To browse Academia. Hybridization aims at combining valuable traits from two species into a single group. Nile tilapia Oreochromis niloticus NT and Black-chinned tilapia Sarotherodon melanotheron BCT are respectively characterized by fast growth and water salinity tolerance which attract the breeders who could take advantage of both species.
The first step is to characterize both species behavior in different contexts. The aim of this study was to compare the self-feeding behaviour between NT and BCT with a design allowing to reveal individual and group feed demand behaviour and then to identify the individual specialization that builds around the device and the food dispenser. The second objective was to estimate the links between the individual specialization and personality traits.
Personality traits of all individuals were subsequently characterized with an open field test OFT. The links between feeddemand and personality were then analyzed. Growth performances were not significantly different between NT and BCT but there was a strong tank effect. The individual specialization was similar in NT and BCT and similar to that previously observed in sea bass i. Most NT individuals stayed in the shelter during the open field test while most of BCT individuals moved out of it.
Linking the results of the self-feeding experiment and OFT in BCT, we found a strong positive correlation between the triggering activity and females' shyness. Fish that spent more time inside than outside the shelter and which latency to emerge from shelter was longer, were characterized by a higher triggering activity high-triggering fish.
This study confirms the NT ability to use self-feeder devices and provides the first insight into the same ability in BCT and demonstrates links with personality traits. Fish social behavior can be affected by artificial environments, particularly by factors that act upon species that show aggressive behavior to set social rank hierarchy. Although aggressive interactions are part of the natural behavior in fish, if constant and intense, such interactions can cause severe body injuries, increase energy expenditure, and lead the animals to suffer from social stress.
