日粮添加包被尿素对乳山羊泌乳性能、乳成分及瘤胃发酵参数的影响

Effects of dietary coated urea on lactating performance,milk composition and rumen parameters of dairy goats

文章旨在评估日粮添加包被尿素替代豆粕对乳山羊泌乳性能、养分摄入、乳成分及瘤胃发酵参数的影响。试验将32头平均泌乳期为(68±3)d的乳山羊随机分为2组,每组16头,每组8个重复(2头/重复)。对照组饲喂玉米-青贮玉米-豆粕型全混合日粮,处理组饲喂用30%包被尿素替代豆粕的全混合日粮,饲养试验持续5周。结果:日粮添加30%包被尿素替代豆粕显著提高了乳山羊干物质、粗灰分、有机物、粗蛋白质、粗脂肪、中性洗涤纤维和酸性洗涤纤维摄入量(P<0.05),但处理组泌乳量和4%脂肪校正乳较对照组分别显著降低4.12%和4.46%(P<0.05)。两组乳山羊蛋白质、乳糖和非脂固形物产量无显著差异(P>0.05)。与对照组相比,包被尿素组乳山羊脂肪和总固形物含量分别显著提高12.30%和4.88%(P<0.05)。与对照组相比,包被尿素组乳山羊瘤胃pH显著降低3.80%(P<0.05),但乙酸与丙酸比值显著提高6.01%(P<0.05)。结论:在本试验条件下,日粮添加30%包被尿素替代豆粕提高了乳山羊的养分摄入量及乳中脂肪和总固形物含量,但降低了泌乳量。包被尿素对瘤胃大部分发酵参数无负面影响。

The objective of this study was to evaluate the effects of supplementing with coated urea instead of soybean meal on lactation performance,nutrient intake,milk composition and rumen fermentation parameters of dairy goats.Thirtytwo lactation goats with an average lactation period of 68±3 days were randomly divided into 2 groups with 16 goats per group and 8 replicates per group(2 goats/replicate).The control group was fed a corn-silage corn-soybean meal total mixed diet,and the treatment group was fed a 30%urea coated total mixed diet instead of soybean meal.The feeding experiment lasted for 5 weeks.Results:Dietary supplemented with 30%coated urea instead of soybean meal significantly increased the intake of dry matter,ash,crude protein,ether extract,neutral detergent fiber and acid detergent fiber of dairy goats(P<0.05),but milk yield and 4%fat corrected milk in treatment group were significantly decreased by 4.12%and 4.46%compared with control group(P<0.05),respectively.There were no significant differences in daily output of protein,lactose and non-fat solids between the two groups(P>0.05).Compared with the control group,the daily fat and total solid yields of dairy goats in urea coated group were significantly increased by 12.30%and 4.88%(P<0.05),respectively.Compared with the control group,rumen pH value in urea coated group was significantly decreased by 3.80%(P<0.05),but the ratio of acetic acid to propionic acid was significantly increased by 6.01%(P<0.05).Conclusion:In this study,the supplementation of 30%coated urea instead of soybean meal increased nutrient intake and milk fat and total solid contents,but decreased milk yield of dairy goats.Coated urea had no negative effect on most rumen fermentation parameters.