Further studies on the effect of fat supplementation of concentrates fed to lactating dairy cows. II. Total digestion and energy utilization.

Abstract

For wether sheep given 300 g hay and 800 g concentrates the addition of fat (beef tallow:palm kernel oil 9:1) to concentrates at 7 or 12% tended to decrease crude fibre digestibility and increased crude fat digestibility. For 2 rumen-fistulated cows given concentrates containing 7% fat, or 12% fat free or adsorbed on carrier, and 2 cows with fistulae and reentrant duodenal cannulae given concentrates with 12% fat in rations with hay:concentrate 1:2, there were no significant differences between diets in the digestibility of any nutrient; fat digestibility was decreased at feed intakes above maintenance, particularly with the 12% fat concentrates. The use of a carrier in the 12% fat concentrates did not affect nutrient digestibilities for sheep or cows. Inclusion of fat in concentrates increased the metabolizability of sheep diets but there were no significant differences among cattle diets, although methane losses tended to decrease as fat content increased. Additional energy from fat tended to be retained rather than used for milk yield. ME utilization for milk, storage and maintenance was 61-62.5%, tending to be highest with the 12% adsorbed fat. [See DSA 45, 5398 for part I.] (Abstract retrieved from CAB Abstracts by CABI’s permission)

Effects of blend of canola oil and palm oil on nutrient intake and digestibility, growth performance, rumen fermentation and fatty acids in goats

“…Improved crude fat digestibility with increasing level of oil supplementation occurred because as dietary fat increases, the fraction of endogenous fat excreted in the feces formed a smaller portion of the ingested fat (van der Honing et al . ). Also, Kronfeld et al .…”

Further studies on the effect of fat supplementation of concentrates fed to lactating dairy cows. 3. Effect on rumen fermentation and site of digestion of dietary components.

“…Hay was fed at 6h00 and 15h30; concentrates were offered one hour later. Compo sition of the concentrate mixtures was reported in a previous paper (van der Honing et al, 1983). Animals with only a rumen cannula received all three treatments, ani mals also equipped with duodenal cannulae received treatments C12 and C12C only.…”

“…The effect of fat supplementation was studied in dairy cows equipped with rumi nai and duodenal cannulae. With these animals energy balance studies were per formed, the results of which were reported in a previous paper (van der Honing et al, 1983). The effect on rumen fermentation and site of digestion of various dietary components is reported in this paper.…”

“…All animals were fitted with a rumen cannula and two animals were also fitted with a re-entrant can nula at the beginning of the small intestine just beyond pancreatic and bile duct. Housing, feeding and maintaining the animals was as described in a previous paper (van der Honing et al, 1983). Experimental diets were one third of long meadow hay and two thirds of one of three concentrates supplemented with 7 % of fat (treatment C7), supplemented with 12 % of fat (treatment C12) or supplemented with 12 % of fat adsorbed on a carrier of Palabora vermiculite (treatment C12C).…”

Further studies on the effect of fat supplementation of concentrates fed to lactating dairy cows. 1. Effect on feed intake, feed intake pattern and milk production and composition.

“…The mixtures were subse quently pelleted. Details on the composition of the concentrates are given in a subsequent paper (van der Honing et al, 1982). The chemical composition of the hay and the concentrates are shown in Table 1.…”