RESUMO
Fingerlings of Labeo rohita subjected to sublethal unionized ammonia (0.132mg/l) for 30 days exhibited significant changes. Increase in haemoglobin, haematocrit, plasma cortisol, plasma glucose, plasma cholesterol and plasma lactic acid levels whereas, decrease in plasma chloride, liver and muscle glycogen, hepatosomatic index and DNA/RNA ratio of muscles with stable plasma protein was observed. Metabolic recovery was not observed within 30 days of exposure.
Assuntos
Amônia/toxicidade , Animais , Glicemia , Proteínas Sanguíneas/metabolismo , Cloretos/sangue , Colesterol/sangue , Cyprinidae/fisiologia , DNA/sangue , Metabolismo Energético/efeitos dos fármacos , Glicogênio/metabolismo , Hematócrito , Hemoglobinas/metabolismo , Hidrocortisona/sangue , Ácido Láctico/sangue , Fígado/metabolismo , Músculos/metabolismo , RNA/sangue , Fatores de TempoRESUMO
Investigation was conducted for 12 months in two water bodies, S1 with optimum water quality and S2 receiving sewage water. The water quality parameters were assessed in relation to the impact on the stress sensitive physiological parameters of fish Labeo rohita. While optimum levels of transparency, dissolved oxygen, unionised ammonia, alkalinity and hardness in S1 reflected in minimum variation of the physiological parameters of L. rohita but suboptimal levels of DO (nil-18.0 mg/l) and CO2 (nil-16.0 mg/l) observed diurnally and unionised ammonia (0.11-0.42 mg/l) found throughout the experimental period, resulted in significant variation in plasma cortisol (90.0-377.0 ng/ml), cholesterol (89.6-285.0 mg/dl) and condition factor (0.7-1.3) in L. rohita. The results are of significance for fish aquatic habitat management.
Assuntos
Amônia/análise , Animais , Aquicultura/métodos , Análise Química do Sangue/veterinária , Constituição Corporal/efeitos dos fármacos , Dióxido de Carbono/análise , Colesterol/sangue , Cyprinidae , Doenças dos Peixes/induzido quimicamente , Água Doce/química , Hidrocortisona/sangue , Índia , Oxigênio/análise , Estresse Fisiológico/induzido quimicamente , Temperatura , Poluentes Químicos da Água/toxicidadeRESUMO
Juveniles of L. rohita were exposed to sublethal levels of nitrite (0.02, 0.1 and 0.4 mg/l) for 2, 24, 48 and 96 hr. The time of exposure at individual concentrations of nitrite did not show any significant difference in haemoglobin, cortisol, chloride and lactic acid. Haematocrit showed significant reduction with increasing concentration of nitrite irrespective of duration of exposure. Fishes exposed to 0.4 mg/l nitrite showed significantly high levels of glucose beyond 2 hr. The mean erythrocytic fragility of fishes exposed to the 3 concentrations of nitrite for 3 exposure periods showed significant higher sensitivity to osmotic stress. The results suggest decrease in haematocrit and cell wall strength of erythrocytes creating stress to fish.
Assuntos
Análise de Variância , Animais , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Peixes/sangue , Hematócrito , Nitritos/toxicidadeRESUMO
Juveniles of fish L. rohita and R. rita subjected to a rapid (5 min) sublethal temperature increase from 28 to 35 degrees C showed significant increase in cortisol and decrease in interrenal ascorbic acid. Hypercholesterolemia, hyperglycemia and hyperlactemia were also evident accompanied by increased blood haemoglobin and haematocrit and stable protein levels. Compensatory responses were initiated within 72 hr in both the fishes. R. rita recovered more quickly indicating it to be more resistant to the heat stress than L. rohita. Hence fishes subjected to sublethal temperature stress should be given a metabolic recovery period of 72 hr prior to further stress being applied.