Agriculture, farming, animal husbandry, animal health, disease, Facial Eczema, prevention, breeding, genetics, FE resistant rams, buying rams, advice, recommendations
By Dr Clive Dalton
Original 1991 information written by Dr Barry Smith and Dr Neale Towers, Ruakura Agricultural Research Station, Hamilton, New Zealand.
'Piquet Hill' FE-resistant 2th rams, selected for FE resistance for 27 years
19. Facial Eczema: (Sheep). Breeding. Buying FE resistant rams.
- Start breeding FE resistance into your flock. Why? Because it is a permanent gain, adding value to your flock and makes other annual precautions easier and less critical.
- Tolerance to FE is strongly inherited. About 40 percent of the differences in resistance to FE seen between individual animals is due to their sire.
- Therefore progress in selecting and breeding more resistant sheep can be rapid, and significant gains can be made in only a few years of concentrated selection.
- But remember always that breeding for resistance is a long term commitment - it will not provide an overnight solution to your FE problems.
- Work in the Ruakura Resistant flock shows that the proportion of animals able to withstand a standard toxin dose can be increased by at least 2.5 to 3.5 percent each year.
- AgResearch operates a performance testing service called RAMGUARD to identify the most FE resistant rams amongst those tested by the breeders tested mob.
- Ram breeders using the RAMGUARD FE testing service for six years have doubled the resistance level of their flocks.
- Begin buying your rams from a breeder selecting for FE resistance using the RAMGUARD FE resistance testing service.
- If your current ram breeder is not testing for FE resistance either:
- (1). Persuade him/her to start testing.
- (2). Change to a breeder who is.
- Buy only from breeders who are selecting for FE resistance.
- You should be consistent in this. You can lose the gains you have made if you bring in susceptible sheep from untested flocks.
- Select a ram breeder with sheep suited to your type of country, and with the conformation and production traits you want in your flock. Make sure he/she is committed to doing a good job selecting for FE resistance and is not just "window-dressing" to secure ram sales.
- It is not sufficient to hear the breeder say he is testing for FE resistance. You have to check out the programme and be sure that the rams you buy share the resistance that has been developed.
Check the following points:
- The number of rams tested and the number used as sires. The more rams tested and the smaller the percentage used as sires the faster progress should be.
- Whether the breeder has used RAMGUARD to identify the most resistant 5, 10, 20 or 50 percent of the rams tested.
- Breeders using rams from the top 5 percent will make faster progress than those selecting rams from the top 50 percent.
- Check that only rams from the top resistant group are used as sires in the breeder’s flock.
- Using rams from low on the FE resistance ranking because they have high wool weights etc will slow down progress.
- Check what priority the breeder places on FE resistance to see if it matches your priorities. Placing a high priority on FE may slow progress for the other traits and vice versa.
- How many ram crops have been tested. So long as a sound selection programme has been established, the longer the breeder has been testing the further he will have progressed.
- The number of breeders with established FE selection programmes is relatively small at present so your choice of breeders may be limited to those who have only recently started selection for FE resistance.
- But remember, how well a breeder is selecting for FE resistance is more important than how long he has been testing.
- A new breeder testing a large number of rams and only using the most resistant rams will quickly overtake a breeder who tests only a few rams and/or uses rams from low on the resistance ranking list.
- Above all make sure that the rams you buy are sired by tested facial eczema resistant rams.
- Having found a breeder in whom you have confidence, stick with him/her. Your progress will parallel their flock with you trailing by 2 or 3 seasons.
- Be prepared to pay a premium for rams from breeders running a sound FE selection programme. You will benefit from more resistant stock, better production and fewer losses. The breeder has high testing costs to meet in selecting resistant sires.
This material is provided in good faith for information purposes only, and the author does not accept any liability to any person for actions taken as a result of the information or advice (or the use of such information or advice) provided in these pages.