Aggregation of congeneric parasites (Monogenea: Dactylogyrus) among gill microhabitats within one host species (Rutilus rutilus L.)

Abstract

Parasite aggregation within the gill arches of 1 host species (Rutilus rutilus L.) was studied in the case of 9 congeneric monogeneans belonging to the genus Dactylogyrus. Both intra- and interspecific aggregation were followed by considering gill arches as independent patches. Parasite species were found to be aggregated both intra- and interspecifically. We showed that the intensity of parasite infection was positively related to intraspecific aggregation only for the more abundant species. No relationship was found between intensity of parasite infection and niche size when correcting for total parasite intensity. This may suggest that when parasite intensities are low, intraspecific competition may not have a strong effect on parasites. Conversely, when looking at the evolution of niche size and intraspecific aggregation for each species separately, intraspecific aggregation decreased for the most abundant species (D. crucifer) suggesting that this species is more competitive than others when total parasite intensity increases. When considering interspecific aggregation, Dactylogyrus species were found to be positively and negatively aggregated. Following the prediction of morphological and ecological similarity for congeneric species, Dactylogyrus species similar in morphometry of attachment parts tend to be more positively aggregated among their gill microhabitats than Dactylogyrus species with morphometric differences in attachment parts.

Linking species abundance distributions and body size in monogenean communities

“…These figures are not unusual, and they actually match data from a range of other studies of monogenean assemblages on fish hosts (e.g. Geets et al 1997;Gutiérrez and Martorelli 1999;Gutiérrez 2001;Simkova et al 2001;Bagge et al 2004;González and Oliva 2006) and data from communities of gastrointestinal helminths in vertebrate hosts (see Fig. 9.10 in Poulin 2007).…”

Distribution of gill Monogenean parasites from Oreochromis niloticus (Linn, 1758) in man-made Lake Ayam I, Cte dIvoire

“…Blahoua et al (2009) also observed that C. acerbus, C. halli and Scutogyrus minus appeared to be more prevalent and more abundant in long rainy season. Our results can be explained by water temperature which is assumed to be an important factor in controlling the occurrence of Monogeneans Simkova et al, 2001). In fact, higher water temperature must have been harmful on the adult worms (Bilong and Tombi, 2005).…”

Effects of small weirs on fish parasite communities

“…As a consequence, the interspecific interaction between parasites remains a rare phenomenon (Cornell 1993;Gotelli and Rohde 2002). Indeed, the parasite communities observed in the Viaur River have low levels of species richness and relative abundances compared to other European rivers (Šimková et al 2001;Kadlec et al 2003), which may be related to the high level of eutrophication of the Viaur River (Guilmet 1997;Sidall et al 1997).…”