First evidence of Johne's disease in farmed red deer (Cervus elaphus) in Belgium

In a deer farm, chronic diarrhoea was seen in a 4-year-old hind. This anima l died in poor condition on the farm and Johne's disease was suspected. Zie hl-Neelsen staining of the faeces of this hind were positive for the presen ce of clumps of small acid-fast bacilli, but faecal cultures remained negat ive. Direct and indirect tests were performed on 24 hinds and stags (yearli ngs, 2- and 4-year-old animals). The indirect tests performed were serology (Mycobacterium paratuberculosis antibody ELISA, HerdChek(TM), Idexx), comp arative cervical skin test (CCT) and lymphoproliferation test (LT) using My cobacterium bovis purified protein derivative (PPD) and Mycobacterium avium PPD as antigens. Three positive serological results, three positive CCT an d eight positive LT were observed in hinds and stags older than 2 years. No positive serological results were observed in the yearling group, whereas some sensitisation was observed in the CCT as well as in the LT for the sam e group of animals. The degree of concordance between these indirect tests was poor. The three seropositive animals were slaughtered and subjected to post-mortem examination. Histopathology was performed on mesenteric lymph n odes and on the terminal ileum. Visual changes in some mesenteric lymph nod es were observed, no gross lesion was seen in the intestine. Although Ziehl -Neelsen staining yielded no positive results, a catarrhal focal necrotic e nteritis associated with a granulomatous lymphadenitis compatible with John e's disease was evidenced. The mycobacterial cultures on organ samples from slaughtered animals were positive after 2 months for M. avium subspecies p aratuberculosis and negative for M. bovis and M. avium. This is the first d escription of Johne's disease in a deer farm in Belgium. (C) 2000 Elsevier Science B.V. All rights reserved.