Reference

Persistence of antibiotics in milk from cows treated late in the dry period

Persistence of antibiotics in milk from cows treated late in the dry period. Johnson, M. E.; Martin, J. H.; Baker, R. J.; Parsons, J. G. (Dairy Sci. Dep., South Dakota State Univ., Brookings, S. Dak., USA). J. Dairy Sci., 60(10), 1655-61 (English) 1977. CODEN: JDSCAE. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacodynamics) Section cross-reference(s): 17 Nineteen cows were treated via intramammary infusion at various times prior to calving with one of two dry cow antibiotic prepns. (benzathine cloxacillin [23736-58-5] or procaine penicillin G [6130-64-9]). Milk samples from these cows after calving were analyzed for antibiotic residues by the Sarcina lutea cylinder plate method. Eight cows were treated with cloxacillin. Cloxacillin was detected in the milk of only 2 cows after calving and then for only one milking, so no problem should exist with cloxacillin if the manufacturer's recommendations are followed. Penicillin residues were not detected in milk samples taken from cows treated more than 9 days prior to calving with the dry cow penicillin prepn. However, 7 of 9 cows treated with penicillin up to 9 days prior to calving had detectable penicillin residues in the milk from treated quarters after calving. Only 1 cow had detectable penicillin residues longer than the manufacturer's recommended milk withholding time of 96 h, and this cow was treated only 3 days prior to parturition. Normal routine on a dairy farm and adherence to manufacturer's recommendations should result in no antibiotic residue problems in milk from cows treated during the dry period for mastitis control with either cloxacillin or penicillin.

Antibiotic treatments at drying-off of induced and natural infections of the bovine mammary gland

Antibiotic treatments at drying-off of induced and natural infections of the bovine mammary gland. Poutrel, B.; Ducelliez, M. (Cent. Rech. Tours, Inst. Natl. Rech. Agron., Nouzilly, Fr.). Ann. Rech. Vet., 8(3), 333-40 (English) 1977. CODEN: ARCVBP. ISSN: 0003-4193. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacodynamics) Two long acting antibiotic prepns., cloxacillin benzathin [23736-58-5] (0.5 g) and Combisec (penicillin G-dihydrostreptomycin) [8017-41-2] (1 million units: 1 g) in an oily base, assocd. with 3% Al monostearate, were used for the treatment at drying off of 32 cows (124 quarters) either infected spontaneously or induced. For the group of infections due to the major pathogens the therapeutic efficiency of the 2 prepns. was the same. Seventeen of 24 (71%) staphylococcal infections were cleared by cloxacillin against 23 of 27 (85%) for penicillin-streptomycin. The treatment failures of the 48 induced infections by Staphylococcus aureus could not be linked to the antibiotic sensitivity of the strains used nor to a previous treatment during the lactation. On the other hand the length of infection and the serotype of the strains had an influence on the clearance rate obtained. The rate of new infections obsd. after the cloxacillin treatment (8%) was not different from that obsd. when penicillin-streptomycin was used (13%). Of 13 new infections due to the major pathogens, 10 were infections due to Streptococcus uberis. Overall, the therapeutic and prophylactic efficacity of cloxacillin and penicillin-streptomycin is the same.