Chickens have 39 pairs of chromosomes. Each pair of chromosomes is nearly identical in the genes that they carry and the pair of chromosomes are known as 'homologous chromosomes' or 'chromatids'. The exception to this rule is the sex-chromosomes, Z and W, where roosters have two Z chromosomes and hens have only one Z chromosome, plus one W chromosome. It is this difference in the sex chromosomes that result in sex-linked characteristics. Each chromosome contains many genes. The location or position along a chromosome where a gene may be found in its locus. "Alleles" are the alternate genes possible on a specific locus. Jacquie Jacob from the University of Kentucky will discuss the basics of poultry genetics. This information is essential if you are interested in breeding chickens.
Recording available at https://youtu.be/Z0qqGFn3Jno
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