Toxocara cati (Nematoda: Ascarididae) in Didelphis albiventris (Marsupialia: Didelphidae) from Brazil: a case of pseudoparasitism

Abstract

Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.Keywords: Opossum, pseudoparasitism, Toxocara cati. ResumoOvos de Toxocara cati foram encontrados nas fezes de Didelphis albiventris oriundos de um ambiente peridomiciliar urbano no Brasil. A negatividade dos exames de fezes após um curto período de cativeiro dos gambás e a ausência de nematódeos ascaridídeos durante a necropsia sugerem a ocorrência de pseudoparasitismo. As implicações dos achados para a epidemiologia da toxocarose são discutidas.Palavras-chave: Gambás, pseudoparasitismo, Toxocara cati. Anthropogenic environmental changes have led to the overlap of habitats and increased contact between wildlife and domestic animals, which can result in the transmission of helminth species from these hosts (spillover), a phenomenon widely discussed in recent times (reviewed by DASZAK et al., 2000;THOMPSON, 2013). However, studies on the possible involvement of wild animals in the life cycle of parasites from domestic animals are comparatively scarce (THOMPSON, 2013).Among the wildlife animals affected by human-caused environmental changes is the white-eared opossum, Didelphis albiventris Lund, 1840, a marsupial with a high potential for adaptation to urban areas (CÁCERES, 2002;SOUSA et al., 2012). In these areas, there is considerable overlap of the habitat of these didelphids and domestic animals, such as cats and dogs. Although not well known, the possibility of parasite transmission between felines and marsupials is real. Moreover, the fact that opossums act as reservoir hosts of pathogens that are of medical and veterinary importance (THATCHER, 2006) should be considered as a warning.In this case report, during the coproparasitological analysis of two young specimens of D. albiventris (males, weighing about 400 g), immature eggs of Toxocara cati (SCHRANK, 1788), an ascaridid parasite of felids with a worldwide distribution, were found, characterizing cases of pseudoparasitism.The opossums, captured in December 2013 on the premises of the Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil, were individually kept in cages containing food and water ad libitum for three days. All feces obtained during the captivity period were evaluated daily. Initially, the search for proglottids of cestodes and largersized nematodes that were possibly eliminated in the feces was performed macroscopically, and the fecal aliquots were processed using the spontaneous sedimentation method and analyzed by light microscopy. In parallel, samples of feces from cats (n = 12) obtained in the same habitat where opossums were caught were examined by the same parasitological method. The eggs of the helminths found we...

Updated checklist of helminths found in terrestrial mammals of Argentine Patagonia

“… Didelphis albiventris , Brazil, Pinto et al (2014). Herpailurus yagouaroundi , (captive) Huancayo, Peru, Cruz Hurtado & Muñoz Huamaní (2016).…”

“… Didelphis albiventris , Brazil, Pinto et al . (2014). Didelphis albiventris , Buenos Aires, Argentina, Illia et al (2018).…”

Prevalence, abundance and intensity of eggs and oocysts of gastrointestinal parasites in the opossum Didelphis virginiana Kerr, 1792 in Yucatan, Mexico

“…Rueda et al (2014) reported a frequency of 60 % (9/15) of Ancylostoma sp., in the feces of D. marsupialis in Colombia, with a lesser frequency that was found in the present study. In Brazil, Pinto et al (2014) found Toxocara cati in the feces of D. albiventris .…”

Prevalensi Infeksi Toxocara Cati pada Kucing Peliharaan di Kecamatan Banyuwangi

“…Penularan toxocariasis juga dipengaruhi oleh suhu musim dan perbedaan wilayah georafi suatu daerah (Motazedian, et al, 2006). Kucing yang tidak dikandangkan bisa terifeksi T.cati dari lingkungan yang telah terkontaminasi dengan telur dari T.cati, peneletian di Shiras menunjukkan sangat mudah terkontaminasi T.cati melalui feses kucing liar yang berkeliaran secara bebas di daerah atau tempat umum, maupun melalui tanah yang terkontaminasi (Motazedian, et al, 2006;Zain, et al, 2015) karena kebiasaan kucing yang mengubur feses mereka di tanah sehingga kemungkina infeksi melalui tanah juga tinggi, adanya interaksi antara kucing dengan hewan mamalia liar lainnya meningkatkan resiko infeksi, terutama tikus yang memiliki peran sebagai inang perantara pada penyebaran toxocariasis (Overgaauw and Knapen, 2013;Pinto, et al, 2014). Intensitas infeksi toxocarsiasis lebih menunjukkan hasil hubungan yang signifikan pada kucing liar, dan menunjukkan hasil hubungan yang tidak signifikan pada kucing peliharaan (Akeredulo and Sowemimo, 2014).…”