The sampling of 50 μl of the yolk (average 1.7% of the total volume) from northern bobwhite quail (Colinus virginianus) eggs on day 0, 6, 12, and 18 of incubation resulted in significantly (P < 0.05) increased embryo mortality in the day 12 and day 18 egg groups. Performance parameters and reproductive indices of the non-sampled eggs and the eggs sampled on day 0, and 6 of incubation did not differ from other reports on C. virginianus. No difference was found in postnatal responsiveness among hatchlings originating from controls and from all the groups of sampled eggs. As demonstrated in this representative gallifonn species, the technique can be applied for the screening of unembryonated eggs or early-embryogenesis-eggs of wild birds. If female birds are not accessible but their eggs are, information on the reproductive flock can be accessed without stressing adult birds.