The team tested a number of common New Zealand sheep breeds including the Coopworth, Romney and Corriedale and found that they already had high levels of the resistant “ARR genotype” which the British rate as most resistant to scrapie under their National Scrapie Plan.
“What was notable about our research was that New Zealand sheep populations still carry the resistant genotype despite New Zealand being scrapie free and this gives us a head start on introducing these genetics into our sheep should scrapie ever occur here,” said Dr Hickford.
Being scrapie free gives New Zealand the benefit of having access to overseas markets for its meat and sheep genetics, plus also better animal health and welfare, given the neurodegenerative effects of this disease.
Variation in the genotype frequencies in the New Zealand sheep population was very similar to that found in sheep populations all over the world with all the different variants forms of the scrapie susceptibility or PRNP gene, including the most scrapie resistant and scrapie susceptible variants.
“As there has been no scrapie in New Zealand to put selection pressure on the PRNP gene, it might have been expected that the resistant genotypes would be less common or not present at all,” he said.
“This suggests that the gene is associated with things other than just scrapie, said Dr Hickford, “but we can only guess what they might be at this point.”
“Some people, of course, will remember that New Zealand has had two scrapie outbreaks in imported sheep in the past; the first in South Canterbury in 1951-1954 and the second on Mana Island in 1978. In both cases the disease was completely eradicated and no traces of it remain,” said Dr Hickford.
The Gene-Marker Laboratory at Lincoln University undertakes scrapie genotype testing for farmers nationally and internationally.
“Let’s hope that we never see this disease again,” said Dr Hickford, “but if we do then we are prepared for it”.
FOR FURTHER INFORMATION CONTACT
Janette Busch
Technical Writer
Agriculture and Life Sciences Division
Lincoln University
Canterbury
Phone: +64 3 325 2811
About the Agriculture and Life Sciences Division
Agriculture and Life Sciences is Lincoln University’s second-largest division, providing teaching and research in a number of areas including: Animal Science, Farm Management, Horticultural Management; and Food and Wine Science. It has a number of specialised research units including the Centre for Soil and Environmental Quality; Centre for Viticulture and Oenology; and Centre for Advanced Computational Solutions. The Division operates its own vineyard, horticultural research area, winery and nursery, and has three research farms.