Although Echinostoma robustum (currently a synonym of E. miyagawai) was reported in the Americas based on molecular data, morphological support on adult parasites is still required. Herein, a new species of Echinostoma is described based on worms found in a chicken from Brazil. Molecular phylogenetic analyses based on 28S (1063 bp), ITS (947 bp) and Nad-1 (442 bp) datasets reveal the inclusion of the new species within Echinostoma ‘revolutum’ species complex. Moreover, it was verified the conspecificity between cercariae previously identified as E. robustum in Brazil [identical ITS and only 0.3% of divergence (1 nucleotide) in Nad-1]. Species discovery analyses show that these two isolates form an independent lineage (species) among Echinostoma spp. Compared to E. miyagawai, the new species presents relatively high divergence in Nad-1 (7.88–9.09%). Morphologically, the specimens are distinguished from all nominal species from the ‘revolutum’ species complex by the more posterior position of the testes (length of post-testicular field as a proportion of body length about 20%). They further differ from E. miyagawai and South American Echinostoma spp. by the higher proportion of forebody to the body length. Therefore, combined molecular and morphological evidence supports the proposal of the species named here as Echinostoma pseudorobustum sp. nov.

Our study yielded a list of ticks found on amphibians and reptiles at five sites within seasonally dry Amazon forest in Mato Grosso State, central Brazil, in addition to new host records for A. rotundatum. We collected 431 tick specimens: 79 larvae, 115 nymphs, 38 females, and 199 males belonging to A. humerale, A. rotundatum, and Amblyomma sp., on 39 anurans and 21 reptiles. The toads R. guttatus and R. margaritifera and the frog L. pentadactylus are new hosts for A. rotundatum.

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An in vitro experiment was carried out to assess the effect of fungal isolates of the genus Arthrobotrys, Duddingtonia, Monacrosporium and Nematoctonus on infective Strongyloides papillosus larvae. A suspension of 1,000 infective S. papillosus larvae was dripped on to Petri dishes containing fungi grown in agar-water. There was a statistically significant difference (p<0.05) among all the isolates and the fungus-free control. Comparing the results between isolates, difference was observed in some isolates of the genus Arthrobotrys (CG 719, I40, A1, A2, C1, B1), D. flagrans (CG722), Monacrosporium (CGI, SF53, NF34A) and N. robustus (D1) that showed a better capture and destruction results and consequently a greater decrease in the average of the uncaptured larvae recovered. The results showed that there may be variations in the predatory capacity of different species and among fungal isolates of the same species on Strongyloides papillosus and indicated that nematophagous fungi may be used for the biological control of this helminth. WALLER, 1998;JACOBS et al., 2016;TAYLOR et al., 2016). Infections by this parasite can cause gastrointestinal disturbances (enteritis, diarrhea and loss of appetite), affect body weight and delay growth and sudden death syndrome can occur (MEHLHORN, 2016;PIENNAR et al., 1999;TAIRA et al., 1992).In Brazil, benzimidazole and macrocyclic lactone anthelmintics are the principal forms of control used against gastrointestinal nematode parasites of ruminants (BOWMAN, 2010;CHARLES;FURLONG, 1996). However, the public health significance of anthelmintic drug residues in products of animal origin, the presence of these drugs in animal feces, their negative influence on biodiversity and agricultural ecosystem sustainability (due to the heavy reliance on systematic and sometimes abusive therapeutic use) and reports of helminth strains tolerant or resistant to different anthelmintic groups have triggered investigation into alternative methods for the sustainable control of gastrointestinal nematodes of ruminants (CAI et al., 2016;GRONVOLD et al., 1996;SUAREZ, 2002). The non-chemotherapeutic approach to the control of nematode gastrointestinal parasites of ruminants using nematophagous fungi as biological Campos et al. Acta Veterinaria Brasilica March 11 (2017) [213][214][215][216][217][218] 214 control agents showed consistent results (LARSEN, 2000;PAZ-SILVA et al., 2011). Because of differences in the nematophagous capacities of these fungi, studies to distinguish the species and the variations among them are required (ARAÚJO et al., 2004a;CARVALHO;BERNARDO;.The purpose of this study was to evaluate the activity of Brazilian isolates of nematophagous fungi of the Arthrobotrys, Duddingtonia, Monacrosporium and Nematoctonus genera against S. papillosus larvae in laboratory conditions. MATERIALS AND METHODSCultures of 17 fungal isolates of the Arthrobotrys, Duddingtonia, Monacrosporium and Nematoctonus genera (Table 1), grown on 1.7% corn meal agar culture media (CMA, DIFCO ® ) in test tubes, we...

