title: Relationship between phenotype, carcass characteristics and the incidence of dark cutting in heifers.
abstract: Previous research has suggested that cattle predisposed to dark cutting can be identified from live animal or carcass characteristics. This hypothesis was tested using production and phenotype data from an existing data set collected from heifers (n=467) on study at three farms. Carcasses in the data set graded Canada AAA (n=136), AA (n=296), A (n=14), and B4 (dark cutting, n=21). Farm was identified as significant (P=0.0268) by CATMOD analysis and slaughter weight and carcass weight accounted for the variation in dark cutting frequency across the farms. Analysis of variance indicated that dark cutting heifers had reduced weight at weaning (P<0.0001) and at slaughter (P<0.0001), and produced reduced weight carcasses (P<0.0001). Results of logistic regression indicated that the probability of dark cutting was decreased in heifers slaughtered at live weight greater than 550kg and in carcasses weighing greater than 325kg.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, 410 Agriculture/Forestry Building, University of Alberta, Edmonton T6G 2P5, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Mahmood
authors.affiliation: Alberta Agriculture and Rural Development, 6000 C & E Trail, Lacombe T4L 1W1, Canada.
authors.forename: J A
authors.initials: JA
authors.lastname: Basarab
authors.affiliation: Department of Agricultural, Food and Nutritional Science, 410 Agriculture/Forestry Building, University of Alberta, Edmonton T6G 2P5, Canada.
authors.forename: W T
authors.initials: WT
authors.lastname: Dixon
authors.affiliation: Department of Agricultural, Food and Nutritional Science, 410 Agriculture/Forestry Building, University of Alberta, Edmonton T6G 2P5, Canada. Electronic address: hbruce@ualberta.ca.
authors.forename: H L
authors.initials: HL
authors.lastname: Bruce
mesh_terms: D000003:Abattoirs; D000818:Animals; D002170:Canada; D002417:Cattle; D003116:Color / Q000592:standards*; D005260:Female; D016015:Logistic Models; D008297:Male; D010641:Phenotype; D000069466:Red Meat / Q000592:standards*; D014481:United States; D016885:United States Department of Agriculture
keywords: Average daily gain; Carcass weight; Dark cutting beef; Marbling score; Slaughter weight