Quantitative Biology

1802 Submissions

[2] viXra:1802.0341 [pdf] submitted on 2018-02-24 09:48:23

Genetic Groups and the Feasibility of Reference Sire Schemes

Authors: Stephen P. Smith, Robert D. Scarth, Bruce Tier
Comments: 8 Pages.

A method of measuring linkage in sire reference schemes is described. The method consists of determining estimability and prediction error variance for linear contrasts when the assumed animal model includes genetic groups. Base animals in a herd are assigned a common genetic group and different herds correspond to different genetic groups. The set of linear contrasts used to determine linkage is the set of group differences. Groups differences can be scrutinized using a simplified lease-squares analysis.
Category: Quantitative Biology

[1] viXra:1802.0057 [pdf] submitted on 2018-02-05 14:52:22

Estimating Genetic Parameters in a Dominance Model that Includes Inbreeding

Authors: Stephen P. Smith, Asko Mäki-Tanila
Comments: 21 Pages.

A dominance model is described coming with inbreeding, and five genetic parameter plus the environmental variance. The linear model is specified by the phenotypic equations and the mid-parent equations. They are placed in an indefinite system that is highly sparse, not the mixed model equations. From this system the augmented matrix K is built that is symmetric and indefinite, leading to restricted maximum likelihood. Likelihood evaluation follows from the factorization of K, and various sparse matrix tools are described for maximizing the likelihood. The method is used to estimate the six parameters for 2706 egg-laying hens that were part of a selection experiment.
Category: Quantitative Biology