Study On Traits Of Meat Sheep New Population In Karst Areas Of Southwest China

The hydrothermal conditions in karst areas of Southwest China are well.There are abundant grassland resources,which are good for developing grassland ecological animal husbandry.However,because there is lacking specialized meat sheep,the development of grassland animal husbandry in the areas is quite backward.Qinglong,Guizhou province is located in karst areas of Southwest China.It is a typical rural representative of Guizhou province and even the entire karst areas of the Southwest.In order to develop meat sheep with local advantages and solve the key problem of lacking meat sheep,Qinglong had introduced many different meat sheep.With Dorper sheep as male parent,Hu sheep and some other domestic meat sheep as a female parent for meat sheep production,a new group of sheep-meat sheep new population had gradually formed after years of natural selection and artificial selection.In this paper,we had researched on the germplasm characteristics of meat sheep new population in karst areas of the Southwest by using living measurement,tracking,masks,microsatellite marker,and some other research methods.It will have a guiding function for the rational utilization of germplasm resources and the development of grassland ecological animal husbandry.The main content of this research included the measurement of sheep’s weight and body sizes,the determination of blood biochemical index,the observation of grazing behavior and the measurement of feed intake and genetic polymorphism of microsatellite,etc.Through the research we found that:(1)The growth speed of meat sheep new population was fast,and the weight,body measurements were fine,and the blood biochemical index values were normal.It was worth to continue breeding to further improve.Among them,the average body weight and chest circumference of 6 months rams were 28.49 kg and 67.44 cm,and the yearling rams were 63.56 kg and 90.16 cm,and adult rams were 81.60 kg and 102.4cm.The average body weight and chest circumference of 6 months ewes were 26.90 kg and 68.62 cm,and the yearling ewes were 45.92 kg and 82.63 cm,and adult ewes were 64.01 kg and 93.02 cm.With different age and sex,the blood biochemical index values of sheep were different,which related to the nutritional status of sheep,the external environment and physiological condition.(2)The grazing behaviors of meat sheep new population and goats were different.The feeding time of meat sheep new population accounted for 52.5% of grazing time,which was significantly higher than that of goats(P<0.05).The standing time accounted for 23.1% of grazing time,which was significantly lower than that of goats(P<0.01).The difference of ruminating time and lying time between sheep and goats was not significant,and the average number of chewing each group while ruminating was almost the same.The grazing feed intake of each meat sheep new population was 2.64 kg/d,which was higher than that of goats,but not significant.Therefore,meat sheep new population had a strong adaptability to the special grassland ecological environment in karst areas of the Southwest,and they could well adapt to the local grazing environment.(3)Selecting four microsatellite loci(BM1329,OarHH55,OarAE101 and BM143)to analyze the genetic polymorphism of meat sheep new population,Dorper sheep,Hu sheep and Weining sheep.The four microsatellite loci in all sheep populations had showed high polymorphism,and 41 alleles had been detected.The average polymorphism information content and heterozygosity were 0.6950 ~ 0.8375 and 0.7527 ~ 0.8634 respectively.Among them,the average polymorphism information content and heterozygosity of meat sheep new population were 0.8128 and 0.8487 respectively,which meant that meat sheep new population had abundant genetic polymorphism.In the phylogenetic tree that constructed by UPGMA method,meat sheep new population clustered together with Hu sheep first,then with Weining sheep,and last with Dorper sheep.In conclusion,taking Dorper sheep as male parent and Hu sheep as female parent was an ideal choice to the production of meat sheep in karst areas of Southwest China.With the sequentially strengthening the breeding of meat sheep new population in karst areas of the Southwest,it was expected that meat sheep new population would develop into a good meat sheep breed(group).