Abstract

Ten goats were deprived of food for 26 h and then given an intraruminal load of a buffered solution of 159±5 mM volatile fatty acids (VFA), isotonic saline or water. The weight of the load (with a volume of 3.1±0.11) corresponded to 7.5% of body weight. The results were compared with animals fed 2 h before an intraruminal load of saline or water (control) was given. During food deprivation plasma Na and rumen osmolality decreased, but total plasma protein concentration and rumen fluid Na concentration increased. After an intraruminal load of saline or water, total plasma protein concentration decreased in goats that had been fed 2 h previously. In food-deprived goats, plasma protein concentration remained elevated 5 h after a water or VFA load, but saline loads restored plasma protein concentration to pre-starvation values. The transfer of tritiated water (HTO) across the rumen epithelium of food-deprived goats given a load of VFA, saline or water was less than in controls. VFA loads gave rise to higher rates of HTO transfer then saline or water. VFA slightly stimulated blood flow to the epithelium of the rumen. Plasma renin activity increased during food deprivation, and remained elevated after a water or VFA load, but fell towards pre-starvation values after a saline load. It is concluded that Na absorption from the rumen was impaired by food deprivation. An intra-ruminal load of VFA increased HTO diffusion across the rumen epithelium and restored plasma Na concentration, but did not restore the plasma volume of food-deprived goats.

Published in

Small Ruminant Research
1990, Volume: 3, number: 6, pages: 604593
Publisher: ELSEVIER SCIENCE BV

SLU Authors

• Holtenius, Kjell

  • Department of Animal Physiology, Swedish University of Agricultural Sciences
    

• Dahlborn, Kristina

  • Department of Animal Physiology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Animal and Dairy Science


Publication identifier

DOI: https://doi.org/10.1016/0921-4488(90)90054-A

Permanent link to this page (URI)

https://res.slu.se/id/publ/86635