IDENTIFICATION OF RESPIRATORY AND GASTROINTESTINAL PARASITES OF THREE SPECIES OF PINNIPEDS (ARCTOCEPHALUS AUSTRALIS, ARCTOCEPHALUS GAZELLA, ANDOTARIA FLAVESCENS) IN SOUTHERN BRAZIL

Abstract

In order to improve understanding of parasitism in South American pinnipeds, respiratory and gastrointestinal samples were collected from 12 Arctocephalus australis (South American fur seal), one Arctocephalus gazella (Antarctic fur seal), and one Otaria flavescens (South American sea lion). Ova and larvae were microscopically identified from fecal samples and respiratory secretions collected from live A. australis undergoing rehabilitation at Centro de Recuperação de Animais Marinhos (CRAM-FURG) in Rio Grande, Rio Grande do Sul, Brazil during June-July 2012. Adult parasites were collected from the lungs and gastrointestinal tracts of animals that died while undergoing treatment or were found dead along the southern Brazil coast. Parasites were identified by polymerase chain reaction and DNA sequencing, microscopic examination, comparison with keys, and histologic examination of tissues. Lung parasites of the Parafilaroides genus (Metastrongyloidea, Filaroididae) were identified at necropsy in both A. australis and A. gazella and gastrointestinal parasites were found in all three species of pinniped studied. Gastrointestinal parasites identified in A. australis included the nematodes Contracaecum sp. and Pseudoterranova cattani, the cestodes Adenocephalus pacificus (previously Diphyllobothrium pacificum), one from the Tetrabothridae family and one undetermined, and the acanthocephalans Corynosoma sp. and Bolbosoma sp.; from A. gazella the nematode Contracaecum sp. and the acanthocephalan Corynosoma sp.; and from O. flavescens the acanthocephalan Corynosoma sp. Ova from fecal samples from A. australis represent ascarid nematodes, Parafilaroides sp., Adenocephalus pacificus, acanthocephalans, and an egg determined either to be a trematode or pseuophyllidean cestode. With limited information surrounding parasitism, these findings are an important contribution to knowledge of the health of Southern Hemisphere pinnipeds.

Fatal pulmonary parafilaroidiasis in a free-ranging subantarctic fur seal (Arctocephalus tropicalis) coinfected with two gammaherpesviruses and Sarcocystis sp.

“…In the present case, while there was mild, chronic bronchointerstial inflammatory response with mild remodeling, the most severe pathogenetic parasitic consequence appeared to involve airflow obstruction and alveolar emphysema with septal distortion and rupture. These findings are in agreement with previous observations of parafilaroidiasis in other pinnipeds, despite some variations among host species (MEASURES, 2001;JACOBUS et al, 2016). Our results suggest that Parafilaroides sp.…”

“…Pulmonary parafilaroidiasis cases by Parafilaroides sp. and P. normani have been reported, respectively, in South American and Antarctic fur seals (Arctocephalus gazella) from Brazil (JACOBUS et al, 2016), and in a subantarctic fur seal from South Africa (DAILEY, 2009). Additionally, thromboembolism associated with verminous pulmonary vasculitis by Parafilaroides decorus has been described in a Guadalupe fur seal (Arctocephalus philippii townsendi) (SEGUEL et al, 2018).…”

“…Parasitic respiratory disease by nematodes, including Otostrongylus circumlitus (Metastrongyloidea: Crenosomatidae) and Parafilaroides spp. (Metastrongyloidea: Filaroididae), are significant causes of morbidity and mortality in free-ranging pinnipeds (DAILEY, 2001;SIEBERT et al, 2007); however, there is limited information concerning Parafilaroides infection and associated pathology in South American pinnipeds (JACOBUS et al, 2016).…”

Diphyllobothriidae

“…Recently, A. pacificus has been identified in the South American fur seal, Arctophoca australis (syn. Arctocephalus australis), a definitive host in the coast of Brazil (Jacobus et al, 2016).…”

“…It measures from 1 m to 12 m, but could be up to 25 m in D. latus species (Table 1). It could live 10 to 15 years, but an infection lasting about 30 years has been reported (von Bonsdorff, 1977 Andersen, 1971Andersen, , 1975Andersen et al, 1987;von Bonsdorff, 1977;Dick and Poole, 1985;Kamo, 1999;Kuchta et al, 2015b;Rausch and Hilliard, 1970;Scholz et al, 2009;Torres, 2013;Torres et al, 1989aTorres et al, , 1993Yamane et al, 1989a;Yazaki et al, 1984; b Ando et al, 2001;Arizono et al, 2009b;Choi et al, 2015;Fang et al, 2015;Jeon et al, 2009;Kamo, 1999;Wicht et al, 2008b;Yamane et al, 1986;Yamasaki and Kuramochi, 2009;Yera et al, 2006;c Andersen, 1975;Andersen et al, 1987;Dick and Poole, 1985;Figueroa et al, 1979Figueroa et al, , 1980Kuchta et al, 2013;Rausch and Hilliard, 1970;Torres et al, 1981b; d Baer et al, 1967;Cattan et al, 1977;Escalante and Miranda, 1986;Hernández-Ortz et al, 2015;Jacobus et al, 2016;Jimenez et al, 2012;Kuchta et al, 2015b;…”