کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10974237 | 1108023 | 2015 | 16 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The effect of high and low levels of supplementation on milk production, nitrogen utilization efficiency, and milk protein fractions in late-lactation dairy cows
ترجمه فارسی عنوان
تاثیر سطوح بالا و پایین مکمل بر تولید شیر، بهره وری مصرف نیتروژن و درصد پروتئین شیر در گاوهای لبنی دیر هنگام شیردهی
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کلمات کلیدی
تغذیه، چمن سیلیکات، چمن، تمرکز، نیتروژن، پروتئین شیر
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
علوم دامی و جانورشناسی
چکیده انگلیسی
To fill the feed deficit in the autumn/late lactation period in a seasonal grazing system, supplementation is required. This study aimed to investigate the use of baled grass silage or concentrate as supplementation to grazing dairy cows in late lactation. Eighty-four grass-based spring-calving dairy cows, averaging 212Â d in milk, were allocated to 1 of 6 treatments [high grass allowance (HG), low grass allowance (LG), grass with a low concentrate allocation (GCL), grass with a low grass silage allocation (GSL), grass with a high concentrate allocation (GCH), and grass with a high grass silage allocation (GSH)] to measure the effects of using baled grass silage or concentrate as supplements to grazed grass. Effects on intake, milk yield, milk composition and N fractions, and N utilization efficiency were measured. Treatments HG and LG received 17 and 14Â kg of dry matter (DM) grass/cow per d, respectively. Treatments GCL and GSL were offered 14Â kg of DM grass/cow per d and 3Â kg of DM of supplementation/cow per d. Treatments GCH and GSH were offered 11Â kg of DM grass/cow per d and 6Â kg of DM of supplementation/cow per d. Milk yield was greatest in the GCH treatment and milk solids yield was greatest in both concentrate-supplemented treatments. The HG and LG treatments excreted a greater quantity of N as a proportion of N intake than the supplemented treatments. The HG treatment also excreted the greatest total quantity of N. This indicates an improvement in N utilization efficiency when supplementation is offered compared with grazing only. Offering 6Â kg of DM of either grass silage or concentrate as supplementation decreased milk true protein concentration compared with offering a grass-only diet. This suggests that increasing the proportion of supplementation relative to grass may negatively affect milk processability, which is associated with milk true protein concentration.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Dairy Science - Volume 98, Issue 8, August 2015, Pages 5529-5544
Journal: Journal of Dairy Science - Volume 98, Issue 8, August 2015, Pages 5529-5544
نویسندگان
M. Reid, M. O'Donovan, J.P. Murphy, C. Fleming, E. Kennedy, E. Lewis,