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Published on: September 20, 2021
Breeder age outweighs egg grading method on hatchability and chick quality in broiler hatcheries
Jumara Coelho Ticiano1,2, Roberto Carlos de Freitas3, Luzianna Macedo Fonseca4
1Department of Animal Science, School of Animal Science and Food Engineering (FZEA), University of São Paulo (USP), Pirassununga, SP, Brazil.
Abstract:
Incubation efficiency and chick health are fundamentally linked to fertile egg quality, which is influenced by both grading methods and breeder age. This study evaluated the effects of manual versus automated grading and Cobb breeder age (28-42, 43-56, and 57-70 weeks) on hatchability, chick quality, and embryonic mortality. The study was conducted in a commercial hatchery and a total of 54,432 fertile eggs were incubated and distributed in a completely randomized design in a 2 × 3 factorial scheme (two sorting methods × three age groups). Egg quality was first assessed by identifying cracked, dirty, inverted, and rejected eggs. Post-incubation, the study evaluated hatchability and chick quality (categorized into first and second grades). A detailed embryo diagnosis was performed to determine the incidence of rejects, embryonic mortality by stage, and the presence of live or dead pecked eggs. Data were statistically analyzed to evaluate the influence of classification methods and breeder age on key production performance indicators. This study revealed that breeder age significantly affected hatchability and incubation performance. Younger breeder hens demonstrated higher hatchability rates, whereas eggs from older breeder hens exhibited reduced incubation efficiency. In contrast, automated and manual grading systems showed comparable hatchability performance, with no significant differences observed between classification methods. These findings indicate that automated grading may be applied without negatively affecting hatchability outcomes across different breeder age groups.

