Breeding sheep to eliminate dags and worms. 5.

By Dr Clive Dalton

PART 5

Two-tooth ewes from the A team nucleus

• Now as two-tooths bred from the A team nucleus ewes, they should look a picture due to the intense selection pressure put on them up to now.
• Apart from the odd sample to monitor progress, it’s not worth doing any more FECs, but keep on ruthlessly culling any that get daggy and don’t clear up quickly.
• There would be no harm in doing a FCS now and again to check on any that are not measuring up, especially those getting daggy and not drying up fast.
• Cull any that develop problems like footrot.
  

Planning the two-tooths’ mating
Decision needed: What rams are you going to join with these top two-tooths? They deserve very special consideration after all the work you’ve put into them.

Ram options

Option 1:

Stud breeders rams at pubic auction but few FEC records and no dag data.

• Contact your nearest consultant from Sheep Improvement Ltd (SIL) by phoning 0800-745-435, or Email "mailto:help@sheepimprovement.co.nz" help@sheepimprovement.co.nz
• Ask which breeders have rams for sale with WormFEC™ and Dag Score BVs.
• Take care to check the records and ask the breeder how many rams have been tested and how this was done, as despite the SIL WormFEC™ protocol in the Breeders’ Manual (1994), some breeders have developed a few variations of their own.
• FCS is not accepted by SIL as a correction for FEC. And in any case, the rams will all have been drenched regularly and recently, so you won’t be able to get a true ‘drug-free’ FCS assessment.
• Beware that breeders may advertise that they are breeding for worm resistance or even worm resilience, but their programmes will need questioning.

Lab FEC raw data on rams at a sale - a very rare feature.
The FECs were not being used in an index.

Option 2:

• Failing any success with SIL breeders, the next option is to look at any old sires you have on the farm purchased previously from SIL breeders.
• This could surprise you or shock you - to see what you have spent money on (in all innocence) in previous seasons.
  
• Their mature (genetic) immunity against dags and worms should have been fully developed – if they have any. It would be worthwhile having a look.
• Make sure they have not been drenched for at least two months (preferably three) and first check their FCS. It’s not worth wasting $5 on a FEC if a ram is a scourer.
• Any like this need to be used as terminal sires as you’ll be dagging their progeny for the next five years at least.
• For the marblers or hand grenaders, get a FEC done.
• Don’t contemplate using any animal with a FEC over 500 epg and zero should be a better target.
  

Option 3:
This is the obvious choice - to use your own rams, bred in the A team nucleus flock, and Pathway 2 describes this.