What is Deer Select?

What is Deer Select?

Deer Select is a database for storing pedigree records (see Matching calves and dams) and trait data collected from performance recorded animals.

Deer Select operates under SIL (Sheep Improvement Limited).   
SIL’s genetic engine performs analyses using the pedigree and trait data along with heritabilities and genetic correlations.  This analysis is performed using Best Unbiased Linear Predictions (BLUP) to provide-

  • breeding values (BVs), which are estimates and so sometimes referred to as estimated breeding values (eBVs); and
  • estimates of the accuracy of each BV.

The BLUP analysis is designed to perform a genetic analysis; that is to remove the environmental effects and allow comparison of individuals based on their genetic merit.
On DEERSelect the BVs provided are calculated across the different herds of red deer and separately across the different herds of wapiti, so that animals from one herd can be directly compared with those of another after environmental effects have been accounted for.

Environmental effects and mob management
Environmental effects are generally management effects that may affect an individual differently if it was run on a different paddock. Environmental effects include-

  • feed quality
  • feed quantity
  • competition
  • parasite or disease challenge
  • shelter
  • shade
  • disturbance
  • drinking water

It is impossible to know, let alone measure, what environmental effect may be influencing different mobs across different paddocks, but it is easy to account for them in the genetic analysis by recording the mob in which a particular deer is run.
Deer Select uses mob information to create ‘contemporary’ groups.  Contemporary groups are built up over the deer’s lifetime, but are especially important in the first 12 months.
The contemporary group is a group of individuals who have been in the same environment (mobs) their whole life and, therefore, their performance can be directly (genetically) compared against each other.  Ideally mob sizes should be maximised as this improves the quality of the data used by Deer Select to evaluate environmental effects and splitting of mobs minimised. This approach will provide the largest possible contemporary groups.
Sex is a special case as males and females are never directly compared in Deer Select.  Accordingly, for genetic recording purposes, the best mob split is by sex.