ADAPTATIONS OF THE PIAVA (Leporinus obtusidens) JUVENILE EXPOSED TO HYPOXIA

作者：Jimenez Jhon Edison^*; Zaniboni Filho Evoy

来源：Boletim do Instituto de Pesca, 2013, 39(4): 439-444.

• Dissolved oxygen
• hematocrit
• erythrocytes
• gills
• blood

The piava (Leporinus obtusidens) is a migratory freshwater fish. There is relatively little information on the hematological and morphological adaptations of tropical freshwater fish when subjected to chronic and sublethal concentrations of dissolved oxygen (DO). The aim of this study was to verify the existence of adaptations of the gills and blood in juvenile piava exposed to different concentrations of DO. The juveniles used in this experiment were cultured for 70 days at different DO concentrations (1.74 +/- 0.04, 3.54 +/- 0.06, 5.34 +/- 0.05 and 7.34 +/- 0.02 mg L-1) and kept at mean water temperature of 26.4 degrees C. Individuals subjected to conditions of severe hypoxia (1.74 mg L-1 DO) showed a significant increase in the number of erythrocytes (P<0.05) and a decrease in erythrocyte corpuscular volume (P<0.05), but no changes were observed in gill lamellae. This study concludes that L. obtusidens juveniles undergo hematological change when exposed to conditions of severe hypoxia.

• 出版日期2013