Tuesday, 01 November 2016 13:28

Drench resistance is real and growing

Written by 
Drench resistance is already widespread on sheep farms and heading in the same direction wherever cattle are farmed. Drench resistance is already widespread on sheep farms and heading in the same direction wherever cattle are farmed.

Drench resistance is real, already widespread on sheep farms and heading in the same direction wherever cattle are farmed, says Beef and Lamb NZ.

It is embarking on an online campaign to help farmers deal with drench resistance and is providing advice on worm management and how to breed for resistance.

Drench resistance is when worm populations in an animal survive after a correctly applied dose of drench.

The resistant worms then breed, passing their resistant genes on to their offspring.

Over time – if practices remain the same – resistant worms make up an increasing proportion of the farm’s worm population, and then farmers have a problem. As that proportion increases, so does the cost to animal health, productivity and profit.

BLNZ says drench resistance costs money and creates an unfair legacy for future generations.

It advises that it makes sense to keep older, low-cost drugs working as long as possible, because they are much cheaper:

For example, dual-acting drench amounts to 7c-14c/lamb drench, triple-acting drench 20c-35c/lamb drench and Zolvix or Startect, 60c/lamb drench.

“More costly, however, is the effect of continuing to use a drench that is not fully effective. You are wasting time, effort and money.

“The next generation of farmers must be left with drench choices that work.”

BLNZ says most farmers will have resistance on farms long before they start to see a problem.

And then it will often be a major event that makes resistance obvious. For example, a cluster of lamb or calf deaths in late autumn, or a hefty problem with worms in young lambs mid to late lactation.

BLNZ says resistance is widespread in sheep and increasingly widespread in cattle.

A 2006 farm-based survey of 62 North Island beef properties revealed 94% of farms were resistant to at least one drench family. On those farms there was 92% resistance to ivermectin (‘mectin’ drenches), 76% resistance to albendazole (white drenches) and 8% resistance to levamisole (clear drenches).

The survey also found that about 20% of farms showed resistance in at least two worm species; cooperia (intestinal worms) were commonly resistant to ivermectin and albendazole and Ostertagia (brown stomach worm) resistance to ivermectin and levamisole was an emerging issue.

A 2006 survey of 112 NZ sheep farms revealed high levels of drench resistance to all drug families and 25% of farms showed resistance to ivermectin, 24% to levamisole (clear), 41% to albendazole (white) and 8% to a combination drench of albendazole and levamisole.

Specific problems identified were: Ostertagia resistance to all drench treatment options, Cooperia resistance to mectin drenches and Trichostrongylus (black scour worm) resistance to levamisole. All worm species showing a resistance to albendazole.

“In the 10 years since the 2006 survey we haven’t known much about what has happened in sheep,” BLNZ adds. “However, the cattle situation has got worse and we are now seeing resistance in the particularly nasty worm Ostertagia.”

It urges farmers to deal with facts; ideally, in the January-to-May period (when the most worm species are present in lambs), run a faecal egg count reduction tests (FECRT) alongside a larval culture.

“That will tell you how effective your current drench is. Your vet or farm consultant will be able to help you do this,” says BLNZ.

More like this

RMA amendments 'will be a relief to farmers'

The Government’s announcement that a Bill to amend the Resource Management Act (RMA) could be introduced in Parliament next month will be a relief to farmers, says Beef + Lamb New Zealand (B+LNZ).

Winning back farmer trust

One year into her role as Beef + Lamb New Zealand chair, Kate Acland is continuing to work hard and win back farmer trust.

Tough times on farm

Beef + Lamb New Zealand chair Kate Acland says while farmers are quite positive about the new Government, the economic situation on farm is "pretty brutal".

Featured

TV series to combat food waste

Rural banker Rabobank is partnering with Food Rescue Kitchen on a new TV series which airs this weekend that aims to shine a light on the real and growing issues of food waste, food poverty and social isolation in New Zealand.

Celebrating success

The Director General of MPI, Ray Smith says it's important for his department to celebrate the success of a whole range of groups and people around the country.

Biosecurity award for M. bovis work

A small company which mobilised veterinarians around the country to deal with Mycoplasma bovis was one of the winners in this year's Biosecurity Awards, held at Parliament.

Cyclone's devastating legacy

One of the country's top Māori sheep and beef farms is facing a five-year battle to get back to where it was before Cyclone Gabrielle struck just over 14 months ago.

National

Machinery & Products

PM opens new Power Farming facility

Morrinsville based Power Farming Group has launched a flagship New Zealand facility in partnership with global construction manufacturer JCB Construction.

AGTEK and ARGO part ways

After 12 years of representing the Landini and McCormick brands in New Zealand, Bay of Plenty-based AGTEK and the brands’…

100 years of Farmall Tractors

Returning after an enforced break, the Wheat and Wheels Rally will take place on the Lauriston -Barhill Road, North-East of…

» Latest Print Issues Online

The Hound

Cut with care

OPINION: The new government has clearly signalled big cuts across the public service.

Bubble burst!

OPINION: Your canine crusader is not surprised by the recent news that New Zealand plant-based ‘fake meat’ business is in…

» Connect with Rural News

» eNewsletter

Subscribe to our weekly newsletter