DNA tests to identify worm species

DNA tests can be used as an alternative to larval cultures to identify the different species of roundworm eggs in cattle faeces. The different worm species, and their relative proportions, can be calculated in 2-3 days and provide improved sensitivity and accuracy compared to traditional larval cultures. Specific tests are available for small brown stomach worm (Ostertagia ostertagi), barber’s pole worm (Haemonchus placei), stomach hair worm (Trichostrongylus axei), small intestinal worm (Cooperia oncophora) and hookworm (Bunostomum phlebotomum). A generic DNA test that detects all nematodes (pan-nematodae) is also available.

Identifying the level and species of roundworm infection in a mob is essential for making optimal decisions about if and when animals should be treated. They allow producers to design control programs and use suitable products to target the particular roundworms present. Different worm types vary in their impact on animal welfare, and their economic effect on cattle production. The DNA tests are suitable for before and after DrenchCheck studies. They can also assist in identifying drench resistant strains that will likely require modified treatment strategies.