NZFarmer : February 17th 2009
www.straightfurrow.co.nz News Consistency key to scanning sheep By HOWARD KEENE HEEP breeders hope a trial comparing the results of eye muscle scanners at Lincoln University will help bring con- sistency to a procedure which is important in improving meatiness in breeding flocks. The New Zealand Sheepbreeders Association and Meat & Wool NZ held a workshop recently where all eight practising scanners, two for the North Island and six from the South, each scanned the same mob of 25 rams twice. S This will provide a check that scanners are being con- sistent, and will offer a degree of comparison between scan- ners. It is known that the readings from sheep can vary from one day to another depending on how relaxed they are. As a result of concern from some sheep breeders, the organisers hope to be able to give accreditation to scanners and standardise techniques and procedures. “One of the goals is to improve our accuracy,’’ said Sheepbreeders Association chief executive Greg Burgess. “In future we hope to develop a means so that our information can go directly to SIL (Sheep Improvement Ltd) without doing it manually.’’ “A lot of members have been concerned that some scanners have been getting higher values than others. This is a good opportunity to get everyone on the same page.’’ Scanner Mike Stephens from Dunedin pitted his skills against all the other scanners. A former musterer and farmer he trained to be a scanner after he hurt his back. His training included a 10 week stint in Canada scanning cattle. He now works for Asure Quality and scans sheep and deer for a couple of months a year. He said in the past a lot of breeders had used scanning figures as a marketing tool rather than as a development tool for their studs to improve meatiness. Big gains in meat versus weight were made early on, and up to a few years ago a lot of guys were using it as a sell- ing point rather than for improving stock. Mr Stephens said he expect- ed to see a small amount of difference between results. “The general opinion is if you get the same person scanning year after year you will get the same result.’’ Scanners have to judge on the screen where the edge of muscle lies. Another Dunedin scanner Barry McLellan demonstrated using oil as a lubricant and placing the ultrasound probe on the sheep’s back about half way between the last rib and the hip bone. “I adjust the probe position on the skin to get the deepest part of the muscle.’’ He said in his opinion it was possible to get the accuracy of the depth of the eye muscle to within one millimetre, and the width to within two to three millimetres. Although the results of the workshop have not been analysed yet, Lincoln University senior technical officer Nigel Jay indicated “the repeatability was pretty good’’. “That was one of the things that we were looking for. Some breeders were looking for consistency between scan- ners.’’ He said the most important thing when the figures were put into SIL was that a scan- ner was consistent within a flock. email@example.com Straight Furrow • February 17, 2009 11 Eye muscle scanners can be used as a tool for studs to improve the meatiness of their sheep.
February 25th 2009