Shank length for determining sex in chukars

Shank length measurement of greater than or equal to 60 mm for males and less than 60 mm for females was used to predict sexes in male and female chukar partridges (Alectoris chukar) at 8, 10, 12, 20, 32, and 64 weeks of age. Growth of the shank is nearly complete at 10 weeks of age, whereas growth of body tissue continues to about 20 weeks of age. The best prediction of sexes was made at 10 weeks of age with an accuracy of about 95%. At 10 weeks of age, the accuracy for predicting males was higher than for females (98.5% vs 93%). At 64 weeks of age, best accuracy of sexes was made using a shank measurement of greater than or equal 61 mm for males and less than 61 mm for females. This technique to differentiate between sexes requires only a single shank measurement taken at 10 weeks of age and provides the grower and avian biologist with a reliable way of separating sexes for purposes of marketing, restoration, or selection of breeders at early ages.