Seminal quality in rainbow trout (Oncorhynchus mykiss Walbaum, 1792) with respect to weight

Document Type : Primary Research paper



In aquaculture farms, growth is an essential factor in assessing the yield of inputs, welfare of organisms and accelerating sexual maturity; the objective of the investigation was to determine seminal quality with respect to weight: one, two, three and four kilograms. Ninety-four males were anesthetized with clover essence at a concentration of 0.05 mL L-1 of water. The semen was extracted by light abdominal pressure in the operculum-caudal direction. The sperm concentration was determined with Neubauer chamber, viability with eosin-nigrosin, estimated in percentage and motility was evaluated by activating with water. The results indicate that increasing the weight increases the volume. In the one kilogram males the mean volume was 8.0 ± 3.9 mL, in those of two 11.1 ± 6.1 mL, in those of three 12.3 ± 8.3 mL and in those of four 29.2 ± 21.8 mL. On the other hand, the sperm concentration mL-1 showed an inverse tendency to the volume being the two kilograms males who showed the highest concentration 6.80 ± 0.55 x 109 spermatozoa mL-1; the highest percentage of viability 94.19 ± 1.42 % was obtained in males of two kilograms and the best motility with 86.00 ± 4.14 s in those of three kilograms. The variables presented differences (P ˂ 0.05) in relation to the weight. Considering the variables of the study, it is proposed to use two kilograms organisms to ensure fertilization, which will reduce operating costs.