泌乳盛期和泌乳后期奶牛的采食行为和日粮营养物质表观消化率的对比分析

试验旨在研究不同泌乳阶段奶牛饲喂相同日粮对采食行为和日粮营养物质表观消化率的影响。选择体重、胎次相近的8头健康泌乳牛,其中4头处于泌乳盛期(泌乳盛期组),4头处于泌乳后期(泌乳后期组),2组奶牛饲喂相同日粮,预试期15 d,正试期15 d。结果表明:泌乳盛期组奶牛每天干物质采食量(24.0 kg)高于泌乳后期组(P<0.01),泌乳盛期组奶牛每千克干物质的采食时间、一昼夜总反刍时间、躺卧时间均低于泌乳后期组(P<0.01),;泌乳盛期组奶牛日粮中中性洗涤纤维和酸性洗涤纤维的表观消化率低于泌乳后期组(P<0.01)。由此可见,泌乳盛期奶牛采食时间极显著高于泌乳后期奶牛,泌乳盛期奶牛躺卧时间极显著少于泌乳后期。

Comparison of Feeding Behavior and Digestibility of Fibrous Nutrients in Dairy Cows at Different Lactation Stages

Eight lactating cows with similar body weight and parity were selected in this experiment for comparison of the effect of feeding the same diet on feeding behavior and apparent digestibility of dietary nutrients in dairy cows at different lactation stages. Four cows were in the high lactation stage(the high lactation stage group) and four cows were in the late lactation stage(the late lactation group). All cows were fed with the same diet for 15 days in preliminary trial period and 15 days in the trial period. The results showed that the daily feed intake was 24.0 kg DM in the high lactation group, which was significantly higher than that in the late lactation group(16.8 kg DM, P<0.01). The feeding time per kilogram of DM in high lactation group was significantly lower than that in late lactation group(P<0.01). The total rumination time in the day and night was significantly lower in the high lactation group than in the late lactation group(P<0.01). The lying time of dairy cows in the high lactation period was significantly shorter than that in the late lactation period(P<0.01). The apparent digestibility of NDF and ADF in the diet of dairy cows in the high lactation period was significantly lower than that in the late lactation period group(P<0.01). This result demonstrated that the feeding time of dairy cows in high lactation period was significantly longer than that in late lactation period, and the lying time of dairy cows in high lactation period was significantly less than that in late lactation period.