title: Drug residues in milk after intrauterine injection of oxytetracycline, lincomycin-spectinomycin, and povidone-iodine in cows with metritis.
abstract: A study was conducted to document the maximum retention times of antimicrobial residues in milk after their use in intrauterine treatment of metritis in lactating cows and to evaluate several risk factors hypothesized to influence the retention time of these drugs. Oxytetracycline (3 g), lincomycin-spectinomycin (2 g of one-third lincomycin and two-thirds spectinomycin), or povidone-iodine (6 g) were given to cows with metritis by intrauterine route. The Bacillus stearothermophilus var calidolactis disk assay was performed on each milk sample. Of the 61 cows treated with oxytetracycline, 30 had residues in their postinjection milk for variable periods (range, 12.5 to 44.0 hours; mean, 26.6 +/- 10.3). Of the 47 cows treated with lincomycin-spectinomycin, 17 had residues in their postinjection milk for various periods (range, 14.5 to 24 hours; mean, 19.5 +/- 8.9). Povidone-iodine was not detected in milk. Because a high number of cows (n = 61) were treated with oxytetracycline, only data from these cows were used in testing the influence of 3 factors (severity of metritis, time after parturition when cows with metritis were treated, and parity) on maximum retention of the drug in milk. Severity of metritis did not have a significant influence (P greater than or equal to 0.1) on the maximum retention time of the drug. The retention time decreased linearly with the increase of time after parturition when the cow with metritis was treated. First lactation cows had a significantly (P less than or equal to 0.01) shorter retention time than did older cows.
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000627:therapeutic use*; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy* / Q000378:metabolism; D004716:Endometritis / Q000188:drug therapy / Q000378:metabolism / Q000662:veterinary*; D005260:Female; D008034:Lincomycin / Q000032:analysis / Q000627:therapeutic use; D008892:Milk / Q000032:analysis*; D010118:Oxytetracycline / Q000032:analysis / Q000627:therapeutic use; D011205:Povidone / Q000031:analogs & derivatives*; D011206:Povidone-Iodine / Q000032:analysis / Q000627:therapeutic use*; D000198:Spectinomycin / Q000032:analysis / Q000627:therapeutic use
chemical_list: D000900:Anti-Bacterial Agents; D011206:Povidone-Iodine; D000198:Spectinomycin; D008034:Lincomycin; D011205:Povidone; D010118:Oxytetracycline