She found a lot of unseen damage farmers didn’t know about.
Generally, it was thought there wasn’t a lot of FE seen last season.
However, the study found there was substantial damage, even in herds using prevention.
Cuttance found 41% of the cows were affected by FE despite only 3% showing symptoms.
That shows just because farmers can’t see it, doesn’t mean it’s not happening.
She also measured the impact this had on loss of production by comparing the average amount of milk collected from healthy cows and cows with FE. She found cows with liver damage produced about 8% less milk.
Another study also measured the impact of FE on young stock growth.
It found 19% of the 1050 heifer replacements at 17 various locations had severe liver damage. Another 21% had some liver damage.
Damaged animals were 15kg lighter on average at first calving compared to their peers. That can have a long-lasting impact including lower in-calf rates, later calving and lower milksolids yields.
Waikato dairy farmer Gavin Fleming and his family have battled FE on their Otorohanga farm for the past 50 years.
Gavin says for as long as he can remember FE has been a challenge on the farm his father bought 62 years ago, some years worse than others.
He puts that down to the farm’s north-facing position. North facing areas tend to have higher spore counts than south facing.
However, over the last five years he and his son Paul have really managed to get on top of the disease.
Until then, despite following best practice, closely monitoring pasture spore counts and regularly drenching zinc, the pair struggled to prevent the disease.
Determined to get to the root of the problem they did some research and worked with their local vets, who ran blood tests which revealed the issue.
They discovered they had been under dosing zinc.
“It just goes to show it’s critical to get your levels right,” Fleming says.
“We drench our milking herd daily to keep their zinc levels up.”
However, Fleming finds zinc bullets, which slowly release a consistent dose, a more practical option for their young stock.
His key advice for farmers is to be vigilant about monitoring spore counts.
The farm was one monitored in the FE study that found none of the cows sustained any liver damage.
Fleming says it was great to be a part of the study and get confirmation that everything they are doing is right.
Like many farmers he can’t wait to see what developments lie ahead to prevent the disease.
“I’d really love LIC to breed some FE-resistant bulls. Over time, I’m sure it will happen. Until then we’re stuck with trying to prevent it.”
