The Rhamdia quelen is fish species with good commercial acceptance, as well as easy adaptation and management, important aspects to intensification of fish production, so that, studies to improve the technique of artificial reproduction are necessary, such as the sperm motility, characteristic extremely important and directly related at success of fish fertilization. The aim will be to evaluate the Rhamdia quelen sperm quality using fructose, glucose, sucrose, sodium bicarbonate and sodium chloride in the concentrations of 40, 80 and 120mM, respectively, as sperm activators. The male will be obtained from commercial fish farms and fed with commercial feed (36% of CP). In the reproductive season, 12 fish will be selected for reproduction, being hormonally induced by a single dosage applied to the dorsal region, a total 2.5 mg of crude pituitary carp extract - CPCE.kg-1. The gametes will be collected after a period of 240 accumulated thermal units (degree-hours), counted from the hormonal application. The semen of 12 males will be separated in three pools of four males. Each pool will be considered as replicate in the random experimental design with 16 treatments, being the different activation solutions of fructose, glucose, sucrose, sodium bicarbonate and sodium chloride in the concentrations of 40, 80 and 120mM, and the control (destilled water). To fresh semen (not activated) the sperm concentration, pH, membrane integrity, plasma osmolality and sperm morphological rates will be evaluated. After activation with different solutions the percentage of sperm motility, curvilinear velocity, average path velocity, straight line velocity, straightness, wobble, progression and beat cross frequency will be performed. These sperm parameters will be evaluated by IMAGEJ software/plugin CASA (Computer Assisted Sperm Analysis) with configurations adapted to species. The results will be subjected at one-way ANOVA at 5% of significance, in case of differences, the Tukey´s test will be applied.
News published in Agência FAPESP Newsletter about the scholarship: