Genetic parameters for egg production traits in crosses between local and exotic chickens estimated by Bayesian inference

Estimates of genetic parameters for economic traits are important to enable the breeder estimate the breeding value of individuals available for selection. Thus, this study was carried out to estimate genetic parameters namely heritability and genetic correlations among egg production traits in two strain crosses using bivariate animal model in Bayesian (MCMC) method. The egg production data were obtained from four generations which comprised the base population of two commercial egg strains and the local chicken, the inbred population derived from the base population, the F1 crossbred population obtained from the crossing of the local and exotic inbred chickens and the backcross population obtained from the backcrossing of the crossbred to their parents. A total number of 1,138 daughters of 62 sires and 620 dams were used for the study. The autocorrelations among samples in the MCMC chain were less than 0.1 for all lag values indicating that all samples of the posterior distribution were independent. The estimated heritability for age at first egg, body weight at first egg, hen day egg number, weight of first egg, egg weight at thirty week and egg weight at forty week were 0.62, 0.48, 0.47, 0.53, 0.54 and 0.56 for strain 1 crosses and 0.43, 0.48, 0.49, 0.52, 0.52 and 0.53 for strain 2 crosses. The corresponding highest posterior density interval ranged from 0.22 to 0.91 for strain 1 crosses and 0.07 to 0.83 for strain 2 crosses. The genetic correlations among egg production traits ranged from 0.06 to 1.97 in strain 1 and 0.06 to 2.59 in strain 2 crosses. The estimates were within the range reported in literature for egg production traits in chicken and imply that appreciable amount of additive genes exist in the strain crosses which could be used for the selection of superior birds. The magnitude of genetic correlations implies that selection of one trait could lead to correlated response to the other traits.

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Genetic analysis of docility score of Australian Angus and Limousin cattle

Animal Production Science ◽

10.1071/an16240 ◽

2018 ◽

Vol 58 (2) ◽

pp. 213 ◽

Cited By ~ 1

Author(s):

S. F. Walkom ◽

M. G. Jeyaruban ◽

B. Tier ◽

D. J. Johnston

Keyword(s):

Adverse Effect ◽

Animal Model ◽

Genetic Analysis ◽

Genetic Parameters ◽

Genetic Correlations ◽

Production Costs ◽

Breeding Value ◽

Maternal Behaviour ◽

Production Traits ◽

Subjective Score

The temperament of cattle is believed to affect the profitability of the herd through impacting production costs, meat quality, reproduction, maternal behaviour and the welfare of the animals and their handlers. As part of the national beef cattle genetic evaluation in Australia by BREEDPLAN, 50 935 Angus and 50 930 Limousin calves were scored by seedstock producers for temperament using docility score. Docility score is a subjective score of the animal’s response to being restrained and isolated within a crush, at weaning, and is scored on a scale from 1 to 5 with 1 representing the quiet and 5 the extremely nervous or anxious calves. Genetic parameters for docility score were estimated using a threshold animal model with four thresholds (five categories) from a Bayesian analysis carried out using Gibbs sampling in THRGIBBS1F90 with post-Gibbs analysis in POSTGIBBSF90. The heritability of docility score on the observed scale was 0.21 and 0.39 in Angus and Limousin, respectively. Since the release of the docility breeding value to the Australian Limousin population there has been a favourable trend within the national herd towards more docile cattle. Weak but favourable genetic correlations between docility score and the production traits indicates that docility score is largely independent of these traits and that selection to improve temperament can occur without having an adverse effect on growth, fat, muscle and reproduction.

