Aquaculture animal health protection is a significant segment of the work of the Animal Health Sector. The Institute's employees cooperate with cyprinid and salmonid fish farms in the country and the region, as well as with fish feed producers and distributors. In addition to field work, the Institute performs diagnostics of important parasitic, bacterial and viral fish diseases.

Coldwater, or salmonid, fish farms in the country mainly raise California trout. Farming in flow-through facilities and cages dominates. The most common pathological conditions are parasitic diseases caused by flagellates and ciliates, as well as bacterial diseases caused by Yersinia ruckeri, Flavobacterium spp. and other pathogens.

In warm-water, cyprinid ponds, carp, grass carp and silver carp are mostly kept. Pathological conditions caused by changes in water quality and parasitic diseases dominate. Myxosporidiosis, dactylogirosis, tapeworm infections, and infections with unicellular parasites are common. It is also not uncommon for bacterial and fungal diseases to be diagnosed in such ponds.

Redmouth disease of California trout caused by Yersinia ruckeri

This disease is one of the most frequently diagnosed systemic diseases of California trout in our country. Its importance is reflected in the large direct losses it causes. Namely, yersiniosis mainly causes the death of larger juveniles or pre-consumable fish. It is characterized by dark pigmentation, bulging, and the presence of scabs on the edges of the mouth and at the bases of the fins. The anal opening is red. Bleeding is common in the internal organs. The spleen is enlarged, and the intestines are affected by a catarrhal or hemorrhagic inflammatory process.

Although the disease can be successfully treated with antibiotics, priority should be given to preventive measures, which include biosecurity measures and vaccination with inactivated vaccines.