Estimation of genetic parameters and selection of elephant-grass ( Pennisetum purpureum Schumach.) for forage production using mixed models

Abstract. The objective of this paper was to select a suitable data subset and statistical model for the estimation of genetic parameters for 36 traits of the linear type in 977 Old Kladruber horses. Two subsets were tested to identify a suitable subset for analysis. One subset included repeated evaluation of certain individuals, whereas the other did not. The most suitable subset included repeated evaluation (n=1 390). The selection of a suitable model was made from 4 candidate models. These models comprised a number of random effects (direct individual effect and animal permanent environmental effect of the animal) and a number of fixed effects (colour variant, stud, colour variant × stud interaction, sex, age at description, year of birth, year of description). The model was selected based on the Akaike information criterion (AIC, Akaike 1974), residual variance and heritability coefficient. The model that included colour variant, stud, colour variant × stud interaction, sex, age at description, and year of description as fixed effects and direct individual and animal permanent environment as random effects was the most suitable model for the estimation of genetic parameters and for the subsequent estimation of breeding values.

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Estimation of Genetic Parameters for Body Weight and Some Colour Traits in the Seventh-generation Index Selected Nigeria Heavy Local Chicken Ecotype

Agricultural Science Digest - A Research Journal ◽

10.18805/ag.d-359 ◽

2021 ◽

Author(s):

I.J. Ohagenyi ◽

F.C. Iregbu ◽

V.C. Udeh

Keyword(s):

Body Weight ◽

Genetic Parameters ◽

Genetic Correlations ◽

The Body ◽

Pedigree Selection ◽

Egg Colour ◽

Local Chicken ◽

Range Test ◽

Estimation Of Genetic Parameters ◽

Selection Of

Background: This study was conducted to estimate the genetic parameters of body weight and some colour traits in seventh generation (G7) index selected Nigerian Heavy Local Chicken Ecotype (NHLCE) progenies at point of lay to 12 weeks. Methods: 5 sires and 12 hens were used to generate the progenies used for the experiment. Traits measured included weekly body weight, egg colour, beak colour and feather colour. Data collected were subjected to one way analysis of variance in a Paternal half sib analysis using Animal model of SAS (2003). Four weeks body weight measurements, egg colour, beak colour and feather colour for 5 sires ranged from 1.29±0.05 1.54±0.07; 2.55±0.02 to 4.00±0.02; 2.45±0.02 to 4.83±0.02 and 1.73±0.02 to 4.58±0.04 respectively. Result: The new Duncan’s multiple range test shows that sire families are similar (p greater than 0.05) in the body weight and beak colour, but significantly differed (p greater than 0.05) in the egg colour and feather colour. The heritability estimates of mature body weight for week 3 was medium, while estimates of heritability for weekly mature body weight for weeks 1, 2 and 4, egg colour, beak colour and feather colour of NHLCE were low heritability. Low h2 of traits suggest that progeny and pedigree selection could be employed for improvement of the egg colour, beak colour and feather colour of NHLCE. The study showed positive genetic correlations between beak colour and egg colour, negative genetic correlations between beak and feather colour. This means that no decision can be taken in isolation as the selection of one trait will have consequences on other traits.

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Use of robust multivariate linear mixed models for estimation of genetic parameters for carcass traits in beef cattle

Journal of Animal Breeding and Genetics ◽

10.1111/jbg.12093 ◽

2014 ◽

Vol 131 (6) ◽

pp. 504-512 ◽

Cited By ~ 3

Author(s):

S.O. Peters ◽

K. Kizilkaya ◽

D.J. Garrick ◽

R.L. Fernando ◽

E.J. Pollak ◽

...

Keyword(s):

Beef Cattle ◽

Mixed Models ◽

Genetic Parameters ◽

Linear Mixed Models ◽

Carcass Traits ◽

Estimation Of Genetic Parameters

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Estimation of Genetic Parameters and Selection of Parents for Hybridization in Dolichos Bean [Dolichos lablab L.]

International Journal of Current Microbiology and Applied Sciences ◽

10.20546/ijcmas.2017.612.046 ◽

2017 ◽

Vol 6 (12) ◽

pp. 381-395

Author(s):

Niharika Jyotirekha Nayak ◽

Praveen Kumar Maurya ◽

Anirban Maji ◽

Soumitra Chatterjee ◽

Amit Ranjan Mandal ◽

...

Keyword(s):

Genetic Parameters ◽

Dolichos Lablab ◽

Estimation Of Genetic Parameters ◽

Selection Of

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Selection of a suitable data set and model for the estimation of genetic parameters of the weaning weight in beef cattle

Archives Animal Breeding ◽

10.5194/aab-50-562-2007 ◽

2007 ◽

Vol 50 (6) ◽

pp. 562-574

Author(s):

L. Vostrý ◽

J. Přibyl ◽

Z. Veselá ◽

V. Jakubec

Keyword(s):

Beef Cattle ◽

Fixed Effects ◽

Genetic Parameters ◽

Genetic Correlations ◽

Genetic Effect ◽

Suitable Model ◽

Data Set ◽

Weaning Weight ◽

Estimation Of Genetic Parameters ◽

Selection Of

Abstract. The objective of this paper was to select a suitable data subset and statistical model for the estimation of genetic parameters for weaning weight of beef cattle in the Czech Republic. Nine subsets were tested for the selection of a suitable subset. The subsets differed from each other in the limit of sampling criteria. The most suitable subset satisfied these conditions: at least 5 individuals per each sire, 5 individuals per HYS (herd, year, season), 2 sires per HYS, and individuals per dams that have at least one half-sister and two offspring (n = 4 806). The selection of a suitable model was carried out from 10 models. These models comprised some of the random effects: direct genetic effect, maternal genetic effect, permanent maternal environment effect, HYS, sire × herd or sire × year interaction, and some of the fixed effects: dam’s age, sex (young bull, heifer × single, twin born), HYS, year, herd. The direct heritability (h2a) ranged from 0.06 to 0.17, of maternal heritability (h2m) from 0.03 to 0.06. The genetic correlations between the direct and maternal effect (ram) were in the range of –0.15 –0.42.

