Investigation And Research Of DHI Aplicatione In Dairy Farms Of Ningxia Area

Fifteen dairy farms were selected as the study subjects according to the scale and feeding management in Ningxia area.Some indexes and effected factors were analysed such as the milk yield,milk fat percentage,milk protein percentage,SCC(somatic cell count)by the GLM statistical model with the DHI data whose irregular and missing ones were removed from 2013 to 2016.In order to raise the production and control status of dairy cattle group,optimize the allocation of resources and improve the efficiency of production.The results of the study are as following:Dairy cows produce a lot of milk.The average daily milk yield of the 15 dairy farms studied was 32.43 kg,the average daily output of milk from 15 kg to 35 kg was gradually increased.With the year change,the average daily milk production increased gradually.In 2016,the average dairy milk were 35.59 kg of the 15 dairy farms,which were higher than the national average of 28.1kg of the average amount of milk production in the region in 2016.The quality of milk has improved markedly.The rate of milk fat and milk protein were significantly affected by the parity and calving season.There were 14.81% of the cows in 15 dairy farms,which had an average milk fat rate of less than 3%.Meanwhile,there were 5.26% of the cows in 15 dairy farms,which had an average milk protein rate of less than 2.6%.The highest rate of milk fat in winter was 3.878%,and the lowest milk fat rate in spring was 3.842%.Staring from the second parity,the rate of milk fat decreased with the increase of he number of parities.In winter,the milk protein rate was 3.25%,and the remaining three seasons were 3.24%.With the increase of the number,the milk protein rate basically decreasing from the second parity.The number of milk somatic cells was determined by year,calving season and parity.There are 13.81% cattle's somatic cells below 200000/ml in the 15 dairy farms.In 2016,the average somatic cells were 271800/ml,which were under the 296000/ml throughout the country.The calving season has the lowest number of somatic cells in spring,and the highest in autumn.With the increase of the number of parities,the number of somatic cells increases gradually.