In vitro production of beta-hydroxybutyrate from 1,3-butanediol by bovine liver, rumen mucosa, and kidney.
A model ketosis can be produced in dairy cows by restricting feed intake plus feeding 1,3-butanediol. Increases in D-beta-hydroxybutyrate in blood result from metabolism of the 1,3-butanediol, but the site of metabolism has not been established. In vitro production of D-beta-hydroxybutyrate from butyrate and from isomers of 1,3-butanediol was measured in bovine liver, rumen papillae, and kidney cortex, all obtained at slaughter from nonlactating, nonpregnant Holstein cows. Production of D-beta-hydroxybutyrate from butyrate by the tissues was greatest for liver and rumen and much less for kidney. Only liver, however, produced appreciable amounts of D-beta-hydroxybutyrate from R-, S-, or RS-1,3-butanediol, and rates were maximal at substrate concentrations of 5 mM. Production of D-beta-hydroxybutyrate from R-1,3-butanediol by liver was greater than from S-1,3-butanediol. In vitro rates of production of D-beta-hydroxybutyrate were consistent with liver being the primary tissue involved in the metabolism of 1,3-butanediol, and capacity of the liver probably is sufficient to account for metabolism of 1,3-butanediol when 1 kg is fed daily to dairy cows.
Drackley
J K
JK
Department of Animal Science, Iowa State University, Ames 50011.
Richard
M J
MJ
Young
J W
JW
D020155:3-Hydroxybutyric Acid; D000818:Animals; D002072:Butylene Glycols / Q000378:metabolism*; D002417:Cattle; D046508:Culture Techniques; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D006885:Hydroxybutyrates / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D012417:Rumen / Q000378:metabolism*
D002072:Butylene Glycols; D006885:Hydroxybutyrates; C028491:1,3-butylene glycol; D020155:3-Hydroxybutyric Acid