INJECTION OF GLYCOSAMINOGLYCANS AND VITAMIN C IN INCUBATION ON THE WEIGHT LOSS AND SHELL CONDUCTANCE OF THE EGGS
Injection of nutrients into eggs can improve the incubation process. This study injected different percentages of a supplement consisting of glycosaminoglycans and vitamin C into eggs and evaluated the effect during incubation on weight loss and shell conductance of the eggs. Two hundred forty (240) fertile broiler (Cobb®) eggs from breeder hens at 43 weeks of age were used. The eggs were 64 ± 4 grams each. The experimental design was completely randomized with five treatments (non-injected eggs, eggs injected with milli-Q water, eggs injected with glycosaminoglycans and vitamin C at percentages of 2%, 4% and 6% diluted with 100 ul of milli-Q water), distributed in three horizontal Ecological Premium, model IP 120, incubators, with three repetitions and 16 eggs per treatment. Each 100 grams of the supplement were composed of: 30,000 mg of chondroitin sulfate, 30,000 mg of glucosamine and 5,000 mg of vitamin C and vehicle q.s 100 grams. The supplement was injected into the albumen, approximately six mm below the eggshell on the fourth day of incubation. The injection site was then covered with a label identifying the treatment and repetition. Statistical analsyses were performed using the Statistical Analysis System SAS®(2002) program with the averages compared by Tukey test at 5% probability. The weight loss was calculated as a percent from the difference between the weight of the egg at the start of the incubation and at day 18 days of incubation. Shell conductance was calculated by weight loss in grams until the transfer/saturation vapor pressure (23.86 mm/Hg at 25°C). Shell conductance is the ability to exchange gases between the egg and the environment, and is related to the weight loss. The higher the conductance and loss of mass, the greater the evaporative heat loss from the egg will be. In this study, the weight loss was approximately 7.6% and conductance was 0.320 and both were not significantly affected (P> 0.05) by the treatments. Therefore, the intra-egg injection of the glycosaminoglycans and vitamin C supplement did not alter the heat loss from evaporation.
Keywords: ascorbic acid, chondroitin, nutrition in ovo