放牧绵羊行为生态学研究Ⅱ不同放牧率对放牧绵羊牧食行为的影响

Behavior Ecology of Grazing Sheep Ⅱ Influence of Stocking Rates on Foraging Behavior of Wether

于１９９３年６月８～９日，在中国科学院内蒙古草原生态系统定位研究站，以５岁阉割绵羊在不同放牧率下的牧食行为进行试验研究。试验结果表明，不同放牧率１．３３和２．６７羊／ｈｍ２（放牧１３８ｄ）对绵羊的牧食行为有明显地影响：（１）放牧率较低时，能明显缩短采食时间，提高采食速率、每步采食口数和每口采食量及日采食量；（２）明显延长反刍时间，增加反刍周期数和反刍总食团数，对其它牧食行为影响不大。结果表明，在春末夏初，放牧率１．３３羊／ｈｍ２比２．

Foraging behavior of wether (5-year-old)was investigated under differnet stocking rates 1.33 sheep/hm 2 and 2.67 sheep/hm 2 (138 days) by tracing observation started from June 8～9 1993 at the Inner Mongolia Ecological Research Station, Chinese Academy of Sciences. The results showed that stocking rates had a significant effects on foraging behavior of wether. The lower stocking rate (1.33 sheep/hm 2) was more suitable under the local experimental conditions. The ingestive time was decreased, and the biting rate, the number of bite per step, the biting mass and the daily intake were increased under this stocking rate. Compared to the higher stocking rate (2.67 sheep/hm 2) the time of rumination was longer and the number of ruminating circle and ruminating food bolus were increased when sheep was grazed at the lower stocking rate.