Selection of preparental lines of plymouth rock chicken using marker genes K and k

Chicken lines with marker genes of sex-linked economically important traits are of a particular breeding interest. Here we report on the first results on the creation of an autosex maternal parental form of dual purpose Plymouth Rock breed by sequential selection of chickens from experimental Russian breeding lines. The paternal and maternal pre-parental Plymouth Rock lines were selected for productivity indices and for growth rate of wing feathers. Genotypes with slow (line X4) and fast (line X3) feathering rates were maintained via phenotypic evaluation at 1 day of age and culling individuals with fast and slow feathering rate, respectively; heterozygous males and their progeny were also culled. Chicks with slow feathering rate feature poor development of tectrix and remex, the tectrix being longer or equal to the remex; chicks with fast feathering rate feature the well-developed tectrix which is shorter than the remex. The quantitative PCR technique (real-time polymerase chain reaction) was also used to identify individuals with homo- and heterozygous sex-linked K and k alleles; the analyses were performed using feather pulp samples...