Composição da malacofauna terrestre urbana de União da Vitória, extremo sul do Paraná, Brasil / Composition of the urban terrestrial malacofauna of União da Vitória, extreme south of Paraná, Brazil

Os gastrópodes terrestres enfrentam um grave problema, além das alterações nos ambientes naturais, sofrem a competição direta com espécies exóticas e pela introdução demasiada dessas espécies. Nesse sentido, este estudo teve como objetivo realizar um inventário das espécies de gastrópodes terrestres em União da Vitória, extremo sul do Paraná, com a finalidade de fornecer informações para análises ecológicas e taxonômicas em uma área urbana. Na zona urbana central foram amostradas 20 áreas domiciliares, durante os meses de junho, setembro e dezembro de 2019 e março de 2020. Em cada local, os gastrópodes foram coletados usando três quadrantes com área amostral de 5 m2. As amostragens envolveram padronização de esforço amostral através do método de coleta ativa manual. Um total de 10 famílias, 15 espécies e 1.835 espécimes foram registrados na biocenose estudada. As espécies Leptinaria sp., Happia insularis, Belocaulus angustipes e Succinea aff. burmeisteri foram encontradas em apenas uma coleta. As espécies dominantes foram Bradybaena similaris (70,3%, n = 1.290), Phyllocaulis soleiformis (10,7%, n = 196) e Achatina fulica (7,85%, n = 144) totalizando 88,85 % dos espécimes coletados. As espécies constantes foram Bradybaena similaris, Achatina fulica, Cornu aspersum, Limax maximus, Limacus flavus, Phyllocaulis soleiformis e Meghimatium pictum. Entre as espécies encontradas, sete são espécies exóticas introduzidas. A utilização de uma metodologia de coleta adequada para ambiente urbano possibilitou a amostragem de espécimes que apresentam preferência por hortas, jardins, plantações, terrenos baldios e solo. De uma maneira geral, a fauna de moluscos foi subrepresentada, entretanto, a riqueza tanto das espécies exóticas quanto as espécies nativas foi equivalente, o que é esperado em centros urbanos.

The effect of biologically active compounds in the mucus of slugs Limax maximus and Arion rufus on human skin cells

Molluscs are one of the sources of biologically active substances, which are now intensively studied, especially for their anti-cancer properties. Malignant melanoma originates from melanocytes, develops very quickly and is associated with poor prognosis. Therefore, the aim of the study was to assess the properties of biologically active compounds in sterile mucus isolated from slugs Limax maximus and Arion rufus. Tested mucus were isolated using the new self-developed method which is safe for the environment and the animal donors. The impact of the mucus on human keratinocytes CCD 1106 KERTr and malignant melanoma cells A-375 was examined using MTT assay and SRB assay, which allowed us to determine the cell metabolic activity and cell number after treating them with slug mucus isolated from Limax maximus and Arion rufus decreased human keratinocytes and melanoma cells metabolic activity as well as manifested properties of reducing the number of cells in both tested cell lines, and therefore can be a source of biologically active substances with anticancer potential.

Infectivity of gastropod-shed third-stage larvae of Angiostrongylus vasorum and Crenosoma vulpis to dogs

Background Metastrongyloid parasites Angiostrongylus vasorum and Crenosoma vulpis infect wild and domestic canids and are important pathogens in dogs. Recent studies indicate that gastropod intermediate hosts infected with various metastrongyloids spontaneously shed infective third-stage larvae (L3) into the environment via feces and mucus under laboratory conditions. Shed L3 retain motility up to 120 days, but whether they retain infectivity was unknown. Methods To assess the infectivity of shed L3, the heart/lungs of six red foxes (Vulpes vulpes) were obtained from trappers in Newfoundland, Canada. Lungs were examined for first-stage larvae (L1) by the Baermann technique. A high number of viable A. vasorum L1 and a low number of C. vulpis L1 were recovered from one fox; these were used to infect naïve laboratory-raised Limax maximus. L3 recovered from slugs by artificial digestion were fed to two naïve purpose-bred research beagles (100 L3/dog). L1 shed by these two dogs was used to infect 546 L. maximus (2000–10,000 L1/slug). L3 shedding was induced by anesthetizing slugs in soda water and transferring them into warm (45 °C) tap water for at least 8 h. Shed L3 recovered from slugs were aliquoted on romaine lettuce in six-well tissue culture plates (80–500 L3/well) and stored at 16 °C/75% relative humidity. Four naïve research beagles were then exposed to 100 L3/dog from larvae stored for 0, 2, 4, or 8 weeks, respectively, after shedding. Results All four dogs began shedding C. vulpis L1 by 26–36 days post-infection (PI). All four dogs began shedding A. vasorum L1 by 50 days PI. Conclusions L3 infectivity for the definitive host was retained in both metastrongyloids, indicating the potential for natural infection in dogs through exposure from environmental contamination. As an additional exposure route, eating or licking plant or other material(s) contaminated with metastrongyloid L3 could dramatically increase the number of dogs at risk of infection from these parasites. Graphic Abstract

Detection of Crenosoma spp., Angiostrongylus vasorum and Aelurostrongylus abstrusus in Gastropods in Eastern Austria

Canine and feline cardiorespiratory parasites are of utmost relevance in veterinary medicine. Key epizootiological information on major pet metastrongyloids, i.e., Angiostrongylus vasorum and Crenosoma vulpis infecting dogs, and Aelurostrongylus abstrusus and Troglostrongylus brevior infecting cats, is missing from Austria. This study investigated their occurrence in 1320 gastropods collected in the Austrian provinces of Styria, Burgenland, Lower Austria, and in metropolitan Vienna. Metastrongyloid larvae were microscopically detected in 25 samples, and sequence analysis confirmed the presence of metastrongyloids in nine samples, i.e., A. vasorum in one slug (Arion vulgaris) (0.07%), C. vulpis in five slugs (one Limax maximus and four A. vulgaris) (0.4%), A. abstrusus in two A. vulgaris (0.17%), and the hedgehog lungworm Crenosoma striatum was detected in one A. vulgaris. The present study confirms the enzooticity of major cardiorespiratory nematodes in Austria and that canine and feline populations are at risk of infection.