Dairy farmers are being urged to plan ahead and breed facial eczema-tolerant cows after New Zealand endured one of the worst FE seasons in years in 2016.
Spore counts ballooned in the North Island and parts of the South Island to the highest in a decade, and many herds had a large number of cows with clinical facial eczema.
CRV Ambreed says orders for straws of semen from bulls with genetics for a tolerance to facial eczema tripled in response in 2016. Tens of thousands of straws were sold and the firm’s global product manager for grazing, Peter van Elzakker, says CRV Ambreed is expecting demand to increase again.
He says bulls from FE teams are 25%-30% less reactive to a facial eczema challenge than the average bull and the latest CRV Ambreed FE bull team, due to be announced in early 2017, is expected to be the best yet.
Research and development completed by CRV Ambreed and its research partners resulted in the ability to identify bulls with improved FE-tolerance. These were first marketed in 2011. Now, about 10% of CRV Ambreed’s 150-strong bull catalogue have increased tolerance to facial eczema, across the Crossbred, Friesian and Jersey categories. Glowing, a Friesian bull who is CRV’s second biggest selling bull, is part of the FE team.
Facial eczema is caused by a toxin (sporisdesim) produced by the spores of the fungus Pithomyces chartarum growing on pasture. The fungus grows in the dead litter at the base of pasture in warm moist conditions, and when ingested by cattle or sheep, damages the liver and bile ducts. It can cause liver failure and death.
NIWA’s forecast for December to February shows most of the country can expect to have average or above average temperatures in this time, and that most of the North Island, plus the west of the South Island, will have normal or above normal rainfall.
CRV Ambreed’s Research and Development Manager Phil Beatson says the genetics approach provides another tool in the toolbox for farmers working in ever-changing environments, particularly in relation to global warming. “Genetic improvement offers a safe, environmentally sound and economical solution. It means less zinc can be used, and farmers can be confident they are breeding long-term solutions for their farms.”
Mr Beatson says global warming will exacerbate the FE problem in New Zealand in years to come. The sheep industry has been breeding for FE-tolerance for years and today’s sheep are now seven times as tolerant to a FE challenge than their 1980s ancestors. But the dairy industry has been slower on the uptake of a genetic solution, he says.
Mr Beatson says it’s estimated that for every three in 100 cows with clinical FE, about 70% of the herd could have subclinical symptoms. “You won’t necessarily see the disease in cows with subclinical symptoms, but it will be damaging the liver and negatively impacting milk production.”
CRV Ambreed is working with AgResearch on a three-year research programme to identify costs associated with lost production, weight loss and death of stock due to FE.