کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2096921 1082184 2006 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Conception rate and reproductive function of dairy cows fed different fat sources
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Conception rate and reproductive function of dairy cows fed different fat sources
چکیده انگلیسی

The objective of the experiment was to determine the effects of fat supplementation on cyclicity, progesterone concentration, follicular development, conception rate, embryo mortality, and plasma concentrations of prostalglandin F metabolite (PGFM) in cattle. The hypothesis of this experiment was that feeding flaxseed, which is a source rich in C18:3, would increase conception rate of dairy cows due to decreased plasma PGFM concentrations. A total of 138 lactating Holstein cows were allotted at calving to three groups of 46 cows, blocked for similar calving dates. Cows within each block were assigned to one of three isonitrogenous, isoenergetic, and isolipidic supplements based on either whole flaxseed (FLA), Megalac® (MEG) or micronized soybeans (SOY). The diets were fed from calving to Day 50 of pregnancy for pregnant cows, or 120 day postpartum for those not diagnosed pregnant after AI. Detailed measurements of PGFM and follicle dynamics were only made on four cows for FLA and five cows for both MEG and SOY. The response in PGFM concentration following the oxytocin challenge administered around Week 11 of lactation was similar over time among treatments. Plasma progesterone concentrations from Days 17 to 21 of the estrous cycle starting around Week 9 of lactation and determined on a subsample of cows (n = for FLA and n = 5 for both MEG and SOY) were higher for cows fed FLA than for those fed SOY (P = 0.04) or MEG (P = 0.06). Conception rates were similar among treatments. Total embryo mortality was lower (P = 0.07) for cows fed FLA (0%) compared to those fed either MEG (15.4%) or SOY (8.0%). The mean size of the CL measured during a complete estrous cycle from Week 9 of lactation was smaller for cows fed SOY (16.3 mm) compared to those fed either FLA (19.1 mm) or MEG (18.3 mm). We inferred that pregnancy losses could be reduced by feeding whole flaxseed as a result of its effects on different factors such as modulation in concentration of progesterone and size of the CL.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Theriogenology - Volume 66, Issue 5, 15 September 2006, Pages 1316–1324
نویسندگان
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