Effects of dietary glycerol addition on growth performance, carcass traits and fatty acid distribution in cloacal fat in broiler chickens

The effects of dietary inclusion of methanol free glycerol as biodiesel byproduct at 5% or 10% were examined on weight growth, carcass traits and fatty acid distribution of cloacal fat in broiler chickens. For this aim, a total of 270 one-day-old Ross 308 broiler chickens were randomly divided into 3 equal groups according to the glycerol amounts included into diets [0% (control group fed with basal diets), 5% and 10%] for 42 days. Growth parameters (body weights, weight gains), food consumption and efficiency were weekly evaluated and carcass traits (carcass yield, intestinal pH, relative weights of heart, spleen, liver, stomach, gizzard and cloacal fat) as well as the fatty acid distribution in cloacal fat were determined at the end of the trial. Weight growth was significantly increased in treated birds, particularly in those supplemented with 5% glycerol. The glycerol supplementation has slightly improved food efficiency especially at the 4th week at the level of 5% (P < 0.05) and the carcass traits, particularly the relative weights of heart, liver and gizzard (P < 0.05). By contrast, cloacal fat composition in fatty acids was not modified by the glycerol dietary inclusion. These results show that glycerol may be incorporated into broiler diets at least at 5% without compromising growth and carcass traits.