Haematozoa from resident and anadromous fishes of the central Columbia River: a survey

Abstract

Fish were surveyed for haematozoa from the central Columbia River, state of Washington, U.S.A., from 1968 to 1978. The 840 individuals examined represented 12 families and 34 species. Most infections occurred in sucker (Catostomidae) and sculpin (Cottidae). Nine species of fish were parasitized by one or two species of haematozoa. Intensities of all detected parasitemias were low, indicating no symptomatic damage to infected hosts.Trypanoplasma salmositica (Katz 1951) was recorded for the first time in white sturgeon (Acipenser transmontanus), largescale sucker (Catostomus macrocheilus), bridgelip sucker (C. columbianus), northern squawfish (Ptychocheilus oregonensis), and sculpin of the Cottus confusus/bairdi complex; it was also found again in prickly (C. asper) and piute (C. beldingi) sculpin. Haemogregarina catostomi Becker 1962 occurred in about 23% each of largescale and bridgelip sucker. Other haematozoa encountered were a haemogregarine in 1 of 23 steelhead (Salmo gairdneri), a haemogregarine in 3 of 92 sculpin (Cottus spp.), and a dactylosome in 1 of 10 American shad (Alosa sapidissima).The sequence of Haemogregarina catostomi occurrence in erythrocytes was the following: young gametocytes in the fall, mature gametocytes in winter, degenerative gametocytes in spring, and absence of infection in summer. The piscicolid leeches Myzobdella lugubris Leidy and Piscicola salmositica Meyer might transmit haematozoa among fish in the survey area.