April 23, 2014

New Zealand agricultural history. No 4. Importing exotic sheep breeds

First MAF importation
Selecting sheep for importation
Organising the sheep before transport to New Zealand
Summary of events

By Dr Clive Dalton

 Summary of events
  • Importation date: 1972.
  •  Breeds: Finnish Landrace, East Friesian, Oldenburg (German White Headed Mutton) and Oxford Down.
  •  Where located: Animals selected and purchased (or leased) in UK and Ireland, and mated on their farms of origin.
  • Mode of import:  Purebred pregnant ewes and some rams from UK to maximum quarantine station on Somes Island in Wellington.
  • Multiplication. Imported purebred rams joined with purebred ewes to produce purebred offspring for second lamb crop.
  • Imported purebred ewes then moved to further maximum quarantine on Mana Island, 10 km north of Wellington with balance slaughtered on Somes.  
  •  Romney and Coopworth ewes were taken to Mana to be mated to purebred sires to produce crossbred progeny, each generation increasing the proportion of exotic genes. 
  • Work on Mana continued for 4 years.  
  •  In June 1976, sheep from the expanding flock on Mana were transferred to the Lands and Survey ‘Crater’ block near Rotorua.
  • Routine histopathological monitoring of sheep brains on Mana found Scrapie in one East Friesian ewe in 1974.  Decision made to slaughter all East Friesians, but retain their progeny along with other breeds but extending quarantine another 5 years.
  •   In 1978 continual brain monitoring on Mana sheep confirmed more cases of Scrapie. 
  •  Slaughter of 1900 sheep on Mana and 5192 at Crater ordered in 1978.
  • Release date:  None.  
Selecting sheep for importation
Dr Neil Clarke
Selecting individual sheep as a representative of a breed is never an easy task, as differences within breeds are always greater than differences between breeds. Sadly this is a much-ignored fact in animal breeding.
The task of selecting sheep for the 1972 importation fell to Dr Neil Clarke from the Ruakura Genetics Section. His first job was to find suitable flocks in UK and Ireland that would have sheep for sale, and this Neil said took hours of work from New Zealand by letter and phone calls through our night. The Internet was not firing in the 1970s.

Then when that was sorted, Neil spent over a month in UK and Ireland, along with a Kiwi veterinarian who was the offsider for the NZ Veterinary Liaison Officer resident in the NZ High Commission in London. The vet assigned to Neil had to help inspect flocks that had sheep available with the required performance data, structural soundness, and health clearances to meet NZ standards. 

Neil said it was a full-on job with much evening homework sorting out the day’s data, writing reports and keeping in constant touch with colleagues and bureaucrats back in New Zealand. This was all during the UK night of course.

Neil said that he could have well done without his vet mate in the evenings when he had work to do, as the Kiwi vet was clearly relishing the chance to get out of London on to farms, and sample local hospitality at NZ government expense.   After the northern hemisphere sun went down well before 5pm and it was rising in NZ, it was time for Neil to start his night shift!

Organising the sheep before transport to New Zealand
Neil Clarke remembers this as a massive job although he had left for New Zealand before it started.  The ewes had to be assembled at one location in Ireland and at the Farmers' Weekly farm in UK, to be treated with the required hormones to get them all into a similar breeding cycle to be mated to lamb within a limited spread in NZ.   

This involved a massive input involving hormone treatment protocols, and he reckons that without the enormous assistance from Dr Seamus Hanrahan of the Irish Dept of Agriculture who was a master at getting top results, the show could never have got on the road to meet all the deadlines.

Then there was the genetics to sort out to avoid close matings, and ensure the genetic base of each breed was as wide as possible to maximise breeding potential for their future in New Zealand.

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