Barbus comizo infestation by Lernaea cyprinacea (Crustacea: Copepoda) in the Guadiana River, southwestern Spain
Summary
The purposes of this study were to collect baseline data on parasitology of a native species and to determine if parasite infestations by Lernaea cyprinacea were related to size, month and sex. An infestation of L. cyprinacea was monitored on Barbus comizo (n = 307) from March to October 2004 in the River Guadiana, south-western Iberian Peninsula; over 55.7% of the examined B. comizo were infested. The number of female parasites per fish ranged from 1 to 8. There were significant differences in prevalence, abundance, and intensity among months. Prevalence was highest in August, while abundance (5.16) and intensity (5.32) were highest in September. Infestation levels were significantly related to fish size (rs = 0.947, n = 171, P < 0.05) and condition factor (rs = −0.199, n = 169, P < 0.05). Haematocrit values were significantly lower in infected fish (Mann–Whitney U = 21, P < 0.05). The level of infestation was independent of sex (χ2 = 0.87, P < 0.05). The dorsal and ventral areas of the fish were the most heavily parasitized.