Ded­i­ca­tion reaps re­sults

Matamata Chronicle - - Rural Delivery - By DR CLIVE DAL­TON

FOR MORE than half a cen­tury fa­cial eczema has caused mas­sive an­i­mal suf­fer­ing and eco­nomic loss to Waikato flocks and herds, and ev­ery year it still takes its toll. Find­ing the cause and pre­ven­tion mea­sures took 30 years of re­search by ded­i­cated Ruakura sci­en­tists work­ing with farm­ers.

In fact, it was farmer ac­tion led by F C (Togo) John­stone and Fed­er­ated Farm­ers that got Dr C P McMeekan out of Massey Univer­sity to head the Ruakura An­i­mal Re­search Sta­tion, to find a so­lu­tion to the scourge caus­ing mas­sive eco­nomic losses on Waikato farms.

When I ar­rived at the Whatawhata Hill Coun­try Re­search Sta­tion in 1968 re­searchers had done all the hard work and treating an­i­mals with zinc salts was the known pre­ven­tion. This was easy for dairy farm­ers but not for hill coun­try sheep farm­ers where weekly drench­ing with zinc ox­ide was just not prac­ti­cal.

Be­cause farm­ers no­ticed that some sheep sur­vived what­ever the sea­son re­searchers started a flock se­lected for high fa­cial eczema re­sis­tance, pos­si­ble as the toxin had been iso­lated from the fun­gus grown at Ruakura, so sheep could be dosed with it to mea­sure their liver re­ac­tion. Fa­cial eczema re­sis­tance was clearly in­her­i­ta­ble and quite strong too, so this al­lowed farm­ers to start se­lect­ing for it along with their other pro­duc­tion traits.

And they did – with great en­thu­si­asm and suc­cess, work­ing closely with Ruakura staff.

A ma­jor driv­ing force in this was the late Colin Southey, a Min­istry of Agri­cul­ture and Fish­eries farm ad­viser at Pukekohe, along with for­mer All Black captain Andy Dal­ton. In their Raglan coastal hill coun­try area in the early 1970s, fa­cial eczema was killing 40 per cent of flock re­place­ment hoggets, caus­ing enor­mous eco­nomic loss to hill coun­try farm­ers. Many farms were los­ing 1000 sheep ev­ery year.

It was Mr Southey who drove the Ruakura lab test­ing into wool­sheds for vets to ad­min­is­ter the toxin and mea­sure the re­sponse in blood tests. Farm­ers put up their top two-tooth rams and only kept those that sur­vived the in­creas­ing lev­els of toxin as the years went on.

Dose rate de­pended on weight, so in the early days this was 0.1-0.2mg of sporidesmin/kg of live weight but most Waikato sheep breed­ers have sheep that will now take 0.6mg. In these flocks, even in se­vere years, they now never see a clin­i­cal case of fa­cial eczema so the pro­gramme has been a mas­sive suc­cess.

But the dis­ap­point­ing fea­ture to me was that after 40 years of hard work and in­vest­ment, none of the Rom­ney, Coop­worth or Peren­dale breed­ers got rich sell­ing their fa­cial eczema-re­sis­tant rams.

The main rea­son was com­pla­cency as fa­cial eczema was never se­vere ev­ery year. After a bad year, panic drove com­mer­cial farm­ers to buy re­sis­tant rams but then, as they didn’t see the im­pact for some years, they con­cluded that noth­ing had worked.

In the early days few farm­ers kept buy­ing fa­cial eczemare­sis­tant rams reg­u­larly. They didn’t un­der­stand that ge­netic change took time, es­pe­cially as it was only en­ter­ing the flock on the ram side – it was too ex­pen­sive to test ewes. Selec­tion on the fe­male side had to come through ‘‘sur­vival of the fittest’’ which was very costly. The other frus­tra­tion was that even after mas­sive losses, too many Waikato sheep farm­ers were loath to buy rams lo­cally, stay­ing with their reg­u­lar sup­pli­ers fur­ther down the North Is­land where fa­cial eczema had never been seen.

They also sourced re­place­ment fe­males from these ar­eas, which was ge­net­i­cally dis­as­trous as this can­celled any ge­netic gain made by the rams.

Stock agents also had a big part to play in this mis­guided prac­tice, as many I bat­tled with reck­oned Raglan hill coun­try rams were ‘‘too blardy small’’ but I al­ways sus­pected there were com­pany deals to move sur­plus big fat Wairarapa rams with great eye ap­peal up to the Waikato.

It was good busi­ness for the agents, as the rams didn’t live long and they got reg­u­lar busi­ness each sea­son.

But things have changed, es­pe­cially in the last five years, with this year see­ing a to­tal clear­ance of breed­ers’ fa­cial eczema-re­sis­tant rams, mainly due to in­creas­ing dry sea­sons and the ap­pear­ance of fa­cial eczema in new ar­eas such as the North Is­land East Coast and Wairarapa.

The sheep in­dus­try should be grate­ful to these Waikato breed­ers of fa­cial eczemare­sis­tant sheep who never gave up and were pre­pared to in­vest in on­farm re­search and de­vel­op­ment to deal to a ma­jor an­i­mal scourge. They proved that to farm sus­tain­ably to­day, ge­net­ics will have a bet­ter long-term out­come than chemo­ther­apy.

Aside from this and last week, it would be easy to as­sume spring had ar­rived early in the Waikato but be pre­pared for late chills and con­sider the fol­low­ing:

Too many small farm­ers start their lamb­ing and calv­ing too early, and be­fore pas­tures re­ally get go­ing so they run out of feed after the first win­ter-saved pas­ture has been eaten.

If you’ve made good qual­ity sup­ple­ments, make sure you feed them to stock that most need it. Poor sup­ple­ments cost just as much to make as good ones.

To­day’s sheep breeds are all ca­pa­ble of lamb­ing mul­ti­ples, so man­age thin ewes through lamb­ing and early lac­ta­tion. Make sure all lambs are get­ting a good feed each day.

If you didn’t vac­ci­nate ewes prelamb­ing, check with the vet what vac­cines you should give the lambs for your prop­erty. Pulpy kid­ney vac­cine is an im­por­tant one. Ewes should not need a lon­gact­ing worm drench be­fore lamb­ing and never drench young lambs at dock­ing. Don’t dock lambs’ tails too short, they should have enough tail to wag.

The main con­cern is to keep the feed up to cows suck­ling calves, as you will want them to start cycling and get in calf, 6-8 weeks after calv­ing.

De­horn and cas­trate calves be­fore six weeks old, us­ing an anaes­thetic.

Dr Clive Dal­ton is a for­mer agri­cul­tural sci­en­tist and now tech­ni­cal ed­i­tor of­ Email: clive@lifestyle­

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