N. Ceylan

L-carnitine and its functional effects in poultry nutrition

L-carnitine has indispensable functions in intermediary metabolism and is received by endogenous synthesis and from exogenous sources. It plays an obligate role in fatty acid metabolism by directing fatty acids into the mitochondrial oxidative pathway through the action of specialised acyltransferases. In poultry production, L-carnitine has a multi functional purpose, which includes: growth promotion, strengthening the immune system, antioxidant effects and improving semen quality. The concentration of L-carnitine in animals varies widely across species, tissue type, and nutritional status of the animal. It has been suggested that the L-carnitine requirement may be increased under certain circumstances such as via higher performance, various stress conditions and where the diet is deficient in animal protein sources. The review of L-carnitine functions uniquely includes the main aspects of this consequential feed supplementary inclusion in poultry nutrition.

Effects of Dietary Inclusion of Oil Sources With or Without Vitamin E on Body Composition and Meat Oxidation Level in Broilers

ABSTRACT The objective of this study was to investigate the effects of rapeseed oil substitution and vitamin E supplemantation on performance and meat quality. 4 replacement levels of rapeseed oil with sunflower oil ( 0, 33.3 , 66.7 and 100%) and 2 levels of vitamin E (0 (50 I.U. from vitamin premix) 300 mg/kg) in a 2 x 3 factorial arrangement for a total of 8 treatments with 4 replicates each, containing 10 day-old male Ross 308 broilers, were examined in the experiment. Dietary treatments had no significant effect on carcass parameters, feed conversion (FCR) and mortality (p>0.05). However, a significant interaction was observed between oil replacement and vitamin E: the negative effect of 100% sunflower oil on BWG (p<0.01) was alleviated by the addition of vitamin E. On the other hand, inclusion of rapeseed oil improved BWG (p<0.01). Rapeseed oil substitution significantly increased amount of total n-3 PUFA and decreased n-6:n-3 ratio in thigh and breast meat (p<0.01). Vitamin E supplemantation contributed to deposition of n-3 PUFA (p<0.01). Replacement of rapeseed oil without vitamin E tended to increase (p<0.01) malonaldehyde production. However, the dietary supplementation of vitamin E markedly (p<0.01) decreased the susceptibility of meat to peroxidation. Inclusion of rapeseed oil did not cause any negative perception on olfactory, texture, and taste of broiler meat. So, it can be concluded that rapeseed oil substitution significantly increased n-3 PUFA deposition without altering performance and sensory properties of broiler meat and, vitamin E had strong potential to prevent the meat lipids from oxidation.