Preferencia termal de postlarvas del camarón de río Cryphiops caementarius previamente aclimatados a diferentes temperaturas

Temperature is one of the main environmental parameters that affects growth, reproduction and migration of ectothermic animals. The aim of this research was to determine the thermal preference of the postlarvae of the river shrimp Cryphiops caementarius, previously acclimatized to different temperatures. The postlarvae were collected from the Mala River and acclimatized for 60 days in the laboratory at 19.4 ± 0.6 ºC (control), 22, 24, 26, 28 and 30 ºC. The experimental thermal gradient system (10 ºC to 33 ºC) consisted of a PVC gutter (3 m long and 10 cm deep), with 18 compartments. Thermoregulators (100 W) or frozen hydrogel bags were placed on opposite ends of the gutter. The thermal preference was determined with the acute method and the tests were carried out between 08:00 and 14:00 h. The postlarvae acclimatized to 19 ºC and 22 ºC were moved to compartments with higher temperatures than their acclimatization temperature. The postlarvae acclimatized to 28 ºC and 30 ºC were moved to compartments with lower temperatures than their acclimatization temperature. The postlarvae acclimatized to 24 ºC and 26 ºC were moved to compartments with similar acclimatization temperature. The acclimatization temperature had no significant effect (P>0.05) on the thermal preference (23.9 ºC to 24.7 ºC) of the postlarvae and the final thermal preference was 24.5 ºC. We propose, that this thermal preference is taken into account for the culturing this species.