Dietary enzyme and zinc bacitracin reduce colonisation of layer hens by the intestinal spirochaete Brachyspira intermedia
Hampson, D.J., Phillips, N.D. and Pluske, J.R. (2002) Dietary enzyme and zinc bacitracin reduce colonisation of layer hens by the intestinal spirochaete Brachyspira intermedia. Veterinary Microbiology, 86 (4). pp. 351-360.
*Subscription may be required
Brachyspira intermedia strain HB60 was used to experimentally infect 40 individually caged 22-week-old laying hens. Another 10 control birds were sham-inoculated with sterile broth. All chickens received an experimental layer diet based on wheat. The infected birds were randomly divided into four groups of 10, with the diet for each group containing either 50ppm zinc bacitracin (ZnB), 100ppm ZnB, 256ppm of dietary enzyme (Avizyme®, 1302), or no additive. Birds were kept for 6 weeks after infection, and faecal excretion of B. intermedia, faecal water content, egg numbers, egg weights and body weights were recorded weekly. Control birds remained uninfected throughout the experiment. B. intermedia was isolated significantly less frequently from the groups of experimentally infected birds receiving ZnB at 50ppm or enzyme than from those receiving 100ppm ZnB or no treatment. Infected birds had a transient increase in faecal water content in the week following challenge, but no other significant production differences were detected amongst the five groups of birds in subsequent weeks. It was not established how the ZnB at 50ppm and the dietary enzyme reduced the ability of the spirochaete to colonise, but it may have been by bringing about changes in the intestinal microflora and/or the intestinal microenvironment.
|Publication Type:||Journal Article|
|Murdoch Affiliation:||School of Veterinary and Biomedical Sciences|
|Copyright:||© 2002 Elsevier Science B.V|
|Item Control Page|