Parasite-host relations and new reports of helminths for Rhinella dorbignyi (Duméril & Bibron, 1841) (Anura: Bufonidae) from Neotropical region.

This study aimed to analyze helminth assemblage in Rhinella dorbignyi regarding host gender, size and mass in two sampling sites in southern Brazil, and to report new parasite associations. Anurans (n = 100) were collected in two localities from Rio Grande do Sul (RS) state, Brazil, from 2017 to 2020. Nineteen taxa (adults and larval forms) belonging to Nematoda, Acanthocephala, Digenea, and Cestoda were found in different infection sites. Cosmocercidae gen. spp., Physaloptera liophis, Catadiscus sp., and Cylindrotaenia americana were the dominant taxa in helminth assemblage. Female anurans showed higher helminth species richness than males considering the total sample (two localities) or one of the two localities. However, prevalence and mean intensity of infection did not show any significant difference between genders. Mean intensity of infection was significantly higher (19.52) in Laranjal locality. Host body size does not influence helminth abundance, as infections did not show significant correlation snout-vent length (SVL) nor body mass (BM) of anurans. The findings reveal anurans of R. dorbignyi may be intermediate, paratenic and definitive host for these parasites. Plagiorchioidea helminths (Digenea), Physaloptera liophis, larvae of Acuariidae and Spiroxys sp. (Nematoda), and cystacanth of Lueheia sp. (Acanthocephala) constitute new records for R. dorbignyi. Additionally, this is the first record of Cylindrotaenia americana larvae in this host species. Resulting information increases the knowledge on biodiversity and parasite-host relations and may help future conservation programs developed in ecosystems in the extreme south of Brazil.

Digenetic helminths of Leptodactylus latrans (Anura: Leptodactylidae) and Rhinella dorbignyi (Anura: Bufonidae) in southern Brazil / Helmintos digenéticos de Leptodactylus latrans (Steffen, 1815) (Anura: Leptodactylidae) e Rhinella dorbignyi (Duméril & Bibron, 1841) (Anura: Bufonidae) no sul do Brasil

Anuros são citados como hospedeiros para uma vasta diversidade de helmintos, entretanto as informações relativas a helmintofauna de anuros no Brasil, são pouco abordadas, sobretudo na região sul do Rio Grande do Sul. Este estudo tem como objetivo registrar os helmintos digenéticos parasitos de Leptodactylus latrans e Rhinella dorbignyi no extremo sul do Brasil. Para realização da pesquisa foram coletados entre agosto de 2017 e agosto de 2018, 60 espécimes de anuros, L. latrans (n= 30) e R. dorbignyi (n= 30), os quais foram necropsiados e os helmintos coletados, fixados e corados para identificação conforme bibliografia especifica para cada grupo. Os índices de infecção estimados foram prevalência (P%), intensidade média de infecção (IMI) e abundância média (AM). Do total de anuros examinados, 28 indivíduos (46,66%) apresentaram helmintos digenéticos, totalizando 255 espécimes de parasitos. Leptodactylus latrans esteve parasitado por Gorgoderina megacysta (P = 40%), Haematoloechus freitasi (P = 23,33%), Catadiscus spp. (P = 30%), Plagiorchioideae gen. spp. (P = 63,33%), e Halipegus sp. (P = 3,33%), enquanto R. dorbignyi apresentou infecção por Gorgoderina sp. (P = 3,33%), Haematoloechus sp. (P = 3,33%), Catadiscus sp. (P = 3,33%), Plagiorchioideae gen. sp. (P = 3,33%), e Diplostomidae gen. spp. (metacercárias) (P = 6,66%).

