BREEDING VALUE ACCURACY DEPENDED ON:
- Data quality of traits measured on animals
- Uniform and controlled environment (no preferential treatment)
- Information on relatives and number of progeny
DATA QUALITY OF TRAITS MEASURED ON ANIMALS
When you measure data on animals, it is important to:
- Use a well calibrated weighing scale
- For ultrasound scanning
– Animal position
– Scanning method
- Measure at the right time
– Birth weight (first 24h)
– Age at 50d and 100d weighing
- Identify the fostered and bottle-fed lambs
- Collect number born and raised with accuracy
- Etc…
This importance of data collection is often underestimated by breeders. The accuracy of breeding values is based on quality of pedigree and animal performance records.
Uniform and controlled environment
(no preferential treatment)
Environment effects on animals performance are not pass onto the progeny. You need to have a good control on environment effects using appropriate management groups.
The breeding environment should be controlled and homogeneous.
How to remove environment effects on performance?
By comparing together animals raised:
- In the same period of time
- In the same environment (same management)
– Feeding
– Management
– Barn
– Etc…
The solution is:
MANAGEMENT GROUP
A winning strategy would be to synchronize the lambings to have the maximum number of lambs evaluated under the same conditions (same management group)
Some tips to create better management groups
Group your lambings
- Minimize age difference within the group
- Decrease adjustments between lambs
- Measure growth within the same environment
- Maximum number of lambs per sex (minimum of 10 lambs per sex)
Breeding management
- Aim at least 3 different rams / group (minimum of 2 rams / group)
- Aim similar number of mates / ram
- Use the GenOvis mating planner to allocate different genetic level of the ewes to each ram.
Information on relatives and number of progeny
Those affect EPD accuracy
Important to record as much information as possible, mostly for traits having low heritability (e.g. maternal traits). Commercial flocks related to purebred flock add records within the database and increase the accuracy of the breeding values.