We’ve been hearing a lot about biosecurity lately. There’s been the kiwifruit Psa-V bacteria, myrtle rust, the Queensland fruit fly, Varroa mite, kauri dieback disease and, of particular concern to farmers, Mycoplasma bovis (M. bovis). The threats keep coming and with them, risks to New Zealand’s economy.


Billy and Sharn Roskam (pictured above with dog Camo) say biosecurity is like wearing a seat belt – it quickly becomes second nature.
Long before M. bovis became a problem here, the Roskams were practising farm border control. They say it’s not been hard or expensive to do.
“We believe a good biosecurity routine is always essential – not just when there's a major disease to worry about,” says Billy. “If you work on a farm or have contact with farm animals, everyone can play a part in making sure good hygiene practices are in place.
“Before the arrival of M. bovis, we’d already put up better fencing along our boundaries to protect us from incursions of bovine viral diarrhoea (BVD). And we’re planning to double-fence all our boundaries and plant evergreen trees to create a hedge in the future. The trees will serve two purposes: they’ll offer protection and provide us with a steady source of firewood,” says Sharn.
Comings and goings
Biosecurity signs are the first line of defence against infections coming onto the Roskams’ farm. These are backed up with a parking area, a sign-in process and a boot-washing station. Staff who aren’t based on the farm leave their boots there – another simple step to help minimise the risk of transferring diseases and pests between farms.
If truck drivers are delivering something and not moving beyond the tanker track, Sharn and Billy aren’t too worried about them bringing disease onto the farm.
“However, everyone has to use the footbath and the stock crate has to be clean,” says Sharn.
The farm’s bobby calf collection area is separated from the heifer-raising area and features its own boot-washing station.
“We have a separate and fully-enclosed shed where the truck driver collects the bobbies. It is completely independent from the bobby-raising and heifer-raising facilities,” says Billy.
“We have a runoff, and if we’re transporting animals from the farm to the runoff, the crate has to be cleaned so we know we’re dealing with a clean slate, so to speak. This isn't always possible, so we quiz the drivers about where they’ve been. Contractors generally clean their equipment between farm visits and I hope they keep that practice up.”


Keeping their boots clean are vet technician Stephanie Allison and vet Elena Knupfer, both from Vetsouth Winton.
Staying weed-free
The Roskams protect their farm from troublesome weeds by being fully self-contained – they import no feed onto the property.
“We grow kale and fodder beet for winter feed and any grass seed we buy is from accredited suppliers. It may be a little bit more expensive, but it’s worth it for the security of knowing that it’s weed-free,” says Sharn.
Staff on board with biosecurity
Sharn and Billy’s team of four staff are aware of the farm’s biosecurity policies, and don’t need to be reminded.
“Our staff genuinely have an affinity for the stock and care about them, but of course if we don’t have a herd, they don’t have a job. But all jokes aside, the team would be gutted if any of our stock got sick,” says Sharn.
“We don’t have to crack the whip. They’re very good at topping up the disinfectant baths and making sure the cleaning brushes are there, looking after the boundaries and that sort of thing. It’s become the norm. It’s like wearing a helmet or a seat belt – you have to consciously remember at first, then it becomes second nature.”


Sharn Roskam (pictured) and husband Billy describe their farm as a castle whose borders must be protected at all costs.
Pest control
Farm owner Mara Blackwell runs a rigorous possum and rat control programme, with eight bait stations around the farm and rat and mouse traps around the buildings. Pigeons and hares, which have also been identified as pests, provide target practice for Billy and the locals.
“Someone came in to shoot hares and got 68 one night. I take care of the pigeons, but not near the sheds because we don’t want to fill them (the sheds) with holes,” says Billy.
Accidents can happen
The Roskams recently had a biosecurity breach over a 48-hour period. It started on a Thursday, when Sharn went to check the stock at the runoff, which has a double-fenced drain between it and the neighbour’s boundary.
“The girls were all happy sitting down and looked at me as if to say ‘what are you doing here?’ When I went back again at lunchtime on Saturday, the yearlings were all at the top of the paddock having a good yarn with seven or eight white faced beefies,” says Sharn.
“Somehow, the neighbour’s stock had got in and were jammed up between our fence and the end of the drain on a small piece of grass. I wondered what we were going to do.”
Sharn rang the neighbour and asked them if they were aware of the health status of their animals. Were they free of BVD and M. bovis? Because the farm manager was away, Sharn couldn’t get answers so she contacted her vet, Briar Cooper, from Vetsouth Winton.
“I told the vet what had happened. There was nothing we could do if there was an M. bovis problem, but we could do something about BVD. Briar said we had only a couple of options: we could get the neighbour’s stock in to blood-test them for BVD, or we could vaccinate our stock immediately and then again in three weeks’ time.
“The concern was that it may not be sorted by the time mating started. So we decided to vaccinate, and if any of them got BVD through the fence, a vaccination programme would stop the others from getting it. So $600 to $700 and a couple of yardings later, we hope we’ve got it sorted.
“You can think you’re doing the right thing but even with a double fence, accidents can happen. You need to be ready for the worst, and prepared to act fast if something does go wrong,” says Sharn.


As well as double-fencing all their boundaries, Sharn and Billy are planning to create evergreen hedges to provide extra protection in future.
Keeping up to date
Billy and Sharn keep an eye out for new information, act on it and implement different things.
“We don’t necessarily have to spend money. Most of the stuff we have for biosecurity has been free. We went to an MPI (Ministry for Primary Industries) meeting in Winton and they gave us some signs, but we’ve also had signs made for the tanker track and for certain entry/exit points on the farm and the runoff,” says Billy.
“You can easily make footbaths out of used containers,” says Sharn, “The only major thing I’ve bought was a long-handled brush for scrubbing boots. I splashed out $25 for that.”
Using DairyNZ resources
Billy and Sharn have used DairyNZ’s Biosecurity WOF (Warrant of Fitness) checklist to help them identify ways to protect their farm. They are also considering changing mating management this season and are using the M. bovis information on the DairyNZ website to look at the pros and cons. They also attend M. bovis meetings and are grateful to have proactive vets.
Two simple tools to manage biosecurity on-farm
On-farm biosecurity doesn’t have to be expensive or take up much time – but it will make a difference. These DairyNZ tools below are a great way to get started.
Pre-Purchase Checklist
Bringing new stock onto your property presents the risk of M. bovis and other diseases infecting the stock you already own. You can identify and manage many risks using DairyNZ’s Pre-Purchase Checklist. This checklist provides some simple questions you can ask to determine the health status and history of stock (any age or class) before you buy them. Download the Pre-Purchase Checklist here.
Biosecurity WOF
DairyNZ’s Biosecurity WOF helps you identify and manage a range of biosecurity risks on-farm in simple and practical ways. Download the Biosecurity WOF here.


Stephanie and Billy discuss a dry cow therapy trial and decide which cows to draft for milk sampling.
Words: Christine Hartley Photos: James Jubb
This article was originally published in Inside Dairy November 2018