Prevalencia e intensidad de helmintos parásitos del tracto digestivo de la trucha arcoiris Oncorhynchus mykiss nelsoni (Pisces: Salmonidae), de Baja California, México

Abstract

The prevalence and mean intensity of helminths in the digestive tract of San Pedro Mártir rainbow trout (Oncorhynchus mykiss nelsoni) were studied in Ihe Arroyo San Rafael. Baja California, México, by examining 175 especimens (44-208 mm standard length and 0-4 years old) during one year. The trematode Crepidostomum cooperi (fopkin 1934) (Allocreadiidae) was lhe most prevalent (prevalence = 81%) and numerous (mean intensity = 14.7) parasite, followed by the nematode Rhabdochona cascadilla Wigdor 1918 (Rhabdochonidae) (38% and 3.9. respectively). The mean intensity of C. cooperi increased with the length and age of the host, but it was similar between sexes. In addition, the mean intensity of R. Cl/,cascadilla was similar regarding the length, age and sex of the host.