title: Sire carcass breeding values affect body composition in lambs--2. Effects on fat and bone weight and their distribution within the carcass as measured by computed tomography.
abstract: This study assessed the effect of paternal Australian Sheep Breeding Values for post weaning c-site eye muscle depth (PEMD) and fat depth (PFAT), and post weaning weight (PWWT) on the composition of lamb carcasses. Composition was measured using computed tomography scans of 1665 lambs which were progeny of 85 Maternal, 115 Merino and 155 Terminal sires. Reducing sire PFAT decreased carcass fat weight by 4.8% and increased carcass bone by 1.3% per unit of PFAT (range 5.1 mm). Increasing sire PEMD reduced carcass fat weight by 3.8% in Maternal and 2% in Terminal sired lambs per unit of PEMD (range 4.3 and 7.8 mm), with no impact on bone. Increasing sire PWWT reduced carcass fat weight, but only at some experimental locations. Differences in composition varied between sire types with Maternal sired lambs having the most fat and Merino sired lambs the greatest bone weight. Genetic effects on fatness were greater than the environmental or production factor effects, with the converse true of bone.
authors.affiliation: Australian Cooperative Research Centre for Sheep Industry Innovation, University of New England, Armidale, NSW 2351, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia. Electronic address: F.Anderson@murdoch.edu.au.
authors.forename: F
authors.initials: F
authors.lastname: Anderson
authors.affiliation: Australian Cooperative Research Centre for Sheep Industry Innovation, University of New England, Armidale, NSW 2351, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Williams
authors.affiliation: Australian Cooperative Research Centre for Sheep Industry Innovation, University of New England, Armidale, NSW 2351, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Pannier
authors.affiliation: Australian Cooperative Research Centre for Sheep Industry Innovation, University of New England, Armidale, NSW 2351, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
authors.forename: D W
authors.initials: DW
authors.lastname: Pethick
authors.affiliation: Australian Cooperative Research Centre for Sheep Industry Innovation, University of New England, Armidale, NSW 2351, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
authors.forename: G E
authors.initials: GE
authors.lastname: Gardner
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology*; D000818:Animals; D001823:Body Composition / Q000235:genetics* / Q000502:physiology; D001842:Bone and Bones / Q000033:anatomy & histology*; D001947:Breeding; D008297:Male; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D012756:Sheep / Q000033:anatomy & histology* / Q000235:genetics / Q000502:physiology; D014057:Tomography, X-Ray Computed / Q000662:veterinary*
keywords: Bone; Breeding value; Computed tomography; Fat; Lamb