Vet’s Vision Phil Rennie Tauranga Vets

A recently published peer reviewed study has thrown new light on the common pitfalls of facial eczema control in New Zealand. The full article was released in the ‘The New Zealand Veterinary Journal’ following initial publication in the ‘Dairy New Zealand Technical Series’ a year ago.

A number of key points raised by Waikato veterinarian Emma Cuttance showed plenty of room for improvement, which is a timely reminder given the widespread damage caused by the disease last season, especially over the greater Waikato region.

This study involved blood testing 10 cows from each of 105 farms and results indicated facial eczema is generally poorly managed on New Zealand farms. Sub-clinical facial eczema is a problem on at least one-third of dairy farms in the North Island, and the Bay of Plenty would be no exception.

Spore counting is good for detecting trends, but to be most relevant, the same paddocks need to be tested each week on your farm. This clearly has implications on the value a farm can gain from grass samples submitted during the facial eczema season. Chicory and plantain, planted in pure swards, protect against facial eczema, while tall fescue may have some protective effect. Lime on the other hand has no effect on spore counts.

Of most importance is that zinc remains the best protection tool but under-dosage is common. In particular zinc in the water is the most common method but the least effective at achieving adequate zinc levels in the cows. It is possible for all zinc treatments to work but all methods can fail if the dosage is incorrect. The method is more likely to fail if a cow has control over her intake of zinc via water or feed.

Once zinc treatment is initiated farmers need to test a selection of cattle for zinc concentration in the blood and liver damage. Monitoring is important to provide assurance that your efforts are providing adequate protection. Moving forward, there appears to be a considerable opportunity for your local vet to provide more advice, monitoring and ultimately improved product stewardship in the implementation of facial eczema control plans on farm.