Thermal stress altered growth performance and metabolism and induced anaemia and liver disorder in Labeo rohita

Abstract

Sudden fish deaths occurred during summer peaks in India and expected to be more in future. This study was conducted to explain the biochemical responses of Labeo rohita under extreme thermal condition (treated: 37–38°C against controlled: 28–30°C). Exposure of 14 days resulted in 30% of fish mortality. Glucose concentration was maintained in serum for both treated and controlled groups. However, triglycerides, protein, globulin, calcium, cholesterol and haemoglobin were declined and enzymes (glutamate‐pyruvate transaminase, GPT and glutamate‐oxalate transaminase, GOT) were elevated in serum in the treated group. Indicators of overall metabolism (biomolecules: glucose, triglycerides, protein, cholesterol; enzymes: GPT, GOT; and RNA: DNA) were diminished in liver, whereas these were less affected in muscle. Higher GPT, GOT and lower albumin in serum confirmed disturbance in hepatic panel. Simultaneously compromised growth (lower SGR, DNA content in liver) was observed in treated fish due to impaired metabolism. Extreme thermal stress induced by such catastrophic warmer water exposure caused liver problems and anaemia which ultimately caused fish death.

A Multi-Biomarker Approach in European Sea Bass Exposed to Dynamic Temperature Changes under Dietary Supplementation with Origanum vulgare Essential Oil

“…Serum glucose level is another index of thermal stress, and supply of glucose in bloodstream allows to cope with high metabolic needs in stressed organisms [45,46]. In the present report, fish fed on CD showed an increase of serum glucose content upon exposure to 15 and 18 • C. As primary response to cold stress, the stimulation of glycogenolysis by catecholamines promotes the breakdown of hepatic glycogen and the release of glucose into the blood [47,48].…”

“…Serum glucose level is another index of thermal stress, and supply of glucose in bloodstream allows to cope with high metabolic needs in stressed organisms [ 45 , 46 ]. In the present report, fish fed on CD showed an increase of serum glucose content upon exposure to 15 and 18 °C.…”

Multi-Omics Analysis Provides Novel Insight into Immuno-Physiological Pathways and Development of Thermal Resistance in Rainbow Trout Exposed to Acute Thermal Stress

“…Global warming is becoming an ever more serious problem, and the effects of global warming are more severe for ectotherms, including fish, that live in an aquatic environment than animals that live on land [3,5]. Extreme thermal stress is a major abiotic factor that can trigger mortality in teleost fish [6][7][8]. For example, 30% of rahu (Labeo rohita) died within two weeks when water temperature was increased by 8.5 • C at a rate of 3 • C day −1 [7].…”

“…Extreme thermal stress is a major abiotic factor that can trigger mortality in teleost fish [6][7][8]. For example, 30% of rahu (Labeo rohita) died within two weeks when water temperature was increased by 8.5 • C at a rate of 3 • C day −1 [7]. Also, all sea bream (Sparus aurata) were killed within one week when water temperature was increased 12 • C at a rate of 6 • C day −1 [8].…”

Responses of aquaculture fish to climate change‐induced extreme temperatures: A review

“…In fish and other animals, during thermal stress, functional tissues and organ damage release some specific cellular enzymes into the bloodstream and can be used as stress indicators (Krajnovic‐Ozretic & Ozretic, 1987; Roychowdhury et al, 2020). Significantly higher accumulation of glutamic‐pyruvate transaminase (GPT), glutamic oxaloacetic transaminase (GOT), lactic acid dehydrogenase (LDH), gamma‐glutamyl‐transaminase (γGGT) in European seabass, D. labrax exposed at cold (8°C) temperature (Islam, Kunzmann, Henjes, & Slater, 2021) and high (>32°C) temperature (Islam, Slater, & Kunzmann, 2020) indicate reduced liver function because of damaged hepatocytes and other cellular injuries.…”