自然和临时草地对羊奶产量的影响（英文）

Influence of Natural and Temporary Pasture on Milk Production of Sheep

保加利亚是一个具有温和大陆性气候的国家,饲养绵羊主要是为了获取羊奶,放牧期从四月到十月,冬季需配给干草和复合饲料进行喂养。为了比较自然放牧和临时的牧场放牧状态下,羊的产奶量的差异。在91d的试验放牧期,用类似的方法,将这30只黑面母羊物种分成每10只一组。冬季口粮期开始后的42d,第一组在天然牧场放牧,第二组每天喂苜蓿干草和复合饲料,第三组在临时牧场放牧。试验期最后的28d,与在天然牧场上放牧的羊和冬季在临时牧场上放牧相比较,发现在临时牧场上放牧的羊的产奶量增加了42.3%和26.2%。放牧期间,在天然的牧场上放羊,羊奶的脂肪含量比冬天饲料喂养和在临时牧场上放牧的这些羊高19%和23%。临时牧场干重年产量首次从1 497 kg·hm-2增长到6 480 kg·hm-2或者每周平均1 620kg·hm-2,然而天然牧场中从967.6kg·hm-2增加到2 668.8kg·hm-2。在营养生长期间,临时牧场豆科作物的比例从64.4%降低到43.4%,草类从32.3%增长到51.0%。然而在天然牧场中草类占的比例变化范围是从94%到77%,豆科作物所占比例从1.0%到13.5%.

Bulgaria is a country with moderate continental climate and sheep,bred primarily for milk are grazing from April to October,and in the winter they are feeding in stallon ration based on hay and compound feed.The purpose of the experiment was to compare milk production of sheep grazed on natural and temporary pasture.For this 30 ewes of Pleven Blackface breed were used divided into three groups of 10 animals each,by the method of analogues.The experimental grazing period of 91days（13weeks）,began after 42 days winter ration period.First group was to grazing on natural pasture,the second group remained in stallfed on ration based on alfalfa hayand compound feed,and the third group was to grazing on temporary pasture.The total milk of the group grazing throughout the grazing period on temporary pasture was respectively 42.3% and 26.2% higher than that of the first group of sheep grazing on natural pasture and those of a second group left in stall nutrition and last 28 days grazing on temporary pasture.The content of fat in the milk during the grazing period for sheep grazed on natural pasture was 19% and 23% more higher than the sheep fed on winter ration and these grazed on temporary pasture.The yield at first growth of temporary pasture increased from 1 497kg·hm-2 to6 480kg·hm-2 dry mass or an average of 1 620kg·hm-2 per week while in natural pasture increased from967.6kg·hm-2 to 2 668.8kg·hm-2 dry mass.During the first vegetation growth,the proportion of legume in temporary pasture decreased from 64.4%to 43.4%,while grass increased from 32.3%to 51.0%,while in the natural pasture the grass varied from 94%to 77% and legume increased from 1.0%to 13.5%.