Selection for feed efficiency does not change the selection for growth and carcass traits in Nellore cattle

Abstract. A variety of available terminal sire lines makes the choice of terminal sire line complex for the pig producer. Higher birth weights are important for subsequent growth performance and selection for this trait is also necessary in sire lines. The aim was to investigate the effect of sire line, birth weight and gender on growth performance, carcass traits and meat quality. In total 3844 crossbred pigs from Camborough Pig Improvement Company (PIC) dams matched with either a Synthetic (A) or Piétrain (B) sire line were used. Pigs from line A grew faster (p<0.01), showed higher feed intake (p<0.01) and reached a higher final body weight (p≤0.01), but they had a similar efficiency (p=0.179). Leaner carcasses and heavier primal cuts (p<0.001) were observed in pigs from line B. Carcasses from pigs sired by line A had higher meat quality (p<0.001). Males had a higher growth rate (p≤0.05) but had a poorer feed efficiency (p<0.01). Heavier birth weight pigs and females had leaner, higher value carcasses with heavier primal cuts (p<0.001) compared to middle and low birth weight females or males. Sire line by sex interactions was significant for growth (p≤0.05) and carcass traits (p<0.001). Interaction between sire line and birth weight classes were only detected for loin depth (p<0.01). Line A is preferable if the numbers of fatting pigs per fattening place and year should be improved, and line B is an option to increase leanness and carcass primal cuts.

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Genetic parameters and response to selection for post-weaning weight gain, visual scores and carcass traits in Hereford and Hereford×Nellore cattle

Livestock Science ◽

10.1016/j.livsci.2010.11.013 ◽

2011 ◽

Vol 137 (1-3) ◽

pp. 231-237 ◽

Cited By ~ 9

Author(s):

Fábio Luiz Buranelo Toral ◽

Vanerlei Mozaquatro Roso ◽

Cláudio Vieira de Araújo ◽

João Cruz Reis Filho

Keyword(s):

Weight Gain ◽

Genetic Parameters ◽

Carcass Traits ◽

Response To Selection ◽

Weaning Weight ◽

Nellore Cattle ◽

Selection For

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Effect of dietary protein content on performance, feed efficiency and carcass traits of feedlot Nellore and Angus × Nellore cross cattle at different growth stages

The Journal of Agricultural Science ◽

10.1017/s0021859617000958 ◽

2018 ◽

Vol 156 (1) ◽

pp. 110-117 ◽

Cited By ~ 4

Author(s):

P. M. Amaral ◽

L. D. S. Mariz ◽

D. Zanetti ◽

L. F. Prados ◽

M. I. Marcondes ◽

...

Keyword(s):

Feed Efficiency ◽

Average Daily Gain ◽

Carcass Traits ◽

Subcutaneous Fat ◽

Experimental Period ◽

Growth Stages ◽

Linear Effect ◽

Randomized Design ◽

Nellore Cattle ◽

Two Stages

AbstractAn experiment was conducted to evaluate whether a reduction in dietary crude protein (CP) and genotype affects animal performance, feed efficiency and carcass traits of beef cattle at different stages of the feedlot. Twenty-two Nellore and 22 crossbred F1 Angus × Nellore (Nellore: 8 months, initial body weight (iBW) = 212.7 kg; Crossbred: 8 months, iBW = 226.1 kg) were used in this experiment. The experiment was conducted in a complete randomized design with six replicates, in a 2 × 3 factorial design. The factors were two genotypes (Nellore and Crossbred) and three CP concentrations (100, 120 and 140 g/kg dry matter [DM]). The experimental period lasted 224 day, being divided into two stages (Backgrounding = 112 day, and Finishing = 112 day). At the end of the experiment, all animals were slaughtered to evaluate their carcass characteristics. Similar patterns were observed during backgrounding and finishing phases on intake and average daily gain (ADG) regarding genotype. Intakes of DM, organic matter, CP, neutral detergent fibre, non-fibre carbohydrates and total digestible nutrients, ADG (kg/day) and feed efficiency were greater in Crossbred animals than Nellore in both phases. During the backgrounding phase, dietary CP did not influence DM intake. However, a linear effect of CP on ADG was observed in the backgrounding phase. During finishing, Nellore cattle fed 100 g CP/kg DM presented lower ADG than Nellore fed 120 and 140 g CP/kg DM. Crossbred animals were heavier than Nellore at the beginning and end of the trial. Crossbred animals also gained more carcass, retained more CP and fat, and had a greater subcutaneous fat thickness during the experiment compared with Nellore. There was a quadratic effect of dietary CP on retained CP and dressing. The current study found that crossbred animals (F1 Angus × Nellore) not only had greater performance, but also better carcass traits compared with Nellore, representing an option for increasing productivity. Also, it is possible to adjust diets according to phase. During the backgrounding stage, 140 g CP/kg DM should be used, being reduced to 120 g CP/kg DM during the finishing stage of feedlot for Nellore and to 100 g CP/kg DM for Crossbred, without affecting performance adversely.

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Genetic analysis of residual feed intake adjusted for fat and carcass and performance traits in a Nellore herd

Ciência Rural ◽

10.1590/0103-8478cr20151505 ◽

2017 ◽

Vol 47 (2) ◽

Cited By ~ 6

Author(s):

Giovanna Faria de Moraes ◽

Luiza Rodrigues Alves Abreu ◽

Isabel Cristina Ferreira ◽

Idalmo Garcia Pereira

Keyword(s):

Feed Intake ◽

Feed Efficiency ◽

Carcass Traits ◽

Residual Feed Intake ◽

Genetic Evaluation ◽

Phenotypic Correlation ◽

Performance Traits ◽

Fat Thickness ◽

Selection For ◽

And Performance

ABSTRACT: The study of the genetic evaluation of residual feed intake adjusted for fat (RFIFat) is important for the appropriate use of feed efficiency in selection programs. The objective was to analyze the influence of selection for RFIF at on carcass and performance traits by estimating various genetic parameters. Data were analyzed from five tests of feed efficiency, which were conducted with 677 Nellore males. Genetic evaluation was performed by Bayesian inference using an animal model via single- and two-trait analyses. Variables analyzed were dry matter intake, average daily gain, RFIFat, rib eye area, back fat thickness, rump fat thickness, marbling score, and subcutaneous fat thickness. The posterior mean distributions estimated at each analysis were used to estimate heritability of the traits and to perform various correlations. The studied traits showed high heritability estimates, and they should respond well to selection. The RFIFat presented a phenotypic correlation with carcass traits (which was next to zero), and there was also a negative genetic correlation. Additive genetic variability for RFIFat showed that selection for this trait can promote genetic gains in future generations, resulting in animals that are efficient in terms of nutrient use, and according to the genetic and phenotypic correlations, with no significant negative changes to carcass traits.

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