Albendazole residues in goat's milk: Interferences in microbial inhibitor tests used to detect antibiotics in milk

• Published in: Yàowu shi͡p︡in fenxi 2017-04, Vol.25 (2), p.302-305
• Main Authors: Romero, Tamara, Althaus, Rafael, Moya, Vicente Javier, Beltrán, María del Carmen, Reybroeck, Wim, Molina, María Pilar
• Format: Article
• Language: English
• Subjects: Albendazole; albendazole residues; Animals; Anti-Bacterial Agents; Antibiotics; Antiparasitic agents; Drug dosages; Drug Residues; Goat's milk; Goats; High performance liquid chromatography; Inhibitors; Liquid chromatography; Metabolites; Microorganisms; Milk; Original; Residues; screening tests; Sheep
• ISSN: 1021-9498; 2224-6614
• DOI: 10.1016/j.jfda.2016.08.007

Albendazole (ABZ) residues in goat's milk and their effect on the response of microbial inhibitor tests used for screening antibiotics were evaluated. A total of 18 Murciano-Granadina goats were treated with ABZ and individually milked once a day over a 7-day period. ABZ quantification was performed by high performance liquid chromatography. The ABZ parent drug was not detected. The maximum concentration of its metabolites (ABZ sulfoxide, ABZ sulfone, and ABZ 2-aminosulfone) was reached on the 1st day post treatment (260.0 ± 70.1 μg/kg, 112.8 ± 28.7 μg/kg, 152.0 ± 23.6 μg/kg, respectively), decreasing to lower than the maximum residue limit (MRL, 100 μg/kg) on the 3rd day post treatment. Milk samples were also analyzed by microbial tests [Brilliant Black Reduction Test (BRT) MRL, Delvotest SP-NT MCS and Eclipse 100], and only one positive result was found for Delvotest SP-NT MCS and Eclipse 100. However, a high occurrence of positive outcomes was obtained for BRT MRL during 6 days post treatment, whereas ABZ residues were not detected from the 4th day post administration, suggesting that factors other than the antiparasitic agent might affect the microbial test response. [Display omitted]