Related Experiment Video
Updated: Feb 14, 2026

Effect of Male Accessory Gland Products on Egg Laying in Gastropod Molluscs
Published on: June 22, 2014
Occurrence and Genetic Parameters Estimation of Blood and Meat Spots in Brown-Shelled Eggs During the Extended Laying
Honglei Jin1, Bingxin Luo1, Lin Xuan1
1National Engineering Laboratory for Animal Breeding and MOA Key Laboratory of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing 100193, China.
Abstract:
Blood and meat spots are key internal egg quality indicators, and clarifying their genetic characteristics in late laying periods is critical for quality improvement via selective breeding. This study collected 392 eggs from 421 96-week-old Rhode Island Red hens across 69 families, analyzing 10 traits including blood/meat spots and standard egg quality traits. Heritability, genetic and phenotypic correlations were estimated using the DMU package. The incidences of blood and meat spots were 15.8% and 64.8%, respectively. Blood spots were yolk-localized, single and <1 mm in diameter, while meat spots mostly occurred on chalazae (83.5%) and thick albumen (33.1%), mostly multiple (56.1% with 2-5 spots) and 1.80 ± 1.53 mm in diameter (30% >2 mm). Blood spots had low heritability (0.05), meat spots moderate heritability (0.20). The two traits showed high positive genetic correlation (rG = 0.93), and strong negative genetic correlations with albumen height and eggshell strength. In conclusion, blood and meat spots in late-laying hens differ in distribution, size and number, and meat spots are amenable to genetic selection for internal egg quality enhancement.
Related Concept Videos
Distributions to Estimate Population Parameter
What is Population Genetics?
Laying Concrete Masonry
Mortar application focuses on the face shells of the blocks, the sides that face outward,...
The Periodic Table
Periodic Classification of the Elements
Types of Reports II: Incident or Occurrence Report
Purposes:
In the healthcare industry, reports play a crucial role in documenting incidents within an agency. The primary objective of these reports is to ensure patient safety, uphold the...

