This comes as the industry pushes to register a zinc oxide bolus in Australia in a bid to provide farmers with the most accurate way to administer the supplement, which deters facial eczema.
For years, the dairy industry has successfully supplemented milking herds with zinc oxide, to prevent facial eczema, by adding it to rations fed in the bail during milking.
There is no cure for facial eczema, a disease that causes liver damage in livestock, resulting in a loss of appetite, weight and milk production and which can lead photosensitisation of exposed skin where it becomes sensitive to sunlight, with burns and blisters.
Facial eczema is caused by livestock consuming a fungal toxin in perennial ryegrass pastures and is more prevalent during certain seasonal conditions and areas.
Animals that survive facial eczema often suffer permanent liver damage, never fully recover and require culling, according to Dairy Australia.
Dairy Australia animal heath and fertility program leader Kathryn Davis said there was an “elevated risk” for facial eczema this season, a forecast based on regular pasture samples from farms across Gippsland and the Bega area.
In a program run by Dairy Australia, the samples begin to be collected in January and provide an indication of the risk in these areas by measuring spore counts at the base of a ryegrass plant. If spore counts rise to dangerous levels, Dairy Australia issues an alert to farmers. Dr Davis said farmers had been working quickly and had ordered zinc oxide to be mixed with feed a few weeks ago before the risk for facial eczema elevated with a rise in pasture spore counts. She encouraged farmers to speak to their vet or stockfeed company.
Feedworks ruminant business manager Ian Sawyer said young and dry dairy stock, beef and sheep could be supplemented with zinc oxide via a 10mm nut trail fed in the paddock or through a regulated intake through water supplies.
He recommended against feeding the supplement through a self-feeder to avoid “dominant” animals eating more than their daily requirement. The size of the nut also allowed for it to be eaten from the ground by animals.
Feedworks submitted a dossier to the Australian Pesticides and Veterinary Medicines Authority in 2014 — the last season with a high pasture spore count — in an attempt to register the zinc oxide bolus in Australia.
Widely used in New Zealand, the bolus goes into the rumen of an animal and slowly releases the zinc oxide.
The dossier included data from across the Tasman, but the registration application was unsuccessful due to the requirement for more information.
Mr Sawyer said the industry would work further with New Zealand to generate the additional data required by AMPVA and said he hoped the bolus could be registered this calendar year.
By: SIMONE SMITH
Source: The Weekly Times