Hay modulation in Bijie, Guizhou

Hay modulation is subject to many natural factors in South China Karst area which objectively impeded the development of herbivorous animal husbandry. In order to obtain some basic data for hay modulation and provide support for the development of animal husbandry in karst area, the present paper analyzes the feasibility of hay modulation by studying the drying process of 8 main cultivated forage and the moisture loss rule combining with the precipitation and temperature over several years. Eight species of grass were natural drying in field in Salaxi Demonstration, Bijie. The weight species of grass, temperature and humidity of air were recorded during drying and climate over the years in the region especially the minimum and maximum temperature variation in April, May, June, July of recent 3 years were also analyzed. The results showed that the hay rates of 4 species of gramineae herbage were higher than those of 3 species of legume forages and Cichorium intybus. Trifolium repens, T. pratense and C. intybus were not suitable for forage drying from the perspective of appearance evaluation. The effects on hay decreased in the following order: drying time ＞ air humidity ＞ air temperature. July was the most suitable time for hay modulation after comprehensively analyzing the climatic factors.