Differences in innate fear behaviour in native Japanese chickens.

Area of Science:

• Animal Behaviour
• Avian Genetics
• Ethology

Background:

• Understanding innate fear in chickens is crucial for adapting native breeds to modern agriculture.
• Breeding goals can influence chicken behavior, necessitating research into fear responses.

Purpose of the Study:

• To compare innate fear behavior in chicks from six native Japanese chicken breeds and two White Leghorn lines.
• To analyze fear sensitivity using tonic immobility (TI) and open field (OF) tests.

Main Methods:

• Tonic immobility (TI) and open field (OF) tests were performed on 267 chicks across eight breeds at 0-1 days old.
• Environmental factors were corrected, and breed differences were analyzed using Kruskal-Wallis and Steel Dwass post hoc tests.
• Principal component (PC) analysis was employed to classify breeds based on fear traits.

Main Results:

• Oh-Shamo (OSM) demonstrated the lowest fear sensitivity in both TI and OF tests.
• White Leghorn (WL-G) showed high TI fear sensitivity but low OF fear sensitivity.
• PC analysis grouped breeds into least (OSM, WL-G), moderate (IG, WL-T, NAG, TJI, TKU), and most sensitive (UK) fear categories.

Conclusions:

• Significant breed differences in innate fear responses were identified among native Japanese chickens and White Leghorns.
• Breed classification based on fear sensitivity provides insights into adaptation potential in different production environments.