New Zealand animal health. Concerns over use in dairy farming.

By Dr Clive Dalton

           

When Britain’s chief medical officer, Dame Sally Davies warns that the increasing resistance of bacteria to the most powerful antibiotics available equals the threat of terrorism and climate change to the UK public, then dairy farmers in New Zealand need to take notice – and action.  She describes it as catastrophic, setting human health back 200 years.

The UK chief pharmacist says progress has been made in hospitals and by GPs to cut down risks of increasing resistance, but antibiotic use has been rising in animal and fish husbandry, and this is thought to account for 50% of antibiotics used in UK where overall bacterial resistance in humans is increasing.

As a major exporting nation, especially to Europe and America where they have started to tighten up antibiotic use, we need to follow suit with a vengeance – but there’s little sign of it.

Just count all cows that have been dried off this season using ‘blanket’ Dry Cow Therapy (DCT), where the whole herd gets a tube of antibiotic up each teat whether they need it or not.  It’s a major money earner for vet practices at around $25/cow.

DCT is part of current best practice under SmartSAMM, which is the new version of the old SAMM Plan or ‘Seasonal Approach to Managing Mastitis’. Kiwi GPs I have talked to have never heard of DCT.

We’ve had a Mastitis Advisory Committee of the country’s experts for over 30 years, and it seems to me that all this has achieved is more antibiotics used in dairying and not less.

The trouble is that when a new wonder drug appears, as happened with anthelmintics to kill worms as well as antibiotics, everybody makes money – the manufacturers, veterinarians, sellers of the products and farmers. 

Nobody dare say – hang on a minute, how long will this bonanza last before some of the enemy survives the bombardment and continue breeding?  Some brave folk questioned worm drenches 40 years ago but got rubbished. No new antibiotics have been developed since 1987.

When at the Waikato Polytech, I tried to convince my dairy students that the industry was not about hooning on bikes, spraying weeds, hosing effluent and slapping cups on teats.  I tried to stress that it was the ‘neutraceutical’ or human (especially infant) health food business.  I totally failed.  My sermons were greeted with ripe expletives, especially after they’d been back home and told their bosses.

I had 11 different empty packs of DCT and we visited vet clinics to talk to the chief veterinarian about how they approved what farmer should use.  When we left, students joked that their bosses regularly bought the cheapest, which they had to administer while under pressure at the last milking.  So cutting corners on the textbook asceptic practice was inevitable.

Boffins are not keen to look ahead if the road seems too difficult – and it’s worse now the way research is funded.  Most don’t think of issues beyond their retirement age, and ignore future generational problems and biological time.  If they did, how come we have serious drench resistant worms after only 50 years, and complete ignorance of what happens when anthelmintic chemicals and antibiotics get into the soil?

Kiwi boffins after reading papers at International conferences return to report that New Zealand is up with ‘the world’s best practice’ in mastitis control.  How pathetic is that?  As a country that lives or dies by exports to an increasingly sophisticated market, we shouldn’t be up with them; we should be light years ahead!

Then we skite about only 11% mastitis in our national herd compared with around 25% in the US.  That’s another daft comfort blanket, as our 11% is achieved by using all the antibiotic weapons in the current SmartSAMM arsenal. SmartSAMM is grossly out of date!

The other defence is that there’s no peer-reviewed evidence showing major antibiotic resistance in mastitis bugs currently found in New Zealand.  Yeagh Right - but who is looking?

This won’t do in 2013.  If current researchers and experts can’t deal with the urgent need to reduce antibiotics in the dairy industry, then let’s find some who can. We need to go back to the calf in utero to find out what is stuffing up the development of its natural immune system – something is.  And what about genetics?  They seem to have low priority in veterinary training.

If there isn’t rapid change on Kiwi dairy farms, then our customers pushing their trolleys around the supermarkets of the world, especially those shopping for baby formula, will bring about change.

Food concerns have changed dramatically in the last 3 years.  Just mention ‘Chinese infant formula’!  Blanket DCT would be the last thing they’d appreciate, and the acronym DCT could cause even bigger panic than DCD.

However, there’s a small and increasing number of dairy farmers, especially women, getting antibiotics out of their dairies.  But they’re keeping well below the parapet to avoid pressure from their dairy companies and veterinarians, suggesting that whatever they are using cannot work, hasn’t been approved, and avoiding antibiotics will compromise animal welfare.

Those overseas supermarket trolleys will have the last say, when they roll right on past the NZ dairy product displays.