Shank length for determining sex in chukars

Area of Science:

• Avian Biology
• Animal Science
• Poultry Husbandry

Background:

• Accurate sex determination in chukar partridges (Alectoris chukar) is crucial for efficient management in breeding, marketing, and conservation programs.
• Traditional methods for sex differentiation can be invasive or require specialized expertise, particularly in young birds.

Purpose of the Study:

• To establish a non-invasive and accurate method for sexing chukar partridges at various developmental stages.
• To determine the optimal age for sex determination based on shank length measurements.

Main Methods:

• Measurements of shank length were taken from male and female chukar partridges at 8, 10, 12, 20, 32, and 64 weeks of age.
• Statistical analysis was performed to correlate shank length with sex and determine prediction accuracy at different ages.
• Thresholds for sex prediction were established based on shank length (e.g., >= 60 mm for males, < 60 mm for females).

Main Results:

• Shank growth is largely complete by 10 weeks of age, while body tissue growth continues until approximately 20 weeks.
• The highest accuracy for sex prediction (approximately 95%) was achieved at 10 weeks of age.
• At 10 weeks, prediction accuracy for males (98.5%) was higher than for females (93%).
• At 64 weeks, a threshold of >= 61 mm for males and < 61 mm for females provided optimal accuracy.

Conclusions:

• A single shank length measurement at 10 weeks of age provides a reliable and accurate method for differentiating sexes in chukar partridges.
• This technique offers a practical tool for growers and avian biologists for early-age sex separation, aiding in marketing, restoration, and breeder selection.