Skeletal Deformities in Cultured Striped Catfish Pangasianodon hypophthalmus (Sauvage, 1878) in the Mekong Delta, Vietnam

Skeletal deformities are a common issue that poses a challenge that hinders the production of cultured finfish worldwide. The present study aims to describe for the first time skeletal deformities in cultured striped catfish Pangasianodon hypophthalmus (Sauvage, 1878) from the Mekong Delta, Vietnam. A total of 68 striped catfish were collected from three nurseries in highly concentrated areas of Long An and Dong Thap provinces. These provinces are known for their numerous hatcheries and nursing farms of P. hypophthalmus in the country. The skeletal deformities recorded included saddleback syndrome, missing pectoral fins, lordosis and kyphosis, unilateral deformities of the opercular complex bones, branchiostegal ray and lower jaw deformities. Abnormalities in bone morphotypes between normal and deformed fish were analysed using X-ray scanning and double staining (alizarin red and alcian blue) methods. The morphological abnormalities, in general, can reduce the fillet yield of fish, thereby affecting their market value. Since P. hypophthalmus is the most important freshwater fish exported from the Mekong Delta, a regular monitoring program of skeletal deformities can contribute to identifying improved rearing protocols and enhance the product quality available in the markets.