The vicuna (Vicugna vicugna) as a natural host of Dictyocaulus filaria in Peru

Abstract

Lungworm infection, or verminous pneumonia, is a parasitic disease that causes serious problems in small and large ruminants. Despite the fact that nematodes of the genus Dictyocaulus in cattle and sheep are the main cause of this disease, there are few studies on the natural infections of South American camelids. For this reason, this study aims to report the natural infection by Dictyocaulus filaria in vicunas (Vicugna vicugna) for the first time. During a shearing season (chaku) in Cuzco, Peru, two accidentally killed adult vicunas were submitted to the IVITA-Marangani research center in Cuzco for their respective necropsies. The tracheas of both vicunas had numerous nematodes, as seen during the necropsy. The nematodes were collected in 70% ethanol and were morphologically identified as D. filaria. Likewise, the DNA of six nematodes was extracted, and the ITS2 region and the 28S rRNA gene were amplified and sequenced. The nucleotide sequences of both genetic markers were up to 100% identical with previously reported D. filaria DNA sequences found in the goat yearlings from Turkey, sheep from Iran, Turkey, and India, and the argali from Uzbekistan, which confirmed the morphological diagnosis. This finding represents the first molecular confirmation of a natural D. filaria infection in a South American camelid. It will be necessary to carry out future studies to know the current situation of verminous pneumonia in domestic and wild South American camelids and to know the negative effects of the disease on them.