PEGASE, INRA Agrocampus Ouest, 16 Le Clos, F-35590 Saint-Gilles, France.
FERLUS, INRA, Les Verrines, F-86600 Lusignan, France.
Animal. 2019 Nov;13(11):2492-2500. doi: 10.1017/S1751731119000703. Epub 2019 May 14.
Grazing management has an important impact on dairy ruminants' performance. References on the intake and milk yield of dairy goats under strip-grazing systems in temperate regions are scarce. In order to study the effect of pasture allowance on pasture intake (PI), milk yield and grazing behaviour, a trial was carried out in spring with 36 Alpine goats in mid-lactation. Three daily pasture allowances (PA=1.7, 2.6 and 3.5 kg dry matter (DM)/day, namely Low, Medium and High, respectively) were compared in a 3 × 3 Latin square design replicated six times during three successive 14-day periods. Goats individually received 268 g DM of concentrate twice daily at each milking and had access 11 h/day to pasture (from 0830 to 1600 h and from 1730 to 2100 h). Pasture intake increased with PA, and more so between Low and Medium than between Medium and High (+216 v. +101 g DM/kg DM of PA). Milk yield was lower on Low than on Medium and High (2.79 v. 3.13 kg/day), as were milk fat and protein yields. Grazing time averaged 476 min/day and was lowest on Low and greatest on Medium. Pasture intake rate was 30 g DM/h lower on Low and Medium than on High. It is concluded that under temperate conditions, when goats are supplemented with 536 g DM of concentrate and have enough access time to pasture (11 h/day), a medium pasture allowance close to 2.6 kg DM/day may be sufficient to maximise milk yield.
放牧管理对奶牛反刍动物的性能有重要影响。关于在温带地区进行条牧的奶山羊的采食量和产奶量的参考文献很少。为了研究牧草允许量对牧草采食量（PI）、产奶量和放牧行为的影响，在春季对 36 只泌乳中期的阿尔卑斯山羊进行了试验。在三个连续的 14 天期间，进行了 3×3 拉丁方设计的 6 次重复试验，比较了三种每日牧草允许量（PA=1.7、2.6 和 3.5kg 干物质（DM）/天，分别为低、中、高）。山羊每天在两次挤奶时单独接受 268gDM 的浓缩物，并每天 11 小时放牧（从 0830 到 1600 小时和从 1730 到 2100 小时）。随着 PA 的增加，牧草采食量增加，低与中之间的增加幅度大于中与高之间的增加幅度（+216v.+101gDM/kgDMPA）。低 PA 组的产奶量低于中 PA 和高 PA 组（2.79v.3.13kg/天），乳脂和乳蛋白产量也是如此。平均放牧时间为每天 476 分钟，低 PA 和中 PA 组最低，中 PA 组最高。低 PA 和中 PA 组的牧草采食量比高 PA 组低 30gDM/h。结论是，在温带条件下，当山羊补充 536gDM 的浓缩物并有足够的放牧时间（每天 11 小时）时，接近 2.6kgDM/天的中等牧草允许量可能足以最大限度地提高产奶量。
