Ammonia induced toxico‐physiological responses in fish and management interventions

Abstract

ntensification of aquaculture practices resulted in increased ammonia production inthe culture systems. Lack of proper management of the culture system will result inelevated ammonia, which adversely affects the culture species. Moreover, with theongoing global warming, fish metabolism and ammonia excretion are expected toincrease. This, coupled with the hypoxic condition, exacerbates the severity ofammonia toxicity. Ammonia toxicity can alter the growth and the biochemical, physi-ological and immunological responses of fish. Several factors such as pH, tempera-ture, salinity, dissolved oxygen, species and life stages of fish, physical activity,feeding and stress influence the toxicity of ammonia in fish. A proper understandingof these factors is a prerequisite for successful aquaculture. The physiologicalchanges caused by the elevated ammonia hinder homeostasis that eventuallyincreases their susceptibility to diseases. This review discusses ammonia toxicity infish, factors affecting the toxicity and various physiological, haematological, histologi-cal and immunological responses induced by the elevated ammonia. Furthermore, thereview summarizes various management and dietary interventions to mitigateammonia and ammonia induced stress in aquaculture.