Genetic Relationships between Indicator Traits for Fly Strike Resistance and Production Traits in Merino Sheep
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چکیده
Fly strike in sheep has been estimated to cost the Australian sheep industry approximately $280m dollars annually (Sackett et al. 2006) as a result of sheep losses, cost of treatment and loss of wool and carcase production and value. Historically Australian sheep producers have surgically removed skin from around the tail (mulesing) to help avoid fly strike. Although this has proved highly successful in the past, increasing public concern for animal welfare has forced sheep breeders to search for alternatives. One such alternative is to breed fly strike resistant sheep that do not require mulesing. While the breeding objective is to reduce fly strike, the trait itself if not conducive to measurement and direct selection. Research has revealed a number of indicator traits that are more readily measured and related to fly strike (James 2008; Greeff and Karlson 2009; Smith et al. 2009). These traits include wool cover, skin wrinkle, scouring (dags), wool colour and fleece rot. There is now a large data set of these traits in the Sheep Genetic database from both industry and research flocks. A subset of these traits is included in routine analyses to estimate Australian Sheep Breeding Values (ASBVs).
منابع مشابه
Genetic Parameters in Merino Sheep GENETIC RELATIONSHIPS BETWEEN CARCASS QUALITY AND WOOL PRODUCTION TRAITS IN AUSTRALIAN MERINO RAMS
The heritability of carcass quality traits and the genetic correlations between wool production and these carcass quality traits were estimated on 1216 Merino rams. The results showed that carcass quality traits are moderately heritable but pH appears to be lowly heritable. Yellowness and redness of L. dorsi had very low heritability estimate. Moderate negative genetic relationships were found ...
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