Demand for ethically sourced non-mulesed Merino wool is a critical driver of the wool market both domestically and internationally. Hence, there is interest from producers in reducing the use of painful procedures such as mulesing without negatively impacting the amount of wool produced. Genetic solutions have been proposed, with producers moving towards breeding Merino sheep with lower breech wrinkle scores to negate the need for mulesing. However, there is concern that reducing wrinkle scores will also reduce fleece weight. This study compared the trend in Early Breech Wrinkle (EBWR) and Yearling Clean Fleece Weight (YCFW) Australian Sheep Breeding Values (ASBVs) between 2009 and 2017. Data was extracted from the MERINOSELECT database and analysed using descriptive statistics. These results were graphed to visualise the trend in the data. It was found that between 2009 and 2017, YCFW increased from +7.5 to +18.2, while EBWR decreased from -0.2 to – 0.4. In addition, EBWR and YCFW were not significantly correlated (r=0.009). As a result, fleece weight has not been negatively impacted by breeding Merino sheep with lower breech wrinkle scores. Despite representing only a portion of the entire Australian Merino flock, the results provide the Merino industry with vital insight into the current genetic landscape of these breeding traits. Merino producers can integrate this knowledge into their breeding program to reduce costs, increase profits and address animal welfare concerns.
Breech flystrike; Merino sheep; mulesing; breeding; wool production; Australia
ASBV, Australian Sheep Breeding Value; EBWR, Early Breech Wrinkle; YCFW, Yearling Clean Fleece Weight