QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 139/9/1714    most recent jn.109.108506v1 Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Google Scholar Articles by Penner, G. B. Articles by Oba, M. PubMed PubMed Citation Articles by Penner, G. B. Articles by Oba, M.

---

Nutrition and Disease

Epithelial Capacity for Apical Uptake of Short Chain Fatty Acids Is a Key Determinant for Intraruminal pH and the Susceptibility to Subacute Ruminal Acidosis in Sheep^1,2

³ Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada and ⁴ Institute for Veterinary Physiology, University of Leipzig, 04103 Leipzig, Germany

Subacute ruminal acidosis (SARA) is a common digestive disorder occurring in ruminants, with considerable variation in the severity of SARA observed among animals fed the same diet. Our aim in this study was to determine whether differences in the capacity of the ruminal epithelium for the apical uptake of acetate and butyrate (determined in Ussing chambers after slaughter) explains differences observed for the severity of a preceding episode of SARA in vivo. Adult sheep with an indwelling small ruminant ruminal pH measurement system (SRS) were randomly assigned to either a SARA induction treatment (oral drench containing 5 g glucose/kg body weight; n = 17) or a sham treatment (SHAM; n = 7; 12 mL water/kg body weight). Sheep receiving the glucose drench were further classified as nonresponders (NR; n = 7) or responders (RES; n = 7) according to their ruminal pH profile for the 3 h following the oral drench. Mean ruminal pH for the 3 h following the drench differed among groups (P < 0.001), with it being highest for SHAM (6.67 ± 0.08), intermediate for NR (5.97 ± 0.05), and lowest for RES (5.57 ± 0.08) sheep. The apical uptake of acetate and butyrate did not differ between SHAM and RES sheep. However, NR sheep had greater in vitro apical uptake of acetate and butyrate and a higher plasma β-hydroxybutyrate concentration than RES sheep, suggesting greater absorptive capacity for NR. Differences between NR and RES were attributed to greater bicarbonate-independent, nitrate-sensitive uptake of acetate (P = 0.007), a tendency for greater bicarbonate-dependent uptake of acetate (P = 0.071), and greater bicarbonate-independent uptake of butyrate (P = 0.022). These data indicate that differences in the rates and pathways for the uptake of acetate and butyrate explain a large proportion of the individual variation observed for the severity of SARA.

^* To whom correspondence should be addressed. E-mail: aschenb{at}rz.uni-leipzig.de.

Manuscript received 9 April 2009. Initial review completed 1 May 2009. Revision accepted 2 July 2009.

Published online 29 July 2009.

This article has been cited by other articles:

				E. Khafipour, S. Li, J. C. Plaizier, and D. O. Krause Rumen Microbiome Composition Determined Using Two Nutritional Models of Subacute Ruminal Acidosis Appl. Envir. Microbiol., November 15, 2009; 75(22): 7115 - 7124. [Abstract] [Full Text] [PDF]