title: [Effect on energy and nitrogen balances of replacing part of the tallow in a milk replacer for preruminant calves by tricaproin or coconut oil: effect of previous feeding level].
abstract: Using two open-circuit respiratory chambers, the effects of medium chain fatty acid intake on digestibility, energy and nitrogen balance were investigated in 4 groups of preruminant Friesian male calves. One group of 7 animals was fed a control diet with a skim-milk powder and tallow base (diet 1). The other three groups were fed diets in which one-third of the tallow was replaced by either 1/3 coconut oil (6 animals, diet 2) or 1/3 tricaproin (6 animals, diet 3). In diet 4, two-thirds of the tallow was replaced by 1/3 coconut oit + 1/3 tricaproin (5 animals). Apparent digestibility and energy metabolizability (q) were similar for diets 1, 2, 3 and significantly higher (P less than 0.05) for diet 4: 97.5 vs 95.1% for dry matter digestibility 97.3 vs 94.5% for energy digestibility, 95.6 vs 93.7% for crude protein digestibility and 94.6 vs 92.8% for q. Whatever the diet, metabolizable energy (ME) efficiency for tissue deposition was 70 +/- 9% and maintenance requirements amounted to an average of 90 kcal ME/d/kgW0.75. However, the latter were related to previous feeding level and increased by .13 +/- 0.06 kcal/d/kgW0.75 for an increase of 1 kcal/d/kgW0.75 of previous ME intake. The lipids in each of the 4 diets were also deposited at a rate of 0.40 +/- 0.09 kcal. Lipid gain was decreased by 0.12 +/- 0.08 kcal for an increase of 1 kcal/d/kgW0.75 of previous Me intake. The regression coefficients of protein energy gain on Me intake were 0.25 +/- 0.01; 0.25 +/- 0.06; 0.30 +/- 0.04 and 0.29 +/- 0.06 kcal PF/kcal of ME, respectively, for protein gain did not depend on the previous level of ME intake. Finally, for each of the four diets, respective adjusted energy gains were 107.5a; 122.6b; 105.6a and 99.1a kcal/d/kgW0.75, adjusted lipid gains 60.4a; 69.0a; 50.9b and 42.6c kcal/d/kgW0.75 and adjusted protein gains 47.6a; 53.6b; 53.8b and 57.5c kcal/d/kgW0.75 (data with a different superscript are significantly different; P less than 0.05). In the present study, the energy cost of protein deposition amounted to 2.29 +/- 0.21 kcal ME/kcal of protein and that of lipid deposition to 0.99 +/- 0.20 kcal ME/kcal of lipid.
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D004041:Dietary Fats / Q000494:pharmacology*; D004734:Energy Metabolism / Q000187:drug effects*; D005526:Food, Formulated; D008297:Male; D008892:Milk; D009584:Nitrogen / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism
chemical_list: D004041:Dietary Fats; D011506:Proteins; D009584:Nitrogen
vernacular_title: Influence du remplacement d'une partie du suif d'un aliment d'allaitement par de la tricaproïne ou de l'huile de coprah, sur l'utilisation de l'énergie et de l'azote par le veau préruminant; influence du niveau d'alimentation antérieur.