Effect of preheating fertile eggs on hatchability parameters of Ross AP950 heavy broiler breeders

Abstract

This study assessed the effect of preheating fertile eggs from Ross AP950 heavy broiler breeders on hatchability parameters. In a completely randomized design (CRD), 83,160 fertile eggs were divided into three experimental treatments: no preheating (T0), preheating at 28 °C for 4 hours (T1), and preheating at 28 °C for 8 hours (T2). The parameters assessed were hatchability percentage, the proportion of culled chicks, embryonic mortality, the weight of day-old chicks, and chick yield. Hatchability residuals did not meet the normality assumption; therefore, treatment differences were additionally assessed using the Kruskal–Wallis test followed by Dunn's pairwise comparisons with Holm adjustment. For variables meeting the assumptions of parametric analysis, one-way ANOVA followed by Tukey's test was used. Hatchability differed among treatments (Kruskal–Wallis, H = 10.97; P = 0.004). The mean hatchability was 86.61%, 87.40%, and 88.65% for T0, T1, and T2, respectively. T2 differed from both T0 and T1, whereas T0 and T1 did not differ significantly. The culled chick rate also differed among treatments (P < 0.001), decreasing from 1.67% in T0 to 1.34% and 1.26% in T1 and T2, respectively. Although there was no significant difference in embryonic mortality across the treatments (P > 0.05), a numerical decrease was noted. The control treatment achieved the highest chick yield at 70.35%, with T1 slightly lower at 69.48%, while T2 had the lowest yield at 68.75% (P < 0.05). In a similar manner, notable variations were found in the average body weight of day-old chicks (P < 0.05). The control group exhibited the greatest weight at 44.78 g, with T1 and T2 following at 44.66 g and 43.58 g, respectively. The study concludes that preheating fertile eggs at 28 °C for 8 hours enhances hatchability parameters in Ross AP950 heavy broiler breeders.