Angiostrongylus vasorum: Experimental Infection and Larval Development inOmalonyx matheroni

Abstract

The susceptibility and suitability of Omalonyx matheroni as an intermediate host of Angiostrongylus vasorum and the characteristics of larval recovery and development were investigated. Mollusks were infected, and from the 3rd to the 25th day after infection, larvae were recovered from groups of 50 individuals. The first observation of L2 was on the 5th day, and the first observation of L3 was on the 10th day. From the 22nd day on, all larvae were at the L3 stadium. Larval recovery varied from 78.2% to 95.2%. We found larval development to be faster in O. matheroni than in Biomphalaria glabrata. Our findings indicate that this mollusk is highly susceptible to A. vasorum. Infective L3 were orally inoculated into a dog, and the prepatent period was 39 days. This is the first study to focus on O. matheroni as an intermediate host of A. vasorum.

Gallus gallus domesticus: Paratenic host of Angiostrongylus vasorum

“…The elimination of L1 in the feces of the dog demonstrates that the life cycle of A. vasorum is complete in the laboratory when using chicken as a paratenic host after ingestion of infected snails. The pre-patent period of 51 days confirms reports in the literature of a variation of the pre-patent period between 28 and 108 days after infection (Oliveira-Júnior et al, 2006;Mozzer et al, 2011). The use of fenbendazole was an effective therapeutic approach for the treatment of the dog, as observed in other studies of dogs infected with A. vasorum and treated with the same active ingredient (Martin et al, 1993;Brennan et al, 2004).…”

“…Moreover, infection via the ingestion of infected snails requires an estimate of the average number of larvae being inoculated into each chicken. There is individual variation in the recovery of L3 from each snail, as demonstrated by Mozzer et al (2011). Those authors infected snails of the genus Omalonyx and noted that some individuals had higher larval recovery due to increased penetration of the larvae during mollusk infection.…”

“…The parasites were obtained from 170 individuals from the Omalonyx matheroni species of mollusks, which were individually infected using polystyrene culture plates with 10 mm wells (Manufacturer: TPP). A total of 500 L1 (for each snail) were deposited on lettuce leaf fragments that were ingested by the snails, according to the methodology described by Mozzer et al (2011). A total of 25 days after infection, 90 snails were randomly separated into groups of 10.…”

“…First-stage larvae (L1) in the feces of the definitive hosts infect snails via penetration of the integument or ingestion. In the snail tissues, 2 developmental stages occur, converting the parasites into third stage larvae (L3) (Rosen et al, 1970;Guilhon and Cens, 1973;Grewal et al, 2003;Morley, 2010;Mozzer et al, 2011 (Barç ante et al, 2003). Another mechanism through which definitive hosts become infected is via the ingestion of paratenic hosts, such as amphibians (Bolt et al, 1993).…”

Predicting the distribution of Omalonyx (Mollusca: Pulmonata: Succineidae) species from literature review, museum databases and new sampling efforts in Brazil

“…They can act as agricultural plagues (Olazarri 1979, Garcia et al 2012 and are agents in the control of water-cress (Poi de Neiff et al 1977). They can also act as intermediate hosts of an avian trematode, Leucochloridium (Lutz 1921, Travassos 1928, in the wild and of the nematodes Angiostrongylus costaricensis and A. vasorum in the laboratory (Montresor et al 2008, Mozzer et al 2011.…”