The B+LNZ CPT programme has helped raise the genetic performance of the national flock since it was introduced by Alliance Group in 2002. Progeny testing is the comparison of sires on performance of their progeny – effectively proof of genetic merit.
To date, sites for the CPT in Hawke’s Bay, Canterbury and Southland have been on relatively flat and low country. Now two hill sites, one in the North Island and another in the South Island, have been included through matings this year.
The new South Island CPT site is at Onslow View in Otago hill country, while the North Island site is at Koromiko, a Taratahi Agricultural Training College farm near Masterton in the Wairarapa.
The location of the properties is essential to address concerns some in the industry have about whether the top sires based on progeny performance on low-country will also be the top sires based on their progeny performance on hill country.
There is an opportunity to look at differences between hill country and lowland performance and inform farmers about the need to have different selection objectives for animals run in the different environments.
Alliance Group livestock general manager Murray Behrent said the addition of the hill sites was an exciting development.
“With a significant number of sheep farming properties on hill country, it is essential to investigate further whether the ranking of rams changes depending on the environment.
“This is very important research for the sheep industry. The extent to which ratings for genetic merit are applicable across different environments needs to be quantified before we can decide how best to deal with such effects.”
The new sites have been established as a lead into the establishment of B+LNZ Genetics, the new entity that will include the activities of SIL, farmer levy investment in the B+LNZ CPT, and Ovita. Ovita was the partnership between BLNZ, AgResearch and government to fund research into sheep genomics.
Eleanor Linscott, of Ovita, said: “DNA tools will be critical to the future improvement of maternal traits in sheep and the hill environment is a key part of NZ sheep agriculture.”
Both new Central Progeny Test sites are run as commercial farms rather than research stations and will focus on measurement of maternal traits including ewe fertility, lamb survival and ewe longevity.
Linscott said matings were by artificial insemination so that the same dual-purpose rams were used on both hill and lowland CPT sites.
DNA parentage testing and RFID tagging are being used to determine parentage of lambs and ensure that performance of individual progeny can be measured. Alliance Group has recognised the value this development will deliver and contributed to the establishment phase for these hill sites.
“In order to evaluate the maternal performance of a ram, ewe progeny have to be retained until they reach breeding age and then their performance measured and recorded for a number of years,” Linscott said.
The CPT focuses on identifying the best genetics regardless of breed. About 260 rams from several breeds have been evaluated to date to improve genetic connections within the NZ sheep industry. The key objective is to identify the sources of high-performing rams by extending and strengthening comparisons across flocks and breeding groups. The CPT is also developing genetic parameters and industry understanding of novel traits. Work is also under way on fostering links between ram breeding groups and providing a genetic resource for add-on projects of value to sheep farmers and allied industries.
– Supplied
