Environment and Management II

Exposing eggs multiple times to ultraviolet light (UV) and 3% hydrogen peroxide (H2O2) results in a greater reduction of eggshell bacteria compared to eggs treated only once with this combination. However, it is unknown if this repetitive treatment will have any effect on hatchability. Therefore, the objective of this experiment was to determine if hatchability would be affected by reducing eggshell bacteria with repeated use of UV and H2O2. A total of 2,208 eggs from 47 wk old broiler breeders were collected from a commercial house and transported to the lab. Half of these eggs were treated and the other half served as controls. The treated eggs were misted with H2O2 and then exposed to 2 min of UV. This procedure was repeated a total of 6 times. Thirty-six eggs per treatment were used for bacterial enumeration. The remaining eggs were weighed and placed in 8 separate incubators (4 control and 4 treated). At 18 d of incubation, the eggs were weighed to determine egg moisture loss and placed in hatching baskets. At hatch, bacterial counts in the incubator air and chick weights were determined. Also, meconium samples were obtained from 10 randomly selected chicks from each incubator to determine the presence of intestinal bacteria. All chicks from each incubator were placed into a corresponding grow out pen, one pen for each incubator. Hatch residue analysis was performed on unhatched eggs. At 5 d post hatch, yolk sacs from 20 chicks per room were removed, weighed, and yolk sac material was plated for presence of bacteria. A 4 log reduction in eggshell bacteria was observed for eggs treated with UV and H2O2 compared to control eggs. There were no differences in hatchability, hatch residue, chick weight, residual yolk weight, egg moisture loss, or bacterial presence in meconium, residual yolks, or incubator air samples between control and treated groups. In conclusion, multiple applications of UV and H2O2 effectively reduced bacteria on the eggshell with no effects on the hatchability of broiler breeder eggs.