Estimation of genetic parameters of feed intake and daily gain in Durocs using data from electronic swine feeders

Abstract. Weaning performance of 10 808 purebred offsprings (4991 male and 5817 female) of 80 sires in 13 farms were analised using animal model. Heritability, breeding value, (co)variance components for weaning weight (WW), preweaning daily gain (PDG), 205-day weight (CWW) were calculated. Farm, parity, year of birth, season of birth, sex were treated as fixed, and the maternal permanent environment was treated as random effects. In case of WW and PDG, the age of the calves at weaning was fitted as a covariant. Data were analyzed with MTDFREML (Boldman et al. 1993) program. The overall mean value and standard deviation of WW, PDG and CWW were 221±47 kg, 1,111±0.21 kg/day and 226±42 kg, respectively. The age of the calves at weaning was 202 days. The direct heritability (h2d) of WW and PDG were 0.57±0.08, 0.49±0.07 and CWW was 0.44±0.06, respectively. The maternal heritability (h2m) of these traits were 0.32±0.09, 0.33±0.10 and 0.33±0.09, respectively. The direct-maternal correlations (rdm) were strong and negative. The medium heritability estimates for direct effects suggest that progeny tests should be used in this population to increase genetic improvement.

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Effects of seasonality and ambient temperature on genetic parameters for production and reproductive traits in pigs

Animal Production Science ◽

10.1071/an10265 ◽

2011 ◽

Vol 51 (7) ◽

pp. 615 ◽

Cited By ~ 8

Author(s):

Craig R. G. Lewis ◽

Kim L. Bunter

Keyword(s):

Feed Intake ◽

Regression Models ◽

Genetic Parameters ◽

Linear Models ◽

Reproductive Traits ◽

Production Traits ◽

Contemporary Group ◽

Effects Of Temperature ◽

Heritability Estimates ◽

Daily Gain

This study examined the effects of season on genetic parameters for production and reproductive traits and quantified within contemporary group effects of temperature on these traits using linear and plateau-linear regression models. From 2003 onwards, data were available on ~60 000 gilts for the routinely recorded production traits (BF: back fat; LADG: lifetime average daily gain) and ~45 000 litters for the sow reproductive traits (TB: total born; NBA: number born alive; BWT: average piglet birthweight). A subset of gilts were also recorded for test period daily gain (TADG), daily feed intake (ADI) and feed conversion ratio (FCR) and, later, as sows (n ~2000) for average daily lactation feed intake (LADI). Least-squares means for some production and reproductive traits significantly differed between seasons: summer and winter means were 2.28 ± 0.017 vs 2.54 ± 0.011 kg/day for ADI, 2.80 ± 0.022 vs 3.21 ± 0.011 kg/kg for FCR, and 1.61 ± 0.02 vs 1.54 ± 0.02 kg for BWT. However, some statistically significant differences (due to large n) were biologically insignificant. Trait variation also differed between seasons, but heritability estimates did not significantly differ from each other. Heritabilities were (summer vs winter): BF: 0.43 ± 0.03 vs 0.41 ± 0.02; LADG: 0.18 ± 0.02 vs 0.16 ± 0.02; TADG: 0.12 ± 0.10 vs 0.08 ± 0.06; ADI: 0.37 ± 0.15 vs 0.22 ± 0.07; FCR: 0.14 ± 0.11 vs 0.17 ± 0.06; TB: 0.09 ± 0.01 vs 0.10 ± 0.01; NBA: 0.06 ± 0.01 vs 0.07 ± 0.01 and BWT: 0.37 ± 0.03 vs 0.32 ± 0.04. Genetic correlations between the same trait recorded in different seasons were generally very high (>0.70), with the exception of TB, where the genetic correlation between spring and autumn was 0.65 ± 0.09, suggesting a genetic component to the effect of seasonal infertility on litter size. Regression models demonstrated that two selection lines had different responses to increasing temperature, despite concurrent selection in the same environment. Plateau-linear models were generally better than linear models for describing changes to production traits with temperature. Based on maximum temperature at the end of performance testing, the estimated temperature thresholds above which lifetime growth performance was compromised were 25.5 and 32.5°C in the two lines. There were only small linear relationships between reproductive traits and temperature. Overall, the ongoing acclimatisation to the thermal environment and the partial confounding of contemporary group with temperature variables (season explained 62% of variation in average daily temperature) are potentially contributing factors to the lack of major differences in heritability estimates between seasons, and the relatively small regression coefficients for the effects of temperature on performance. Nevertheless, temperature can be demonstrated to affect phenotypic outcomes within contemporary groups using commercial data.

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Estimation of Genetic Parameters for Average Daily Gain and Carcass Traits of Hanwoo

Journal of Animal Science and Technology ◽

10.5187/jast.2012.54.5.317 ◽

2012 ◽

Vol 54 (5) ◽

pp. 317-321

Author(s):

Byoungho Park ◽

Taejeong Choi ◽

Jae Gwan Choi ◽

Yun Ho Choy ◽

Kwang Hyun Cho ◽

...

