Efficacy of selected antimicrobial agents in treating diarrheal disease in neonatal lambs
Gates, N.L.; Rich, J.E.; Myers, L.L.; Harp, J.A.
Veterinary Medicine-Small Animal Clinician 74(5): 707-709
1979
ISSN/ISBN: 0042-4889 PMID: 157584 Document Number: 142398
Groups of 25 lambs (1-2 days old) with diarrhoea were given either a placebo, or spectinomycin (4.6 mg/kg by mouth), or sulfadimethoxine (11.4 mg/kg by mouth), repeated 24 hours later. Responses were scored poor (diarrhoea present 24 hours after second dose), good (diarrhoea ceased 24 hours after second dose) or excellent (diarrhoea ceased 24 hours after first dose). Responses to spectinomycin were good 20% and excellent 80%; to sulfadimethoxine good 48% and excellent 52%; and to placebo poor 36%, good 16% and excellent 48%. Cultures of fecal swabs produced 128 isolates of Escherichia coli, 3 of Salmonella arizonae and one of S. oranienburg. In a lamb ligated gut loop test for enteropathogenicity all of the E. coli isolates were negative, S. arizonae isolates were negative in 4 of 5 lambs but the S. oranienburg isolate was strongly positive. Antibiotic sensitivity tests showed that 2 enteropathic E. coli isolates from another flock and the two Salmonella spp were sensitive to spectinomycin. The results indicate that spectinomycin is effective against several enteropathic bacteria in lambs.