Mycobacterium caprae infection in cattle and pigs on one family farm in Croatia: a case report

An outbreak of tuberculosis among bovines and pigs caused by Mycobacterium caprae is described in this paper. After tuberculin skin tests with bovine purified protein derivates (PPD) six cattle and one sow, own by a small family farm, tested positive whilst three pigs were suspected in 2004. All animals were euthanised and checked for gross pathological lesions. Generalised lesions were found in five cattle and two sows; however one calf and two gilts had lesions that were localised in the submandibular lymph nodes. Mycobacteria were isolated from tissue samples of six cattle and four pigs. Mycobacterial isolates were identified using classical biochemical tests and molecular methods (PCR, GenoType MTBC) as M. caprae. Mycobacterial Interspersed Repetitive Unit (MIRU) typing of isolated mycobacteria showed an identical number of repeats in 12 different loci. Results of the research confirmed the domination of M. caprae among infected cattle in Croatia; however this paper was the first to confirm a case of M. caprae in pigs. The source of the infection was not found.