No abstract

In this study, we present an optimised colourimetric and a lateral flow LAMP assay for the detection of Haemonchus contortus in small ruminant faecal samples. Using a previously published LAMP primer set, we made use of commercially available colourimetric LAMP and lateral flow kits and combined this into an optimised diagnostic assay which was then tested on field faecal samples from Eastern and South-Eastern Hungary as well as a pure H. contortus egg faecal sample from Košice, Slovakia. Both assays showed no conflicts in visual detection of the results. Additionally, we modified and tested several centrifuge-free DNA extraction methods and one bead-beating egg lysis DNA extraction method to develop a true point of care protocol, as the source of the starting DNA is the main rate-limiting step in farm-level molecular diagnosis. Out of the various methods trialed, promising results were obtained with the magnetic bead extraction method. Sample solutions from the Fill-FLOTAC® technique were also utilised, which demonstrated that it could be efficiently adapted for field-level egg concentration to extract DNA. This proof of concept study showed that isothermal amplification technologies with a colourimetric detection or when combined with a lateral flow assay could be an important step for a true point of care molecular diagnostic assay for H. contortus.

No abstract

Gastrointestinal parasitism in ruminant animals is a cause of major economic loss incurred by the livestock industry. Regardless of the frequency of the adopted therapeutic and prophylactic deworming strategies, the parasitic burden in a farm should be assessed regularly. One of the most widely used techniques to do so is the microscopic faecal egg examination and faecal egg counting method. Despite the technique being almost a century old from its first adoption, the principle behind the newer techniques of faecal egg examination is the same. This technique is still being used in routine farm screening and monitoring gastrointestinal parasitic load and faecal egg count reduction testing to assess the anthelmintic efficacy of the drugs used. Thus, the tool remains a choice for preliminary screening for important parasites and the subsequent deworming strategy. Our study here was part of a larger survey on the treatment efficiency as well as a broad epidemiological study of the trichostrongyle parasites in Hungary. We present a preliminary report on the detection of common gastrointestinal parasites from two farms in Hungary, including a species-specific confirmatory microscopy for Haemonchus contortus eggs.

Gastrointestinal parasites are ubiquitous. They occur both in wild and domesticated animals. Among such parasites of veterinary importance is the trichostrongyle worms, out of which the Haemonchus contortus species is regarded as the most pathogenic one in the small ruminant industry. The occurrence of this parasite in the sheep flock is now very well documented and an established fact in Europe, although the parasite was original of the warmer climatic region. Studies on the cross-transmission of H. contortus between the wild and domesticated animals are also on the rise although the question of the direction of transmission is still debated. This is an important area that needs to be addressed as it could potentially contribute indirectly to mitigating anthelmintic resistance. Hungary also has reported its share of the occurrence of the parasite, mainly in the sheep flock and a certain population of roe deer. The study presented here is the preliminary results of a diagnostic case study that confirms the presence of H. contortus in wild ruminant deer species that are close to the domesticated sheep population.