Influence of incubation temperature on emu (dromaius novaehollandiae) egg hatchability

The study was conducted to assess an effect of incubation temperature (97.5 degrees F, 98.0 degrees F and 98.5 degrees F) on hatching performance of emu eggs. A total of 150 eggs were divided into 3 equal groups (1, 2 and 3) differing in the incubation temperature (97.5 degrees F, 98.0 degrees F and 98.5 degrees F in dry bulb respectively). Significant differences between the groups were observed for dead in shell. Raising the temperature to 98 degrees F in G 2 and 98.5 degrees F in G 3 led to reduce hatchability indices, primarily due to an increased rate of embryonic mortality found in both groups. Significantly different (P<0.05) mean +/- SE % of total egg hatchability and fertile egg hatchability were observed for G 1, G 2 and G 3, respectively. The mean +/- SE incubation period (days) were 50.11 +/- 0.66, 49.87 +/- 0.12 and 49.77 +/- 0.13 for G 1, G 2 and G 3, respectively. The shortest incubation period recorded in this study was 49.77 days (G 3) at highest incubation temperature (98.5 degrees F), while highest incubation period was 50.11 days at lowest incubation temperature (97.5 degrees F). A reversed trend was observed in hatching time, which expanded, in G 2 and G 3, compared with G 1. From this study, it can be concluded that the best hatching performance was achieved at 97.5 degrees F (G1) incubation temperature. Application of higher incubation temperature led to increased % of dead embryos, decreased hatchability, shortened the duration of artificial incubation and increased hatching duration.