Effect of glycerol on the growing performance of broilers and on the nutrient content of meat, as well as apparent metabolizable energy content of glycerol in the nutrition of broiler chickens

The experiment was conducted with broilers to determine the utilisation of glycerol derived from biofuel by-product and the effect of different doses of glycerol supplementation on growing performance (weight gain, feed, energy and protein utilisation) and the chemical composition of breast and thigh meat. A total of 300 Ross 308 genotype cocks was divided into 3 groups and their diets were supplemented with 0, 5 or 10% glycerol. The AMEN content of the fed glycerol was evaluated in a metabolism experiment which was carried out with 24 birds. The apparent metabolizable energy content of the feed grade glycerol (86.3%) was assessed as 13.47 MJ/kg, which represents 93.2% of the GE. During the whole trial the dose of 5 and 10% glycerol increased the feed intake of birds by 21.4 and 16.2%, respectively. The feed consumption rose to a larger extent in the first 3 weeks than in the second part (4-6 weeks) of the trial. In consequence of the higher feed consumption the average live weight of the animals fed 5 or 10% glycerol was 2445 and 2459 g (respectively) at the end of the trial (42 days of age). The values were 13.5 and 14.1% significantly higher compared to the control group (2154 g). In the case of feed, energy and protein utilisation 10% glycerol supplementation achieved the most favourable values, but only small differences were found between the results of the 3 treatments. Glycerol addition did not affect the protein, fat and ash content of breast and thigh meat. Further dietary glycerol influenced the fatty acid profile of meats (breast and thigh) slightly.