Silver Salmon (Oncorhynchus kisutch) with Cysts

Observation: Silver salmon, caught 10 miles up the Twin Hills river, had small white patches in the flesh. They looked like small white eggs but were more like patches in the flesh of the fish. None of the other fish caught that day had these patches in the meat. This was the first time that the observer had seen these patches.

This post was created by Erica Mitchell on behalf of Twin Hills resident Micky Sharp.

Jayde Ferguson of the Fish Pathology Lab at Alaska Department of Fish and Game:

These do appear to be parasite cysts. Although there are a few different parasites that have this presentation, they are likely Henneguya based on the photograph and fish species involved. More information on this parasite can be found in the Fish Disease Booklet.

Comments from LEO Editors:

About 100 miles to the ENE of Twin Hills, AK, up the Nushagak River lies the community of New Stoyahok with a similar observation posted on September 24, 2014. A resident caught coho salmon with bumps between the skin and the flesh that resembles this observation. This observation was forwarded to the Alaska Department of Fish and Game Pathology Lab.

Resources:

Alaska Department of Fish and Game – Common Diseases of Wild and Cultured Fishes in Alaska, a good reference for learning about illness in salmon. "Information contained within this booklet is published from the laboratory records of the Alaska Department of Fish and Game, Fish Pathology Section that has regulatory oversight of finfish heal in the State of Alaska." Meyers, T., et al. July 2008.

Sea Grant Delaware – Parasites, describes "food safety issues associated with naturally occurring parasites that could be associated with certain types of seafood products." Seafood Health Facts: Making Smart Choices - Balancing the Benefits and Risks of Seafood Consumption - Resources for Healthcare Providers and Consumers