Seasonal Changes Of Trace Elements And Analysis Of Their Sufficiency Or Lack In The Soil-Forage-Animal Ecosystem In Stud Farm Around Qinghai Lake

The contents of six trace elements (Cu Mn Fe Zn Mo Se) and their seasonal changes were studied in the view of trace elemental nutrition,came from water soil edible grass (gained by fistula set on esophagas) wool and other organs of sheep in stud farm of Sanjiaocheng of Qinghai province,such as plasma liver skeleton,etc.The results are as follows: (1 )The contents of the six trace elements arevery with season.At the beginning of the experiment,five health-aged sheep were chosen to operate on collecting -grass sample to calculate the sheep intake in grazing conditions.From the genenal level,the soil is in critical lack of Cu abundance of Fe serious lack of Se and Mo is lower than normal soil level.(2)In edible grass,contents of Cu Mn Fe Zn Mo are all higher in summer than in autumn and than in winter ,except for Se,in which contents of Fe Mn are higher and Zn Mo are in critical lack condition in three seasons,but it lacks Cu in winter and lacks Se in summer specially.(3)Contents of six trace elements in sheep hair changed with season,too,in which content of Fe is the same as in soil and in edible grass.Cu Mn Zn Mo are all lower than normal level,Se is enough in hot seasons while lack seriously in cold seasons,which is significantly lower than value of lack,0.079mg/kg,(p<0.01).(4)The level of trace elements in sheep is nearing lack of Cu plenty of Fe and serious lack of Se in the pasture from the results of plasma and organs of three seasons,such as liver heart lung etc.The study of abundant or lack condition of six trace elemens in sheep and their dyminics changes in different seasons will provide scientific basis to formulate measure of forage completatiom select and make up corresponding additive of trace elements.lt has significant meaning to take good advantage of superior natural conditions,increase local economic returns and improve ecological environment.