J. H. Julius van der Werf

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Long range phasing (LRP) is a fast and accurate rule based method which uses information from both related and unrelated individuals by invoking the concepts of surrogate parents and Erdös numbers (Kong et al., 2008). Recursive long range phasing and long haplotype imputation (RLRPLHI; Hickey et al., 2009) is an extended LRP algorithm with increased(More)
Biosciences Research Division, Department of Primary Industries, Bundoora 3083, Victoria, Australia, Cooperative Research Centre for Sheep Industry Innovation, Armidale 2351, NSW, Australia, Animal Genetics and Breeding Unit (AGBU), Armidale 2351, NSW, Australia School of Environmental and Rural Science, University of New England, Armidale 2351, NSW,(More)
Selection strategies for the genetic improvement of reproductive performance of sheep in Australia are discussed in the context of current and emerging industry practice. The predicted rates of gain in reproductive rate are compared with varying amounts of pedigree and performance records of relatives. The paper also considers the merits of exploiting(More)
Segregation analysis indicated the presence of major genes for three post-weaning traits; weight, eyemuscle depth and C fat, within a Texel based dataset obtained from LAMBPLAN. The effect of expressing one paternal copy (in phenotypic standard deviation units in brackets) was 2.71 kg (0.48) for weight, 1.05mm (0.50) for eye-muscle depth and -0.42mm (0.60)(More)
Implementation of genomic selection in sheep breeding provides a number of challenges, compared to dairy cattle, because of the higher genetic diversity between and within sheep breeds, the cost of maintaining reference populations and the limited ability of individual breeders to invest in genotyping. Within this study, we compare theoretical and realized(More)
CRC for Sheep Industry Innovation and the University of New England, Armidale, NSW 2351 NSW Department of Primary Industries, Trangie, NSW 2823 Animal Genetics and Breeding Unit*, University of New England Armidale, NSW 2351 Department of Agriculture and Food WA, South Perth, WA 6150 Department of Primary Industries, Werribee, Victoria 3030 Present address:(More)
Three approaches were used to detect genotype x environment (GxE) interaction and estimate heritabilities for “number of lambs born” (NLB) in Merino progeny of the Sheep CRC Information Nucleus Flock. Approaches included a univariate model, fitting site x sire interaction as a random effect and a bivariate model that treated NLB expressed at high and low(More)
Reproduction traits are important but difficult to improve in sheep because they are lowly heritable and are recorded later in life. Genomic information can be used for genomic prediction of breeding values to increase the accuracy of selection. Alternatively, genomic information can be used to identify recessive lethal mutations, which cause embryonic(More)
Genomic selection is a new DNA based method of selecting animals for breeding. The test reveals DNA differences between animals for thousands of genetic markers. Prediction of an animal’s genetic merit is based on DNA comparison with a group of reference animals with trait measurements as well as a DNA profile. A sustainable use of genomic selection by(More)
CRC for Sheep Industry Innovation, University of New England, Armidale, NSW 2351 Industry & Investment NSW, Trangie Agricultural Research Centre, Trangie, NSW 2823 Department of Agriculture and Food WA, South Perth, WA 6150 Department of Primary Industries, Werribee, Victoria 3030 Present address: Food and Nutritional Sciences, CSIRO, Werribee, Victoria(More)