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This experiment was conducted to study the effect of dietary vegetable oil on lipid oxidation in rabbit muscle. A control diet with no added fat and two diets with olive or sunflower oil (30 g/kg) were used. Within each treatment, one group was fed a low level of [Alpha]-tocopheryl acetate (10 mg/kg diet), and the other a supplemental level (200 mg/kg). Rabbits were fed experimental diets from weaning (20 d) to slaughter (69 d). The supplemental level of dietary [Alpha]-tocopheryl acetate produced higher [Alpha]-tocopherol concentration in muscle (P < 0.006) and lower lipid oxidation (P < 0.004). Rabbits that received sunflower oil had higher concentrations of thiobarbituric acid reactive substances than rabbits that consumed olive oil (P < 0.05). Moreover, a significant effect due to fat inclusion in the diet was found. Muscles from rabbits fed diets not enriched with fat had higher susceptibility to lipid oxidation (P < 0.005) and higher concentration of (n-3) fatty acids in polar lipids (P < 0.04) than those from rabbits fed fat-enriched diets. A second experiment was conducted and confirmed the higher lipid oxidation in the muscle of rabbits fed diets not enriched with fat than in that of rabbits fed diets containing sunflower oil (28 g/kg) (P < 0.003) as well as in diets with identical digestible energy. In this experiment, [Alpha]-tocopheryl acetate was at the lower level (10 mg/kg feed). Inclusion of oils rich in oleic (olive oil) or linoleic acid (sunflower oil) in rabbit diets reduces lipid oxidation in muscles. KEY WORDS: * rabbits * fat * feeding * oxidation

We evaluated the effects of dietary fat type on fat metabolism and deposition in broiler chickens. Birds were fed diets containing either 8 g dietary saturated (beef tallow) or polyunsaturated fat (sunflower oil)/100 g for 32 d. The abdominal fat deposition of chickens fed the sunflower oil-enriched diet was significantly lower than that of chickens fed the tallow-enriched diet (2.63 [+ or -] 0.47 versus 3.03 [+ or -] 0.44 g/100 g live wt.; P = 0.033). The specific activities of heart carnitine palmitoyltransferase I and L-3-hydroxyacyl-CoA dehydrogenase were higher (P [is less than or equal to] 0.03) in chickens fed the sunflower oil-enriched diets, indicating a greater rate of [Beta]-oxidation. Liver fatty acid synthetase activity was lower (P = 0.01) in chickens fed the sunflower oil-enriched diet, suggesting reduced hepatic lipogenesis in this group. Postprandial plasma triglyceride levels were significantly lower (P [is less than] 0.05) in birds fed the sunflower oil-enriched diet, indicating a higher rate of dietary lipid clearance from the bloodstream to tissues. In conclusion, the lower fat deposition observed in broilers fed sunflower oil-enriched diets appears to be the net result of an increased rate of lipid catabolism and lower rate of fatty acid synthesis despite higher dietary fat absorption. J. Nutr. 130: 3034-3037, 2000. KEY WORDS: * dietary fat type * lipogenesis * lipolysis * fat deposition * broiler chickens

Thirty Large White×Great York gilts were fed six experimental diets containing three levels of poly and monounsaturated fatty acids. Within each dietary fat treatment, one group was fed a basal level of vitamin E (20 mg α-tocopheryl acetate/kg diet) and the other group received a supplemented level (200 mg α-tocopheryl acetate/kg diet). Concentration of α-tocopherol was significantly higher in hams from pigs fed supplemented dietary levels of vitamin E (P<0.0001), but no significant effect of dietary fat was observed. Dietary vitamin E supplementation reduced the concentration of thiobarbituric acid reactive substances after 9 days storage of sliced samples (P<0.0001), while dietary fat source showed no significant effect. Significantly lower oxidation was observed in ham homogenates from pigs fed higher concentrations of monounsaturated fatty acids after 120 min of incubation under pro-oxidant conditions (P=0.013). No effect of dietary treatment was observed in ham volatile aldehyde profile. No significant effect of dietary vitamin E was observed on surface redness during storage, but a significant effect was observed for luminosity after 7 days of storage (P=0.033). Hams from pigs fed diets enriched in monounsaturated fatty acid showed higher ‘a’ values (P=0.040) in stored sliced samples. Sensory evaluation revealed a significant effect of dietary vitamin E on redness of ham slices (P<0.001). Dietary supplementation with vitamin E also produced a significantly higher odour and flavour intensity (P=0.006 and P=0.01 respectively). Dry cured ham samples from pigs fed higher amounts of monounsaturated fatty acids showed a significantly higher consistency fat than those from pigs fed polyunsaturated fatty acids. [Copyright &y& Elsevier]

Presents experiments which studied the effect of dietary vegetable oil on lipid oxidation in rabbit muscle. Materials and methodology of experiments; Results obtained in both experiments; Discussion of results.

The present study evaluated the effect of nutritional imbalances during pregnancy, either by excess or deficiency, on fertility and conceptus development in obese-genotype swine (Iberian pig). Twenty-five multiparous sows were fed, from mating to farrowing, with a standard diet fulfilling either 1.6 folds their daily maintenance requirements for pregnancy (overfed group, n = 12) or only the 50% of such requirements (underfed group, n = 13). Ten out of 12 overfed but only two out of 13 underfed sows became pregnant (P<0.005). Fetal development was determined in the pregnant females at Days 35, 50, 75 and 90 of pregnancy. The embryos from undernourished sows were smaller than the embryos from overfed females as early as at 35 days of pregnancy (P<0.05) and remained smaller until Day 90 of gestation. However, at the end of pregnancy, there were significant changes in the developmental patterns of fetuses. Thus, weight and size of the offspring from both nutritional treatments were finally similar at delivery; the same was found at weaning. There was thereafter a sex-related effect on the growth during the early-postnatal period, with male piglets of both nutritional origins being significantly heavier and more corpulent at weaning that their sisters (P<0.05). In conclusion, fetal growth conditioned by malnutrition from periconceptional stages is mainly regulated at the end of the pregnancy, so that ensure an adequate body-weight and size and, therefore, the survival of the offspring. Afterwards, the early-postnatal development of the offspring is affected by sex, independently from nutritional origin, with male piglets growing faster than females.