Effects of male to female Japanese quail (Coturnix japonica) interactions on females plumage and skin condition

The high incidence of aggression in mature domestic birds is a major concern for the poultry industry. In Japanese quails, an overall score on female plumage condition was proposed to identify whether their male partner showed an aggressive profile towards them. This study delves further into the relationship between aggressive and/or sexual male Japanese quail performances and the plumage and skin condition of their female counterparts. We used an original "more rigorous" scoring system and a single female body areas approach, aiming to easily identify specific regions that are predominantly affected by male ' s aggressive and/or sexual behavior and could be used to predict male ' s performance. Additionally, this study investigates whether deteriorations in female plumage and skin condition induced by males when paired with a single female (1 male and 1 female) for pedigree purposes can also be similarly evidenced when females are housed for multiplication purposes in groups of 4 every 1 male. After 60 days of cohabitation, males were classified as low or highly aggressive based on the number of pecks recorded, and female skin and plumage status was evaluated. The study found significant positive correlations between male pecking and female's head and neck plumage and skin status, but no correlation between male sexual behaviors and female plumage and skin status. Using the male classification according to the extreme aggressive performance towards their female mate, females housed with highly aggressive males had worse neck plumage and head and neck skin status than females housed with low aggressive males. In addition, these highly aggressive males initiated more copulation sequences but achieved the same number of cloacal contacts as low-aggressive males. Regarding groups, highly aggressive males continued to express aggressive behaviors more frequently to the 4 females than those classified as low aggressive. It was observed that the female group housed with highly aggressive males had worse head plumage status than those housed with low aggressive males. Our findings suggest that the level of male aggressiveness can be discerned by examining the condition of the females' head and neck plumage, irrespective of whether they are housed in pairs