Multiplexed-tandem PCR (MT-PCR) assay to detect and differentiate gastrointestinal nematodes of alpacas

Abstract

BackgroundGastrointestinal nematodes (GINs) frequently infect South American camelids (alpacas and llamas) and cause economic losses due to reduced production of fiber, meat and/or leather. Our knowledge about the epidemiology and diagnosis of GINs in llamas and alpacas is limited, and reliable keys for the identification of the third-stage larvae (L3s) of some common nematodes (such as Camelostrogylus mentulatus) that infect alpacas and llamas remain undescribed. In this study, we modified two existing semi-quantitative multiplexed-tandem (MT)-PCR assays, originally developed for the GINs of sheep and cattle, to reliably detect and differentiate the common genera/species of GINs in the faeces of alpacas.ResultsFollowing the establishment of the MT-PCR assay using positive and negative control samples, alpaca faecal samples were tested to validate the assay to detect and differentiate nematode genera/species, including C. mentulatus, Cooperia spp., Haemonchus spp., Oesophagostomum spp., Ostertagia ostertagi, Teladorsagia circumcincta and Trichostrongylus spp. Sequencing of the MT-PCR products demonstrated specific (100%) amplification of the target nematode genera/species. Additionally, a comparison of results of the MT-PCR assay and the morphological identification of adult worms collected from the same 35 alpacas revealed that there was a good agreement (37–94%) between the two methods. However, some discrepancies were observed between the results of the MT-PCR assay and the morphological identification of adult worms.ConclusionsThe MT-PCR platform is an accurate, sensitive and rapid method for the diagnosis of GINs in alpacas, and it can be used as a substitute to larval culture to identify common nematodes in the faeces of alpacas and llamas.

Nemabiome metabarcoding shows a high prevalence of Haemonchus contortus and 1 predominance of Camelostrongylus mentulatus in alpaca herds in the northern UK

“…Camelids have also been reported to acquire other GINs which commonly infect sheep and cattle, including Trichostrongylus, Haemonchus, Cooperia, Ostertagia, and Nematodirus spp. (Bishop and Rickard, 1987;Hill et al, 1993;Rashid et al, 2018a;Rashid et al, 2018b), presumably resulting from co-grazing with ruminant livestock (Rashid et al, 2019).…”

Prevalence and molecular identification of Nematodirus helvetianus in camels in Iraq

“…However, most helminthiases are asymptomatic or without clinical manifestation, thus the herd may appear normal, despite performing below its full potential [3,4]. The genus Nematodirus belongs to trichostrongylids which are the most common helminths and are considered the most important nematodes that have an economic impact by afflicting ruminates, including camels and camelids [5,6]. Nematodirus is a nematode of the small intestine of large and small ruminants and exhibits a direct life cycle.…”

“…Nematodirus is a nematode of the small intestine of large and small ruminants and exhibits a direct life cycle. The genus Nematodirus consists of more than 45 species distributed in domestic ruminants worldwide [6,7]. Nematodirus helvetianus is frequently a parasite of cattle (generally named the twisted wireworm).…”