In poultry, female individual is heterogametic having only one X-chromosome (XO condition) and male is homogametic having two X-chromosomes (XX). Therefore, inheritance pattern in relation to sex will be reversed in this case. Barred plumage is a popular example of sex linked character in poultry. In an individual, which has barred plumage, feathers are banded with bars of black on a white background (Fig. 16.11). Reciprocal crosses using this character will be discussed in this section.

Fig. 16.11. Barred and black plumage in poultry.

Barred ♀ x black ♂. If barred (B-)female individual is crossed with black male (bb)individual, (barred is normal and dominant over black), only barred males and black females are obtained in F₁ generation. When these are intercrossed and F₂ progeny is raised, barred and black individuals appear in 1 : 1 ratio, among male as well as female populations (Fig. 16.12).

Fig. 16.12. Inheritance of plumage character in poultry in a cross barred ♀ x black ♂.

Fig. 16.13. Inheritance of plumage character in poultry in a cross black ♀ x barred ♂.

Black ♀ x barred ♂. When black female individual (b-) is crossed with barred male (BB), all progeny (male as well as female) would be barred in F, generation. In F₂ generation barred and black individuals would be found in 1 : 1 ratio among female population. All F₂ male individuals would be barred (Fig. 16.13).