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Genetic parameters for egg weight v. age curve, and other egg production and egg weight traits, in synthetic lines of chickens

Australian Journal of Agricultural Research ◽

10.1071/ar9830085 ◽

1983 ◽

Vol 34 (1) ◽

pp. 85 ◽

Cited By ~ 5

Author(s):

BH Yoo ◽

BL Sheldon ◽

RN Podger

Keyword(s):

Standard Deviation ◽

Genetic Correlation ◽

Egg Production ◽

Genetic Parameters ◽

Genetic Correlations ◽

Egg Mass ◽

Control Line ◽

Egg Weight ◽

Egg Number ◽

Selection For

An exponential curve, W = P-Qexp(- Rt), where W is egg weight at age t, was fitted to egg weights of individual pullets, and genetic parameters were estimated for P, Q and R, the residual standard deviation and other egg weight and egg production characters. The data consisted of records collected over six generations on more than 4000 pullets in two selection lines and a control line which originated from a synthetic gene pool of White Leghorn x Australorp crosses. The half-sib and offspring-on-parent regression estimates of heritability pooled over the lines were 0.23 and 0.33 for P, 0.14 and 0.20 for Q, and 0.14 and 0.25 for R. Genetic correlations were estimated to be -0.10 between P and Q, -0.46 between P and R, and 0.90 between Q and R. These estimates suggest that the egg weight v. age curve may be modified to increase the proportion of eggs in desirable weight grades and reduce the incidence of oversized eggs later in the production year. The genetic correlation between mean weight of first 10 eggs and egg weight at 62 weeks of age was estimated to be 0.68, further suggesting that early egg weight may be improved partly independently of late egg weight. The heritability estimates of egg mass output were not higher than those of egg number in spite of the highly heritable average egg weight being an important component of egg mass, probably because of the negative genetic correlation (r = -0.49) between egg number and average egg weight. The standard deviation of individual pullet's egg weights was moderately heritable and genetically correlated positively with egg weight characters and negatively with egg production; these estimates were consistent with the responses to selection for reduced egg weight variability observed elsewhere

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GENETIC AND PHENOTYPIC ASSOCIATIONS OF JUVENILE BODY WEIGHTS AND EGG PRODUCTION TRAITS IN TWO STRAINS OF RHODE ISLAND CHICKENS

Nigerian Journal of Animal Production ◽

10.51791/njap.v18i.1968 ◽

2021 ◽

Vol 18 ◽

pp. 66-70

Author(s):

O. O. ONI ◽

B. Y. ABUBAKAR ◽

S. O. OGUNDIPE

Keyword(s):

Body Weight ◽

Rhode Island ◽

Sexual Maturity ◽

Egg Production ◽

Genetic Parameters ◽

Laying Hens ◽

Genetic Correlations ◽

Selection Criterion ◽

Production Traits ◽

Body Weights

Data on body weight at 16 (WT16); 20 (WT20) weeks of age and at sexual maturity (WTSM) weight of first egg (WT1st), age at sexual maturity (ASM) and 120-d egg production (EN) were used to estimate genetic parameters in 636 hens of two strains of Rhode Island chikens. There were significant (P.01) differences between the two strains for all traits except for WTSM.The heritability estimates obtained ranged from 0.05 to 0.41 and 0.04 to 0.30 for strains 1 and 2 respectively. The genetic correlations obtained for the various traits were medium to high for the two strains. The phenotypic correlations were generally low but followed the same trend. The results indicate that selected stocks of the two strains would show improvements in egg production and age at sexual maturity if juvenile body weight (WT20) is employed as a selection criterion at housing for laying hens.

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Genetic variation of egg production traits in purebred and crossbred laying hens

Animal Science ◽

10.1017/s135772980005044x ◽

1999 ◽

Vol 68 (3) ◽

pp. 433-439 ◽

Cited By ~ 8

Author(s):

B. Besbes ◽

J. P. Gibson

Keyword(s):

