内蒙古典型草原施硫肥对绵羊氮硫代谢和生产性能的影响

INFLUENCE OF S FERTILIZER APPLICATION ON INNER MONGOLIA GRASSLAND ON NITROGEN AND SULPHUR METABOLISM AND PERFORMANCE OF GRAZING SHEEP

选择12只3岁半体重56kg 左右健康的内蒙古细毛羊(羯羊) ,于1995年6月16日～1995年10月5日分别放牧于3种施S肥处理(0 ,30和60kgS/hm2 的CaSO4 2H2O)的1hm2 天然草场上。实验结果表明 ,施S肥能使牧草中含S量从0.14 %提高到0.22 % ,N/S比从12.29 :1降到7.27 :1和7.86 :1 ;对绵羊干物质采食量没有明显影响 ,但提高了干物质的表观消化率 ;同时提高了N的表观消化率 ;施S肥明显增加了S的采食量和尿S的排出量 ;S的表观消化率明显提高 ,但吸收的S转化为畜产品效率有所降低 ;另外 ,施S肥对绵羊的日增重影响不大 ,但降低了畜体中N、S存留量的比(从14.21 :1降到10.22～10.80 :1)

Three 1 hm2 fenced paddocks were used in the experiment and S fertilizer was applied at 0,30 and 60kg CaSO42H2O/hm2.The grazing experiment was conducted with 1.5 year-old and about 56kg Inner Mongolia fine wool sheep(wethers).The stocking rates were 4 sheep/hm2 and the grazing period was 113 days from June 16 to Oct.5,1995.The results showed that S fertilizer application could increase S concentration in grasses from 0.14% to 0.22% and decrease N:S ratio from 12.29:1 to 7.27～7.86:1.The S fertilizer application did not affect DM intake and average daily gain,but increased S intake,urinary S output,apparent digestibility of deitary DM and N and S,and decreased the N:S ratio in retention products from 14.21:1 to 10.22:1～10.80:1.