Rumen succinate production may ameliorate the effects of cobalt-vitamin B-12 deficiency on methylmalonyl CoA mutase in sheep.
When lambs were fed a cobalt-deficient whole barley diet there was a rapid and massive increase in rumen succinate concentrations. Within 2 d of feeding the Co-deficient diet, the rumen succinate concentrations rose 200-fold and peaked at a level 1000-fold higher than that in Co-sufficient controls. Rumen propionate concentrations decreased, suggesting that an alteration in the balance between succinate- and propionate-producing microorganisms had occurred. The rumen succinate can be absorbed and thus may lead to elevated plasma succinate concentrations in Co-deficient animals, whether fed barley or grass. Thus, the absorbed succinate can at least partially overcome the effect on gluconeogenesis of a decreased activity of methylmalonyl CoA mutase induced by Co-deficiency. These findings suggest that impaired propionate metabolism may not be the primary metabolic defect in ovine Co-deficiency.
Kennedy
D G
DG
Department of Biochemistry, Veterinary Research Laboratories, Belfast, Northern Ireland, United Kingdom.
Young
P B
PB
McCaughey
W J
WJ
Kennedy
S
S
Blanchflower
W J
WJ
D000042:Absorption; D000730:Androstadienes / Q000378:metabolism; D000818:Animals; D003035:Cobalt / Q000008:administration & dosage / Q000172:deficiency*; D000068298:Fluticasone; D005943:Gluconeogenesis; D008764:Methylmalonic Acid / Q000097:blood; D008765:Methylmalonyl-CoA Mutase / Q000378:metabolism*; D012417:Rumen / Q000378:metabolism*; D012756:Sheep / Q000378:metabolism*; D013386:Succinates / Q000097:blood / Q000378:metabolism*; D019802:Succinic Acid; D014806:Vitamin B 12 Deficiency / Q000378:metabolism*
D000730:Androstadienes; D013386:Succinates; D003035:Cobalt; D008764:Methylmalonic Acid; D019802:Succinic Acid; D000068298:Fluticasone; D008765:Methylmalonyl-CoA Mutase