Effect of Immunocastration Using a Gonadotropin-releasing Hormone Vaccine on Mounting Behaviour of Group-housed Male Domestic Quail(<i>Coturnix japonica domestica</i>)

The male domestic quail (Coturnix japonica domestica )shows sexually aggressive behaviour, including mounting accompanied by pulling feathers and skin on the head and neck [1].This behaviour is directed toward both female [2,3] and male [4,5] individuals.At the Kyoto City Zoo (KCZ, Kyoto, Japan), male-to-male aggressive behaviour in quails has been observed during the breeding season, which lasts from March to November when the day length is maintained at over 12 h [6].During this period, dominant hierarchies develop among quails, and subordinate individuals often experience feather loss or bleeding due to the mounting behaviour of the dominant individuals.In the case of severe feather loss and injury, affected quails require isolation and/or continuous treatment, highlighting the need for effective reproductive management