Experiments with three new intramammary antibiotic combination products for the treatment of subclinical mastitis in lactating cows
Storper, M.; Bar Moshe, B.; Ziv, G.; Saran, A.
Refuah Veterinarith 38(4): 154-166
The efficacy of 3 new intramammary antibiotic combination products in eliminating streptococci and staphylococci from subclinically infected udders of lactating cows, and the duration of antibiotic residues in milk were determined. Products tested were Amclox (75 mg ampicillin sodium and 200 mg cloxacillin sodium), Kanapen (250 mg kanamycin sulphate and 300 000 units procaine penicillin G), and Ampicet (100 mg ampicillin sodium and 200 mg cephalothine sodium). Each product was infused twice, with a 24 h interval, into the quarters of the udder. The efficacy of each of the products in eliminating streptococcal infections was rather high and compared favourably with the reported efficacy of products containing only penicillin G, only cloxacillin, and a combination of ampicillin and cloxacillin. With Amclox, the average cure rate of Staphylococcus aureus infection was 47.5 %, ranging between 12.1 and 87.8 % in 3 herds. Kanapen eliminated 79.2 and 88.6 % of S. aureus cow infections in 2 herds. Ampicet cured 66.0% of S. aureus cow infections in 5 herds although in one herd only 15.6% of the infections were eliminated. Antibiotic activity was found in milk up to 84 h after Amclox therapy, whereas the required milk withholding periods were 108 h and 48 h after treatment with Kanapen and Ampicet, respectively, (all in herds milking 3 times daily).