Small ruminants as carriers of the emerging foodborne pathogen Arcobacter on small and medium farms

In the past, the emerging pathogen Arcobacter has been associated with reproduction disorders and mastitis in livestock, but has also been isolated from healthy animals. Information on Arcobacter excretion by small ruminants is scarce. For this reason, the study reported in this paper aimed to assess the occurrence of arcobacters in healthy sheep and goats on farms. In total, 330 faecal samples were collected on three sheep, four goat farms, and one mixed farm. Drinking water, milk and urine samples were also collected on the same farms. Isolates, obtained by an Arcobacter selective method, were identified with a species-specific multiplex-PCR and characterized by enterobacterial intergenic consensus PCR. It was found that arcobacters were excreted in 43.1% of the faecal samples from sheep and out of 10.7% of those from goats. The percentages varied between the farms, animals and the sampling occasions. In both goats and sheep, Arcobacter butzleri and Arcobacter cryaerophilus were the dominant species, and the majority of the strains were only excreted once. This study indicates that healthy sheep and goats, in particular the former, are important carriers of Arcobacter species. The fact that arcobacters are asymptomatically present in the intestinal tract of healthy small ruminants poses an important risk for faecal contamination of carcasses during slaughter and possibly of milk on farms.