Influence of personality traits on reproduction and sperm quality of Oreochromis Niloticus

Abstract

The aim of this study was to evaluate the reproductive aspects of Nile tilapiaclassified by personality traits. Through the environment test 16 males (8 Bold – BM and 8 Shy – SM) (110.5 ± 23.8 g) and 32 females (16 Bold – BF and 16 Shy – SF) (87.5 ± 19.3 g) were microchipped. Every seven days, were selected and relocated in mating tanks at a 2:1 female:male ratio, according to the treatments: BFBM, BFSM, SFBM and SFSM. The breeding management lasted eight weeks, after which semen was collected and analyzed, using CASA software. Offspring resistance was tested after complete absorption of the yolk sac by air exposure . Breeders of the same personality traits spawned more frequently, with the greatest amount of spawning being for BFBM and the lowest for BFSM. Total and relative fecundity were higher for SF. However, the percentage of newly hatched larvae, egg weight and volume of yolk sac were higher for BF. In males, only the Curvilinear Velocity and Straight-line Velocity were influenced by personality traits. The offspring of BF showed greater resistance to the stress test. Personality traits have an influence on reproductive parameters related to females than to males.