Long-life partners or sex friends? Impact of parental pair bond on offspring personality

Abstract Previous investigations reported that some traits of parental relationships, including pair-bond duration or mate behavioural compatibility, influence subsequent offspring fitness by acting on their behaviour, growth and thus their early survival. We hypothesized that the development of a pair-bond between sexual partners would have a prenatal influence. This study investigated the impact of two pairing managements on the egg characteristics and development of offspring of Japanese quail ( Coturnix c. japonica ). Thirty males and 30 females were paired either continuously (C) (mates together all the time) or non-continuously (NC) (pairs met only three times a week for five minutes). Separation-reunion tests evaluated parental pair bond. Egg yolk testosterone and androstenedione levels were evaluated, and the somatic and behavioural development of C and NC chicks was assessed. Our results revealed that members of C pairs were attached to their mates and, although no significant differences in androgen levels could be evidenced between egg sets, a higher proportion of C pairs9 eggs were fertilized and their chicks appeared less emotive and more social. Our results revealed that parental relationship can modulate the behavioural development of their offspring, probably via non-genetic effects, and this could play a major role in the emergence of inter-individual variability.