不同放牧率下绵羊的采食量与食性选择研究

在松嫩平原羊草草地，通过控制放牧实验对放牧绵羊的采食量和食性选择进行了研究。结果表明，放牧绵羊的时限采食量（4h）平均为0．27kg干物质，且随放牧率的减小而增大；绵羊对各种植物的选择性采食顺序可分为嗜食、喜食、可食和少食4个等级；随着放牧率不断增大，原为少食的雨草苔、长叶碱茅莨和箭头唐松草成为可食植物，原为可食的羊草、星星草和牛鞭草成为喜食植物，原为喜食的鸡儿肠和罗布麻成为嗜食植物，蔓委陵菜、五脉山黎豆、拂子茅和芦苇的选择性指数也有所提高；放牧绵羊的食物组成与各种植物在群落中的相对生物量和高度呈极显著的正相关，而与密度相关性不大。

The study on the intake and dietary composition of sheep under different stocking rates

The study on the intake and dietary composition of grazing sheep was conducted by controlled experiment in the Songnen grasslands.The results showed that:the mean daily intake of sheep was 0.27 kg(dry matter).The daily intake was increasing with decreasing of stocking rates.The order of preferred plant species can be divided into 4 classeds.The dietary composition of grazing sheep was changed because the herbage resource was different under different stocking rates.For example,Leymus chinensis,Pusccinellia tenuiflora and Hemarthria altissima were changed into preferred herbag.The selective ingestion of herbage had a positive correlation with herbage relative biomass and height ,but it had no obvious correlation with density.