Keyword(s):

Genetic Parameters ◽

Average Daily Gain ◽

Carcass Traits ◽

Daily Gain ◽

Estimation Of Genetic Parameters

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Genetische Beziehungen für das Merkmal Lebenstagszunahme in einem Dreirassenkreuzungsprogramm beim Schwein

Archives Animal Breeding ◽

10.5194/aab-45-481-2002 ◽

2002 ◽

Vol 45 (5) ◽

pp. 481-490

Author(s):

R. Fischer ◽

U. Müller ◽

U. Bergfeld

Keyword(s):

Parameter Estimation ◽

Genetic Association ◽

Genetic Parameters ◽

Average Daily Gain ◽

Genetic Correlations ◽

Point Of View ◽

Large White ◽

Variable Model ◽

Daily Gain ◽

Estimation Of Genetic Parameters

Abstract. Title of the paper: Genetic association for daily gain (lifetime) in an crossbreeding program The aim of this investigation is an analysis of the crossing structure of a three-race crossing program and the genetic relations with respect to the trait average daily gain. For this purpose we examine the genetic relations for their usefulness for a estimation of genetic parameters and breeding values. Finally a parameter estimation is carried out. The data basis consists of 1757 German Large White performances, 34980 Landrace performances and 2775 Pietrain performances in pure breed as well as 92757 performances of the crossings of the mother lines and altogether 13854 Pietrain crossings (1997 PI x DL and 11857 PI x DEDL). The heritabilities for the variable daily gain are in the range from 0.17 to 0.31. The genetic correlations between the mother races and their crossbreedings are around 0.9. Between the pure Pietrain and the Pietrain crossings these values reach only 0.7. Within the two groups of crossings with Pietrains the genetic correlations are almost one. From the genetic point of view it is possible to put together the mother races and their crossings as well as the Pietrain crossings. Thus, for this trait it is sufficient to consider a three variable model with separate investigation of the mother races, the Pietrains and the Pietrain crossings.

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Estimation of Genetic Parameters for Residual feed intake in Duroc pigs

Journal of Agriculture & Life Science ◽

10.14397/jals.2016.50.1.147 ◽

2016 ◽

Vol 50 (1) ◽

pp. 147-153

Author(s):

Na-Rae Song ◽

◽

Yong-Min Kim ◽

Doo-Wan Kim ◽

Soo-Jin Sa ◽

...

Keyword(s):

Feed Intake ◽

Genetic Parameters ◽

Residual Feed Intake ◽

Estimation Of Genetic Parameters

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Estimation of genetic parameters for lambing ease, birthweight and gestation length in Australian sheep

Animal Production Science ◽

10.1071/an14129 ◽

2016 ◽

Vol 56 (5) ◽

pp. 934 ◽

Cited By ~ 8

Author(s):

L. Li ◽

D. J. Brown

Keyword(s):

Animal Models ◽

Environmental Effects ◽

Genetic Parameters ◽

Genetic Correlations ◽

Gestation Length ◽

Phenotypic Variance ◽

Full Dataset ◽

Australian Sheep ◽

Using Data ◽

Estimation Of Genetic Parameters

This study presents estimates of genetic parameters for lambing ease (LE), birthweight (BW) and gestation length (GL) in Australian terminal sire sheep breeds using data from the Sheep Genetics LAMBPLAN database. LE was scored on lambs on a 1–5 scale, with 1 being no assistance and 5 being other such as special veterinary assistance. The full dataset consisted of 43 448 records on LE and its two subsets (the single and twin subsets) based on the birth type of the litter were analysed. Four models with different combinations of random effects consisting of direct genetic, maternal genetic and maternal permanent environmental effects were compared. All traits were analysed using linear animal models and linear sire models with LE further analysed by threshold sire models for all datasets to evaluate the influence of datasets and models on the estimation of genetic parameters. The results showed that multiple-born lambs had shorter GL, less BW and less lambing difficulty than single-born lambs. Lambing difficulty decreased with the increase of dam age from 1.5 to 4.5 years, and then increased afterwards. Genetic parameters using linear animal models were similar to those using linear sire models for all traits. Phenotypic variance and direct heritability were higher for single-born lambs compared with twin-born lambs. No significant maternal permanent environmental effect was detected for LE. Based on results using linear animal models with the full dataset, the direct heritabilities were 0.06 ± 0.01, 0.15 ± 0.01 and 0.52 ± 0.02, the maternal heritabilities were 0.03 ± 0.01, 0.15 ± 0.01 and 0.13 ± 0.02 for LE, BW and GL, respectively. The proportions of maternal permanent environmental effects to the total variances were 0.13 ± 0.01 for BW. Low to moderate direct genetic correlations of 0.31 ± 0.09 (LE and BW), 0.24 ± 0.11 (LE and GL) and 0.08 ± 0.08 (BW and GL) were estimated using tri-variate analysis from the full dataset, indicating the trend that lambs with greater BW and longer GL would result in more lambing difficulty.

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