Egg Production ◽

Egg Quality ◽

Genetic Correlations ◽

Egg Laying ◽

Production Traits ◽

Egg Weight ◽

Partial Dominance ◽

Dominance Variance ◽

Stressful Environment ◽

Model Approach

AbstractHeritabilities, dominance variation and genetic correlations (rpc) among purebred and crossbred performance were estimated for egg production (number of eggs produced between 19 and 25, 26 and 38 and 26 and 54 weeks of age) and egg quality traits (average egg weight, shell strength) in four generations of two nucleus lines of egg-laying chickens and their cross, all reared in similar environments. The within-line genetic parameters were estimated using method R applied to an animal model (approach 1) and tilde-hat approximation to restricted maximum likelihood applied to a sire-dam model (approach 2). The genetic correlation between purebred and crossbred performance as well as the crossbred heritabilities were estimated based on a multivariate sire-dam model accounting for all relationships. For egg numbers and shell strength, the purebred heritabilities were low to moderate (0·12 to 0·42). They were higher when estimated under an additive model (0·25 to 0·51) but, in general, lower than the crossbred heritabilities. For egg weight, the heritabilities were always high (0·6 to 0·7). The ratio of dominance variance to total genetic variance varied between 11 and 36% with approach 1 and 5 and 56% with approach 2, indicating a large partial dominance for egg number traits and shell strength but also the difficulty of accurately estimating the dominance variance. For these traits, the estimates of the correlation between purebred and crossbred performance, rpc, were quite high (0·8 to 0·94) which contradicts the theory that traits with larger dominance and/or difference between purebred and crossbred heritabilities present lower rpc. These high rpc estimates, coupled with the absence of obvious heterosis, indicate little advantage to be gained from use of crossbred data in genetic improvement, where pure lines and crossbreds are reared in a similar non-stressful environment.

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Analysis of (co) variance components and estimation of breeding value of growth and production traits in Dahlem Red chicken using pedigree relationship in an animal model

PLoS ONE ◽

10.1371/journal.pone.0247779 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0247779

Author(s):

U. Rajkumar ◽

L. Leslie Leo Prince ◽

K. S. Rajaravindra ◽

S. Haunshi ◽

M. Niranjan ◽

...

Keyword(s):

Animal Model ◽

Maternal Effects ◽

Variance Components ◽

Egg Production ◽

Genetic Correlations ◽

The Body ◽

Breeding Value ◽

Egg Mass ◽

Residual Variance ◽

Production Traits

Variance and covariance components of growth and production traits were analyzed employing REML animal model to assess the Dahlem Red (PD-3) chicken population for direct additive genetic, maternal effects and to estimate the estimated breeding value (EBV), genetic parameters, genetic trends and rate of inbreeding (ΔF) utilizing seven generation’s data. The generation and hatch had significant (P≤0.01) effect on the body weight at 0 day (BW0), 2 (BW2), 4 (BW4) and 6 weeks (BW6) and shank length at six weeks of age (SL6). The average least squares means (LSM) for BW6 and SL6 were 273.93±0.62 g and 53.97±0.05 mm, respectively. All the production traits were significantly (P≤0.01) influenced by generation and hatch. The average LSM for age at sexual maturity (ASM), egg production up to 40 weeks (EP40) and egg mass up to 40 weeks (EM40) were 168.82±0.25 d, 72.60±0.41 eggs and 4.21±0.07 kg, respectively. Model 5 with additive direct, maternal genetic, maternal permanent environmental and residual variance components was the best for BW0, BW2 and BW4 based on the AIC values obtained in WOMBAT. Model 4 was the best model for BW6, SL6, ASM, EP40 and EM40 with additive direct, maternal permanent environmental and residual variance components. Maternal effects were higher during early age, decreased with age, and remained present until 20 weeks of age. The heritability (h2) estimates were low to moderate in magnitude for all the growth traits and ranged from 0.02±0.03 to 0.19±0.03. The maternal heritability was high at hatch (0.35±0.06), decreased gradually until 4th week (0.02±0.01) and ceased afterwards. The heritabilities of EP40 (0.11±0.03) and EM40 (0.12±0.04) were low. The direct additive genetic correlations (ra) between BW2, BW4, BW6 and SL6 were high and positive (P≤ 0.05). The additive genetic and maternal permanent environmental correlation between EP40 and EM40 were high and positive (P≤ 0.05). The EBV of EM40 was significant (P≤ 0.05) with 0.48 kg/generation in PD-3 chicken at the end of the seventh generation. The EBV of EP40 showed an increasing trend with a genetic gain of 1.87 eggs per generation. The average inbreeding coefficient of the population was 0.019 and average ΔF was 0.007 over the last seven generations of selection. The EBV trends for primary and associated traits showed linear trends in the desired direction and negligible inbreeding.

