with Phil Rennie
Research has thrown up the common pit falls of facial eczema control in New Zealand. The DairyNZ-funded study conducted in 2015 raised a number of key points as noted below. It was led by Waikato veterinarian Emma Cuttance.
Sub-clinical facial eczema – or FE – is a problem on at least one-third of dairy farms in the North Island, where the Bay of Plenty would be no exception.
Spore counting, caused by fungus Pithomyces chartarum, 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 FE season.
Chicory and plantain, planted in pure swards, protect against FE, 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 water is the most common method but the least effective at achieving adequate zinc levels in cattle. 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 cattle have control over their 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 control efforts are providing adequate protection.
Your local vet clinic can provide you with monitoring and treatment options suitable for your property to provide the best possible protection against facial eczema this autumn.