Jack Russell Terriers
Jack Russell Terriers are sturdy and tough, measuring between 10" and 15" at the withers. The
body length must be in proportion to the height, and the dog should present a compact, balanced image. Predominantly white in coloration (more than 51%) with black and/or tan markings, they exhibit a smooth, broken or rough coat. The skin can sometimes show a pattern of small black or brown spots, referred to as "ticking", that do not carry through to the outer coat. All coat types should be dense double coats that are neither silky (in the case of smooth coats) or woolly (in the case of rough coats). The head should be of moderate width at the ears, narrowing to the eyes, and slightly flat between the ears. There should be a defined stop at the end of the muzzle where it meets the head but not overpronounced, with a black nose. The jaw should be powerful and well boned with a scissor bite and straight teeth. The eyes are almond shaped and dark colored, and should be full of life and intelligence. Small V-shaped ears of moderate thickness are carried forward on the head. When the dog is alert the tip of the V should not extend past the outer corner of the eyes. The tail is set high and docked to approximately five inches in order to provide a sufficient hand-hold for gripping the terrier. It is a serious fault for the dog to have its tail down when in the show ring. The Jack Russell should always appear balanced and alert.As the Jack Russell is primarily a working terrier, their most important physical characteristic is
their chest size, which must not be so large that it prevents the dog from entering and working in burrows. The red fox is the traditional quarry of the Jack Russell Terrier (JRT) so the working Jack Russell must be small enough to pursue its quarry. Red foxes vary in size, but across the world they average about 14 pounds in weight and have an average chest size of 12-14 inches at the widest part. As Barry Jones, the founding Chairman of the National Working Terrier Federation noted:The chest is, without doubt, the determining factor as to whether a terrier may follow its intended quarry underground. Too large and he/she is of little use for underground work, for no matter how determined the terrier may be, this physical setback will not be overcome in the nearly-tight situations it will encounter in working foxes. It may be thought t
he fox is a large animal - to the casual observer it would appear so. However, the bone structure of the fox is finer than that of a terrier, plus it has a loose-fitting, profuse pelt which lends itself to flexibility. I have not encountered a fox which could not be spanned at 14 inches circumference - this within a weight range of 10 lbs to 24 lbs, on average 300 foxes spanned a year.The chest of a Jack Russell should be easily spannable by the average size hands, meaning that if one wraps their hands around the dogs chest, directly behind their front legs, one should be able to put thumb to thumb, and forefinger to forefinger.
Temperament
Jack Russells are first and foremost a working terrier. Originally bred to bolt fox from their dens
during hunts, they are used on numerous ground-dwelling quarry such as groundhog, badger, and red and grey fox . The working JRT is required to locate quarry in the earth, and then either bolt or hold it in place until they are dug to. To accomplish this the dog must bark and work the quarry continuously. Because the preservation of this working ability is of highest importance to most registered breeders Jack Russells tend to be extremely intelligent, athletic, fearless, and vocal dogs. It is not uncommon for these dogs to become moody or destructive if they are not properly stimulated and exercised as they have a tendency to bore easily and will often create their own fun when left alone to entertain themselves.Their high energy and drive make these dogs ideally suited to a number of different dog sports such as flyball or agility. Obedience classes are also recommended to potential owners as Jack
Russells can be stubborn at times and aggressive towards other animals and humans if not properly socialized (a process that should continue throughout their whole lives). Despite their small size these dogs are not recommended for the condominium or apartment dweller unless the owner is ready to take on the daunting task of providing the dog with the necessary amount of exercise and stimulation. These are truly a big dog in a small package, and most suffer from a "Napoleon complex", which can sometimes lead to trouble involving larger animals. The JRT owner must be aware of these tendencies and be the cognizant party in many situations.Jack Russell terriers are not recommended for families with young children as they are intolerant of even unintentional abuse and will often return a perceived injustice with aggression. This is not to say that the Jack Russell can not cohabit with well behaved children but both dog
and child need to be properly introduced and educated on how to behave towards one another. JRTs are also extremely loyal towards their owners, and highly territorial. If a Jack Russell decides that something belongs to it even the most persuasive owner is unlikely to convince them otherwise.Despite some of these negative traits JRTs are exceptionally loving, intelligent dogs who have the ability to entertain their owners for hours with their comical antics. To understand the Jack Russell temperament, it must be remembered that they are first and foremost a "working dog." In other words, they were bred to aggressively run, chase, and flush out fox and badgers in the great hunts of England. These traits, so passionately guarded by Jack Russell breeders since the 19th century, have delivered to us a dog that is fearless, happy, alert, confident, intelligent and lively. A dog that is ready to meet the world on a moment's notice; this is the Jack Russell temperament in a nutshell.
