Study On Change Of Grassland Community Of The Stipa Capillata+herbage And Lambs Eating And Growing In Warm Season

Taking Stipa capillata+herbage meadow steppe community in Zhaosu Basin as research object, feed intake and diet selection of Kazak rams were determined throught field observation and laboratory analysis. The growing rhythm, species richness and nutritive value of community were determined, too. This research will provide experimental support for herbivore and plants of reciprocity theory, the stability theory of ecosystem. It would offered decision basis for rational grazing management.The main results are as follows:(1) The nutritive value of Stipa capillata +herbage meadow steppe community is the highest between vegetative growth to initial bloom phases (end of may). In this period, the CP content of community reaches 17.95%. The content of NDF, ADF and Lignin are lower, they are 31.70%, 22.59% and 7.94%, respectively. Lignified degree of forage gradually improved with the passage of time, but CP content of forage gradually decreased.(2) Under continuous grazing, Stipa capillata, Achillea millefolium, Medicago falcate and Astragalus sp. which are good at palatability are the main dietary of Kazak rams.(3) The daily feed intake of Kazak rams has significant change in experiment period. Dry matter intake gradually improves with the grazing time increases. The rams'feces amount is different with different month everyday. The rams'feces amount gradually improves with different month.(4) The changes of Kazak weight have close relation with the seasonal changes in forage. The growth of grazing rams showed volatility with forage and seasonal changes.(5) Under feeding regime that grazing in daytime and abrosia in night, Kazak rams could make full use of daytime to ensure enough ingestion. Its activity rhythm and grazing behavior is: In the case of grazing for 690 min, feeding time is 481.05±29.03 min, occupide 69.72% of grazing time, average speed of intake is 55.03±8.97 M/min; ruminating time is 498.24±31.69min, occupide 35.69% of grazing time. Duraition of ruminant cycle is longers than others rams.ruminating time in night occupide 77.59% of ruminating time all-day. The time, frequency and speed of masticatory for every alimentary bolus were 46.82±2.51s, 74.56±3.65 T and 1.59±0.05 T/s, respectively.