Article by Steve & Deb Milne, RHAg
At the recent national conference, Dr Jason Trompf spoke about the increasing use of White Suffolks as maternal sires. However, he also bemoaned the fact that only a small number of White Suffolk flocks record enough information to have ASBVs for reproduction traits. Reproduction breeding values for Number of Lambs Born (NLB) and Number of Lambs Weaned (NLW) on the sire indicate how that sire’s daughters are going to perform. Hence when you record reproduction on the females it contributes to the breeding values of their sires.
So, what can you do to improve your repro data?
Essentially there a few key pieces of data required, all of which will assist you in being linked for reproduction and hopefully get ASBVs for NLB and NLW. This information can be recorded in software’s in the mating section.
- Identify Dry Ewes
In order to determine ewes that are superior for fertility we must know about the ewes that are DRY. The easiest way to do this is to enter pregnancy scan results. For Dry ewes a pregnancy scan result is 0 if scanning for multiples and “D” if scanning wet/dry.
- Dead at birth Lambs (DABs)
DABs are lambs born dead (lambs that have not been tagged – if they were tagged and then died, leave them with their tag number). A DAB is recorded as 23-OFLK-YEAR-DAB001, etc. and is included in the database in the same way as a live lamb. You still record DOB RT and BT and a BWT if you measure this on these lambs. Recording DABs assists not only repro data. If you are recording birth weight, it stands to reason that recording the birth weight of a dead twin, rather than only the live one, is important in the calculation of birth weight ASBVs. But even if you are not recording birth weight, if you have a DAB lamb record it!
Dam Pedigree
In order to get into the reproduction analysis, you must be recording dam pedigrees.
This is because we must know which lambs belong to what ewes to know how she is performing.
The reproduction analysis is currently being upgraded and new research breeding values will be released with analysis changes in May. These upgrades will include values for the component traits of reproduction; fertility, litter size and ewe rearing ability (lamb survival attributed by the ewe). In order to receive these breeding values Sheep Genetics, require little more information than you should already have - it just needs to be submitted!
The checklist below shows the information which should be recorded.
At a minimum you should record:
- Ram in, Ram out dates
- Joining group
- Identify dry ewes
- Pregnancy scan (preferably multiples)
- Scanning group
And it is possible to record:
- Ewe weight (at joining)
- Ewe condition score (with the above weight)
Then at lambing take records on:
- Lamb date of birth
- Birth weight
- Dam pedigree
- Birth type and rear type
- DAB lambs
- Lambing group
And possibly
- Maternal Behaviour Score (MBS)
Then at weaning
- Update Rear Type
Sheep Genetics are targeting the use of mating modules because they are trying to develop a better reproduction analysis, so if able to, use your mating module in your respective software.
If you need more information about recording reproduction traits contact Clara Collison at Sheep Genetics on 02 8055 1824 or ccollison@mla.com.au.
