Genetic associations between hip height, body conformation scores, and pregnancy probability at 14 months in Nelore cattle

The aim of this study was to evaluate the genetic variability, genetic and phenotypic associations, and genetic gains of birth (BW), weaning (WW), and yearling (YW) weights, loin muscle area (LMA), backfat thickness (BF), rump fat thickness (RF), scores of body structure (BS), finishing precocity (FS), and muscling (MS) in Nelore cattle. Genetic parameters were obtained through Bayesian inference using BLUPF90 programs. All studied traits showed genetic variability, with heritability ranging from 0.29 to 0.47. In all studied ages, weights presented positive genetic correlations with LMA (ranging from 0.13 to 0.53), being generally stronger in comparison with the other carcass traits analyzed (BF and RF). Similarly, weights were higher genetic associated with BS (0.47–0.92) than with FS (0.18–0.62) and MS (0.22–0.65), respectively. The BF and RF showed positive and moderate genetic associations with FS and MS (0.31–0.36). Genetic trends were significant (P < 0.05) and favorable for WW, YW, and visual scores. Selection for increasing BW, WW, YW, and LMA will result in modest or no change in BF and RF (correlated response ranging from −0.04 to 0.07 mm per generation). In this population, carcass traits must be included in the selection indexes to obtain genetic gains in carcass quality, if desired.

Download Full-text

Genetic associations between age at first calving and heifer body weight and scrotal circumference in Nelore cattle

Journal of Animal Breeding and Genetics ◽

10.1111/j.1439-0388.2008.00791.x ◽

2009 ◽

Vol 126 (5) ◽

pp. 387-393 ◽

Cited By ~ 23

Author(s):

D.A. Grossi ◽

G.C. Venturini ◽

C.C.P. Paz ◽

L.A.F. Bezerra ◽

R.B. Lôbo ◽

...

Keyword(s):

Body Weight ◽

Genetic Associations ◽

Age At First Calving ◽

Scrotal Circumference ◽

Nelore Cattle

Download Full-text

Genetic associations between accumulated productivity, and reproductive and growth traits in Nelore cattle

Livestock Science ◽

10.1016/j.livsci.2007.12.007 ◽

2008 ◽

Vol 117 (2-3) ◽

pp. 139-146 ◽

Cited By ~ 22

Author(s):

D.A. Grossi ◽

O.G. Frizzas ◽

C.C.P. Paz ◽

L.A.F. Bezerra ◽

R.B. Lôbo ◽

...

Keyword(s):

Growth Traits ◽

Genetic Associations ◽

Nelore Cattle

Download Full-text

Genetic study of visual scores and hip height at different ages in Nelore cattle

Animal Production Science ◽

10.1071/an15657 ◽

2017 ◽

Vol 57 (4) ◽

pp. 614 ◽

Cited By ~ 2

Author(s):

D. D. Silveira ◽

L. De Vargas ◽

V. M. Roso ◽

G. S. Campos ◽

F. R. P. Souza ◽

...

Keyword(s):

Variance Components ◽

Selection Criteria ◽

Selection Process ◽

Selection Index ◽

Genetic Correlations ◽

Genetic Associations ◽

Correlated Responses ◽

Genetic Changes ◽

Heritability Estimates ◽

Nelore Cattle

The objective of the present study was to evaluate the genetic variability of visual scores used as selection criteria in Nelore cattle, as well as their associations with yearling hip height (YH) and mature hip height (MH), to determine whether the selection considered would change the hip height of animals. (Co)variance components were obtained by two-trait animal model using Gibbs sampling, including YH or MH in each analysis. Breeding values for YH and MH were used to obtain the response to selection. The posterior mean of the heritability estimates for conformation, finishing precocity (or body condition) and muscling at weaning (WC: 0.21 ± 0.02; WP: 0.21 ± 0.02; and WM: 0.18 ± 0.02 respectively) were lower than those obtained for the same traits at yearling (YC: 0.34 ± 0.02; YP: 0.37 ± 0.02; and YM: 0.38 ± 0.02 respectively). Heritability estimates for YH and MH were 0.28 ± 0.01 and 0.33 ± 0.03 respectively. The results suggested that these traits should respond to selection process, but in different magnitudes. Positive and high genetic correlations were estimated between WC and YH and YC and YH (0.80 ± 0.03 and 0.76 ± 0.03 respectively), and lower values between these scores and MH (0.48 ± 0.09 and 0.36 ± 0.07 respectively). Weak genetic associations were obtained between finishing precocity score and YH and muscling score and YH (ranging from 0.05 ± 0.05 to 0.18 ± 0.06). Moreover, negative and favourable genetic associations between each of WP, WM, YP and YM, and MH (ranging from –0.21 ± 0.07 to –0.12 ± 0.09) were estimated. Correlated responses are expected to be unfavourable for hip height, measured at yearling and at maturity, when animals better genetically evaluated for conformation in relation to finishing precocity and muscling scores are selected. Genetic changes obtained for YH and MH were null (–0.02 cm/year and 0.03 cm/year respectively). It can be explained, in part, by smaller weights in the selection index for conformation rather than finishing precocity and muscling, as applied in the studied herds. However, in herds of beef cattle not evaluated and selected for finishing precocity and muscling scores or that have cows with larger size than acceptable, the adoption of mature hip height as one of the selection criteria can be one alternative for obtaining females with a desirable size.

Download Full-text