Deer Select is a database and evaluation pedigree records (see Matching calves and dams) and trait data collected from performance recorded animals. It corrects for known environmental effects on performance to estimate the genetic component which is passed on to progeny.
For more information on Deer Select contact the Deer Industry office on 04 473 4500 or refer to DINZ contacts >>
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-
- Estimated breeding values (BVs)
- Estimates of the accuracy of each BV – based on the amount of information to calculate the BV
- Key performance Indexes – amalgamates trait (Growth, Meat etc) BVs and their economic value to a standardised deer production system into a single value expressed in cents or dollars per hind mated.
The BLUP analysis accounts for environmental effects and estimates the genetic merit of individuals for recorded traits. Indexes and breeding values for genetically connected herds can be compared across herd within species- Red or Wapiti. Within herd values are only benchmarked relative to animals in those herds.
Deer Select is moving to an across breed single evaluation.
Environmental effects and mob management
Environmental effects are generally management effects that may affect impact on an animal’s performance and should be accounted for in the evaluation.
Environmental effects include-
- Age of dam – first calvers generally have lower birth weight and lower lactation than mixed age hinds impacting on progeny weaning weights
- Date of birth – there can be up to 6 weeks difference in birth dates.
- Mob – different mobs may be advantaged or disadvantaged due to differing feed quality, quantity, parasite challenge, shelter, shade, exposure etc which can impact performance but is not genetic.
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. For animals in different mobs – a correction factor needs to be calculated – this is based on the relative performance of progeny of common sires across groups. E.g. simplistic example of correction factor - In Mob 1 on better feed the progeny of Sire A averaged 65kg at weaning, progeny of sire 123 averaged 60kg in Mob 2, - mob effect equates to 5kg. Adding 5 kg to all animals in Mob 2means they can be directly compared with animals in mob 1. Date of birth and age of dam effects would also be included in the correction calculation.
Ideally mob sizes should be maximised as this improves the quality of the data used by Deer Select to evaluate environmental effects, combining of whole mobs rather splitting a mob across multiple mobs is preferred. This approach will provide the largest possible contemporary groups and improve across mob correction accuracy.
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.
Information on Deer Select is available in a convenient DINZ Deer Fact sheet (September 2015). Download your own copy here >>