Effects of prestorage application of propolis and storage time on eggshell microbial activity, hatchability, and chick performance in Japanese quail (Coturnix coturnix japonica) eggs

Propolis, a resinous mixture produced by honeybees from substances collected from plants, has strong antibacterial and antifungal properties. The purpose of the current study was to establish the effects of prestorage application of propolis and storage time on eggshell microbial activity, egg weight loss, hatchability, and chick performance in quail hatching eggs. Treatments were compared in a 2 x 5 factorial design with 2 different storage times (7 and 14 d) and 5 prestorage applications (control, ethyl alcohol 70%, 5% propolis, 10% propolis, and 15% propolis solution). After application, the eggs were stored for 7 or 14 d at 13 C and 75 to 80% RH before incubation. Eggs sprayed with propolis had lower levels of total aerobic mesophilic bacteria, coliform, Salmonella spp., Staphylococcus spp., and mold yeasts than control eggs over the storage period and incubation period. Microbial activity in eggs stored for 7 d was significantly higher than in eggs stored for 14 d at the end of the storage. The lowest egg weight loss during storage was obtained in P15 treatment eggs stored for 7 d, whereas the highest egg weight loss was found in the treatment A after storage for 14 d. Although propolis treatment at 3 different doses was not effective on relative growth, only P15 decreased the BW at d 10, compared with the control. Hatchability in eggs stored for 14 d was significantly lower than in eggs stored for 7 d. No significant differences were observed for hatchability and embryonic mortality among propolis treatment groups. Propolis did not have a detrimental effect on hatchability, embryonic mortality, or BW gain. Our results indicate that propolis may be used to effectively reduce microbial activity on the surface of quail hatching eggs during storage and incubation without any detrimental effects on hatchability.