Aetiological Survey And Immunotherapy Of Mastitis Of Diary Cattle In North Xinjiang

In the study, we sample positive milk from the cattle with mastitis of various breeds at 7 ranches in north reclamation area of Xinjiang, based on the test results by clinical observation and reagent diagnosis. After increment and elective culture in laboratory, the pathogens inducing to mastitis are primarily separated and further identified through drug sensitivity tests in vitro and biochemical tests. We design primers by the use of PCR techniques to identify the dominant pathogen firstly, then culture the pathogen to make inactivated bacterin, and inoculate them to 3 sheep and 2 cattle according to immune program to prepare the high active antiserum through centrifugation. Finally, we choose 2 cattle with clinic-mastitis (average pH-value of their milk is about 7.3, somatic cells amount to 5,000,000 per ml. approximately and the cattle catch a slight inflammatory edema) and 3 cattle with sub-clinic mastitis (average pH-value of their milk is about 7.1, somatic cells count between 2,500,000 and 3,000,000 million per ml.) from the head of sick cattle which are infected by the dominant pathogen, then inject antiserum to them with different dose and different times.The result shows as follow:a. clinic mastitis's average detectable rate is 16.7% and sub-clinic rate is 36.3%.there are 219 cattle with sub-clinic mastitis in the random samples of 604 lactating cattle.b. we test pH-value, the quantity of somatic cells and alcohol positive milk and find that, there is no direct correlation between pH-value and alcohol positive milk; pH-value is a more important factor to examine mastitis and there is positive correlation between pH-value and the incidence and the magnitude of mastitis.c. we separate staphylococcus aureus, Streptococcus dysgalactiae, Salmonella, Escherichia coli, Pseudomonas sp and Prototheca. Staphylococcus aureus is the dominant pathogen causing mastitis based on the identification by PCR. We establish a new quick diagnosis technology of mastitis by the use of PCR techniques.d. to treat cattle by equally mixing the cattle's mixed antiserum (titer is 1:32) and the sheep's mixed antiserum (titer is 1:64), the pH-value and the quantity of somatic cells of the cattle with sub-clinic mastitis decline from 7.1 to 6.6 and from 2,000,000 to 500,000 per ml after 7 days, but the cattle with clinic mastitis decline from 7.3 to 6.7 and from 5,000,000 to 700,000 per ml after 10 days.