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Genetic parameters for egg production and egg weight of laying hens housed in single and group cages

Archives Animal Breeding ◽

10.5194/aab-45-501-2002 ◽

2002 ◽

Vol 45 (5) ◽

pp. 501-508 ◽

Cited By ~ 1

Author(s):

V. Nurgiartiningsih ◽

N. Mielenz ◽

R. Preisinger ◽

M. Schmutz ◽

L. Schüler

Keyword(s):

Variance Components ◽

Egg Production ◽

Genetic Parameters ◽

Genetic Parameter ◽

Genetic Correlations ◽

Multiple Trait ◽

Group Cage ◽

Egg Weight ◽

Single Cage ◽

Highly Correlated

Abstract. The present study was conducted to estimate the heritability and genetic correlation of monthly egg production and egg weight of 2 lines White Leghorn hens in single and group cages. A total of 2289 records (line A) and 2596 records (line D) from single cages, 518 and 541 records (for line A and D, respectively) from group cages, were analysed. (Co) variance components of single cage data were analysed using the programme VCE4 applying the REML method and a multiple trait animal model. An EM-algorithm was used to obtain (co) variance components for group cage data. Genetic correlations between single and group cages were analysed using the programme VCE4 based on sire model. Heritability estimates for monthly egg production in single cages ranged from 0.08 to 0.44 (line A); 0.04 to 0.43 (line D) and those for group cages were 0.02 to 0.42 (line A); 0.02 to 0.19 (line D). Egg weight was highly heritable for single and group cages (heritability = 0.25 to 0.54). The genetic correlations between monthly and cumulative egg production were 0.25 to 0.95 (line A); 0.26 to 0.86 (line D) for single cage and 0.24 to 0.84 (line A); 0.26 to 0.96 (line D) for group cage. Cumulative egg production in single cage were highly correlated with those of group cages (0.89 and 0.63, respectively for line A and line D). Single cage records gave higher estimates of genetic parameter than group records. However, the trend of estimates is almost the same. High genetic correlations were found between single- and group cages in most of the production periods.

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Heterosis effect in hybrid laying hens

Biotechnology in Animal Husbandry ◽

10.2298/bah1402303h ◽

2014 ◽

Vol 30 (2) ◽

pp. 303-311 ◽

Cited By ~ 2

Author(s):

P. Hristakieva ◽

M. Oblakova ◽

M. Lalev ◽

N. Mincheva

Keyword(s):

Sexual Maturity ◽

Egg Production ◽

Live Weight ◽

Egg Laying ◽

Production Traits ◽

Egg Weight ◽

Group V ◽

Paternal Line ◽

Group I ◽

Heterosis Effect

The new original egg laying lines T, P and N selected at the Institute of Agriculture - Stara Zagora were used. Hybrid ?? ? ??, ?? ? ?? crosses were obtained and used for paternal line. Thereafter, the following breeding schedule of paternal and maternal lines was applied: Group I - (?????)? ?N?; group ?? - (?????)? ?N?; group ??? - ???N?; and group ?V - ???N?. The production traits of original and hybrid birds were recorded: live weight at the age of 8 and 18 weeks, age of sexual maturity in days, 150 days egg production, average egg weight - at 2-week intervals until end of lay; livability, heterosis effect. The live weights of hybrids at 8 and 18 weeks of age were statistically significantly lower compared to original lines. The values of heterosis for this parameter were negative for all four hybrid combinations. The earliest beginning of egg lay occurred in (?????) ? ?N? (162.08 days of age) and ???N? (163.11 days of age). The relative (%) heterosis for age of sexual maturity of studied hybrid combinations had moderate to low negative values. Average egg weights of hybrids were higher and the values of heterosis - positive for all four groups varying from 0.97% to 1.63%. The average 150 days egg production was lower in purebred lines compared to hybrids. The highest average 150 days egg production was determined in ???N? hybrids - 142 eggs. The heterosis effect for egg production in hybrids was significant.

