[Effects of reduced food intake on digestive flux and use of nitrogenous matter by goats].
Limited feeding effects (75% of ad libitum) were studied in 3 adult dry goats. Their diet was composed of dried beet pulps (1/3 DM), dried alfalfa (1/3 DM) and hay (1/3 DM). The CP content was 11.9% DM. Rumen fermented OM was decreased by 243 g.d-1, but rumen pH and ammonia content remained the same. Rumen bacteria synthesis efficiency was decreased (-4%), but the value (151 g crude bacteria protein.kg-1 DOM) was higher than conventional values used in PDI and NRC systems. Nitrogen rumen balance (duodenal N-N intake) was lower (-1.9 g.d-1) with restricted goats. This could be related to the increase in urinary urea excretion (+0.4 gN.d-1). There was no significant effect of the limiting feeding on total OM and N digestibilities. The disappearance rate of OM in the rumen and the small intestine tended to be higher (+4 and +8%, respectively) in the restricted animals. Nitrogen retention was lower (-5.7 g.d-1) in restricted goats. Only 59 (or 56%) of the duodenal nitrogen was protein. Their digestibility in the small gut was higher (+8 pts) than NPN digestibility. A total of 86% of duodenal RNA disappeared in the small gut but less than 60% of DAPA was digested in this part.
Halbouche
M
M
Laboratoire science animale INRA-ENSAIA, Vandoeuvre, France.
Brun-Bellut
J
J
D000641:Ammonia / Q000378:metabolism; D000821:Animal Feed; D000818:Animals; D004063:Digestion / Q000502:physiology*; D005260:Female; D005285:Fermentation; D005508:Food Deprivation / Q000502:physiology*; D006041:Goats / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009584:Nitrogen / Q000378:metabolism*; D012417:Rumen / Q000502:physiology
D000641:Ammonia; D009584:Nitrogen
Influence d'une réduction des apports alimentaires sur les flux digestifs et l'utilisation des matières azotées par les Caprins.