Partnership hopes for predictable breeding

Press, 30 December 1988, Page 9

Partnership hopes for predictable breeding

Finding animals that have a predictable influence on a flock’s wool production is the aim of a recently established breeding and research partnership between MAFTech South and Mt Linton Station, situated near Fiordland in Southland. MAFTech South sheep breeding consultant, Mr Randal Rummel said that both organisations had spent several years looking for sheep that could significantly influence fleece weight. “By combining the two genetic resources that have been built up over that time, and conducting a collaborative research programme, this process can only be enhanced,” he said. There was a much better chance of identifying animals with unique genetic merit. In 1983 Mt Linton and MAFTech screened large numbers of Romney hoggets and set up elite high fleece weight flocks. In both instances, subsequent advances in the fleece weights of offspring from the mating of elite ewes with elite rams had been spectacular. In terms of genetic progress, the screened flocks had leap-frogged at least two generations of conventional selection, indicating that the animals possess specific genetic qualities. The presence of a single high fleece weight gene has been suggested and is the subject of continuing investigations. If the single gene exists, the trait for high wool production could be easily transferred to other sheep and other breeds in the same way that prolificacy in Booroolas and medullated wool in Drysdales are transferred by way of single genes. Mr Rummel said while it was not known yet whether the sheep possessed a single high fleece weight gene, it was known

that they did provide substantial increases in wool production, and such animals could only be of benefit to the industry. A limited number of ram hoggets from the programme have already been sold privately to commercial farmers. The animals had justified their high fleece weight tag and provided further evidence that the research programme was heading in the right direction.

The owner of Mt Linton station, Mr Alastair McGregor, said enough proven progress had been made to confidently sell animals knowing they would perform. Based on scientific principles and selection procedures New Zealand’s sheep industry had an exciting future, he said. Mr McGregor’s enthusiasm for improving the performance of sheep, particularly Romneys, stems from a long association with the breed. His grandfather registered Mt Linton’s first Romney stud in 1907 and this was continued by successive generations of McGregors until 1975. At that time the stud was disbanded because it was felt that more progress could be made by selecting within the station’s large unregistered flock rather than by persevering with the small registered flocks. In 1976 almost 14,000 twinning two-tooths from Mt Linton were screened to form the basis of the “Tan Bar” high fertility easy care flock. The Tan Bar flock is run in the natural environment that characterises the Mt Linton run, and now numbers 1500 ewes, 600 ewe hoggets and 600 ram hoggets.

Situated on the lower slopes of Southland’s Takitimu mountains, the 10,117 hectare property carries 65,000 breeding ewes, 20,000 ewe hoggets, 1500 Angus and Hereford breeding cows, 900 fatten-

ing cattle, and 300 red deer. Climatically winters are cold with heavy frosts and some snow. For three months of the year there is no growth at all, and the annual rainfall is approximately 1200 mm.

All animals are grazed outside throughout the year. It is the environment coupled with the large number of breeding ewes and ewe hoggets carried by the station that makes it possible to set up large scale programmes designed to breed top performing sheep that can handle rugged conditions. . The Mt Linton high fleece weight flock is a natural extention of Alastair McGregor’s desire to explore the limit of the Romney’s production potential. The idea of a high fleece weight flock was first mooted in discussion with the late Dr Hugh Hawker of the M.A.F. Invermay Agricultural Centre.

At the time, Dr Hawker said the aim was to quickly develop a gene pool of high fleece weight sheep that the industry could exploit.

In 1983 the M.A.F. set up a research flock at it’s Woodland’s Research Station, near Invercargill where the M.A.F. team, led by Dr Hawker, screened 32,000 Romney hoggets. Half of these animals were from Mt Linton Station. Eventually, Mt Linton stock made up half the research flock of 200, which represents the top 0.6 per cent on greasy fleeceweight of the 32,000 screened.

To obtain high fleece weight rams, 25,000 Sheeplan registered animals were screened over two years, and 20 ram hoggets with the most exceptional fleece weights selected. A control flock of 100 randomly selected animals was also set up for comparative purposes.