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Genetic parameters of production and reproduetive traits in on a farm tested Danish Large White and Landrace swine in Greece

Archives Animal Breeding ◽

10.5194/aab-43-287-2000 ◽

2000 ◽

Vol 43 (3) ◽

pp. 287-298

Author(s):

J. Bizelis ◽

A. Kominakis ◽

E. Rogdakis ◽

F. Georgadopoulou

Keyword(s):

Maximum Likelihood ◽

Genetic Correlation ◽

Genetic Parameters ◽

Genetic Correlations ◽

Production Traits ◽

Likelihood Methods ◽

Large White ◽

Reproduction Traits ◽

Maximum Likelihood Methods ◽

Genetic And Phenotypic Correlations

Abstract. Production and reproduetive traits in Danish Landrace (LD) and Large White (LW) swine were analysed by restricted maximum likelihood methods to obtain heritabilities as well as genetic and phenotypic correlations. Production traits were: age, backfat thickness (BT), muscle depth (MD) and the ratio BT/MD, adjusted to Standard bodyweight of 85 kg. Reproduction traits were: number of pigs born (NB) and number of pigs weaned (NW) per sow and parity. Heritabilities for age, BT, MD and BT/MD were 0.60, 0.44, 0.51 and 0.42 for LD and 0.36, 0.44, 0.37 and 0.45 for LW, respectively. Genetic correlations between age and BT were −0.22 in LD and – 0.44 in LW. The genetic correlation between age and MD was close to zero in both breeds. Genetic correlation between BT and MD were −0.36 and −0.25 in LD and LW, respectively. Heritabilities for NB were 0.25 in LD and 0.13 in LW while heritabilities for NW were close to zero in both breeds. Genetic correlation between NB and NW was 0.46 and 0.70 in LD and LW, respectively.

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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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Estimation of genetic parameters and comparison of random regression animal and sire models of production traits in the first three lactations of Iranian Holsteins

Biotechnology in Animal Husbandry ◽

10.2298/bah1402261m ◽

2014 ◽

Vol 30 (2) ◽

pp. 261-279 ◽

Cited By ~ 1

Author(s):

A. Mohammadi ◽

S. Alijani

Keyword(s):

Milk Fat ◽

Genetic Parameters ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

Random Regression ◽

Lactation Period ◽

Production Traits ◽

Environmental Variance ◽

In The Beginning ◽

Residual Variances

This study was conducted to compare of random regression (RR) animal and sire models for estimation of the genetic parameters for production traits of Iranian Holstein dairy cows. For this purpose, the test day records were used belonged to first three lactations of cows and for, milk, fat and protein yields traits where, collected from 2003 to 2010, by the national breeding center of Iran. The genetic parameters were estimated using restricted maximum likelihood algorithm. To compare the model, different criterion -2logL value, AIC, BIC and RV were used for considered traits. Residual variances were considered homogeneous over the lactation period. Obtained results showed that additive genetic variance was highest in the beginning and end lactation and permanent environmental variance was highest in beginning of lactation than other lactation period. Heritabilities estimate for milk, fat and protein yields by RR animal and sire models were found to be lowest during early lactation (0.05, 0.04 and 0.07; 0.05, 0.19 and 0.13; 0.14, 0.19 and 0.15, for milk, fat and protein yields and in first, second and third lactation respectively). However, estimated heritabilities during lactation did not vary among different order Legendre polynomials, and also between RR animal and sire models. The variation in genetic correlations estimate in the RR animal and sire models was larger in the first lactation than in the second and third lactations. Thus, based on the results obtained, it can be inferred that the RR animal model is better for modeling yield traits in Iranian Holsteins.

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