Flipot P M, Roy G L, Dufour J J
Agriculture Canada Research Station, Lennoxville, Quebec.
J Dairy Sci. 1988 Jul;71(7):1840-50. doi: 10.3168/jds.S0022-0302(88)79753-2.
Ninety multiparous Holstein cows were used to measure the effect of energy during the prepartum and postpartum periods. During the prepartum period (63 d) half of the cows were fed grass silage ad libitum and a concentrate (16% protein) was offered daily at .25% of BW. The other half of the cows were offered the silage ad libitum but concentrate at .75% of BW. At calving each of the two prepartum groups was subdivided into three subgroups and fed corn silage for ad libitum consumption, 4.5 kg of hay/d and concentrate (20% protein) at .25 or .75% of BW daily, or ad libitum. After 112 d of lactation, all cows were switched to a diet consisting of corn silage fed ad libitum and 1 kg of concentrate (20% protein)/4 kg of milk. Roughage intake was reduced with an increase of concentrate consumption. Body measurements, calf weight, milk yield, feed efficiency, services per conception, and incidence of diseases were not influenced by the prepartum regimen. However, the interval from parturition to conception was 24 d longer for cows on the higher prepartum energy concentration (.75% of BW). None of the cows was able to meet its nutrient requirement in early lactation. Milk yield increased with each increment of concentrate in the postpartum diet. Reproduction and health were not affected by the postpartum regimen.
选用90头经产荷斯坦奶牛来测定产前和产后能量的影响。在产前阶段（63天），一半奶牛自由采食青贮牧草，每天按体重的0.25%提供精饲料（蛋白质含量16%）。另一半奶牛自由采食青贮饲料，但精饲料按体重的0.75%提供。产犊时，两个产前组各自再细分为三个亚组，分别自由采食玉米青贮饲料、每天采食4.5千克干草以及按体重的0.25%或0.75%每天提供精饲料（蛋白质含量20%），或者自由采食。泌乳112天后，所有奶牛都改为采食由自由采食的玉米青贮饲料和每4千克牛奶搭配1千克精饲料（蛋白质含量20%）组成的日粮。随着精饲料采食量增加，粗饲料采食量减少。产前饲养方案对体尺测量、犊牛体重、产奶量、饲料效率、每次受孕的配种次数和疾病发生率均无影响。然而，产前能量浓度较高（体重的0.75%）的奶牛从分娩到受孕的间隔时间长24天。没有一头奶牛在泌乳早期能够满足其营养需求。产后日粮中精饲料每增加一次，产奶量就会增加。产后饲养方案对繁殖和健康没有影响。
