# Egg quality characteristics of South African Potchefstroom Koekoek and commercial Lohmann brown layer chickens: A comparative study

## TL;DR

This study compares egg quality traits between two chicken breeds, finding significant differences in both external and internal egg characteristics.

## Contribution

The study provides new empirical evidence on how chicken genotype influences egg quality traits in South African and commercial chicken breeds.

## Key findings

- Genotype significantly affects most external egg quality traits except unit shell surface weight.
- Lohmann Brown chickens showed better internal egg quality traits compared to Potchefstroom Koekoek chickens.
- Significant differences were observed in traits like eggshell index, yolk weight, and albumen ratio between the two genotypes.

## Abstract

Egg quality is an important feature in egg production and is affected by many factors, including the genetic makeup of the bird. However, the influence of the chicken genotype on egg quality traits is limited and inconclusive. Therefore, this study aimed to highlight the influence of genotype on the external and internal egg quality traits of the Potchefstroom Koekoek and Lohmann Brown layers. A total of 600 eggs (300 eggs per genotype) was used, and a cross-sectional experimental design was used. The findings displayed that all external egg quality traits were significantly (P < 0.05) affected by the genotype, except for the unit shell surface weight (P ≥ 0.05). The outcomes also displayed that the genotype significantly (P < 0.05) affected all internal egg quality traits. The most affected traits favored the Lohmann Brown over the Potchefstroom Koekoek chickens. In conclusion, the outcomes showed significant differences in the external egg quality traits such as the egg length, shell weight, eggshell index, egg width and shell ratio, and the significant differences in the internal egg quality traits such as yolk/ albumen, yolk weight, albumen weight, albumen ratio and yolk ratio between the Potchefstroom Koekoek and Lohmann Brown chickens.