Incidence and prevalence of microbial indicators and pathogens in ovine faeces in New Zealand

Abstract

The incidence and prevalence of micro-organisms in ovine faeces as potential sources of diffuse pollution to natural waters were determined. Faecal samples from lambs at slaughter (N=105) and sheep at pasture (N=220) were collected. E. coli, enterococci and Campylobacter spp. were enumerated in lambs (6.04×108, 1.44×107 and 3.3×10 5 g-1 respectively) and sheep (1.62×107, 6.8×105 and 2.08×103 g-1 respectively). Campylobacter spp., Salmonella spp. and Shiga toxin producing E. coli (STEC) were present in 80.9%, 1.9% and 3.8% oflamb samples, and 30.4%, 0% and 0.9% ofsheep samples respectively. Cryptosporidium spp. and Giardia spp. were present in 28.6% and 37.1% ofthe lamb faecal samples, and 3.6% ofsheep samples were positive for Cryptosporidium spp. The results ofthis study will be incorporated into models for estimating the potential impact of ovine faeces on natural waters. © 2011 The Royal Society of New Zealand.