Analysis of the use of antibiotics in modern laying hen farms in the Dakar region and surrounding area

Abstract

have shown sometimes worrying prevalences. This prompted us to carry out this study, which aims to assess antibiotic use practices in laying hen farms where the withdrawal period is often not respected. Surveys were carried out in 70 farms, 59 of which were in the Dakar region and 11 in the Thiès region. A cross-sectional survey made it possible to determine the typology of farms according to the level of hygiene and it appeared that 50% of the farms had a good level of hygiene (class 3), 24.29% an acceptable level of hygiene (class 2) and 25.71% a poor level of hygiene (class 1). The surveys also showed that supervised farms had a better level of hygiene than unsupervised farms. This level of hygiene was closely related to the occurrence of diseases and the use of antimicrobials. Among the antibiotics, Quinolones are the most used (51%), followed by the Tetracycline family (16%) in the treatment of laying hens where self-medication is practiced in 50% and the dosage was strictly respected in only 27% of the farms. A follow-up of 15 of the 70 farms surveyed was carried out to check whether the behaviour of the farmers observed during the survey persisted. This follow-up showed results similar to those obtained during the cross-sectional survey. None of the farms respected the withdrawal periods for antibiotics used during production. These results show: failures of antibiotic therapy, the risk of the appearance of antibiotic resistance, as well as the risk of antibiotic residues in eggs. We recommend the implementation of antibiotic residue monitoring in poultry farming and the sensitisation of poultry farmers to the risk of antibiotic residues in consumed eggs.