Review: Abdel Rahman El Gamal (Founder of the website)
The removal of the premaxilla of bone of the upper lip of tilapia males goes back to the late 1970s. The purpose of such practice is to reduce the aggressive behavior of tilapia males and hence reduce the possible injuries and/or mortality of females during the spawning season especially when the mating takes place in confined places such as hapas or tanks whereas females can be exhausted or experience scale loss that may lead to their death. This harm is more frequent when males are much larger than females. The clipping of the premaxilla is done using sharp scissors or razors.
As expected, in open pond breeding, the aggressive behavior of males is not common as females usually have more chance to escape such harassment and hence the removal of the male premaxilla is not usually required. The same is true when females are mated with similar-sized males.
The resulting wound should be disinfected using proper disinfectants such as potassium permanganate or a 10% solution of Betadine. It may worth noting that the removal of the male premaxilla does not interfere with the reproduction or feeding activities of treated males.
