Journal of Animal Breeding and Genetics This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

A molecular analysis of the patterns of genetic diversity in local chickens from western Algeria in comparison with commercial lines and wild jungle fowls
The objectives of this study were to characterize the genetic variability of village chickens from three agro‐ecological regions of western Algeria: coastal (CT), inland plains (IP) and highlands (HL), to reveal any underlying population structure, and to evaluate potential genetic introgression from commercial lines into local populations. A set of 233 chickens was genotyped with a panel of 23 microsatellite markers. Geographical coordinates were individually recorded. Eight reference populations were included in the study to investigate potential gene flow: four highly selected commercial pure lines and four lines of F...
Source: Journal of Animal Breeding and Genetics - March 17, 2015 Category: Genetics & Stem Cells Authors: F. Z. Mahammi, S. B. S. Gaouar, D. Laloë, R. Faugeras, N. Tabet‐Aoul, X. Rognon, M. Tixier‐Boichard, N. Saidi‐Mehtar Tags: Original Article Source Type: research

Genetic parameters for different growth scales in GIFT strain of Nile tilapia (Oreochromis niloticus)
Summary Body weight, length, width and depth at two growth stages were observed for a total of 5015 individuals of GIFT strain, along with a pedigree including 5588 individuals from 104 sires and 162 dams was collected. Multivariate animal models and a random regression model were used to genetically analyse absolute and relative growth scales of these growth traits. In absolute growth scale, the observed growth traits had moderate heritabilities ranging from 0.321 to 0.576, while pairwise ratios between body length, width and depth were lowly inherited and maximum heritability was only 0.146 for length/depth. All genetic ...
Source: Journal of Animal Breeding and Genetics - March 6, 2015 Category: Genetics & Stem Cells Authors: J. He, H. Gao, P. Xu, R. Yang Tags: Original Article Source Type: research

Random regression test day models to estimate genetic parameters for milk yield and milk components in Philippine dairy buffaloes
Summary Heritabilities and genetic correlations for milk production traits were estimated from first‐parity test day records on 1022 Philippine dairy buffalo cows. Traits analysed included milk (MY), fat (FY) and protein (PY) yields, and fat (Fat%) and protein (Prot%) concentrations. Varying orders of Legendre polynomials (Legm) as well as the Wilmink function (Wil) were used in random regression models. These various models were compared based on log likelihood, Akaike's information criterion, Bayesian information criterion and genetic variance estimates. Six residual variance classes were sufficient for MY, FY, PY and ...
Source: Journal of Animal Breeding and Genetics - March 2, 2015 Category: Genetics & Stem Cells Authors: E.B. Flores, J. Werf Tags: Original Article Source Type: research

A retrospective analysis of allele frequency changes of major genes during 20 years of selection in the Italian Large White pig breed
In this study, we investigated whether a selection programme based on boar genetic evaluation obtained with a classical BLUP animal model can change allele frequencies in a pig population. All Italian Large White boars born from 1992 to 2012 with estimated breeding value reliability >0.85 (n = 200) were selected among all boars of this breed. Boars were genotyped with markers in major genes (IGF2 intron3‐g.3072G>A, MC4R p.D298N, VRTN PRE1 insertion, PRKAG3 p.I199V and FTO g.276T>G). Genotyping data were analysed grouping boars in eight classes according to their year of birth. To evaluate the influence of time...
Source: Journal of Animal Breeding and Genetics - March 1, 2015 Category: Genetics & Stem Cells Authors: L. Fontanesi, G. Schiavo, E. Scotti, G. Galimberti, D.G. Calò, A.B. Samorè, M. Gallo, V. Russo, L. Buttazzoni Tags: Original Article Source Type: research

Assessment of bagging GBLUP for whole‐genome prediction of broiler chicken traits
Summary Bootstrap aggregation (bagging) is a resampling method known to produce more accurate predictions when predictors are unstable or when the number of markers is much larger than sample size, because of variance reduction capabilities. The purpose of this study was to compare genomic best linear unbiased prediction (GBLUP) with bootstrap aggregated sampling GBLUP (Bagged GBLUP, or BGBLUP) in terms of prediction accuracy. We used a 600 K Affymetrix platform with 1351 birds genotyped and phenotyped for three traits in broiler chickens; body weight, ultrasound measurement of breast muscle and hen house egg production. ...
Source: Journal of Animal Breeding and Genetics - March 1, 2015 Category: Genetics & Stem Cells Authors: R. Abdollahi‐Arpanahi, G. Morota, B.D. Valente, A. Kranis, G.J.M. Rosa, D. Gianola Tags: Original Article Source Type: research

