Oksidatif Stres

Abstract

The reactive oxygen species formed as a result of oxidative reactions bind to cellular structures such as proteins, lipids, carbohydrates and DNA, causing structural damage. Therefore, this oxidative damage caused by reactive oxygen derivatives is called oxidative stress. Environmental conditions known to cause oxidative stress in aquatic organisms are generally; temperature, oxygen level, salinity, seasonal rhythm changes, transition metal ions, pesticides and petroleum derivatives. The formation of free radicals in fish starts and increases due to heavy metals, pesticides and environmental pollution. In addition, important sources of oxidative stress encountered in addition to known environmental factors in growing conditions are hunger and disease states. The situation in fisheries caused by the diseases of fish is a source of stress in itself. In this case, the diagnosis and treatment process should be initiated. Fish exposed to hunger conditions; gives many physiological symptoms. Hormonal and enzyme changes are the leading ones. Especially because hunger factor is directly related to energy metabolism, it causes some negative changes in the liver where energy activities are intense. It is important to remember that it is important in feeds used in aquaculture. Not only in fasting conditions, but also in fish fed with poorly adjusted feeds, stress effects are seen. Oxidative stress is usually seen in fish fed with dense fatty feeds due to lipid octidation. In addition, diets prepared differently from the feeding habits of fish can create these negative situations. For example, carnivore nutritional properties of fish containing intense carbohydrate feed, such as use. Along with feeding and disease factors, environmental factors should be considered in aquaculture establishments. The water temperature, salinity, pH, oxygen and the levels of the macro and micro elements should be determined well. Therefore, oxidative stress is one of the most important issues to be considered in aquaculture in recent years. In this review, it is aimed to give detailed information about the effects of oxygen on vital functions in fishes, reactive oxygen species formed as a result of oxidative reactions and especially the most important oxidative stress factors encountered in fish farming