日粮添加不同水平粗甘油对乳山羊泌乳性能、养分消化及乳成分的影响

Effects of dietary supplementation of different levels of crude glycerin on lactation performance,nutrient digestion and milk composition of milk goats

文章旨在评估日粮添加不同水平粗甘油对乳山羊泌乳性能、养分消化及乳成分的影响。试验将平均体重为(48.67±2.76)kg、泌乳期为(58±9.5)d的72头乳山羊随机分为3组,每组6个重复,每个重复4头。对照组饲喂基础浓缩日粮,T1和T2组饲喂粗甘油水平为1%和2%的浓缩日粮。经过为期6周的饲养试验后测定相关指标。结果发现,与对照组相比,T1组乳脂肪和总固形物产量分别显著提高12.48%和4.61%(P<0.05),乳蛋白质产量显著降低9.88%(P<0.05)。日粮添加不同水平的粗甘油对乳山羊有机物粗蛋白质、中性洗涤纤维和酸性洗涤纤维表观消化率的影响均无显著差异(P>0.05)。与对照组相比,T1组干物质表观消化率显著提高7.99%(P<0.05),而T1和T2组粗脂肪表观消化率分别显著提高5.17%和3.45%(P<0.05)。T2组乳脂肪含量较对照组显著提高13.62%(P<0.05),而T1和T2组乳中不饱和脂肪酸含量较对照组分别显著降低13.42%和11.94%(P<0.05)。结论:在本研究条件下,粗甘油对乳山羊产奶量及乳脂肪酸含量无负面影响,其中1%粗甘油可以提高乳总固形物含量、干物质及粗脂肪表观消化率。

This experiment was conducted to evaluate the effects of different levels of crude glycerol supplementation on lactation performance,nutrient digestion and milk composition of dairy goats.Seventy-two lactating goats with an average body weight of(48.67±2.76)kg and a lactation period of(58±9.5)days were randomly divided into 3 groups with 6 replicates per group and 4 goats per replicate.The piglets in control group were fed a basal concentrate diet,and the piglets in T1 and T2 groups were fed diets with 1%and 2%crude glycerol in the concentrate diet.After 6 weeks of feeding experiment,the related indexes were determined.Results:Compared with control group,milk fat and total solid yield in T1 group were significantly increased by 12.48%and 4.61%(P<0.05),respectively,while milk protein yield was significantly decreased by 9.88%(P<0.05).There were no significant differences in the apparent digestibility of organic crude protein,neutral detergent fiber and acid detergent fiber of dairy goats supplemented with different levels of crude glycerol(P<00.05).Compared with the control group,the apparent digestibility of dry matter in T1 group was significantly increased by 7.99%(P<0.05),while the apparent digestibility of ether extract in T1 and T2 groups was significantly increased by 5.17%and 3.45%(P<0.05),respectively.Compared with the control group,the milk fat content in T2 group was significantly increased by 13.62%(P<0.05),while the milk unsaturated fatty acid content in T1 and T2 groups was significantly decreased by 13.42%and 11.94%(P<0.05),respectively.Conclusions:Under the conditions of this study,crude glycerol has no negative effects on milk yield and milk fatty acid content of dairy goats,and 1%crude glycerol can increase the total solid content,dry matter and apparent digestibility of crude fat in milk.