During the storage irreversible changes
occur in eggs that result in a deterioration of their qual-
ity. The most significant changes affect the albumen.
One of the major proteins of albumen present in egg
white is lysozyme, which protects the embryo from
microorganisms. This enzyme also contributes to the
qualitative characteristics of albumen. It is possible that
its polymorphism also affects the quality and stability of
the obtained raw material that is, table eggs. Therefore,
the aim of this study was to assess the potential effect of
polymorphism in the lysozyme gene and protein on the
quality changes during the storage of eggs derived from
2 genetic strains of Japanese quail belonging to various
utility types. Eggs from selected females of laying and
meat-type breeds were stored for 14 wk. During this
period the egg quality traits were evaluated 10 times.
DNA was isolated from each female and all exons of the
lysozyme gene had been sequenced. In total, fourteen
SNPs’ and one 4-bp indel mutation were identified in
exons and adjacent intronic sequences, among which
SNP1 (1:32140723) resulted in a substitution of lysine
with glutamine (Q21K). The results showed that SNP1
(strain S22), as well as the SNP2, SNP5, SNP7, SNP8,
SNP10, SNP11, SNP12 and SNP13 were significantly
associated with breaking strength during egg storage in
both investigated Japanese quail strains. Furthermore,
a 3 haplotype blocks containing nine SNPs (2, 5, 6, 7, 8,
10, 11, 12 and 13) were identified. These blocks dis-
played 8 distinct haplotypes that had significant associa-
tion with breaking strength at all storage time points
where egg quality analyses were performed. The study
also revealed significant effects of breed and storage time
on the egg quality traits. These results provide new
insights into the genetic basis of egg quality during stor-
age and could be incorporated into the breeding pro-
grams involving these strains.