The research article focuses on detecting anthelmintic resistance in nematodes affecting livestock. It talks about the need to validate modified and new methods for resistance detection in different laboratories across the world, especially related to macrocyclic lactone resistance and resistance in cattle.

Background and Purpose

• The study begins with discussing the imminent need for improved methods to detect anthelmintic resistance in nematodes. This need is more pronounced for detecting macrocyclic lactone resistance (a commonly used anti-parasitic drug) and for resistance detection in nematodes infecting cattle.
• The primary purpose of the research is to propose and discuss revised and new methods for detecting anthelmintic resistance in nematodes affecting ruminants (animals like cattle and sheep), horses, and pigs.
• These proposed methods aim to stimulate international evaluation and discussions, with hopes that they could be future recommended strategies by the World Association for the Advancement of Veterinary Parasitology (WAAVP).

The Faecal Egg Count Reduction Test

• The article discusses modifications to interpreting the faecal egg count reduction test, a primary method for determining resistance in nematodes.
• It also suggests guidelines for its usage with persistent anthelmintics and continuous release devices (methods used for administering the drug).

New Testing Methods

• An egg hatch test for determining resistance to benzimidazole (a class of anthelmintic drugs) is described.
• The research also proposes a microagar larval development test. This test is used for detecting benzimidazole and levamisole (another class of anthelmintics) resistance, and creates third stage larvae that can be analyzed to detect resistant worms.
• It is suggested that the sensitivity of these two tests can be increased by using discriminating doses rather than lethal dose (LD50) values.
• The researchers also present the details of a PCR (Polymerase Chain Reaction) based test for an in-depth analysis of benzimidazole resistance in strongyles (a type of parasite) in sheep, goats, horses, and cattle.

Challenges and Future Research

• Despite its potential for ruminant trichostrongyles (a type of nematodes), the quantitative determination of gene frequency using real time PCR still requires further advancements before it can be used in the field.
• The research points out that except for faecal egg count reduction tests, there are no satisfactory tests for macrocylic lactone resistance, indicating the importance of this subject.
• Moreover, apart from treatment and slaughter trials, there are no validated tests for detecting resistance towards fasciolicide (a type of anthelmintics used against liver flukes) or for resistance detection in cestodes (a class of parasitic worms).