Best Breeding Practices for the Australian Stumpy Tailed Cattle Dog
The recognised inherited diseases in the Stumpy at present include the following:-
- Deafness
- Hips and elbows
- Eyes – PRA (PRCD),
- Eyes – other conditions.
- Deafness– as a breed that is born white, deafness and our awareness of the problem must remain constant. It is recommended that BAER testing of all puppies between the ages of 6-8 weeks is done to sort out the hearing from the deaf puppies but more importantly the unilaterals.Unilaterals – it has been proven that breeding with unilaterals results in a much higher percentage of deaf puppies. These dogs are perfectly fine as pets or working dogs in the general world as they can hear, but they should ideally not be bred from.
It is recommended that all puppies are BAER tested prior to sale.
- Hips and Elbows – as the Stumpy is a working breed it is essential that the dog be sound for all types of work. The hips are improving and the current breed average would be around 10. Elbows generally are good but the odd case of arthritis in the elbows does occur. Ideally one should not double up on either poor hips or poor elbows. The only way to avoid this is by X raying breeding stock at around 12-15 months ie. before breeding age. This then allows breeders to make sensible breeding choices in light of the results.
It is recommended that all breeding stock be X rayed for hip and elbow dysplasia assessment before breeding.
3. Eyes PRA(PRCD) has been confirmed in both the Cattle Dog and the Stumpy. There is a definitive DNA test for the condition such that one can breed safely without the fear of producing affected puppies.
Up until the recent development of a range of genetic tests for recessively inherited forms of PRA, it has been impossible to predict the onset of progressive retinal failure and inevitable vision loss, any time from two years of age in some cases, through to eight years in most affected breeds.
As for any autosomal recessive trait, the genetic status of individual animals must be able to be determined by DNA test to be either affected (homozygous affected), clear (normal ie. homozygous unaffected) or a ‘carrier’, the significance of which may vary (see below). Depending on the type of PRA, the actual genetic status of an individual (adult or puppy) can now be confirmed at a very early age without having to wait until any visual deficit becomes obvious.
The inheritance mode for PRA in the great majority of affected breeds operates as a simple autosomal recessive, with the heterozygous unaffected or ‘carrier’ state being clinically unaffected, i.e. its retinal vision remains normal throughout life.
Advice on breeding with PRA(PRCD)
PRA (Recessive inheritance pattern)
Australian Cattle Dogs and Australian Stumpy tail Cattle Dogs (prcd);
The following breeding advice is offered in relation to recessive type PRA :
- Before a mating is agreed and assuming no prior test results are available, designated samples (blood or cheek swabs) from both mating partners should be submitted for DNA testing through an approved laboratory, with identities of each confirmed by microchip against the registration records. An exception arises when frozen semen is to be used, from a sire that is deceased, overseas or otherwise unable to be sampled.
- Ideally, at least one parent of a planned litter should be confirmed as homozygous unaffected or ‘Clear/Normal’ for the recessive form of PRA, by DNA testing or by parentage.
- Breeding from homozygous affecteds is not recommended and may be carried out only as part of a planned long term breeding program. An affected animals (DNA test) should only be mated only to a clinically normal animal confirmed ‘Clear/Normal’ by DNA test or parentage. All resulting pups will be heterozygous unaffected ‘Carriers’ and their registration records must be so endorsed.
- Acceptable matings for any breed where recessive PRA has been described are Clear to Clear, Clear to Carrier or Clear to Affected (see above). Clear to clear matings do not require individual pups to be DNA tested as they are already clear by parentage. Clear to Carrier matings will not result in any affected pups but will produce a proportion of carriers, which need to be identified. Any puppy retained or sold for breeding purposes should undergo DNA testing to separate the clears from the carriers, allowing each pup’s registration record to be endorsed with its genetic status.
- Affected to Affected matings should not occur.
- Carrier to Carrier matings are not recommended and all progeny must be DNA tested prior to sale. Any confirmed affected individuals must be desexed before sale, also the new owners must be informed of the pup’s genetic status.
It is recommended that all breeding animals have their PRA(PRCD) status determined before breeding in order to not produce PRA affected puppies.
4. Eyes – other conditions – not all inherited eye problems have a convenient DNA test. There are other eye conditions that do occur in both the Stumpy and the Cattle Dog and there is recent evidence that there may be another type of PRA that is not yet documented. Until this situation is further resolved we recommend that annual eye examinations are done on breeding stock.
It is recommended that all breeding stock be regularly checked by an ophthalmologist to determine their eye sight status.