Testing Methods and Samples Required

Ostertagia is one of the most economically significant parasites in cattle. Ostertagia is a roundworm that remains in the stomach and intestines of cattle where it causes damage to the gut wall.

Ostertagia is detrimental to the animal’s health as it results in lower feed intake and lower gut uptake. The effect ostertagia has in young stock is an overall reduction in weight along with a subsequent scour. While in dairy cows, body condition scores and milk production are reduced.

Older cattle develop immunity to ostertagia due to long-term exposure. As a result they are unlikely to develop the worm scour that is present in young cattle.

Cattle ingest the worms by grazing from early in the year. A strict control programme needs to be implemented where a herd presents as positive for the parasite by faecal egg counts or bulk milk testing.

If the brown stomach worm remains uncontrolled, herd performance is greatly reduced and some animals may die.