Animal health

Farmers check out Andrea and Thomas Annabells’ heifers at a Smaller Milk and Supply Herds field day held on their property near Hāwera.

Hitting your heifer targets

By Ross Nolly

There are steps farms can take to ensure their heifer calves reach their full potential – and they start with stock movements on and off farm.

Growing heifers that go on to meet their full potential when they join the herd can be a challenge but there are several things a farmer can do to ensure the heifers are well grown and healthy.

A Smaller Milk and Supply Herds field day held late last year at Andrea and Thomas Annabells Hāwera, South Taranaki, farm was designed to help farmers hit their heifer targets.

The field day featured a number of speakers, including Dallas Nelley, a largeanimal vet at Taranaki Veterinary Centre’s Pātea Clinic, who explored the factors that go into producing well-grown heifers.

Nelley spoke about heifer health issues of parasites and farm biosecurity.

Parasite burden is by far the most common problem that Nelley sees on farms. In theory, every farmer should undertake faecal egg counts, but he has performed very few in 25 years of vetting.

He emphasised that farmers must at least have a drench plan, and not just drench whenever they feel like it.

“A quarantine drench should be used on any animal that comes onto a farm. The farmer should do it even if the previous owner has said that they were recently drenched. You need to drench them with something that you know works, so you know it’s been done,” Kelley says.

“You wouldn’t believe how many times I’ve talked to farmers and been told that they’d recently drenched their stock, and it turned out that they’d been drenched six months ago. You must be in control.”

A triple combination oral drench is the ideal quarantine drench, but most farmers tend to use a double pour-on.

“There is now resistance to all of the drench families. You need a thorough

understanding of your system, because eventually it’s going to become an issue for every farmer if they’re not aware of it and know how to manage it.”

“Refugia” refers to a population of parasites in the environment that hasn’t been exposed to anthelmintic drenches. These worms have no drench resistance, and by remaining in the environment (either on the ground or in the animal) they provide a population of worms that are still susceptible to drenches.

“There are many ways of achieving refugia. It can be created by not drenching your best animals, because they don’t need it, due to them having non-resistant worms. Or you can drench them and put them back into the same paddock instead of a new, clean paddock, so they eat the non-resistant worms straight away.”

If you drench stock and put them somewhere clean, the worms that are left (1-2%) and the animal is still carrying, can only breed with the resistant worms. So, you breed the population a great deal faster towards resistance.

“If you drench them and put them somewhere ‘dirty’, or don’t drench some of the animals so some cows have got resistant and non-resistant worms, they’ll breed, and the number of drenchsusceptible larvae will significantly outnumber the drench-resistant population.”

He also highlighted biosecurity as a major animal health issue, saying stock movement is the number one biosecurity risk. Bulls travelling between and onto farms pose one of a farm’s highest biosecurity risks.

“Grazing blocks are very prone to contracting diseases because graziers often receive stock from many farms in many different localities. They also receive bulls. Bulls are often the most disease-ridden animals imaginable, and can carry all manner of diseases,” Nelley says.

He emphasises the need to have a very good relationship with your grazier and to never be afraid to ask them to explain their biosecurity protocols. You must know your bull buyer well and trust them implicitly.

“Here in Taranaki, for example, bulls come here from all over the country, including the South Island. Many have already done a season on a farm. So, unless you run your own bulls you don’t really know their history.

“When the bulls are put in with the heifers, they see many animals at once, so you need a good idea of where they’ve come from. Ideally you should wait three to four weeks before putting them in with the heifers. However, usually the bulls come off the truck and go straight in with them.”

Most farmers are familiar with the disease bovine viral diarrhoea (BVD) and every bull should be tested for it and vaccinated against it.

“We had one case where a farmer lost 35 out of 100 heifer calves because they used a bull that they were told was vaccinated and tested but wasn’t.”

