Specific IgY Used To Treatment Of Xinjiang Dairy Cow Mastitis

Dairy cow mastitis, as the key factor of limiting the development of dairy cow industry, cause big lose to the dairy farmers. At present, the main treatment used by dairy farmers to cow mastitis is using big volum of antibiotics. By doing this, however, leads cure effects weakened, cure period extended. Therefore, seeking for an effective, safety substitution of antibiotics is becoming our common goal. IgY, with the advantage of safty, enviroment friendly, inexpensive, and no antibiotic resistance, are used in prevention and treatment of disease caused by bacteria infection and can be wide application and development as a substitution of antibiotics. There was report that IgY was applied to treat dairy cow mastitis. This paper report that the pathogens isolated from milk samples of dairy cow mastitis collected from Xinjiang production and contruction corps, was used to produce IgY to treat clinical and subclinical mastitis. The study content and results are as followings:Firstly,14 kinds of bacteria were isolated from 60 clinical mastitis milk samples. There were two kinds of pathogen,9 strains of S. agalactiae, of which detection rate is 20%, and 7 strains of S. aureus, of which detection rate is 15.56%. The results of drug sensitive experiment showed that S. agalactiae was mainly drug resistant to vancomycin and pencillin, and S. aureus was drug resistant to vancomycin, fosfomycin, clindamycin,and gentamicin. Extensive diseases happened to every tissues and organs of the rats injected with such two strains of bacteria, such as spleens swollen and necrotic kidneys swollen and necrotic, kidneys swollen and lighter coloured, and livers darkened.Secondly, specific IgY were preduced by hens immunized with formaldehyde killed S. aureus and S. agalactiae in Ion-standing immunization response (titer > 10000) for 10 weeks with highest titer of 32000 and 24000.82.5% high purity IgY was isolated by water dilution, salt precipitation and ulreafiltration. Specific IgY could bound with specificity of the two kinds of bacteria and make bacterial aggregation. Specific IgY with 10 mg/mL got better performance than specificity of other density.The specific IgY of strains of S. aureus and S. agalactiae could bound with other isolated four strain of S. aureus and four strain of S. agalactiae as well. Immunofluorescence indicated that specific IgY could bound with two kinds of bacteria.Finally, we took mastitis cows into two groups. For clinical mastitics group, after treatment of specific IgY, the milk somatic cell counts decreased to 400000 from 800000. Bacterial counts obviously decreased and cure rate is up to 12.5%. For recessive mastitis group,after treatment of specific IgY, the milk somatic cell counts decreased to 300000 from 500000. Bacterial counts obviously decreased and meantime content milk protein and lactose obviously increased. Content of LDH and AKP were lower than before. Cure rate is up to 37.5%.In conclusion, this study took use of pathogens isolated from dairy cow mastitis to produce specific IgY of S.aureus and S.agalactiae, and studied the vitro activity of these specific IgY and applied it into real treatment of mastitis. This provided more evidence to prove that specific IgY can be as a protential substitution of antibiotics to treat dairy cow mastitis.