Ecological parameters of the endohelminths in relation to size and sex of Prochilodus argenteus (Actinopterygii: Prochilodontidae) from the Upper São Francisco River, Minas Gerais, Brazil

• Main Authors: Cassandra M. Monteiro, Michelle D. Santos, Nágila A. Zuchi, Marilia C. Brasil-Sato
• Format: Article
• Language: English
• Published: Pensoft Publishers 2009-12-01
• Series: Zoologia (Curitiba)
• Subjects: Helminths; Neoechinorhynchus; Saccocoelioides; Spinitectus; Valipora
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702009000400021
• ISSN: 1984-4670; 1984-4689

This research aimed to investigate the ecological indexes of the helminths of the digestive system and coelom of Prochilodus argenteus Spix & Agassiz, 1829. A total of 150 specimens (53 males and 97 females) taken from the upper reaches of the São Francisco River in the municipality of Três Marias (18º12'32"S, 45º15'41"W), State of Minas Gerais, Brazil, were examined. The specimens were collected in July, 2003 and January, 2004. Ninety-eight fish (65.3%) were infected by at least one species of helminth. Five helminth species were found: one digenean, Saccocoelioides nanii Szidat, 1954; two Eucestoda, Valipora sp., and one undetermined metacestode; one nematode, Spinitectus asperus Travassos, Artigas & Pereira, 1928; and one acanthocephalan, Neoechinorhynchus prochilodorum Nickol & Thatcher, 1971. The sex of the host did not influence parasite indexes. The total length of the hosts influenced the abundance of S. nanii (r s = -0.21, p = 0.01) and the prevalence of the metacestode (r = -0.91, p = 0.01). Saccocoelioides nanii was the dominant species in the parasite fauna of P. argenteus. Saccocoelioides nanii, Valipora sp., S. asperus and N. prochilodorum are reported here for the first time in P. argenteus and their known distribution is expanded to the São Francisco River.