Disposition of ceftizoxime in Staphylococcal mastitis in Indian crossbred cows

Disposition of ceftizoxime was studied in Indian crossbred cows following a single IV dosing in field conditions. Six healthy lactating and six mastitic crossbred cows were assigned to two groups (Group 1 and Group 2). A single IV administration of ceftizoxime at the dose rate of 20mg/kg was administered to cows in both groups. Peak concentrations were recorded at 5min, decreasing sharply until 1h with plasma concentrations of 46.38±0.30μg/mL; concentrations were below detection limits at 24h. Ceftizoxime achieved peak concentrations at 96h and persisted up to 120h at a concentration of 36.71±0.96μg/mL in the milk of mastitic Indian crossbred cows. Staphylococcal colony count in acute mastitis was 52.33±4.98×10⁵ colony forming units/mL milk and no growth was detected at 96h post-dosing, indicating that ceftizoxime following single IV administration at 20mg/kg may be effective to treat acute staphylococcal mastitis.