Use of palm-oil by-products in chicken and rabbit feeds: effect on the fatty acid and tocol composition of meat, liver and plasma

Abstract

This study was undertaken in the framework of a larger European project dealing with the characterization of fat co-and byproducts from the food chain, available for feed uses. In this study, we compare the effects, on the fatty acid (FA) and tocol composition of chicken and rabbit tissues, of the addition to feeds of a palm fatty acid distillate, very low in trans fatty acids (TFA), and two levels of the corresponding hydrogenated by-product, containing intermediate and high levels of TFA. Thus, the experimental design included three treatments, formulated for each species, containing the three levels of TFA defined above. Obviously, due to the use of hydrogenated fats, the levels of saturated fatty acids (SFA) show clear differences between the three dietary treatments. The results show that diets high in TFA (76 g/kg fat) compared with those low in TFA (4.4 g/kg fat) led to a lower content of tocopherols and tocotrienols in tissues, although these differences were not always statistically significant, and show a different pattern for rabbit and chicken. The TFA content in meat, liver and plasma increased from low-to-high TFA feeds in both chicken and rabbit. However, the transfer ratios from feed were not proportional to the TFA levels in feeds, reflecting certain differences according to the animal species. Moreover, feeds containing fats higher in TFA induced significant changes in tissue SFA, monounsaturated fatty acids and polyunsaturated fatty acids composition, but different patterns can be described for chicken and rabbit and for each type of tissue.

Use of recovered frying oils in chicken and rabbit feeds: effect on the fatty acid and tocol composition and on the oxidation levels of meat, liver and plasma

“…Variations in the digestion process between species, their FA metabolic sites and in the activity of enzymes involved in FA metabolism between species might explain these differences (Benatmane et al, 2011;Kouba and Mourot, 2011). Furthermore, the tendency of rabbit liver to incorporate higher PUFA than chicken is consistent with our findings in animals receiving a diet that was richer in SFA, supplied through hydrogenated palm FA distillates (Tres et al, 2012).…”

Impact of the oxidative quality of fish oils in feeds on the composition and oxidative stability of chicken and rabbit meat

“…In the first part of this project, more than 120 commercial fat products were characterised (Ábalos et al, 2008;Nuchi et al, 2009;Ubhayasekera and Dutta, 2009). Those containing the highest levels of dioxins, polycyclic aromatic hydrocarbons (PAH), trans FA (Tres et al, 2012a) and oxidation compounds (Tres et al, 2012b) were selected for testing in experimental animal trials. In agreement with what has been mentioned above, fish oils were the group of fats showing the highest dioxin content and oxidation status (Ábalos et al, 2008;Nuchi et al, 2009).…”

“…For instance, the difference in the content of C22:6n-3 between FO1 and FO2 feeds (59% chicken; 52% rabbit) was significantly higher (P<0.05) than in meat (31% chicken; 26% rabbit) or liver (17% for chicken -not significant; 42% for rabbit). In order to explore this finding further, we calculated the meat-to-feed and liver-to-feed ratios by dividing the FA concentration in meat or in liver (expressed in mg per 100 g) by the FA concentration in the corresponding feed (in mg per 100 g) (as described in Tres et al, 2012a). The chicken meat-to-feed ratio for C22:6n-3 was lower in FO2 (0.725) than in FO1 (0.879) and FOM (0.878) (P<0.05).…”

Re‐esterified oils from palm acid oil do not alter pork fatty acid composition

“…However, the continued price increase in the use of supplemental conventional oils such as soybean, rapeseed, sunflower, and palm oil has led the animal production industry to find and evaluate available, cheaper, cost effective, sustainable, and reliable alternatives . This situation has led to an increased interest in utilizing and valorizing fat by‐products from the food industry as fat sources in animal feeds . For instance, fat by‐products such as acid oils are produced during oil refining and they have a certain energy value .…”

“…This situation has led to an increased interest in utilizing and valorizing fat by‐products from the food industry as fat sources in animal feeds . For instance, fat by‐products such as acid oils are produced during oil refining and they have a certain energy value . However, they are rich in free fatty acids (FFA) whose apparent metabolizable energy has been reported to be lower than that of triacylglycerols (TAG) most probably as a result of the low absorbability of saturated FFA in the intestine where they form calcium soaps.…”