腐殖酸钾对泌乳奶牛生产性能、血清生化和营养物质表观消化率的影响

Effect of Potassium Humate on Productive Performance,Serum Biochemistry and Apparent Digestibility of Nutrients in Lactating Dairy Cows

试验旨在探究日粮中添加不同水平腐殖酸钾对泌乳奶牛生产性能、牛乳质量、血清生化指标以及营养物质表观消化率的影响。选取体重接近[(520±30)kg]且健康的泌乳母牛12头,按照体重、产奶量和泌乳天数相似原则分为4组,分别为对照组(基础日粮组)、试验Ⅰ组(基础日粮+2 g·kg^(-1)的腐殖酸钾)、试验Ⅱ组(基础日粮+4 g·kg^(-1)的腐殖酸钾)和试验Ⅲ组(基础日粮+8 g·kg^(-1)的腐殖酸钾),试验期60 d。结果表明:(1)试验Ⅱ组和试验Ⅲ组奶牛干物质采食量和日产奶显著高于对照组和试验Ⅰ组(P<0.05);添加腐殖酸钾可显著改善牛乳品质(P<0.05),其中日粮中添加4 g·kg^(-1)及以上腐殖酸钾牛乳品质显著提高(P<0.05),牛乳品质中的校正乳产量、乳蛋白产量、乳脂产量、总乳固形物、乳蛋白率和乳脂率均得到一定程度改善。(2)添加不同水平腐殖酸钾对泌乳奶牛血清生化指标均无显著影响(P>0.05)。(3)日粮中添加4 g·kg^(-1)以上腐殖酸钾可显著提高粗蛋白、酸性洗涤纤维、中性洗涤纤维和钙的表观消化率(P<0.05),添加8 g·kg^(-1)的腐殖酸钾可显著改善泌乳奶牛干物质表观消化率(P<0.05),日粮中添加不同水平腐殖酸钾均可改善磷表观消化率(P<0.05)。综上,日粮中添加4 g·kg^(-1)以上的腐殖酸钾会改善泌乳奶牛平均日采食量、产奶量和乳液品质,提高奶牛营养物质表观消化率,且对血液生化指标无负面影响。

This experiment aimed to investigate the effects of adding different levels of potassium humate to the diet of lactating cows on production performance,milk quality,serum biochemical parameters,and apparent digestibility of nutrients.A total of 12 healthy lactating cows with body weight close to[(520±30)kg]were selected and divided into four groups according to the similarity of body weight,milk yield and lactation days as the followings:the control group(primary diet group),the test groupⅠ(essential diet+2 g·kg^(-1) of potassium humate),the test groupⅡ(important diet+4 g·kg^(-1) of potassium humate)and the test groupⅢ(essential diet+8 g·kg^(-1) of potassium humate).The experiment period was 60 days.The results showed that(i)the average daily feed intake and lactation of cows in the test groupⅡand the test groupⅢwere significantly higher than those in the control and the test groupⅠ(P<0.05);the addition of potassium humate significantly improved milk quality(P<0.05),with the addition of 4 g·kg^(-1) or more of potassium humate to the diet significantly improving milk quality(P<0.05),and milk quality in terms of corrected milk yield,milk protein yield,fat milk yield,the total milk solids,milk protein rate,and fat milk rate were all improved to some extent.(ii)The addition of different levels of potassium humate to diet had no significant effect on the serum biochemical indexes of lactating cows(P>0.05).(iii)Addition of 4 g·kg^(-1) or more of potassium humate to the diet significantly improved the apparent digestibility of crude protein,acid detergent fiber,neutral detergent fiber,and calcium(P<0.05),and the addition of 8 g·kg^(-1) of potassium humate significantly improved the apparent digestibility of dry matter in lactating cows(P<0.05).The addition of different levels of potassium humate to the diet improved the apparent digestibility of phosphorus(P<0.05).In conclusion,adding potassium humate at 4 g·kg^(-1) or more to the diet improved the average daily feed intake,milk yield,and milk quality of lactating cows.It improved the apparent digestibility of nutrients in cows with no adverse effect on blood biochemical parameters.