Fasciola hepatica: The Growth and Larval Productivity of Redial Generations in Galba truncatula Subjected to Miracidia Differing in Their Mammalian Origin

Abstract

Experimental infections of Galba truncatula with 4 isolates of Fasciola hepatica miracidia differing by their mammalian origin (cattle, nutrias, rabbits, or sheep) were carried out to determine if parasite origin had an effect on the number of free rediae, their growth, and their larval productivity in each redia category. The mammalian origin of miracidia had a significant influence on the numbers of free rediae (they were higher in cattle-group snails) and the lengths of rediae (they were lower in rabbit groups). The redia category had also a significant effect on body and pharyngeal measurements. In all groups, the majority of cercariae (55.8-63.2%) were produced by the daughter rediae (R2a rediae) originating from the first mother redia. Compared with the other groups, the mean number of cercariae at day 49 postexposure was twice as high in cattle groups. In contrast, the mean number of daughter rediae produced by each second-appearing mother redia or each R2a redia was higher in the nutria, rabbit, and sheep groups. The mammalian origin of F. hepatica miracidia had an effect on the number of live rediae, their length, and their redial and cercarial productivity.

Fasciola hepatica: An assessment on the vectorial capacity of Radix labiata and R. balthica commonly found in Belgium

“…The mortality rate for uninfected G. truncatula (7%) was lower than the 38% reported in a previous study (Vignoles et al, 2004). Here, mortality rates for R. labiata and R. balthica reached 4 and 38%, respectively.…”

“…The colony originated from a French population (46840 0 34.81 00 N and 1822 0 58.58 00 W), living in the commune of Migné, department of Indre. This population was used because past experimental infections proved that this population was highly susceptible to F. hepatica (Vignoles et al, 2001 …”

Fasciola hepatica demonstrates high levels of genetic diversity, a lack of population structure and high gene flow: possible implications for drug resistance

“…Thirdly, clonal expansion in the snail, combined with low levels of infection in the snail population as a whole, could pose a bottleneck to gene flow and lead to population structuring. Finally, F. hepatica has a wide host range, infecting multiple species of domestic and wild animals (Parr and Gray, 2000, Vignoles et al, 2001, Vignoles et al, 2004, Arias et al, 2012). This may allow the flow of genes amongst livestock species and maintain a reservoir of genetic diversity in wild animals.…”

A retrospective study on the metacercarial production of Fasciola hepatica from experimentally infected Galba truncatula in central France

“…The studies performed by our team on the cercarial productivity of F. hepatica in snails also demonstrated great variability. Indeed, the number of produced cercariae was dependent on the behavior of the first redia of the first generation (it remained alive during snail infection, or died early during the first weeks of experiment) (Augot and Rondelaud 2001) and also on the species of the definitive host from which the eggs of F. hepatica are collected (Vignoles et al 2001). In these conditions, it is logical to wonder what course to follow for the commercial production of metacercariae by asking the following three questions: What snail populations might be used for experimental infections?…”