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Email the author (Login required) Effect of temperature on survival of embryos of puye Galaxias maculatus (Jenyns, 1842)
DOI: https://doi.org/10.3856/vol41-issue5-fulltext-4
Abstract
We evaluated the effect of six constant temperatures on embryonic survival, embryonic period and hatching period of Galaxias maculatus from 7 to 22°C under laboratory conditions. The results of embryo survival were: 90.6 ± 2.0, 88.7 ± 8.6, 87.7 ± 0.7, 89.7 ± 4.2, 70.0 ± 5.6 and 49.5 ± 7.4% at temperatures of 7, 10, 13, 16, 19 and 22ºC. Except for the temperature of 22°C, there were no significant differences between them (P < 0.05). These results characterize the embryo as eurythermic regardless of being a subantarctic waters species. Regarding the embryonic period (ʈʜ50%), the results were 40.8 ± 0.6, 27.0 ± 0.0, 17.3 ± 0.6, 16.3 ± 0.6 and 13.3 ± 0.6 days at temperatures of 7, 10, 13, 16 and 19°C respectively, with significant differences between them (P < 0.05) and in the case of the hatching period (ʈʜ50%), was 8.3 ± 0.6, 6.3 ± 1.5, 5.0 ± 0.0 and 6.3 ± 0.6, 5.0 ± 1.0 and 4.3 ± 0.6 days at temperatures of 7, 10, 13, 16, 19 and 22ºC respectively with significant differences between them (P < 0.05). These results suggest that the range of temperatures between 10 and 16°C is optimal for the incubation of G. maculatus eggs, since in that range high embryonic survival (>87.7%) combined with embryonic periods of less than 27 days and hatching periods less than 6.3 days were obtained. These results will optimize embryo survival and eventually rearing of the species for commercial purposes or restocking.
