Influence of Shape Index, Specific Gravity, Area-Volume Ratio, and Egg Weight Loss During Incubation on the Hatchability of Eggs from Layer Hen Grandparents

Abstract

ABSTRACT The physical parameters of eggs significantly impact embryo development and hatching success. This study aimed to examine the influence of the egg shape index (SI), specific gravity (SG), weight loss (WL), and area-volume ratio (AV) on hatching eggs from brown-layer hen grandparents. A total of 7,500 eggs were randomly selected from two batches of Lohmann Brown grandparents at various ages (39, 44, 50, 58, and 66 weeks). SG was determined by flotation (1,070 to 1,090 g/L), while egg length, width, and weight were measured digitally. Each egg was tracked to determine hatching success, with unhatched eggs collected for embryonic diagnosis. Physical parameters were categorized into minor, intermediate, and major groups, based on viability frequency; and embryonic mortality was analyzed using the chi-square test and odds ratio (OR). The study found a lower probability of embryo death in eggs with intermediate SI (75.1% to 79%) and AV (1.01 cm²/cm³ to 1.04 cm²/cm³). No significant differences were observed between SG and WL groups. SI proved to be a reliable parameter for assessing egg quality and predicting hatchability.

Keywords

• Eggs’ characteristics
• Embryo
• Hatchery
• Layer hens