Journal of Animal Science, Vol 72, Issue 8 2141-2148, Copyright © 1994 by American Society of Animal Science

JOURNAL ARTICLE

Influence of a propionate load in fed or unfed lambs on blood metabolites and hormone patterns

N. A. Cole and D. M. Hallford
Agricultural Research Service, USDA, Bushland, TX 79012.

Six crossbred wether lambs were used in a crossover design to determine the effects of a 3-d feed and water deprivation period on metabolite and hormonal response to a propionate load. During each period of the crossover design all lambs were limit-fed (700 g/d) a 36% concentrate diet for 16 d, then three of the six lambs were deprived of feed and water for 3 d. All lambs were then limit-fed (700 g/d) the 36% concentrate diet (realimentation). Propionate loading tests were performed 4 h before feeding on d 1, 5, and 9 of the realimentation period. A 1.84 M propionate solution (3 mmol/kg BW) was infused into the right jugular vein and blood samples were obtained from the left jugular vein at intervals for 4 h after infusion. At the end of the 3-d feed and water deprivation period, fed lambs had greater serum insulin (P < .02), acetate (P < .01), and glucose (P < .05) concentrations and lower plasma-free fatty acids (P < .01) and urea N (P < .05) concentrations than unfed lambs. On d 1 of realimentation, previously unfed lambs had greater postinfusion growth hormone (P < .05), free fatty acid (P < .01), propionate (P < .07), lactate (P < .04), and urea N (P < .05) concentrations and lower serum insulin (P < .02), and acetate (P < .03) concentrations than fed lambs. Serum prolactin concentrations increased (P < .02) postinfusion in unfed lambs but not in fed lambs.(ABSTRACT TRUNCATED AT 250 WORDS)