April 23, 2014

New Zealand agricultural history. No 15. Importing exotic sheep breeds

Dr Neil Clarke's ideas on genetic multiplication
MAFTech technical support at Hopuhopu quarantine station
Visits to Hopuhopu
Diseases - Ovine Johnes Disease (OJD)

By Dr Clive Dalton

Hopuhopu quarantine station - Dr Neil Clarke’s genetic ideas
Dr Neil Clarke's office and files
Dr Neil Clarke told me about the endless internal reports he produced and that were hammered out on Genetic section’s latest golf-ball typewriter by their very-understanding typist Garthia Flight, and which must be all now in some big black MPI or National Archive hole in Wellington.  Fortunately Neil has carbon copies in his home office in cardboard boxes.

In one internal 1985 report, after the embryos were inside recipient ewes on Somes Island, Neil presented his views suggesting multiplying the purebred offspring to become purebred ‘nucleus flocks’ of the three breeds, and in addition he recommended building a bank of frozen semen and embryos for release to industry at the end of quarantine. A bank of semen and embryos was a brilliant idea, and would have cost little, but it never happened.  It would have been invaluable when (and not if) we get Foot and Mouth disease to restock our sheep.

Neil also suggested in his report that crossbreds should be generated at Hopuhopu to compare the breeds under commercial conditions, as well as getting commercial information from breeds released as frozen semen in a sire reference scheme.  His report was strong on recommending that this be done in flocks of cooperating breeders that were on Sheeplan, where performance was automatically recorded and analysed.
Well, none of this happened but plenty of other things did.

MAFTech Technical support at Hopuhopu
Ian Malthus, a Technical Officer at the MAF Woodlands Research Station near Invercargill, was asked to move to Hopuhopu and help set up the facilities to quarantine the sheep from Somes, including the embryo transfer work to multiply the purebreds, and then supervise the production and multiplication of the resulting crossbreds from the exotic purebred rams.

Dr Robin Tervit who had moved on from MAFTech to join a commercial company (Genestock) remembers that the Hopuhopu hormone regimes for the ET work was done by Jeremy Thompson, with technical help from Robyn Shankey, Glenys Parton and veterinary supervision by Barry Smith.
 Dr John Smith from Ruakura may also have been involved in the ET work.

Ian thinks that around 150 purebred lambs arrived at Hopuhopu from Somes at weaning in 1985. They lived in the woolshed for several weeks with daily outings onto grass, taking some 3 weeks for them to learn to eat grass and 7 weeks to adjust to their new diet.

Visits to Hopuhopu
Converting the property into an efficient primary quarantine station that met all specifications was a big job, as the farm had to be double fenced with deer netting to meet the requirements of MAF Animal Health Division and the Maximum Security Quarantine Advisory Committee (MSQAC).  Facilities had also to be built for visitors and veterinarians who had to be present every time a service vehicle left the premises to supervise its cleaning, and for a regular twice a week inspection of the stock.  There were around 7 farm staff on the farm.

Peter Hoyle
I managed to sneak a look at the Hopuhopu sheep with our Hamilton MAF vet Peter Hoyle who had the main local supervisory role.  Getting into and out of the place was an interesting exercise, as you had to change into MAF overalls and gumboots, and then walk through disinfectant, then through a double gate system. 

On the way out you did the same, changed back into your clothes. Later all staff and visitors had to shower when exiting.  There was no separate area for the ladies who took turns with the men in the showers!  I hope that meaning is clear!

Goodness knows what nasties we were supposed to take in or bring out of Hophopu, but it was a good discipline for everybody and made you think about the importance of biosecurity to New Zealand’s economic survival.

Disease concerns 
Roy Sproule

Hamilton MAFQual veterinarian Roy Sproule assisted his colleague Peter Hoyle, who had overall supervisory responsibility for the station  in their regular weekly inspections.

Roy recalls much wailing and gnashing of teeth over veterinary requirements, when sourcing the ewes to become dams of crossbreds at Hopuhopu after mating to the exotics, and which would be the main sale items for the industry through Sheepac.   

Freedom from Ovine Johnes Disease (OJD) (which is different from Bovine Johnes Disease) was the main concern as it was a ‘notifiable’ disease so had to be taken seriously. The trouble was that few if any sheep farmers would have seen cases, and would certainly never have tested for it.

Ken Jury
 Ruakura Director the late Ken Jury got fed up with all the veterinary quibbling over OJD, which wasn't surprising because Ken was a man who didn't like 'stuffing about'!  Ken liked action.

John Dobbie remembers coming up with a plan to go back through the Romney Association flock books for 20 years to find the studs that had sold most rams used for single-sire mating. 

He also went to breeders in Group Breeding Schemes with similar long histories of selling stud sires. From a chosen 6-8 flocks, John remembers then getting breeders’ permission to test for Johnes, and then MAFTech paid a premium for 30 two-tooths, 30 four-tooths and 30 six-tooths from each flock.

Nobody can remember where the Coopworth ewes came from to go to Hopuhopu for MAFTech at this stage, or how they were chosen. They were not part of Sheepac investors at this stage. Any information would be welcome on this.

John Dobbie also remembers an interesting bit of sheep behaviour causing problems with the exotic rams in their mating preferences for certain ewes.    If an exotic breed ram had to mate a group of mixed breeds, he invariably mated his own breed of ewes first, so John had to be one ahead and offer an exotic breed ram some Romneys before he saw or smelled any of his own kind!  
This was a fairly new observation with British and European breeds but was common in Merinos.

Unlike the disaster of the fist importation, all the MAF staff involved in the second import had the great satisfaction of seeing the job  completed and was well done.  Thankfully Scrapie has never appeared in the years following release of these sheep.

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