production, Milk Composition, Digestibility and Blood Parameters of Montebeliard Breed Lactating Cows

این آزمایش به منظور بررسی اثرات سطوح مختلف پنبه‌دانه بر عملكرد، تركیب شیر، قابلیت هضم ماده خشك و فراسنجه‌های خونی گاوهای شیری نژاد مونت بیلیارد در اوایل دوره شیر‌دهی انجام شد. بدین منظور از 16رأس گاو شیری مونت بیلیارد در 4 تیمار با 4 تكرار، در قالب طرح كاملاً تصادفی استفاده شد. تیمار‌های آزمایشی شامل تیمار شاهد (صفر درصد پنبه‌دانه) و سه سطح مختلف پنبه‌دانه شامل 7، 14 و 21 درصد در جیره بود. همه جیره‌های كاملاً مخلوط به صورت انفرادی تا حد اشتها (به طور آزاد) به دام‌ها داده شده و گاوها 2 بار در روز دوشیده شدند. نمونه‌گیری از شیر به طور هفتگی انجام شد. به منظور اندازه‌گیری فراسنجه‌های خونی (گلوكز، كلسترول، تری‌گلیسرید، نیتروژن اوره‌ای)، خونگیری از سیاهرگ دمی گاوها انجام گرفت. تولید شیر خام بر اساس ضریب 4 درصد چربی شیر تصحیح شده و تركیبات شیر و قابلیت هضم ماده خشك خوراك بررسی شد. تولید شیر خام در جیره‌های حاوی پنبه‌دانه نسبت به جیره بدون پنبه‌دانه (شاهد) به طور معنی‌داری افزایش یافت. در میان جیره‌های حاوی پنبه‌دانه، با افزایش درصد پنبه‌دانه در جیره درصد چربی شیر گاوها به طور معنی‌داری افزایش یافت. ماده خشك مصرفی و قابلیت هضم ماده خشك جیره درگاوهای تغذیه شده با جیره‌های1 تا 4 تفاوت معنی‌داری را نشان داد. با افزایش مقدار پنبه‌دانه در جیره شاهد مقدار گلوكز كاهش و میزان كلسترول، تری‌گلیسرید و نیتروژن اوره‌ای خون به طور معنی‌داری افزایش یافت. نتایج تحقیق حاضر نشان داد افزودن پنبه‌دانه كامل به جیره غذایی به میزان 14 و 21 درصد می‌تواند تولید شیر، درصد چربی شیر و درصد مواد كل جامد شیر را افزایش دهد.

Introduction This experiment was conducted to investigate the effects of different level of whole cotton seed on performance, milk composition, dry matter digestibility and blood parameters of Montebeliard cows at first milking period. Whole cottonseed (WCS) is an unusual feedstuff for ruminants. Due to its high content of fat and protein, it may be defined as a concentrate. On the other hand, its fiber is similar to that of forages in terms of effectiveness in the rumen. The response of dairy cattle milk production to WCS feeding is variable. A large part of the effect of WCS on milk production is related to ruminal effects, which depend upon the basal diet fermentation balance. Montbéliarde cattle are a red and white pied cattle breed from the Montbéliard region of France, used mainly for dairying and particularly for cheese making. Materials and Methods This research project was conducted at Behkadeh Razavi Corporation, Bojnourd, North province and department Animal Science Gorgan University of Agricultural Sciences and Natural Resources, Iran. In this experiment 16 Montebeliard dairy cows were used in a completely random design with 4 treatments and 4 cows per each treatment during 30 days (14 day adaptation and 16 day sampling). Each treatment received whole cottonseed according their group (0 % (control), 7, 14 and 21% respectively). Cows were milking 2 times in each day and sampling of milk was done weekly. The average milk production and body weight cows before experiment were 24.8±3kg day-1 and 840±30kg. Samples were collected from tail vein for blood parameters (glucose, cholesterol, TG and BUN) in last day. Milk production corrected with 4% fat coefficient. The 3 days end experiment collection of samples of feces used for apparent digestibility of dry matter. The AIA content of the feed and the excreta were determined Results and Discussion Over the experimental periods, production of raw milk in the diets with whole cotton seed were greater significantly than control group (P <0.05). Means of milk fat percent was increased significantly via increasing the amount of whole cottonseed (P <0.05) but there weren’t any significant different between the means of lactose, milk solid mass without fat and percent of milk protein in treatment. DMI and digestibility of dry matter between treatments were significantly (P <0.05). By increasing the amount of whole cotton seed in diets, amount of glucose were decreased but TG and BUN increased. Results of present experiment showed, by increasing the amount of whole cotton seed in dairy cows diets to 14 and 21%, milk production, milk fat percent and total milk solid mass would be increase. Conclusion The important results we found in this experiment that addition cottonseed 14 and 21 percent of cottonseed in the diet improves the production of milk and fat percentage milk. Also, blood metabolites such as glucose, triglyceride, cholesterol and blood urea nitrogen did affected by treatment. This experiment was conducted to investigate the effects of different level of whole cotton seed on performance, milk composition, dry matter digestibility and blood parameters of Montebeliards cows at first milking period. Materials and Methods: In this experiment 16 Montebeliards dairy cow were used in a completely random design with 4 treatment and 4 cow per each treatment during 30 days (14 day adaptation and 16 day sampling). Each treatments received whole cottonseed according their group (0 % (control), 7, 14 and 21% respectively). Cows were milking 2 times in each day and sampling of milk were done weekly. Samples were collected from tail vein for blood parameters (glucose, cholesterol, TG and BUN) in last day. Milk production corrected with 4% fat coefficient. Results and Discussion: Over the experimental periods, production of raw milk in the diets with whole cotton seed were greater significantly than control group (P <0.05). Means of milk fat percent was increased significantly via increasing the amount of whole cottonseed (P <0.05) but there weren’t any significant different between the means of lactose, milk solid mass without fat and percent of milk protein in treatment. DMI and digestibility of Dry matter in the cows between treatment were significantly (P <0.05). By increasing the amount of whole cotton seed in diets, amount of glucose were decreased but TG and BUN increased. Results of present experiment showed, by increasing the amount of whole cotton seed in dairy cows diets to 14 and 21%, milk production, milk fat percent and total milk solid mass would be increase