摘要
A study was undertaken to evaluate the macromineral nutritional status of the grazing sheep at the three farms in northern China. On each farm 140, 2 or 3 -year - old reproducing ewes were used. The results obtained showed that Potassium, Magnesium and Phosphorus in the pasture were all lowest in winter and early spring. However, the ewes were given some grain - based supplements. hay and silage during this period. Of these supplements, concentrates contained high levels of phosphorus, and both hay and silage contained high levels of potassium, so that, severe deficiency of these elements during winter or spring was not likely- The results also found that summer and autumn may be when sheep were at most rise of a macromineral deficiency. Although pasture was plentiful and both protein and digestible energy were higher than other seasons of the year, sodium, in both summer and autumn, and phosphorus in autumn, were below published requirements.So, supplementation of both the elements during summer and autumn seasons are so important to improving growth and wool production as well as reproduction of the grazing ewes.
A study was undertaken to evaluate the macromineral nutritional status of the grazing sheep at the three farms in northern China. On each farm 140, 2 or 3 -year - old reproducing ewes were used. The results obtained showed that Potassium, Magnesium and Phosphorus in the pasture were all lowest in winter and early spring. However, the ewes were given some grain - based supplements. hay and silage during this period. Of these supplements, concentrates contained high levels of phosphorus, and both hay and silage contained high levels of potassium, so that, severe deficiency of these elements during winter or spring was not likely- The results also found that summer and autumn may be when sheep were at most rise of a macromineral deficiency. Although pasture was plentiful and both protein and digestible energy were higher than other seasons of the year, sodium, in both summer and autumn, and phosphorus in autumn, were below published requirements.So, supplementation of both the elements during summer and autumn seasons are so important to improving growth and wool production as well as reproduction of the grazing ewes.
作者
D X Lu,(Inner Mongolia Academy of Science.Hohhot City,Inner Mongolia Autonomous Region,PRC)S X Yut,(Institute of Animal Science,Chinese Academy of Agricultural Science,Malianwa,Haidianqu,Beijing,PRC)R Z Yang,(Xinjiang Institute of Animal Science,Xinjiang Academy of Animal Science.Yiu Hou Rd,Urumqi,Xinjiang Uygur Autonomous Region,PRC)K Shao(Inner Mongolia Academy of Science.Hohhot City,Inner Mongolia Autonomous Region,PRC)D G Masters(CSIRO Division of Animal Production.Private Bag,P.O.Wembley,Western Australia 6014)
出处
《畜牧与饲料科学》
1997年第S1期195-201,共7页
Animal Husbandry and Feed Science