Faecal excretion of Salmonella hadar from calves grazed on pastures fertilised with S. hadar-contaminated broiler litter

The risk of Salmonella hadar infection in weaned calves grazed on pasture artificially contaminated with the organism via broiler litter applied at commercial dressing rates was assessed. A group of four calves was grazed on artificially contaminated pasture and a control group was grazed on an adjacent identical paddock. A ninth calf was given S. hadar together with an anthelmintic drench, and a tenth was fed on a mixture of contaminated broiler litter and hay for 36 hours. Rectal swabs were collected from the calves at weekly intervals and examined for the presence of salmonellae. Two of the calves in the group on contaminated pasture and both the control positive calves shed S. hadar in their faeces on at least one occasion. The S. hadar contamination was detectable on the pasture for at least 42 days after application of the contaminated litter.