Health
Jack Russell terriers are known for longevity and health due in a large part to a diverse gene pool. The JRTCA specifically regulates inbreeding and line breeding to a 16% coefficient unlike
many of the kennel club show dog breeds. A well-cared-for Jack Russell can live well into its teens, remaining active right into its senior years. The typical lifespan is between 11 and 18 years.Health concerns with the breed include hereditary cataracts, primary lens luxation, congenital deafness, medial patellar luxation, cerebellar ataxia, Legg-Calve-Perthes Disease, myasthenia gravis, atopy, general joint problems, and von Willebrand's disease. Responsible breeders have breeding stock BAER tested for hearing as juveniles and CERF (Canine Eye Registry Foundation) tested annually to check for any hereditary defects. Although not commonly a problem in this breed some breeders choose to have their dogs OFA inspected for potential joint problems.
History
The small white fox-working terriers we know today were first bred by the Reverend John Russell, a parson and hunting enthusiast born in 1795. In his last year of university at Oxford, he bought a small white and tan terrier female called Trump from the milk man. Trump was
purchased based upon appearance alone. (Burns, 2005) She was the basis for a breeding program to develop a terrier with high stamina for the hunt as well as the courage and formation to chase out foxes that had gone to ground. An important attribute in this dog was a tempered aggressiveness that would provide them with the necessary drive to pursue and bolt the fox without resulting in physical harm to the quarry, effectively ending the chase, which was considered unsporting. This line of terriers developed by John Russell was well respected for these qualities and his dogs were often taken on by hunt enthusiasts. It is unlikely, however, that any dogs alive today are descended from Trump, as Russell was forced to sell all of his dogs on more than one occasion because of financial difficulty, and had only four aged (and nonbreeding) terriers left when he died in 1883.The only painting that exists of Trump was painted more than 40 years after the dog died, and it was painted by someone who had never seen the original animal. Russell said the painting was "a good likeness", but he may have been more polite than honest in this. The painting was commissioned by Edward VII (then Prince of Wales) who befriended Russell in his old age, and had the painting done as an homage to the old man.
While it is often stated that Trump was "14 inches tall and weighed 14 pounds," there is no source for this statement, and it appears to have been penned by someone who had never met Russell and had only seen the painting of Trump (to which there is nothing to suggest scale).
While Trump's appearance is murky, and her size a complete mystery, the fox dens of Devon, England, where John Russell once hunted, are well known. Terrierman Eddie Chapman, who has hunted those same Devon earths for more than 30 years, notes that "I can state categorically that if given the choice, ninety-nine percent of hunt terrier men would buy an under 12" worker, if it was available, over a 14" one.". To this day most working terrier enthusiasts seem to prefer a dog around 12 inches tall.
The Reverend John Russell did not have Jack Russell terriers – he had white-bodied fox-working dogs that, in his day, were simply called “fox terriers.” Although Rev. Russell was asked to judge a number of fox terrier competitions he refrained from showing any of his own dogs and bred them with the hunt field in mind. He is quoted as saying "True terriers [my dogs] were, but differing from the present show dogs as the wild eglantine differs from a garden rose.". The term “Jack Russell Terrier” was coined after the Reverend John Russell was dead, and was used to differentiate small working terriers from larger nonworking Fox Terriers that, by 1900, dominated the Kennel Club show ring and bench.
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