Nutrition diet of grazing sheep and forage supply on natural grassland

摘要

Forages are a major asset of any livestock operation and the foundation of most rations in a forage-based livestock system. The available nutrients in a forage influence individual animal production (e.g. gain per animal); while the amount of forage produced affects production per hectare. The relationship between voluntary food intake and animal productivity is well recognized. Many studies related to the regulation of food consumption by sheep and cattle have been reported (Provenza 1996). Willoughby (1958) discussed a number of factors which might influence the herbage intake of grazing animals. By contrast, less attention has been given to the nutritional supply which influences the intake of herbage by grazing animals. It is necessary to know about animal daily nutrient requirements for production and forage supply in order to evaluate grazing capacity.