Evaluation of tetracycline and beta-lactam residues in cow milk produced in Central Benin

Abstract

The objective of this study was to evaluate the presence of tetracycline and beta-lactam residues with the Twinsensor kit (KIT 020) in the raw milk of cows raised in sedentary cattle farms located in eight communes of Zou Department and one commune of Collines Department in Central Benin. A total of 261 samples of raw bulk milk were collected at the rate of three samples per farm taken two days apart. The proportions of tetracycline- and beta-lactam-residue positive milk samples per commune ranged from 1.4% to 100% and 22.2% to 100%, respectively. All samples in Zakpota were positive for tetracyclines, whereas in the other eight communes less than 50% of the samples were positive for this family of antibiotics. The highest proportions of milk (100%) positive for beta-lactam residues were observed in Abomey, Agbangnizoun, Dassa-Zoumè, Djidja and Zakpota. Since the detection limits for tetracyclines and beta-lactam antibiotics by the qualitative method used were below the maximum residue limits recommended by the European Union, positive samples should be confirmed by a physicochemical test. Nevertheless, health monitoring and treatment of animals in the study area could be improved to preserve the health of milk consumers.