title: Elimination of erythromycin in milk after intramammary administration in cows with specific mastitis: relation to dose, milking frequency and udder health.
abstract: Elimination of erythromycin in milk following intramammary therapy of specific mastitis in cows was studied. Five cows received therapy in one quarter (G1), and eight in two quarters with five milked twice (G2) and three thrice a day (G3). Dose infused was 300 mg/quarter 12 h × 5 times. The drug concentrations in milk were determined using microbial assay technique with Micrococcus luteus as the test organism. Considerable variations occurred in the excretion of drug; levels for treated quarters being 8.25 to 37.61 μg/ml at first milking that declined rapidly at 24 h and no drug activity was observed beyond 36 h post treatment. In total, about 6-25% of the last infused dose appeared in the milk. Drug crossed to 1/15 quarter (G1), 6/10 quarters (G2) and all the six untreated quarters (G3). Crossover levels were significantly higher in mastitic quarters and for G3 cows, but duration of excretion remained same in all cases. It seems that crossover of erythromycin to untreated quarters is related to the udder health and dose infused.
authors.affiliation: Department of Clinical Veterinary Medicine, Ethics and Jurisprudence, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, 141 004 Punjab, India. baljinderbansal@rediffmail.com
authors.forename: Baljinder Kumar
authors.initials: BK
authors.lastname: Bansal
authors.forename: Navdeep S
authors.initials: NS
authors.lastname: Bajwa
authors.forename: S S
authors.initials: SS
authors.lastname: Randhawa
authors.forename: Rakesh
authors.initials: R
authors.lastname: Ranjan
authors.forename: P S
authors.initials: PS
authors.lastname: Dhaliwal
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000032:analysis / Q000493:pharmacokinetics / Q000627:therapeutic use; D002417:Cattle; D004350:Drug Residues; D004917:Erythromycin / Q000008:administration & dosage / Q000032:analysis / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D005260:Female; D008321:Mammary Glands, Animal / Q000473:pathology*; D008414:Mastitis, Bovine / Q000188:drug therapy*; D008892:Milk / Q000737:chemistry*; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D004917:Erythromycin