It has been established that loss of fish are mainly due to infectious diseases occurring in fish aquaculture. One of main causes for mortality and economic loss is due to fungal infections in cultured fishes. The major fungal infection is Saprolegniasis, aquatic mycotic winter freshwater fish disease1, 2.
Saprolegniasis in fishes occurs due to stress factors such as; scraped skin, wounds or ulcers on the intact skin, sexual development, poor water quality and sudden fluctuation of water temperature. It is very difficult to treat this disease once it has taken hold3.
Numerous medications have been used to reduce the economic losses and decrease the number of fish anguish from such disease. Malachite green and potassium permanganate are considered the most effectual fish fungicides also formalin, the cheapest and effective alternative chemical has an acute impact on the aquatic environment. However, there is a critical requirement for new treatment against Saprolegniasis in fish.
Humic acid is used as chemotherapeutic in aquaculture. It is an eco-friendly compound and used for treating fish diseases, fungicide and bactericide effectively. Hydrogen peroxide, sodium hydroxide and humic acid have a law authoritarian priority categorization by US FDA to use as fungicide on fish4.
A new study on Saprolegniasis and its effect on cultured freshwater fish especially, tilapia Oreochromis niloticus with focus on its isolation and identification of the causative agent was conductd by Egyptian scientists. The most favorable preventive trials to control this disease in naturally infected O. niloticus using safe chemicals for both environment and human being were also evaluated5.
Researchers took 500 cultured Nile tilapia Oreochromis niloticus suffering from saprolegniasis, which is considered as the most important cause of mass mortalities in cultured freshwater fish in winter in Egypt.
The fishes were subjected to full clinical, postmortem, identification and hematological and biochemical examination. Humic acid, Hydrogen peroxide and sodium chloride was given for three successive treatments. From which it was observed that most effective, economic and safe for fish treatment was with Humic acid.
Your email address will not be published. Required fields are marked *
23 August, 2019