Submitted to: Federation of Animal Science Societies
Publication Type: Abstract Only
Publication Acceptance Date: 3/18/2004
Publication Date: 7/25/2004
Citation: Johannsen, S.A., Hensley, M.J., Rasmussen, M.A., Griffith, R., Scanes, C.G. 2004. Diurnal variations and quantitative determination of the generation of carboxylic acids by microbial fermentation in the crop of the domestic turkey [abstract]. 2004 Joint Annual Meeting of the American Dairy Science Association, American Society of Animal Science, Poultry Science Association. p. 264.
Technical Abstract: The roles of avian crop include storage of ingesta but it may allow fermentation. It has been shown recently in the chicken that carcass contamination can be attributed to bacterial colonization of the crop tissue when the organ ruptures during evisceration. The present studies examine intra-luminal fermentation in the crop of young turkey poults. The following carboxlic acids were detected in the crop contents: formic, acetic, butyric, lactic, valeric, caproic, oxalic, phenyl acetic, succinic and fumaric acids. Unexpectedly, propionic, isobutyric and isovaleric acids were not detectable. At the beginning of the scotophase, there were considerable ingesta in the crop of turkey poults. During the scotophase, there were changes in the amount and characteristics (pH and carboxylic acid concentrations) of the crop contents. A progressive reduction in the contents was observed. Increases in the numbers of lactobacilli during the period of subjective night were observed. The pH of the contents decreased; for example declining from 5.9 one hour after the onset of the scotophase to 5.0 nine hours after the onset of the scotophase in control turkey poults. During the scotophase, there were linear increases the concentration of lactic, valeric and caproic acids (approximately 7 fold increases over 8 hours). There were decreases in the crop concentrations of formic, oxalic and succinic acids during the scotophase. Chronic addition of lactose or Lactobacillus sp. to the diet exerted modest effects on the carboxylic acid concentration in the crop contents. These data indicate the importance of microbial fermentation in the crop of poults and provide evidence of diurnal variation. These factors may have an impact upon metabolism and nutrition of the turkey and poultry in general.