Red mark syndrome (RMS) in farmed rainbow trout (Oncorhynchus mykiss): first report of outbreak in Peruvian Salmonid Aquaculture.

Red Mark Syndrome (RMS) is a skin disease affecting predominantly rainbow trout and is likely caused by a Midichloria-like organism. This condition primarily affects commercially-sized fish and can cause severe chronic dermatitis, panniculitis, and myositis, ultimately resulting in significant economic losses. RMS has been reported in at least three continents, but its presence has only been confirmed in Chile within South America. Nevertheless, it continues to pose a significant threat to the aquaculture of rainbow trout. In this context, we present the first documented outbreak of RMS in Peruvian Salmonid Aquaculture.