title: Detection limits of antimicrobials in ewe milk by delvotest photometric measurements.
abstract: The Delvotest method detection limits per manufacturer's instructions at a fixed reading time of 3 h for 24 antimicrobial agents were determined in ewe milk by photometric measurement. For each drug, eight concentrations were tested on 20 ewe milk samples from individual ewes. Detection limits, determined by means of logistic regression models, were (microg/kg): 3, amoxycillin; 2, ampicillin; 18, cloxacillin; 1, penicillin "G"; 34, cefadroxil; 430, cephalosporin "C"; 40, cephalexin; 20, cefoperazone; 33, Ceftiofur; 18, cefuroxime; 6100, streptomycin; 1200, gentamycin; 2600, neomycin; 830, erythromycin; 100, tylosin; 180, doxycycline; 320, oxytetracycline; 590, tetracycline; 88, sulfadiazine; 44, sulfamethoxazole; 140, sulfametoxypyridazine; 48, sulfaquinoxaline; 12,000, chloramphenicol; and 290, trimethoprim. Whereas the beta-lactam antibiotics, sulphonamides, and tylosin were detected by Delvotest method at levels equal to those of maximum residue limits, its sensitivity needs to be enhanced to detect aminoglycosides, tetracyclines, streptomycin, chloramphenicol, and trimethoprim residues in ewe milk or to develop an integrated residue detection system for ewe milk with different sensitive microorganisms for each group of antiinfectious agents.
authors.affiliation: Departamento de Ciencia Animal, Universidad Politécnica de Valencia, Camino de Vera, 14. Apartado 22012, (46071) Valencia, España.
authors.forename: R L
authors.initials: RL
authors.lastname: Althaus
authors.forename: A
authors.initials: A
authors.lastname: Torres
authors.forename: A
authors.initials: A
authors.lastname: Montero
authors.forename: S
authors.initials: S
authors.lastname: Balasch
authors.forename: M P
authors.initials: MP
authors.lastname: Molina
mesh_terms: D000617:Aminoglycosides; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D000890:Anti-Infective Agents / Q000032:analysis*; D002701:Chloramphenicol / Q000032:analysis; D004350:Drug Residues / Q000032:analysis; D005260:Female; D007769:Lactams; D016015:Logistic Models; D018942:Macrolides / Q000032:analysis; D008892:Milk / Q000737:chemistry*; D010783:Photometry / Q000379:methods*; D012680:Sensitivity and Specificity; D012756:Sheep; D013449:Sulfonamides / Q000032:analysis; D013754:Tetracyclines / Q000032:analysis; D014295:Trimethoprim / Q000032:analysis; D015645:Tylosin / Q000032:analysis
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D007769:Lactams; D018942:Macrolides; D013449:Sulfonamides; D013754:Tetracyclines; D002701:Chloramphenicol; D014295:Trimethoprim; D015645:Tylosin