Influence of Dietary Fat on Energy Utilization by Laying Hens

Abstract

Feed grade fat was included at levels of 2 to 6% in corn-based laying hen rations and at levels of 3 to 6% in laying hen rations containing 8% wheat middlings. Added fat did not affect rate of egg production or average egg weight during the 196-day experiments. Feed consumption and efficiency of feed utilization were improved by added fat. Ration metabolizable energy (ME), as measured experimentally, was increased more than expected on the basis of commonly accepted ME values of feed grade fat when fat levels of 4 and 6% were used in cornbased rations. This effect of fat was most pronounced with the rations containing 8% wheat middlings. Assuming that the entire increase in ration ME's associated with added fat was due to fat per se, estimates of the ME content of fat were 8675 and 9015 mcal/kg when used in cornbased rations. When used in the ration containing 8% wheat middlings, the apparent ME of fat exceeded its gross energy content considerably, indicating an interaction effect between added fat and ingredient composition of the ration. Dietary fat level did not change the proportion of ME consumed that was converted to egg energy. Dietary ME to egg energy conversions ranged from 25.7 to 27.9%. The proportion of ME used for weight gain was increased slightly by added fat while no consistent changes in energy estimated as heat increment were observed.1979 Poultry Science 58:900-905

Nutritional evaluation of triple low rapeseed products for growing pigs

“…Two possible causes of this apparent improvement have been suggested. Although ME values of fat exceeding their GE have been reported in experiments with various classes of poultry, where either or both of these factors have been implicated (Cullen, Rasmussen and Wilder, 1962;Gomez and Polin, 1974;Sibbald and Kramer, 1977;Sell, Tenesaca and Bales, 1979;Mateos and Sell, 1980a), reasons for this observation in the present experiment are not apparent. Secondly, an improvement in the absorption of the non-oil component of the basal diet by the added oil is possible (Gomez and Polin, 1974;Mateos and Sell, 1980 b, c and d).…”

Effect of Four Levels of Added Fat on Broiler Breeder Performance

“…However, the calculated ME value for the corn-soybean basal diet probably overestimated the true ME for broiler breeders, because broiler breeders appear to be able to derive less ME from a corn-soybean diet than Leghorn hens, which have been used for estimating ME of feedstuffs (Spratt and Leeson, 1987a). Conversely, Sell et al (1979) have shown that the ME value for the added fat diets were probably underestimated, because added fat increases the ME value of omer energy components, producing an extra-caloric effect. Nevertheless, the ME intakes fall within the range of previously reported optimal intakes.…”

The Effect of Bile Acid on Lipid and Nitrogen Retention, Carcass Composition, and Dietary Metabolizable Energy in Very Young Chicks ,

“…This overall trend was reflected in rising AME values. The ME values of dietary fats were reported to exceed theoretical limits (Cullen et al, 1962;Gomez and Polin, 1974;Sibbald and Kramer, 1977;Sell et al, 1979;Mateos and Sell, 1981a) or to exert an extrametabolic effect (Mateos and Sell, 1981a) reflected in improved efficiencies of growth (Jensen et al, 1970). Most investigators attributed this extra value of dietary lipids to be due to an enhanced absorption of nonlipid, dietary components.…”