In ovo injection of bee pollen extract on hatchability, chick quality, glycogen reserves and production performance in broiler chickens.

This study aimed to investigate the effects of in ovo injection of bee pollen (BP) extract on some hatching traits, glycogen reserves and production performance in broilers. A total of 886 eggs was randomly assigned to 5 treatments: the 0.9% NaCl diluent-injected control group, and the groups that were injected with BP extract at 3 different concentrations: BP-1.5%, BP-2.5% and BP-5.0% (7, 12 and 25 mg/egg, respectively). The last group received a carbohydrate solution (CS). At 18 d of incubation, 500 µL of each solution was injected into the air sac of each egg of the injected groups. After hatching, a total of 570 one-day-old chicks were distributed into 5 groups (in ovo injection) with 3 replicates with 38 birds. The in ovo injection of BP at a dose of 5% and CS resulted in lower hatching rates (P < 0.05) as compared with the control group. The level of glycogen in the muscle tissue of newly hatched birds was not significantly different (P > 0.05). Supplementation of embryos with BP extract also caused a significant increase in the length of chicks in the BP-1.5% group (P < 0.001). Hatched chicks from the injected eggs had a lower liver glycogen content than that of the control. Based on the results, it was concluded that high-quality day-old chicks could be obtained by in ovo injection. Supplementation of chicks with 1.5% BP extract had a beneficial effect on BW during the first rearing period and showed a hypocholesterolemic effect in young chicks. At the same time, an adverse effect of a high dose of BP (5%) and a carbohydrate solution administered in ovo on the hatchability level of chicks was shown. The implementation of the carbohydrate mixture resulted in a deterioration of biochemical indices in the plasma of newly hatched chicks, especially in the case of transaminase activity.