Genetic heteroscedasticity of teat count in pigs
Summary The genetic improvement in pig litter size has been substantial. The number of teats on the sow must thus increase as well to meet the needs of the piglets, because each piglet needs access to its own teat. We applied a genetic heterogeneity model to teat counts in pigs, and estimated a medium heritability for teat counts (0.35), but found a low heritability for residual variance (0.06), indicating that selection for reduced residual variance might have a limited effect. A numerically positive correlation (0.8) was estimated between the breeding values for the mean and the residual variance. However, because of the...
Source: Journal of Animal Breeding and Genetics - February 1, 2015 Category: Genetics & Stem Cells Authors: M. Felleki, N. Lundeheim Tags: Original Article Source Type: research

Genetic analysis of river, swamp and hybrid buffaloes of north‐east India throw new light on phylogeography of water buffalo (Bubalus bubalis)
This study analysed buffaloes from north‐east India and compared their nuclear and mitochondrial DNA variations with buffaloes of mainland India, China, Mediterranean and South‐East Asia. Microsatellite genotypes of 338 buffaloes including 210 from six north‐east Indian buffalo populations and three mainland Indian breeds were analysed to evaluate their genetic structure and evolutionary relationships. Phylogenetic analysis and multidimensional scaling plot of pairwise FST revealed the clustering of all swamp‐type buffaloes of north‐east India with Lower Assamese (significantly hybrid type) buffaloes in one plane...
Source: Journal of Animal Breeding and Genetics - February 1, 2015 Category: Genetics & Stem Cells Authors: B.P. Mishra, P.K. Dubey, B. Prakash, P. Kathiravan, S. Goyal, D.K. Sadana, G.C. Das, R.N. Goswami, V. Bhasin, B.K. Joshi, R.S. Kataria Tags: Original Article Source Type: research

Additive and epistatic genome‐wide association for growth and ultrasound scan measures of carcass‐related traits in Brahman cattle
This study considers analytical methods that detect statistical interactions between pairs of loci. We investigated a three‐stage modelling procedure: (i) a model without the SNP to estimate the variance components; (ii) a model with the SNP using variance component estimates from (i), thus avoiding iteration; and (iii) using the significant SNPs from (ii) for genome‐wide epistasis analysis. We fitted these three‐stage models to field data for growth and ultrasound measures for subcutaneous fat thickness in Brahman cattle. The study demonstrated the usefulness of modelling epistasis in the analysis of complex traits ...
Source: Journal of Animal Breeding and Genetics - February 1, 2015 Category: Genetics & Stem Cells Authors: A.A. Ali, M.S. Khatkar, H.N. Kadarmideen, P.C. Thomson Tags: Invited Review Source Type: research

Sustainable dairy cattle selection in the genomic era
Summary Genomic selection offers considerable flexibility to increase genetic trends in dairy cattle breeding. It is also an opportunity for more sustainable breeding, in terms of breeding goal and genetic variability. With a shorter generation interval, there is a big risk of increasing inbreeding if semen dissemination policy of elite bulls is not changed. However, using a large number of young bulls as service bulls and bull sires is a solution for both maximizing genetic trend while reducing inbreeding trend. Female genotyping is a key challenge for within‐herd selection but, more importantly, for selection of new tr...
Source: Journal of Animal Breeding and Genetics - February 1, 2015 Category: Genetics & Stem Cells Authors: D. Boichard, V. Ducrocq, S. Fritz Tags: Invited Review Source Type: research

