Jack Russell Terrier
The Jack Russell Terrier is not a breed recognised by the Kennel Club but they are a very popular small dog with pet owners. The Jack Russell is typically intelligent and tenacious, playful and fun-loving. They are quick to learn, good escape artists, and love to dig in the garden. Their love of digging comes from their origins as ratters who will catch and kill their prey. They are wonderful little character dogs and full of joy, but can be a bit barky and assertive. They moult a lot so would not suit an owner who is house proud or who likes a quiet life. He needs an owner who will play with him and give him plenty of exercise every day. Jack Russells are generally healthy and long lived, but are prone to obesity and owners should avoid over feeding.
Inbreeding Coefficient - COI
(Should be as low as possible)
The UK Kennel Club breed average COI is 6% - see 'A Beginners Guide to COI'
Effective Population Size - EPSTBC
EPS is a measure of how many individuals are contributing genetically to a breed population. It is a measure of the size of the gene pool in a breed. Lower than 100 is considered critical by conservationists and below 50 brings a breed close to extinction. For more information see the Kennel Club article.
Health and Welfare Problems due to Conformation
(Body shape and physical characteristics)
Eye disease: Primary lens luxation (PLL) (annual testing); Progressive retinal atrophy (PRA) (annual testing) (progressive loss of vision).
Estimated Breeding Values (EBVs) are now available for Hip Dysplasia and Elbow Dysplasia:
DNA Tests Available
- Primary lens luxation (PLL)
- Late Onset Ataxia (LOA) (progressive brain disease causing wobbliness)
Unofficial (Breed Club) Schemes
Ask the breeder to show you the certificates for the above tests/screening for both parents. If any of the above tests have not been considered necessary by the breeder (and there may be good reasons), ask her to explain why.
Other Diseases Reported
(For which there are currently no genetic or screening tests for sire or dam)
- Deafness (in some white JRs)
- Ataxia (progressive disease of the brain causing inco-ordination and falling over)
- Myaesthenia (muscle disease causing weakness)
- Legg-Calve-Perthes disease (diseased femoral head causing hind limb lameness)
- Patellar luxation (displaced kneecap)
- Von Willebrand’s disease (a blood clotting disorder)
- Portosystemic shunt (abnormality of the blood circulation system, resulting in blood by-passing the liver)
- Immunodeficiency syndrome (causing recurrent infections)
Note that all of these diseases are uncommon.
Ask the breeder about the medical history of the parents, grandparents and great grandparents. Consider carefully whether to purchase a puppy if some of these or other diseases are in the family line.
Ask about the breeder’s policy in cases of serious genetic diseases occurring to your puppy in later life. Good breeders will request to be informed of such events in order to improve future breeding decisions. Some breeders will also agree to contribute towards medical costs or refund purchase price.
You are strongly advised to buy from a breeder who uses (or is prepared to use) the RSPCA / BVA AWF Puppy Contract and Puppy Information Pack (PIP): www.puppycontract.org.uk
You are also advised to buy from a breeder who follows the Dog Breeding Reform Group’s (DBRG) Standard for Dog Breeding: