Abstract: In the experiment,10⁴ CFU/mL/3 to 4 kg (body weight) of Staphylococcus aureus that was isolated from the milk of dairy cattle with mastitis were infused into the third of mammary gland in 32 healthy rabbits,then the clinical mastitis model were challenged. 32 rabbits were randomly divided into A (IFN-γ),B (Ciprofloxacin),C (IFN-γ and Ciprofloxacin Lactate),D (normal saline) as four treatment groups,each contains 8 rabbits,then delivery drug only after 6,18 h as first dosage. Each group,respectively,from before established model 1, 4,12,24,36,48,72 h observe their temperature,heart rate and respiratory rate and other clinical indicators,and collect blood 0.5 mL,serum 1 mL,for blood and blood biochemical detection,and determination of inflammatory cytokines (ELISA),to study its therapeutic effect. The results showed that: ① 12 to 48 h after challenged,A,B group,the total number of peripheral white blood cells was significantly higher than the C groups (P<0.01),and was higher than the C group (P<0.05) when the 72 h after challenged,but inter-group no significant difference (P>0.05); 12 to 72 h after challenged,D group was significantly higher than the A,B,C group (P<0.01). Results showed that γ-interferon and the combination of ciprofloxacin in the body increased neutrophil phagocytic leukocytes and bactericidal power is superior to other groups. ②12 to 48 h after challenged,A,B serum calcium content was significantly lower than the C group (P<0.01),and was lower than the C group (P<0.05) when the 72 h after challenged,However,inter-group difference was not significant (P>0.05); 12 to 72 h after challenged,D group was significantly lower than the A,B,C group(P<0.01). Showed that the γ-interferon and the combination of ciprofloxacin lactate than alone are more effective in slowing decline in the level of calcium ion concentration,reducing capillary permeability and reduce inflammatory exudation. ③C group of TNF-α and IL-6 concentration was lower than A,B group (P<0.05) when the 12 to 24 h and 72 h after challenged,and was significantly lower than A,B group (P<0.01),A,B groups were not significantly different (P>0.05); the other three groups was significantly lower than the D group (P<0.01) when the 12 to 72 h after challenged. The results demonstrated that γ-interferon with ciprofloxacin in the treatment of clinical Staphylococcus aureus mastitis with a certain degree of synergy.

Key words: Staphylococcus aureus; clinical mastitis; animal model; recombinant γ-interferon; treatment