AUSTRALIA’S Corriedale Performance Group is also going for gold as the nation’s athletes line up to compete at the Summer Olympics in Rio de Janeiro, Brazil, this week.
The group of performance-orientated Corriedale breeders has settled on an Olympic-themed system to identify their top rams for buyers this year.
Sires ranked in the top 10 percent of the Lambplan Dual Purpose $ Index (DP$) for the breed will now be known as Gold rams. Silver rams in the next 15pc — the 75-90 percentile range – and Bronze rams are those of average performance in the 40-75pc percentile on the Dual Purpose $ Index.
The Corriedale Performance Group is a group of breeders committed to improving the Corriedale breed and last year sold more than 40pc of Australia’s Corriedale rams into Corriedale, Merino and composite flocks.
CPG chairman Peter Blackwood said the new branding system would help people understand sires with higher performing genetics as a group rather than as individuals. All CPG members use LambPlan for performance recording and sheep are selected on Australian Sheep Breeding Values (ASBVs) with the aim of producing a maternal sheep adapted to high rainfall country and producing a higher value fleece.
The group has an active young sire program where semen from the best young rams from Australia and New Zealand are used across flocks to provide genetic links between flocks and accurate breeding values of those rams. Mr Blackwood said the group members are committed to making it easier for clients to identify superior rams and market them appropriately. The Lambplan Dual Purpose $ Index puts an emphasis on reproduction, growth and wool production, in that order. CPG members also place emphasis on structural correctness, muscle and fat scans, and maintaining a Corriedale-style fleece.
Mr Blackwood said it is almost impossible to genetically improve low heritability traits like reproductive rate without using ASBVs. Genetic progress in growth and wool is also much faster with ASBvs, he said. Given that a young ram’s ASBVs are not estimated with 100pc accuracy, the group has decided to group rams into performance categories as those within a category will perform similarly, he said.
Peter and Claire Blackwood have been using ASBVs in their flock since 2006 and their flock’s average DP$ has increased from about 105 to 119.
“In that 10 years I believe our lambing percentages have increased by about 20pc and we are achieving a marketable.”
Using White Suffolk lambs over Corriedale ewes, they are producing a 22-23kg cwt in four months from September-drop lambs.
“I reckon we are turning them off a month earlier.
“Our old Corriedale ewes taken out of the stud marked 152pc and 153pc last year.”
The Corriedale Performance Group looked at simple ranking systems around the world and based its Gold-Silver-Bronze criteria on successful systems in the Irish beef and NZ sheep industry. It decided to base the grades on percentile bands because the group is making significant genetic progress each year. The average DP$ for 2014-15 drop Corriedale rams from performance recorded ewes is now 114, but top ram lambs are indexing around 130. Currently, a Gold ram’s ASBVs are $20 above average on the Dual Purpose $ Index. This means his progeny that inherit half of his genes will be $10 per ewe joined more valuable than those by an average ram. Thus, if he is joined to 100 ewes over a couple of years, then he is worth $1000 more than an average ram, the group said.