Fish disease outbreaks on Volta Lake tied to farm management lapses-CANR study

A study led by Doris Y. Baah of the Department of Fisheries and Watershed Management at the College of Agriculture and Natural Resources, KNUST has identified disease outbreaks as a major challenge to tilapia production on the Volta Lake.

The research examined how farm management practices, as well as farmers’ knowledge and perceptions, influence disease occurrence and fish mortality.

The study surveyed 56 fish farms across five districts along the lake and found that all had experienced disease outbreaks, with mortality rates ranging from 10% to 80% of stocked fish.

They identified infectious pathogens, particularly Streptococcus agalactiae and Infectious Spleen and Kidney Necrosis Virus (ISKNV), as the leading causes of disease outbreaks.

The researchers also found that poor water quality, high stocking densities and inadequate biosecurity measures contributed to disease occurrence.

Affected fish commonly exhibited symptoms such as bulging eyes, swollen abdomens and skin lesions, which are often associated with bacterial and viral infections.

Despite the severity of the outbreaks, most farmers relied on visual observations and consultations with fellow farmers to diagnose diseases, with limited use of laboratory testing.

The study further revealed inconsistencies in key management practices, including fingerling sourcing, fish grading, water quality monitoring and biosecurity protocols.

The researchers concluded that addressing disease outbreaks on Volta Lake requires a coordinated effort involving farmers, veterinary officers, researchers and regulatory agencies.

They recommended strengthening extension services, increasing farmer training and establishing well-equipped diagnostic facilities around the lake to improve disease detection and response.

The study was published in the Frontiers in Aquaculture Disease and Health Management.