In order to evaluate the zootechnical parameters for red-tailed tarpon Brycon cephalus fingerlings, in a region other than Amazonia, the evaluation of growth parameters in temperate waters was carried out for 60 days in the port of Ilo, Department of Moquegua. 84 fingerlings were used in 70 liters of water and two biometrics were performed, fluctuating in size from 3.5 cm to 9 cm at the end of the trial. Fingerlings were fed commercial trout feed of 45% protein, 8% fat and 25% carbohydrate, a feeding rate of 4.5% of biomass, distributed 3 times per day. The results reported as an average water temperature of 20.6°C, survival rate of 2.4%, growth determined by y=0.0155 X 2.8284 and a coefficient of determination of R²=0.975, average condition factor (K): 0.04393±0.0126 SD, Relative Growth Rate (TCR) of 9.5%, Specific Growth Rate (TCE) of 3.9% and Apparent Feed Conversion (CAA) of 1.4. With which it is observed that the parameters evaluated in the coastal zone of southern Peru are close to the native cultivation conditions.

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The present research work was developed, with the purpose of evaluating the effect of two cryopreservation times and two cryoprotectants, on the viability of Colossoma macropomum semen, "gamitana". and it was developed in the facilities of the “Fernando Alcántara Bocanegra” Research Center, of the Peruvian Amazon Research Institute-IIAP. A sex ratio of 1:2 (Female: Male) was used, collecting semen in a 0.4 M solution of sucrose. For the cryopreservation process, the semen was subjected to two freezing times (6 minutes and 9 minutes) and two levels of cryoprotectants (Level 1:10% DMSO at 0.1 M and level 2:43% dextrose at 0.3 M). It was fertilized with 25 μL of thawed semen, using a factorial design of 22, which were subjected to an ANOVA, at 95% confidence. Fresh semen evaluation shows that motility time presented a significant difference p=0.021. However, in the post-thaw semen evaluation, motility time and motility percentage did not present a significant difference (p > 0.05) for each breeder, but a reduction in the average times was evidenced, compared to fresh semen. For fertilization percentage, only freezing time presented a significant difference (p=0.000001), for male 1 and male 2 no significant differences were found between treatments. For hatching percentage, according to freezing time and percentage of cryoprotectant, for male 1, no significant differences were found p > 0.05 and for male 2, significant differences were found (p=0.043), for cryoprotectant percentage. In relation to larvae malformation percentage, freezing time and type of cryoprotectant, did not show significant differences (p > 0.05), for breeders, however, they were higher in relation to fresh semen treatment. Therefore, it is evident that there would be an unknown factor of male, which did not allow replicating the values obtained, which is manifested in the synergy of variables studied, for this species.