Even though anurans have been hosts to an array of helminths, data on the helminth fauna of anurans in Brazil are scarce. This study aims at reporting digenetic helminths on Leptodactylus latrans (Steffen, 1815) and Rhinella dorbignyi (Duméril & Bibron, 1841) in southern of Brazil. Sixty specimens of anurans L. latrans (n= 30) and R. dorbignyi (n= 30) were collected between August 2017 and August 2018. Then, necropsy was performed and helminths were collected, fixed and dyed to be identified in agreement with specific bibliography. Estimated infection indices were prevalence (P%), mean intensity of infection (MII) and mean abundance (MA). Twenty-eight anurans (46.66%) exhibited digenetic helminths, totalizing 255 parasite specimens. Leptodactylus latrans was infected with Gorgoderina megacysta Mañé-Garzón & González, 1978 (Gorgoderidae) (P = 40%), Haematoloechus freitasi Mané Garzón & Solares, 1959 (Haematoloechidae) (P = 23.33%), Catadiscus spp. (Diplodiscidae) (P = 30%), Plagiorchioideae fam. gen. spp. (P = 63.33%) and Halipegus sp. (Derogenidae) (P = 3.33%), whereas R. dorbignyi was infected with Gorgoderina sp. (P = 3.33%), Haematoloechus sp. (P = 3.33%), Catadiscus sp. (P = 3.33%), Plagiorchioideae fam. gen. sp. (P = 3.33%) and Diplostomidae gen. spp. (metacercariae) (P = 6.66%).

Digenetic helminths of Leptodactylus latrans (Anura: Leptodactylidae) and Rhinella dorbignyi (Anura: Bufonidae) in southern Brazil / Helmintos digenéticos de Leptodactylus latrans (Steffen, 1815) (Anura: Leptodactylidae) e Rhinella dorbignyi (Duméril & Bibron, 1841) (Anura: Bufonidae) no sul do Brasil

Anuros são citados como hospedeiros para uma vasta diversidade de helmintos, entretanto as informações relativas a helmintofauna de anuros no Brasil, são pouco abordadas, sobretudo na região sul do Rio Grande do Sul. Este estudo tem como objetivo registrar os helmintos digenéticos parasitos de Leptodactylus latrans e Rhinella dorbignyi no extremo sul do Brasil. Para realização da pesquisa foram coletados entre agosto de 2017 e agosto de 2018, 60 espécimes de anuros, L. latrans (n= 30) e R. dorbignyi (n= 30), os quais foram necropsiados e os helmintos coletados, fixados e corados para identificação conforme bibliografia especifica para cada grupo. Os índices de infecção estimados foram prevalência (P%), intensidade média de infecção (IMI) e abundância média (AM). Do total de anuros examinados, 28 indivíduos (46,66%) apresentaram helmintos digenéticos, totalizando 255 espécimes de parasitos. Leptodactylus latrans esteve parasitado por Gorgoderina megacysta (P = 40%), Haematoloechus freitasi (P = 23,33%), Catadiscus spp. (P = 30%), Plagiorchioideae gen. spp. (P = 63,33%), e Halipegus sp. (P = 3,33%), enquanto R. dorbignyi apresentou infecção por Gorgoderina sp. (P = 3,33%), Haematoloechus sp. (P = 3,33%), Catadiscus sp. (P = 3,33%), Plagiorchioideae gen. sp. (P = 3,33%), e Diplostomidae gen. spp. (metacercárias) (P = 6,66%).(AU)

Even though anurans have been hosts to an array of helminths, data on the helminth fauna of anurans in Brazil are scarce. This study aims at reporting digenetic helminths on Leptodactylus latrans (Steffen, 1815) and Rhinella dorbignyi (Duméril & Bibron, 1841) in southern of Brazil. Sixty specimens of anurans L. latrans (n= 30) and R. dorbignyi (n= 30) were collected between August 2017 and August 2018. Then, necropsy was performed and helminths were collected, fixed and dyed to be identified in agreement with specific bibliography. Estimated infection indices were prevalence (P%), mean intensity of infection (MII) and mean abundance (MA). Twenty-eight anurans (46.66%) exhibited digenetic helminths, totalizing 255 parasite specimens. Leptodactylus latrans was infected with Gorgoderina megacysta Mañé-Garzón & González, 1978 (Gorgoderidae) (P = 40%), Haematoloechus freitasi Mané Garzón & Solares, 1959 (Haematoloechidae) (P = 23.33%), Catadiscus spp. (Diplodiscidae) (P = 30%), Plagiorchioideae fam. gen. spp. (P = 63.33%) and Halipegus sp. (Derogenidae) (P = 3.33%), whereas R. dorbignyi was infected with Gorgoderina sp. (P = 3.33%), Haematoloechus sp. (P = 3.33%), Catadiscus sp. (P = 3.33%), Plagiorchioideae fam. gen. sp. (P = 3.33%) and Diplostomidae gen. spp. (metacercariae) (P = 6.66%).(AU)