Malacological assessment and natural infestation of Biomphalaria straminea (Dunker, 1848) by Schistosoma mansoni (Sambon, 1907) and Chaetogaster limnaei (K. von Baer, 1827) in an urban eutrophic watershed

Abstract

The objective of this study was to perform a malacological assessment at the Ibirité reservoir watershed in the metropolitan region of Belo Horizonte (Minas Gerais) and to evaluate the natural infestation rate of Biomphalaria straminea (Gastropoda: Planorbidae)by Schistosoma mansoni (Platyhelminthes: Trematoda) and Chaetogaster limnaei (Oligochaeta: Naididae). The samples were collected from July to August 2002. The B. straminea individuals collected were kept in the laboratory; the natural infestation rate by S. mansoni and C. limnaei was assessed weekly. The malacological assessment identified fivemollusk species present in the Ibirité reservoir watershed: B. straminea, Physa marmorata, Lymnea sp., Melanoides tuberculatus,and Pomacea austrum. Laboratory observations showed that the B. straminea individuals were infected by C. limnaei rather than S. mansoni. Although there was no infection of B. straminea by S. mansoni,presence of B. straminea in itself merits close attention due to possible risk of human schistosomiasis by the local population.

Population dynamics of Chaetogaster limnaei (Oligochaeta: Naididae) in the field populations of freshwater snails and its implications as a potential regulator of trematode larvae community

“…However, several authors have reported higher prevalence ranging between 95 and 100% (Eggleton 1952;Gruffydd 1965;Buse 1971;Gale 1973;Conn et al 1996;Callisto et al 2005). Furthermore, some authors have reported intensities as high as 30 (Barbour 1977), 50 (Gruffydd 1965), or 70 parasites/host (Gamble and Fried 1976) at peak seasons.…”

“…An intimate association between the C. limnaei and many aquatic snail species has long been recognized as commensal or parasitic in several freshwater ecosystems (Andrade and Campos 1968;Gale 1973;Barbour 1977;Conn et al 1994;Callisto et al 2005). The presence of C. limnaei in snail vectors hinders and even stops infection by their trematode larvae.…”

Occurrence of Naididae (Annelida: Oligochaeta) from three gastropod species in irrigation fields in southeastern Brazil

“…and it was the only naidid species found in L. columella (Table 1). According to Buse (1972), C. limnaei inhabits a wide variety of gastropod snails and, in Brazil, it has previously been found in association with B. straminea ( Andrade & Campos 1968, Callisto et al 2005. This is the first report on the occurrence of D. (D.) righii in a living substratum, i.e., Biomphalaria sp.…”

Occurrence of Chaetogaster limnaei K. von Baer, 1927 (Oligochaeta, Naididae) associated with Gastropoda mollusks in horticultural channels in Southeastern Brazil

“…There are few records of the presence of C. limnaei associated with aquatic mollusks in Brazil (Ruiz, 1951;Andrade and Campos, 1968;Callisto et al, 2005). Thus, the present work aimed to evaluate the presence of this Naididae in association with four species of mollusks collected in irrigation channels of a horticultural garden in the city of Juiz de Fora, Minas Gerais.…”

“…The association between Chaetogaster limnaei K. von Baer, 1927 and various species of gastropod mollusks has been reported many times (Gruffydd, 1965a;Andrade and Campos, 1968;Buse, 1972Buse, , 1974Conn et al, 1995;Agbolade et al, 2007;Ibrahim, 2007;Fried et al, 2008), however the nature of this relationship has not yet been clearly defined (Callisto et al, 2005).…”