Gonçalves Junior Lucas Pedro, Mattioli Cristiano Campos, Martins Edenilce de Fátima Ferreira, Silva Walisson de Souza E, Ciolete Tarso Natividade, Vasconcellos Angélica da Silva, Luz Ronald Kennedy
Laboratório de Aquacultura, Departamento de Zootecnia, Escola de Veterinária, Universidade Federal de Minas Gerais - UFMG, Av. Antônio Carlos, 6627, CEP 31270-901 Belo Horizonte, MG, Brazil.
Laboratório de Comportamento e Bem-estar Animal, Programa de Pós-graduação em Biologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, Rua Dom José Gaspar, 500, Prédio 41, Belo Horizonte, Brazil.
J Therm Biol. 2019 Feb;80:133-140. doi: 10.1016/j.jtherbio.2019.01.008. Epub 2019 Jan 8.
The present study evaluates whether increased water temperature induces reproduction by Lophiosilurus alexandri under controlled conditions, and investigates the effects of this procedure on sexual steroids, hematological profile and behavior. A 44-week experiment was performed with four wild males and 12 wild females that had been acclimatized to captive conditions. Water temperature was maintained at 24.4 ± 1.0 °C for weeks 1-22, and then at 29.0 ± 1.1 °C for weeks 22-44. Spawn weight, number of eggs/spawn and hatching rate were satisfactory and ranged 27.5-127.5 g, 1209-5183 and 83-89%, respectively. Hematocrit, leukocytes and glucose were not influenced by increased water temperature, while higher values for erythrocytes were observed for both sexes. The lowest value for plasma protein was for females maintained at 29.0 °C, while the lowest value for testosterone was obtained at the end of the study period at a temperature in 29.0 °C. Serum values of 17β-estradiol were higher in females than in males, however, there was no evidence of variation as a function of experimental temperature or interaction with sex. The reproductive behavior of L. alexandri in captivity is described for the first time. The present study demonstrates that adult individuals are able to maintain a stable hematological profile during an increase in mean water temperature from 24.4 °C to 29.0 °C, even during the reproductive period, and still produce good quality larvae. Nonetheless, whether spawning was associated with increased 17β-estradiol levels could not be determined.
本研究评估了在可控条件下，水温升高是否会促使亚历山大低眼无齿脂鲤繁殖，并研究了这一过程对性类固醇、血液学指标和行为的影响。对4只野生雄性和12只野生雌性进行了为期44周的实验，这些鱼已适应圈养条件。第1 - 22周水温维持在24.4±1.0°C，然后在第22 - 44周维持在29.0±1.1°C。产卵重量、每次产卵的卵数和孵化率均令人满意，分别为27.5 - 127.5克、1209 - 5183枚和83 - 89%。血细胞比容、白细胞和葡萄糖不受水温升高的影响，而两性的红细胞值均较高。血浆蛋白的最低值出现在维持在29.0°C的雌性中，而睾酮的最低值出现在研究期结束时29.0°C的水温条件下。雌性的血清17β - 雌二醇值高于雄性，然而，没有证据表明其随实验温度变化或与性别存在交互作用。首次描述了亚历山大低眼无齿脂鲤在圈养条件下的繁殖行为。本研究表明，成年个体在平均水温从24.4°C升高到29.0°C的过程中，即使在繁殖期也能够保持稳定血液学指标，并且仍能产出高质量的幼体。尽管如此，产卵是否与17β - 雌二醇水平升高有关仍无法确定。
