The present experiment was carried out to evaluate the growth and reproductive parameters of Rhamdia quelen females fed with pelleted ration containing different levels of digestible energy, and to evaluate the vigor of their offspring. The breeders were placed in tanks under conditions of photoperiod and natural temperature. The fishes were fed for 255 days with isoproteic rations pelleted containing 35% of crude protein (CP) and five levels of the digestible energy (DE) (2700, 2950, 3200, 3450, 3700 kcal kg-1). The fishes were distributed in a randomized experimental design compounded by five treatments and three repetitions. A 16-m² tank containing six females and three males was considered as one experimental unit. The weight and weight gain was evaluated. During the reproductive season the females were induced to breeding by hormonal manipulation and were evaluated the percentage of spawning females, the total fecundity, relative fecundity (number of oocytes per gram of spawning females), the fertilization ratio, the time to hatching and the vigor of larvae. The growth and reproductive parameters were not influenced (P > 0.05) by the increasing levels of digestible energy of the rations. The feeding of R. quelen females in breeding fit can be carried out with 2700 kcal kg-1 pelletized ration based on vegetal ingredients, without damage to reproductive performance.

El presente estudio se efectuó para evaluar el crecimiento y reproducción de hembras de bagre (Rhamdia quelen) alimentadas con dietas con diferente contenido de energía, elaboradas con ingredientes vegetales. Además, se evaluó el vigor de las crías. Los reproductores se colocaron en estanques en condiciones de fotoperiodo y temperatura ambiente. Los peces fueron alimentados durante 255 días con raciones isoproteicas que contenían 35% de proteína cruda (PC) y 2700, 2950, 3200, 3450 y 3700 kcal de energía digestible (ED) kg-1. Los peces se distribuyeron en un diseño completamente al azar con cinco tratamientos y tres repeticiones. Para el experimento se emplearon estanques de ~16 m² con seis hembras y tres machos. Se evaluó el peso medio final y la ganancia media de peso. Durante el período reproductivo se evaluó el porcentaje de hembras que desovan, número total de ovocitos, número de ovocitos por gramo en hembras reproductoras, tasa de fertilización, tiempo necesario para que la eclosión de los huevos y tiempo de supervivencia de las larvas. El crecimiento y los parámetros reproductivos no fueron afectados (P > 0,05) por el aumento de los niveles de energía de las raciones. Se concluye que para obtener mejor reproducción de bagre (R. quelen) se recomienda emplear raciones peletizadas de 2700 kcal kg-1.

This study was carried out to evaluate the influence of different levels of digestible energy and digestible protein in diets of Nile tilapia (Oreochromis niloticus) broodstock on offspring growth during sex reversal stage. A total of 2,700 post-larvae (8.2±0.001 mg) derived from breeders fed nine diets with distinct levels of digestible protein (28, 34 and 40% DP) and digestible energy (2,800; 3,400; and 4,000 kcal DE.kg-1) were stored in twenty-seven 70 L tanks. After 30 days of growth, their average final weight (AFW, g), average weight gain (AWG, g), final standard length (SL, cm), condition factor (CF), specific growth rate (SGR, %/day), stock uniformity (UNI, %), survival (SUR, %) and sex reversal rate (SRR, %) were measured. Although female nutrition is thought to influence the performance or quality of progeny during early life stages, no influence of diets supplied to broodstock was detected on any parameter. Nonetheless, the offspring presented commercially satisfactory growth rates. Thus, diets containing 28% of digestible protein and 2,800 kcal of digestible energy.kg of diet-1 can be used to feed Nile tilapia broodstock without jeopardizing offspring performance during the sex reversal phase.

The objective of this study was to evaluate the effects of water volume and water temperature on the sperm motility duration and the number of spermatozoa, and the water volume on the fertilization rates of oocytes of Rhinelepis aspera. Experiments were carried out to evaluate the effect of semen dilutions (1.74×10-5, 1.74×10-4, 1.74×10-3, 1.74×10-2, 1.74×10-1 and 1.00 mL of sperm.mL-1 of water) and water temperature (5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 ºC) on spermatozoa motility duration. In addition, the effects of insemination dose (7×10³, 7×10(4), 7×10(5), 7×10(6) and 7×10(7) spermatozoa.oocyte-1) and water volume (1.0, 30.0, 60.0, 90.0 and 120.0 mL water.2.0 mL-1 oocytes) on the artificial fertilization rates of oocytes were evaluated. The longest sperm motility duration were observed for the semen dilution of 1.74×10-5 mL semen.mL-1 water and in water at 5 ºC. The highest fertilization rates were obtained for insemination doses between 7.00×10³ and 1.23×10(7) spermatozoa. oocyte-1 and water volume of 28.11 mL water.2.0 mL-1 oocytes.

Um experimento foi realizado com o objetivo de estimar a concentração espermática das espécies dourado (Salminus brasiliensis), curimba (Prochilodus lineatus), jundiá (Rhamdia quelen), cascudo-preto (Rhinelepis aspera) e tilápia-do-nilo (Oreochromis niloticus) pelo método de espermatócrito. Utilizaram-se 19, 58, 51, 43 e 85 reprodutores de dourado, curimba, jundiá, cascudo-preto e tilápia-do-nilo, respectivamente. Com exceção da tilápia-do-nilo, os reprodutores foram submetidos ao processo de indução hormonal e posteriormente submetidos a coleta de sêmen. Foram comparadas as técnicas de mensuração da concentração espermática do sêmen por contagem em câmara hematimétrica de Neubauer e por espermatócrito. Os resultados obtidos foram submetidos à análise de regressão a 5% de probabilidade. As concentrações espermáticas mensuradas por ambas as técnicas apresentaram relação linear, para curimbas, jundiás e tilápias-do-nilo, com equações y = 6,6624 × 10(9) + 3,68553 × 10(8)x; y = 2,153 × 10(9) + 4,426 × 10(8)x e y = -9,0897 × 10(8) + 6,0167 × 10(8), respectivamente. O método de espermatócrito pode ser utilizado para estimar a concentração espermática do sêmen de curimbas, jundiás e tilápias-do-nilo.

The objective of this experiment was estimate sperm concentration of "dourado" (Salminus brasiliensis), "curimba" (Prochilodus lineatus), "jundiá" (Rhamdia quelen), "cascudo-preto" (Rhinelepis aspera) and Nile tilapia (Oreochromis niloticus) by the method of spermatocrit. It was used 19, 58, 51, 43 and 85 brood fish of "dourado", "curimba", "jundia", "cascudo-preto" and Nile tilapia, respectively. Except for the Nile tilapia, the fishes were subjected to the hormonal induction process and then submitted to the semen collection. The measurement techniques of the sperm concentration by sperm count in Neubauer chamber (CSPZ) and by spermatocrit (ESPMT) were compared. The results were submitted to the regression analysis at 5% of probability. It was observed that the variables CSPZ and ESPMT presented linear relationship to the "curimba", "jundia" and Nile tilapia with equations y = 6.6624 × 10(9) + 368553 × 10(8)x; y = 2.153 × 10(9) + 4.426 × 10(8)x and y = -9.0897 × 10(8) + 6.0167 × 10(8), respectively. The method of spermatocrit can be used to estimate the sperm concentration of "curimba", "jundiá" and Nile tilapia.