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Genetic progress in maize from advanced cycles of reciprocal recurrent selection through REML/BLUP

Australian Journal of Crop Science ◽

10.21475/ajcs.20.14.08.p2562 ◽

2020 ◽

pp. 1295-1301

Author(s):

José Arantes Ferreira Júnior ◽

Gabriel Moreno Bernardo Gonçalves ◽

Jocarla Ambrosim Crevelari ◽

Julio Cesar Fiorio Vettorazzi ◽

Vivane Mirian Lanhellas Gonçalves ◽

...

Keyword(s):

Grain Yield ◽

Mixed Models ◽

Variance Components ◽

Genetic Parameters ◽

Recurrent Selection ◽

Yield Potential ◽

Reciprocal Recurrent Selection ◽

Genetic Progress ◽

Advanced Cycles ◽

Selection Of

Breeding methods such as reciprocal recurrent selection (RRS) is very important alternative to breeders. This strategy, besides allowing continuous genetic progress, helps maintaining the genetic variability of populations. The aim of the present study was to estimate genetic parameters, as well as to predict selection gains in advanced cycles of reciprocal recurrent selection of maize progenies through mixed models. Two selection cycles were considered. We evaluated 196 and 169 progenies in the 15 and 16 cycles, respectively. The yield potential of the progenies was evaluated from the following characteristics: grain yield, number of ears, weight of ears and weight of 100 seeds. The estimate of variance components and the prediction of genetic values were based on the REML/BLUP method. Overall, the genetic parameters were increased in the 16th cycle estimates compared to the previous cycle. It is worth highlighting that heritability coefficient for the grain yield was (0.81) in the 16th cycle, since it resulted in 21% of selection gain. Results showed that, even after sixteen recurrent selection cycles, the populations under selection have high potential for satisfactory genetic gains.

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Assessing the genotypic performance of carioca beans through mixed models

Ciência Rural ◽

10.1590/0103-8478cr20170761 ◽

2018 ◽

Vol 48 (7) ◽

Author(s):

Yure Pequeno de Souza ◽

Paulo Ricardo dos Santos ◽

Maxwel Rodrigues Nascimento ◽

Kleyton Danilo da Silva Costa ◽

Thalyson Vasconcelos Lima ◽

...

Keyword(s):

Mixed Models ◽

Selection Criteria ◽

Genetic Parameters ◽

Block Design ◽

Breeding Programs ◽

Randomized Block Design ◽

Bean Yield ◽

The Mean ◽

Moderate Magnitude ◽

Selection Of

ABSTRACT: Using genotypes adapted to different regions is one of the main ways to increase Brazilian bean yield. The aim of the present study was to assess the genotypic performance of Carioca beans through mixed models. Fourteen Carioca bean genotypes were assessed in four locations in Pernambuco State (Arcoverde, Caruaru, Belém de São Francisco and São João counties) in 2015. The experiments followed a completely randomized block design, with three repetitions. Genetic parameters were estimated according to the REML/BLUP methodology, whereas genotype selection was based on the harmonic mean of relative performance of genetic values method (MHPRVG). The mean genotype heritability had moderate magnitude, high selective accuracy, besides allowing selection of agronomically superior individuals. Genotypes ‘BRS Notável’, CNFC 15480 and ‘IPR 139’ showed good adaptability and grain yield stability. There was agreement among the statistics μ ̂ + g ̂…, stability (MHVG), adaptability (PRVG), and stability and adaptability of genetic values (MHPRVG) in the discrimination of the most productive genotypes, which presented high adaptability and stability. This outcome indicated that these genotypes can be part of the selection criteria regularly used in bean breeding programs.

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SIMULTANEOUS ESTIMATION OF GENETIC PARAMETERS OF LIFETIME REPRODUCTIVE TRAITS IN MICE

Canadian Journal of Animal Science ◽

10.4141/cjas88-145 ◽

1988 ◽

Vol 68 (4) ◽

pp. 1291-1295 ◽

Cited By ~ 2

Author(s):

J. NAGAI ◽

C. Y. LIN ◽

A. J. McALLISTER

Keyword(s):

Genetic Parameters ◽

Mixed Model ◽

Reproductive Traits ◽

Bivariate Analysis ◽

Simultaneous Estimation ◽

Mixed Model Analysis ◽

Reproductive Life ◽

Genetic And Phenotypic Correlations ◽

Estimation Of Genetic Parameters ◽

Selection Of

Heritabilities and correlations between the length of reproductive life and number of parturitions during lifetime in mice were estimated from bivariate full-sib mixed-model analysis. Heritability estimates from sire components were low (0.01) for the two traits and those from dam components were slightly higher (0.06 and 0.05). Estimates of genetic and phenotypic correlations ranged from 0.89 to 0.99. It was concluded that the two traits are virtually the same trait biologically. Implication of these results for selection of lifetime production in mice and dairy cattle is discussed. Key words: Genetic parameters, reproductive trait, bivariate analysis

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