DPIRD Katanning Yardstick sheep trial field day attracts avid performance breeders

A group of Merino stud breeders were updated on their sire evaluation data at the Department of Primary Industries and Regional Development’s Katanning Sheep Field Day. DPIRD research scientist and trial manager John Paul Collins welcomed more than 30 people to the Yardstick Merino Sire Evaluation Trial held at the DPIRD Katanning Research Station on October 27. The trail which has been ongoing since 1993, compares the breeding performance of a Merino sire by evaluating its progeny and their expressed traits relative to the progeny of other sires in the trial. It uses a consistent ewe base joined to sires via an AI program and the resulting progeny are evaluated to assess a sire’s breeding performance for a large number of traits which are important to breeders and commercial producers. The results assist in the selection of sires suitable for a large range of breeding objectives. Mr Collins said Yardstick was one of 11 active Merino sire evaluation sites located across Australia. “The 2021 drop Yardstick Merino sire evaluation progeny were from 12 leading sires,” he said. “The progeny were in an environment with 480mm of growing season rainfall.” Mr Collins said each sire was allocated 50 ewes that were randomly selected and the resulting progeny of each sire was measured in relation to the progeny of other sires. “The key point of this trial is it’s an independent evaluation of the progeny of individual rams in local environments,” he said. “We collect over 30 measurements between birth and hogget shearing — there is more collection of visual traits than measured traits. “The classer, James Culleton, classed the sheep pre-shearing with no idea of the sire’s breeding pedigree.” Mr Collins said the trial used link sires nominated by the national sire evaluation committee, with this trial including Miramoona 140012 and Yarrawonga 170193. “By participating in sire evaluation it is a good cost-effective approach to joining MerinoSelect because you’re getting this linkage and improving the accuracy of the Australian Sheep Breeding Values,” he said. “The trial uses adjusted sire means which corrects raw data for non-genetic factors that will affect production — the main ones are sex and birth type. “A twin will cut less wool, so we collect for birth type, single or multiple.” “A twin will cut less wool, so the data is corrected for birth type — single, multiple or triplet.” Mr Collins said flock breeding value data was produced and that information was sent to the MerinoSelect data base and used to improve the accuracy of ASBVs. From the 12 sires that were used in the trial, the average adjusted sire means for wool traits were HFD 17.4, 18.7 HFDCV, 104.5 HSL and 43.8 HSS. The average weight carcase traits were 26.7 WWT, 37.3 PWT, 40 YWT, 55 HWT, 21.5 YEMD and 2.1 YFAT. Also calculated from data recorded within-site and within-drop were the flock breeding values. They were expressed as the genetic performance of a sire relative to another sire in the evaluation as mated to the same standard of ewes. Hill Padua stud co-principal Anthony Thomas, of Three Springs, was a first time participant at Yardstick. “We were advised in 2008 to measure the stud using ASBVs and found out they worked,” he said. Stud manager Fred Echaniz said the sire they put in the trial, Hill Padua 191060, had really good growth with above-average eye muscle depth and fat and high density wool. “At Hill Padua, structure is a must, an animal has to have good legs, good neck extension and plain and deep bodied,” he said. “We also want 120 per cent weaned lambs and six kilograms of wool. “Our lambs grow fast and yield 46 per cent dressed weight — that’s our direction, we are chasing wool cut with a goal of 6kg/head/year, but we don’t want to lose any fertility, EMD or fat.” Billandri Poll Merino stud co-principal Bill Sandilands, of Kendenup, has been a participant since the first Yardstick in 1993. “We slecet on MP+ with some emphasis on fat and weaning rate,” he said. “Yardstick gives me a comparison of where my breeding is against other industry leading sires. “This builds confidence in my approach to measuring sheep which I take great personal pride in doing.” Edale stud co-principal James Gardiner, who runs both a fine and ultrafine Merinos at Moora entred an ultrafine sire, Edale 15X370, which was one of the trait leaders for low fibre diamater. “Our breeding objective — with a focus on wool is to produce high cutting sheep below 15 microns,” he said. “The trial sire was producing up to up to 8kg of 16 micron wool. “Our interest in the trial was to see how this ultrafine ram would perform.” Coromandel Poll Merino stud Michael Campbell, of Gairdner, said his trial sire, Coromandel Poll 180193, was meeting the stud;s breeding objectives of lower microns and good wool cuts of about 6 to 7kg. “He is from a line of ET breeding — always good to measure animals and compare our breeding objectives to what our peers are achieving,” he said.