补喂脂肪对放牧伊犁马泌乳量、乳成分和血液指标的影响

Effects of fat supplementation on milk yield,milk composition and blood indexes of grazing Yili horses

为探究补喂脂肪对放牧伊犁马泌乳量、乳成分和血液指标的影响,试验选择产驹日期、泌乳期和产奶量相近、生理状况一致伊犁马母马14匹,随机分为2组,分别为精料组和脂肪组,每组7匹马,所有试验马匹均采用放牧+补饲的饲养方式。其中,精料组每天每匹马补喂1 kg精料补充料,脂肪组每天每匹马补喂1 kg精料补充料和400 g脂肪(均衡乳化油粉),一个月后,脂肪增加至600 g,自由饮水,进行为期2个月的试验。结果表明:(1)较精料组,脂肪组马匹泌乳量在整个试验期有显著性提高(P<0.05)。(2)精料组和脂肪组的乳脂率、乳蛋白率、乳糖率、总固体、体细胞数、非脂固形物和尿素氮等指标间均无显著性差异(P>0.05)。(3)脂肪组马乳月桂酸、亚油酸显著高于精料组(P<0.05),然而精料组十五碳酸、棕榈一烯酸、十七烷酸一烯酸和γ-亚麻酸显著高于脂肪组(P<0.05)。(4)第20、40天和60天饲喂前0 h和饲喂后2 h精料组和脂肪组的葡萄糖、甘油三酯和胰岛素浓度均无显著性差异(P>0.05);第20天饲喂后2 h和第60天饲喂后2 h脂肪组马匹血浆高密度脂蛋白显著高于精料组(P<0.05);试验第40天,脂肪组伊犁马血浆游离脂肪酸浓度在饲喂前0 h和饲喂后2 h均显著高于精料组(P<0.05)。(5)第20、40天和60天饲喂前0 h和饲喂后2 h精料组和脂肪组的过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化歧化酶(SOD)活力和丙二醛(MDA)浓度均无显著性差异(P>0.05)。综上所述,补喂脂肪可提高放牧伊犁马泌乳量、乳脂产量、乳中月桂酸和亚油酸含量以及机体对脂肪酸的吸收利用,而对马乳成分、机体抗氧化能力没有影响。

This experiment was to explore the effects of fat supplementation on milk yield,milk composition and blood indexes of grazing Yili horses.Fourteen Yili horses with similar foal date,lactation period and milk yield were randomly divided into two groups:concentrate group(n=7)and fat group(n=7).All the experimental horses were fed with grazing and supplementary feeding.Among them,the concentrate group was fed with 1 kg concentrate supplement every day,and the fat group was fed with 1 kg concentrate supplement and 400 g fat(balanced emulsified oil powder)every day.One month later,the fat was increased to 600 g and drank freely for a period of 2 months.The results showed that:(1)The milk yield of the fat group was significantly higher than that of the concentrate group(P<0.05).(2)There was no significant difference in milk fat rate,milk protein rate,lactose rate,total solids,somatic cell count,non-fat solids and urea nitrogen between concentrate group and fat group(P>0.05).(3)Horse milk lauric acid and linoleic acid in fat group were significantly higher than those in concentrate group(P<0.05),but pentadecanoic acid,palmitoenoic acid,heptadecanoic acid andγ-linolenic acid in concentrate group were significantly higher than those in fat group(P<0.05).(4)There was no significant difference in the concentrations of glucose,triglyceride and insulin between the concentrate group and the fat group at 0 h before and 2 h after feeding on the 20,40,60 days(P>0.05).The plasma high density lipoprotein in the fat group was significantly higher than that in the concentrate group at 2 hours after feeding on the 20,60 days(P<0.05).On the 40 days of the experiment,the plasma free fatty acid concentration of Yili horse in the fat group was significantly higher than that in the concentrate group at 0 hours before feeding and 2 hours after feeding(P<0.05).(5)There was no significant difference in catalase,glutathione peroxidase,superoxide dismutase activity and malondialdehyde concentration between concentrate group and fat group at 20,40,60 days before feeding and2 hours after feeding(P>0.05).To sum up,the supplementation of fat could increase the milk yield,milk fat yield,the content of lauric acid and linoleic acid in milk and the absorption and utilization of fatty acids,but had no effect on the composition of horse milk and the ability of antioxidation.