Estimates of genetic variance and variance of predicted genetic merits using pedigree or genomic relationship matrices in six Brown Swiss cattle populations for different traits
We examined a range of traits in six populations amounting to 173 population‐trait combinations. A main aim was to determine how using different relationship matrices affect variance estimation. We calculated ratios between different types of estimates and analysed the impact of trait heritability and population size. The genetic variances estimated by REML using a genomic relationship matrix were always smaller than the variances that were similarly estimated using a pedigree‐based relationship matrix. The variances from the genomic relationship matrix became closer to estimates from a pedigree relationship matrix as ...
Source: Journal of Animal Breeding and Genetics - February 1, 2015 Category: Genetics & Stem Cells Authors: A. Loberg, J. W. Dürr, W.F. Fikse, H. Jorjani, L. Crooks Tags: Original Article Source Type: research

Genetic conditions of joint Nordic genetic evaluations of lifetime competition performance in warmblood sport horses
Summary Breeding programmes for warmblood sport horses are similar in the Nordic countries Sweden, Denmark, Finland and Norway, and stallions of same origin are used. The aim was to investigate whether a joint Nordic genetic evaluation based on lifetime competition performance is feasible and beneficial for breeding competitive sport horses in the Nordic countries. Results for almost 45 000 horses in show jumping and 30 000 horses in dressage were available. The larger populations in Sweden and Denmark contributed with 85% of the results. Heritabilities and genetic correlations between performances in the different count...
Source: Journal of Animal Breeding and Genetics - February 1, 2015 Category: Genetics & Stem Cells Authors: Å. Viklund, S. Furre, S. Eriksson, O. Vangen, J. Philipsson Tags: Original Article Source Type: research

Polynomial order selection in random regression models via penalizing adaptively the likelihood
Summary Orthogonal Legendre polynomials (LP) are used to model the shape of additive genetic and permanent environmental effects in random regression models (RRM). Frequently, the Akaike (AIC) and the Bayesian (BIC) information criteria are employed to select LP order. However, it has been theoretically shown that neither AIC nor BIC is simultaneously optimal in terms of consistency and efficiency. Thus, the goal was to introduce a method, ‘penalizing adaptively the likelihood’ (PAL), as a criterion to select LP order in RRM. Four simulated data sets and real data (60 513 records, 6675 Colombian Holstein cows) were em...
Source: Journal of Animal Breeding and Genetics - January 27, 2015 Category: Genetics & Stem Cells Authors: J.D. Corrales, S. Munilla, R.J.C. Cantet Tags: Original Article Source Type: research

Resemblance between two relatives – animal and plant breeding
(Source: Journal of Animal Breeding and Genetics)
Source: Journal of Animal Breeding and Genetics - January 26, 2015 Category: Genetics & Stem Cells Authors: C.C. Schön, H. Simianer Tags: Editorial Source Type: research

A method to approximate the inverse of a part of the additive relationship matrix
The objective of this study is to present a modification of the SP algorithm (RSP algorithm) and to assess its use in approximating when the actual is dense. The RSP algorithm sets up a restricted sparsity pattern of by limiting the pedigree search to a maximum number of searched branches. We have tested its use on four different simulated genotyped populations, from 10 000 to 75 000 genotyped animals. Accuracy of approximation is tested by replacing the actual by its approximation in an equivalent mixed model including only genotyped animals. Results show that limiting the pedigree search to four branches is enough ...
Source: Journal of Animal Breeding and Genetics - December 1, 2014 Category: Genetics & Stem Cells Authors: P. Faux, N. Gengler Tags: Original Article Source Type: research

Genetic parameters for litter size, piglet growth and sow's early growth and body composition in the Chinese–European line Tai Zumu
Summary Genetics of piglet growth in association with sow's early growth and body composition were estimated in the Tai Zumu line. Piglet and sow's litter growth traits were calculated from individual weights collected at birth and at 3 weeks of age. Sow's litter traits included the number of piglets born alive (NBA), the mean piglet weight (MW) and the standard deviation of weights within the litter (SDW). Sow's early growth was measured by the age at 100 kg (A100), and body composition included backfat thickness (BF100). A main objective of this study was to estimate separately the direct genetic effect (d) and the mat...
Source: Journal of Animal Breeding and Genetics - November 26, 2014 Category: Genetics & Stem Cells Authors: M. Banville, J. Riquet, D. Bahon, M. Sourdioux, L. Canario Tags: Original Article Source Type: research