Back-drawer: A Behavioral Mutant in Japanese Quail

Abstract

The behavioral mutant“back-drawer”of Japanese quail is characterized by crouching and back-drawing action with the neck bending ventrally and occasional forward rolling. The abnormal behavior appears from hatching to 8 weeks of age. Back-drawers were classified into three types: (1) thouse showing the abnormality at hatching and dies within 5 days; (2) those showing the abnormality after 2 weeks of age and dies shortly thdreafter; and (3) long survivors suffering from abnormal behavior, and showing gradual recovery. Back-drawer males are infertile when showing the abnormality, but can produce progeny after recovery. In contrast, the females tend to have a short life span and lack reproductive ability. Genetic analyses have indicated that this mutant character is controlled by 2 pairs of autosomal recessive genes.