Applying FAMACHA for effective worm control

During a recent MLA webinar, independent animal health consultant Maxine Lyndal-Murphy outlined how the FAMACHA test for barber’s pole worm is performed and how the results can be used to better manage worm infections.

While rangeland goats run extensively in their natural environment are not greatly affected by worms, managing the health and production impacts of worms in goats held in depots and herds in high rainfall areas can be difficult.

One worm of particular note that is responsible for significant losses in the Australian goat industry is barber’s pole worm. The prompt identification of barber’s pole worm is critical in minimising losses, as these parasites feed directly from the animal’s blood supply in the fourth stomach and goats can very quickly progress from being mildly to severely anaemic.

The FAMACHA chart, named after the test’s developer Faffa Malan, (FAffa MAlan), and to reflect the use of a chart in diagnosis, involves making regular assessments of the mucus membranes in both eyes of goats and scoring on a scale of one to five, with five being severely anaemic.

Based on the test results, producers:

• Should carefully consider drenching any animals that are scored as being 3;
• are strongly advised to drench all animals of score 4; and
• are strongly advised to drench all animals of score 5, or consider seeking veterinary advice.

Keeping individual test records for each animal can be very helpful in determining those animals most susceptible to worm infections, particularly if the test is performed before and after drenching. This allows producers to decide which animals should be culled, as these animals may expose the rest of the herd to worms and could also be likely to pass susceptibility on to progeny (download the factsheet about KIDPLAN EBV definitions to learn more about this. The value of maintaining test records is supported by research undertaken in the Goondiwindi area on sheep farms that indicates removing 21% of the ‘wormy tail’ of animals affected can reduce the worm egg count in the rest of the herd by 50%.

The FAMACHA test also enables producers to practise selective drenching, rather than taking a more global approach, and further helping to prevent worm resistance to anthelmintic agents in goat herds.

Other key strategies to prevent worm infections include:

• Selective culling of animals with a predisposition to worm infection;
• implementing an appropriate rotational grazing plan that avoids having goats grazing on short pastures;
• incorporating browse, particularly during the wet season;
• keeping animals that may be more susceptible (pregnant, lactating and young animals) separate from those that may have stronger resistance; and
• ensuring that goats are not exposed to other health or nutritional issues that may increase their susceptibility to worm infections.

In terms of drenches, the application for the registration of Barbervax vaccine as an agent for control of barber’s pole worm has recently been extended to cover goats and it is anticipated this will be available in time for the summer of 2016-17.

Further information

Watch the webinar or access other webinars in the series.

Contact your veterinarian to obtain a FAMACHA chart and to organise training about how to use it.

Read more about barber’s pole worm.

Access Going into Goats Module 9: Parasite control.