Milk production and composition, ovarian function, and prostaglandin secretion of dairy cows fed omega-3 fats
Milk production and composition, ovarian function, and prostaglandin secretion of dairy cows fed omega-3 fats
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DOI：
10.3168/jds.s0022-0302(02)74147-7
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发表时间：
2002-04-01
影响因子：
3.5
通讯作者：
Mann, GE
中科院分区：
文献类型：
--
作者：
Petit, HV;Dewhurst, RJ;Mann, GE
在4 × 4拉丁方实验中使用4头经产荷斯坦奶牛，研究富含ω-3脂肪酸的脂肪源对产奶量和成分、卵泡发育和前列腺素分泌的影响。所有奶牛饲喂含有60%青贮饲料和40%精料的混合日粮。四种处理是基于Megalac、经脱甲酰胺处理的全亚麻籽、鱼油和经脱甲酰胺处理的全亚麻籽的混合物（50：50，油基）的浓缩物，或者浓缩物中没有脂肪源但每天将500 g亚麻籽油注入十二指肠。采食量和产奶量在各处理间相似。一般而言，对于经甲酰胺处理的整个亚麻籽处理，观察到最低的消化率。饲喂鱼油降低了乳脂和蛋白质的百分比。α-亚麻酸从1.0%增加到13.9%的牛奶脂肪酸与亚麻籽油输液。这证实了将α-亚麻酸掺入乳中的高潜力，并表明甲醛处理对限制瘤胃中的生物氢化作用很小。增加对这些奶牛的α-亚麻酸供应不会导致牛奶中二十碳五烯酸浓度的增加。接受甲氨蝶呤处理的亚麻籽和鱼油的奶牛血浆中13，14-二氢-15-酮-PGF（2 α）水平较高。这种代谢产物在催产素激发后的增加，对于给予亚麻籽作为饮食中唯一的油补充剂或作为亚麻籽油的十二指肠输注的奶牛，倾向于较低。卵泡动力学相似的治疗。较大的黄体（CL）被发现与奶牛接受高水平的ω-3脂肪酸通过饮食作为甲醛处理的亚麻籽或作为甲醛处理的亚麻籽和鱼油的混合物，虽然CL较小时，奶牛注入亚麻籽油到十二指肠。这些结果表明，在早期的工作中，当喂食增加水平的α-亚麻酸时，观察到妊娠率的改善，部分原因可能是二烯前列腺素PGF（2 α）的生产水平较低。
Four multiparous Holstein cows were used in a 4 x 4 Latin square experiment to study the effects of fat sources rich in omega-3 fatty acids on milk production and composition, follicular development, and prostaglandin secretion. All cows were fed a total mixed diet containing 60% grass silage and 40% concentrate. The four treatments were concentrates based either on Megalac, formaldehyde-treated whole linseed, a mixture (50:50, oil basis) of fish oil and formaldehyde-treated whole linseed, or no fat source in the concentrate but with 500 g per day of linseed oil being infused into the duodenum. Feed intakes and milk yield were similar among treatments. In general, the lowest digestibility was observed for the formaldehyde-treated whole linseed treatment. Feeding fish oil decreased milk fat and protein percentages. Alpha-linolenic acid increased from 1.0 to 13.9% of milk fatty acids with linseed oil infusion. This confirms the high potential to incorporate a-linolenic acid into milk, and suggests that the formaldehyde treatment had little effect to limit biohydrogenation in the rumen. Increasing the supply of alpha-linolenic acid to these cows did not result in an increase in the concentration of eicosapentaenoic acid in milk. Levels of 13,14-dihydro-15-keto-PGF(2alpha),, in plasma were higher for cows receiving formaldehyde-treated linseed and fish oil. Increases in this metabolite in response to oxytocin challenge, tended to be lower for cows given linseed either as sole oil supplement in the diet or as a duodenal infusion of linseed oil. Follicle dynamics were similar among treatments. Larger corpora lutea (CL) were found with cows that received high levels of omega-3 fatty acids through the diet as formaldehyde-treated linseed or as a mixture of formaldehyde-treated linseed and fish oil, although CL were smaller when cows were infused with linseed oil into the duodenum. These results suggest that the improvement in gestation rate that was observed when feeding increased levels of alpha-linolenic acid in earlier work may partly result from lower levels of production of the dienoic prostaglandin PGF(2alpha).