The purpose of this trial, carried out under commercial conditions, was to quantify any economic benefit of High Index recorded tups in terms of their value…
- as sires of slaughter lambs
- as sires of breeding ewes
The 'trial' farms
- had a commitment to the trial
- collected all the data required
- bred and finished Blackface, North Country Cheviot, or Texel Cross lambs, with the majority of the finished lambs being sold deadweight.
- retained home bred ewe lambs as flock replacements
- held three meetings per year to share the flock information with the "Flock Group" of 12-15 breeders in their area
- attended a lamb grading workshop to ensure that selection is as accurate as possible
Four tups were supplied to each farm - two with high EBVs and two with low EBVs for the following traits:
- Muscle depth
- Fat depth
- Litter size
- Maternal Ability
Three groups of ewes of a similar breed type and age profile were selected at random and identified within the flock.
The High and Low Index Rams tupped a group each and the third group was tupped by rams with unknown genetic potential (i.e. tups already on the farm and selected by eye).
After tupping the groups ran together and were reated in the same way. Lambs born to all three sire groups were tagged with a unique number and the following data recorded :
- Sire of lamb (High, Low, or non recorded, or, if possible, each individual sire)
- Sex of lamb & Date of birth
- Birth type (single, twin, or triplet)
- A note if reared by a foster dam.
Slaughter lambs were weighed prior to leaving the farm.
The abattoir recorded each lamb's individual tag.
Copies of the slaughter results were sent to Signet.
When all the lambs in each group were slaughtered a comparative analysis was carried out.
Details of the trial and the location of the farms were posted on this web site.