AUSTRALIAN Sheep Breeding Values (ASBV) for dag and breech cover have been launched by Sheep Genetics.
Together with the early breech wrinkle ASBV released in September 2009, sheep producers now have three genetic selection tools to assist in breeding animals with lower risk of breech and tail flystrike.
The launch further demonstrates the wool industry’s commitment to flystrike prevention, Australian Wool Innovation’s top R&D priority. Over $25 million has been invested on this area of research and development since 2005.
The launch of these Breeding Values is the result of significant R&D investment into AWI’s ‘Breeding for Breech Flystrike Resistance’ trial sites, Australian Merino Sire Evaluation Association, the eight Sheep CRC Information Nucleus sites and also the supply of data by Industry Flocks. The analysis methodology has been created by the Sheep Genetics Technical Committee with major inputs from the Animal Genetics Breeding Unit (AGBU).
Dags and wrinkle are the two indicator traits most strongly correlated with the risk of breech flystrike. Sheep with negative ASBVs for dag, wrinkle and breech cover will breed progeny with lower breech wrinkle, lower dag and lower breech cover and thus lower risk of breech and tail flystrike.
The importance of these ASBVs relative to each other depends on the sheep and their environment. In high dag zones, dags are likely to be the most important; in low dag zones, wrinkle is likely to be the most important according to Sheep Genetics manager, Sam Gill.
“However, research has also shown the relationship between breech wrinkle, and fleece weight must be carefully managed to prevent negative production effects. This can be achieved through watching fleece weight ASBVs. There are enough low wrinkle, high fleece weight animals available for selection and it is important to have ASBVs for both to balance these traits,” he added.
Adoption of the early breech wrinkle ASBVs has been rapid by MERINOSELECT members. Prior to launch in September 2009, eight out of 150 members collected breech wrinkle data, one year later 66% of the 2009 drop animals have been assessed for early breech wrinkle.
“We believe that the uptake of dag and cover measurements will be similar to wrinkle,” Mr Gill said.
The research was funded by Australian Wool Innovation and Meat and Livestock Australia, together with Australian Merino Sire Evaluation Association and the Sheep CRC.
Sheep Genetics manager Sam Gill, CSIRO researcher Dr Jen Smith and DAFWA scientist Dr Brown Bieser spoke at the launch of the new ASBVs via webinar.