Theileriosis is another disease to be aware of. It’s a disease caused by a species of theileria (a blood-borne parasite) that affects only cattle and is primarily transmitted by ticks. Nelley has tested more positive bulls than negative.

“One farm used cow monitoring boluses and they were constantly getting decreased rumination alerts. It turned out that theileria was going through their herd again. They wouldn’t have known if it wasn’t for the boluses.

“I could give you examples of farms that have lost around 40 cows in a year with theileria. It’s not really heard of a lot, yet it’s quite common in south Taranaki.”

When bulls or any other stock arrive on your property you must remember that it’s your property, and you’re in charge.

Ask your grazier to use the same vet that your farm uses, if at all possible. This gives a continuity of care and everyone, including the vet, knows what’s happening at each property.

Farmers can eradicate some diseases that occur on farm, but not drenchresistant worms. Theileria is the same, says Nelley: “Once it’s on your farm it’s there forever.”

Nelley knows of an instance where a farmer bought one BVD-infected cow from a sale and had to put down 35 heifer replacement calves.

“You don’t hear of those cases because very few farmers want to talk about them.

“About 75% of biosecurity issues are caused by stock movement. Of the other 25%, 12.5% is made up of ‘across the fence’ disease infections. It’s not as big a risk as stock movement, but still a considerable biosecurity threat.” n

“We had one case where a farmer lost 35 out of 100 heifer calves because they used a bull that they were told was vaccinated [against BVD] and tested but wasn’t.” Dallas Nelley

Large animal vet Dallas Nelley says parasite burden is by far the most common problem he sees among cattle.

Under the pump

For tips and ideas, visit farmstrong.co.nz

Sam Whitelock Farmstrong Ambassador

One less piece of paper

By Samantha Tennent

Tweaks to the Welfarm programme will ease the administrative burden on farmers when completing their Animal Wellbeing Plan.

Asimple solution to help farmers complete the animal wellbeing part of their onfarm assessments is now available thanks to a new relationship between WelFarm and Fonterra.

We have just established an automated link that allows us to notify Fonterra when a farm has completed an Animal Wellbeing Plan with its vet through WelFarm, so there is one less piece of paper that Fonterra suppliers need to gather when preparing for their assessment.

And the plans are stored in the WelFarm portal so when farms do want to refer to them, they can easily log in to find it, which saves sifting through emails or requesting another copy from the vet.

The WelFarm Animal Wellbeing Plan template was developed in 2021 in response to the updated requirements from Fonterra for the Co-operative Difference.

We recognised WelFarm was in a unique position already connecting vets and dairy farmers through the wider WelFarm programme, so it made sense to include a simple method to help them develop their Animal Wellbeing Plans and leverage their data further.

The WelFarm programme is a framework for proactive herd health and welfare management for a dairy herd. It has a simple reporting method and provides regional and national benchmarking through the web-based platform that gives context to herd data.

The programme supports the relationship between the dairy farm and veterinarian, helping vets provide tailored advice and support.

If a farm is using the wider programme, some of its metrics feed into the Animal Wellbeing Plan directly, which gives vets and farmers more information to discuss as they develop their plans.

The consistent approach to developing plans is valuable for farmers, Fonterra and the wider sector and using the system gives peace of mind as the template is live and gets updated as Fonterra’s requirements evolve. This saves any back and forth if any updates were missed.

The WelFarm programme is available through a number of vet clinics across New Zealand and more clinics join regularly. We encourage farmers to ask their vet if they are already part of WelFarm or if they would consider joining.

We are also looking at other potential connections to support automatic data sharing to reduce the administrative burden and give farmers even more value from their herd health data. n

MORE:

Talk to your vet about getting your next Animal Wellbeing Plan through the WelFarm portal and find out more at welfarm.co.nz

Who am I?

Samantha Tennent is the general manager of WelFarm

Vets can help farmers with their animal wellbeing plans in on-farm assessments through an automated link that will notify Fonterra of their completion.