Lincomycin toxicity in farm rabbits: report on a severe case

Abstract

[EN] In this study, we describe a case of severe toxicity by lincomycin contamination in feed on a farm housing 1800 rabbit does. The farm used a two-batch system, with parities 24 and 3 d ago, respectively. The rabbits that had consumed the feed developed anorexia 24-48 h later, followed by enteritis-diarrhoea and death. Mortality was >70% in does, >50% in 28-day-old kits. None of the 7-day-old kits died from this cause. A total of 125 non-lactating does that had consumed another type of feed from the same supplier were not affected; 10 of them were given the contaminated feed and the same problem occurred. Treatment based on presumptive diagnosis was unsuccessful. Microbiological and histopathological studies identified Clostridium spiroforme, which predominated over coliform bacteria. Toxicology studies requested by the producers verified the existence of 1.6 ppm amoxicillin in the first place; weeks later, further analyses determined 410 ppm lincomycin in doe feed. It also contained the prescribed quantity of 199 ppm tilmicosin. We recommended the stamping-out on the farm.