Extensive rearing systems enable higher occurrence of helminths, which is a hindrance in poultry farming, significantly affecting productivity. A survey was conducted to determine the prevalence of gastrointestinal helminths in chickens reared in extensive system in the city of Viçosa, Minas Gerais, Brazil between December 2017 to September 2018. A total of 5579 specimens were recovered from the gastrointestinal tracts of most animals (81.55% of prevalence). Of the positive poultries, only 41.67% had mixed infections, and of these, more than 90% were nematodes and cestodes co-infections. Three nematodes (Ascaridia galli, Heterakis gallinarum, Capillaria sp.), seven cestodes (Raillietina tetragona, R. echinobothrida, R. cesticillus, Choanotaenia infundibulum, Hymenolepis cantaniana, H. carioca and Davainea proglottina) and two trematodes (Postharmostomum commutatum and Echinostoma sp.) species were identified. The most dominant helminth species was H. gallinarum (60.19%), which also presented higher average intensity (35.46 ± 0.65) and abundance (21.34 ± 3.01) among all recovered species. The tapeworm species correspond to 42.23% of prevalence and the trematodes correspond to only 3.40%. Despite the scarcity of data in the Brazilian literature on poultry helminths reared in extensive systems, regional parasitological surveys are important. It is expected that these results will contribute to the adoption of prophylactic measures and alternative control strategies in order to reduce the risk of helminth infection in poultry.

Three experimental assays with Duddingtonia flagrans (isolated AC001) were carried out. The growth of the genus Duddingtonia present in formulation of rice bran, its predatory capability on Oesophagostomum spp. infective larvae (L) in petri dishes (assay 1), its action in faecal cultures with eggs of that parasite (assay 2) and isolate's capability of predation after passing through gastrointestinal tract of swine (assay 3) was evaluated. At assay 3, feces were collected at time intervals of 12, 24, 36, 48, and 60 h after feed animals with the formulation. Assays 1 and 2 showed a statistical difference (p < 0.01) by the F test when comparing the treated group with the control group. At the both assays, was observed in the treated group a reduction percentage of 74.18% and 88.38%, respectively. In assay 3, there was a statistical difference between the treated group and the control group at all collection times (p < 0.01). Regarding the collection periods, there was no statistical difference over time in the treatment group (p > 0.05). The results demonstrate that the fungal isolate AC001 formulated in rice bran can prey on L of Oesophagostomum spp., in vitro and after passing through the gastrointestinal tract, without loss of viability. This isolate may be an alternative in the control of Oesophagostomum spp. in swine.

Echinostomatid digeneans belonging to the genus Rhopalias are intestinal trematodes found mainly in opossums in the New World. The genus comprises seven species, but their life cycles and intermediate hosts have been unknown until now. During our long-term study carried out in freshwater habitats within the state of Minas Gerais, Southeast Brazil, echinostomatid cercariae lacking collar spines were found in planorbid snails Biomphalaria glabrata, Biomphalaria straminea, Drepanotrema lucidum and Gundlachia ticaga in six different batches of snail samples collected between 2010 and 2019. Morphologically, the larvae reported herein are morphologically consistent with each other and characterized by the presence of 2–3 large ovoid or spherical corpuscles in each main duct of the excretory system, resembling to Cercaria macrogranulosa previously described from the same region of Brazil. Partial sequences of the ITS (ITS1-5.8S-ITS2) region and 28S gene of the nuclear ribosomal RNA operon, and partial sequences of mitochondrial nad1 and cox1 genes were obtained and compared with the data available for members of the family Echinostomatidae. Nuclear markers indicate that all samples of cercariae evaluated in the present study can be assigned to Rhopalias, but distinct from North American isolates of Rhopalias macracanthus, Rhopalias coronatus and Rhopalias oochi (divergence 0.2–1.2% in 28S and 0.8–4.7% in ITS). The lack of differences verified in both 28S and ITS in 5 out 6 studied samples suggested that they belong to the same species. However, nad1 sequences revealed that our cercariae correspond to three distinct species of Rhopalias (interspecific divergence: 7.7–9.9%), named here as Rhopalias sp. 1, found in B. straminea and G. ticaga, Rhopalias sp. 2 found in B. glabrata and D. lucidum, and Rhopalias sp. 3 also found in D. lucidum. They also differ by 10.8–17.2% from a North American isolate of R. macracanthus sequenced in this study. The cox1 sequences obtained for Rhopalias sp. 1 and Rhopalias sp. 2 (but not Rhopalias sp. 3) reveal that they are distinct from North American isolates of R. macracanthus (genetic divergence 16.3–16.5% and 15.6–15.7%, respectively), R. coronatus (9.2–9.3% and 9.3–9.5%) and Rhopalias oochi (9.0% and 9.5–10.1%). Encysted metacercariae with general morphology similar to that of the body of cercariae were found in tadpoles of Rhinella sp. from the same stream where snails harbored Rhopalias sp. 2, suggesting that the amphibians could act as second intermediate hosts of species of Rhopalias. Data obtained provide the first insights into the life cycle of this unusual echinostomatid genus.