Genetic and phenotypic parameter estimates for feed intake and other traits in growing beef cattle, and opportunities for selection123
- 1 November 2011
- journal article
- Published by Oxford University Press (OUP) in Journal of Animal Science
- Vol. 89 (11), 3452-3459
- https://doi.org/10.2527/jas.2011-3961
Abstract
Growth, feed intake, and temperament indicator data, collected over 5 yr on a total of 1,141 to 1,183 mixed-breed steers, were used to estimate genetic and phenotypic parameters. All steers had a portion of Hereford, Angus, or both as well as varying percentages of Simmental, Charolais, Limousin, Gelbvieh, Red Angus, and MARC III composite. Because the steers were slaughtered on various dates each year and the animals thus varied in days on feed, BW and feed data were adjusted to a 140-d feeding period basis. Adjustment of measures of feed efficiency [G:F or residual feed intake (RFI), intake adjusted for metabolic body size, and BW gain] for body fatness recorded at slaughter had little effect on the results of analyses. Average daily gain was less heritable (0.26) than was midtest BW (MBW; 0.35). Measures of feed intake had greater estimates of heritability, with 140-d DMI at 0.40 and RFI at 0.52; the heritability estimate for G:F was 0.27. Flight speed (FS), as an indicator of temperament, had an estimated heritability of 0.34 and a repeatability of 0.63. As expected, a strong genetic (0.86) correlation was estimated between ADG and MBW; genetic correlations were less strong between DMI and ADG or MBW (0.56 and 0.71). Residual feed intake and DMI had a genetic correlation of 0.66. Indexes for phenotypic RFI and genotypically restricted RFI (no correlation with BW gain) were compared with simple economic indexes incorporating feed intake and growth to elucidate expected selection responses under different criteria. In general, few breed differences were detected across the various measurements. Heterosis contributed to greater DMI, RFI, and MBW, but it did not significantly affect ADG, G:F, or FS. Balancing output (growth) with input costs (feed) is needed in practicing selection, and FS would not be recommended as an indicator trait for selection to change feed efficiency. An index including BW gain and RFI produced the best economic outcome. Copyright © 2011. American Society of Animal Science.Keywords
This publication has 15 references indexed in Scilit:
- Phenotypic and genetic parameters for different measures of feed efficiency in different breeds of Irish performance-tested beef bullsJournal of Animal Science, 2010
- Effect of breed composition on phenotypic residual feed intake and growth in Angus, Brahman, and Angus × Brahman crossbred cattleJournal of Animal Science, 2009
- Selection response and genetic parameters for residual feed intake in Yorkshire swine1Journal of Animal Science, 2008
- Genetic parameters for residual feed intake in growing pigs, with emphasis on genetic relationships with carcass and meat quality traitsJournal of Animal Science, 2007
- Comparison of feed energy costs of maintenance, lean deposition, and fat deposition in three lines of mice selected for heat loss1Journal of Animal Science, 2006
- An evaluation of production and economic efficiency of two beef systems from calving to slaughter1Journal of Animal Science, 2005
- Variances and covariances between productive and adaptive traits and temperament in a composite breed of tropical beef cattleLivestock Production Science, 2001
- Genetic and phenotypic variance and covariance components for feed intake, feed efficiency, and other postweaning traits in Angus cattle.Journal of Animal Science, 2001
- Genetic and statistical properties of residual feed intakeJournal of Animal Science, 1993
- Cow Type and the Nutritional Environment: Nutritional AspectsJournal of Animal Science, 1985