meet the... Jack Russell Terrier

Head

• General Appearance: Mesaticephalic skull-type, moderate in size, wedge-shaped, and in proportion to the rest of the body. The topskull (from stop to occiput) is of medium length and moderate width, being almost as wide as the topskull is long. From the front, the topskull appears flat between the ears. The topskull will appear flat or slightly curved from the side. The skull tapers to a wide muzzle formed by strong jaws. The head is clean-cut and without excess skin or wrinkles. It should appear neither long, like that of the Fox Terrier, nor short, like that of the Border Terrier.
• Expression: Keen, alert, confident, somewhat mischievous, and capable.
• Stop: The stop may range from shallow (more common in Parson Russell Terrier) to well-defined, so long as the dog represents the overall correct type. The stop should never be overly pronounced.
• Skull: The ideal muzzle-to-skull ratio is between 1:1 and 3:2, with the topskull being equal to, or just longer than, the muzzle.
  The ideal muzzle-to-skull axis may be parallel or may be convergent.
• Muzzle: The muzzle is full and broad. The upper and lower jaws have good bone substance, appearing strong and well-developed, never appearing snipy or weak. The lower jaw and upper jaw are equal in length.
• Lips or Flews: The lips are clean and fit tightly over the teeth and jaws.
• Nose: The nose is well-pigmented and black. The nostrils are well-opened.
• Cheeks: The cheeks are well-developed but not overly prominent.
• Dentition and Bite: Forty-two strong, clean, and white teeth. The bite may be level, scissor, or reverse-scissor. Contact must be made between the top and bottom incisors. Missing or broken teeth due to routine work are not to be penalized.
• Eyes: Moderate in size, oval to almond in shape, and medium to dark brown in color. The eye rims are well-fitted and well-pigmented. The eyes are never bulging. There should be sufficient bone in the surrounding orbital sockets to protect the eyes.
• Ears: Medium in size, set high on the skull and fairly far apart. They may be small to medium in size, V-shaped, and buttoned, dropped, or rose, so long as they are carried close to the head. When alerted, the tips of the ears should remain level with or above the corners of the eyes. The fold of the ear should be level with the topskull or just slightly above the level of the topskull. The ears are never long, hound-like, fully erect, or overly large.

Body and Tail

• General Description: Compact, solid, well-muscled, and good of substance. The body is never racy or refined. The width at the forequarters is approximately equal to the width at the hindquarters.
• Neck: Moderate length to allow for proud head carriage and powerfully muscled with a good arch. The neck tapers smoothly from the deeper and broader body toward the head. The neck is clean-cut and without excess skin, throatiness, or dewlap.
• Chest: Deep, not too broad, and never wider than deep. The brisket extends to the point of the elbows.
• Topline: Level from withers to croup. The back is broad, strongly muscled, and straight, yet supple. The loin is taut, flat, level, or slightly arched yet supportive. The back is never swayed or roached.
• Croup: May be flat and level with the back or gently sloped.
• Underline: A slight tuck-up is present. The underline is taut and firm, without any indication of sagging or excess weight.
• Ribs: Long, well-sprung, well-laid-back, and oval-shaped, never barrel-chested or slab-sided.
• Tail: Set high on the croup, thick at the base and tapering toward the tip. Carried in accordance with the dog’s mood and energy level, but never tucked. It is usually carried high when alerted or moving. It may drop to a neutral position when at rest. The tail may be left natural (preferred) or docked short. Natural tails are of a medium length, with the tip of the last vertebrae extending to the hock joints when held down. Natural tails may be straight or gently curved. Docked tails should be cut long, with the tip equal in height to the top of the dog’s ears.

Forequarters and Hindquarters

• Forequarters: The forequarters are always balanced with the hindquarters and well-angulated with well-laid-back shoulder blades. Shoulder blades are approximately equal in length to the upper arm and forearm.
• Elbows: The elbows are close to the body. The point of the elbows is approximately half the dog’s height at the withers.
• Forelegs: Frontal View: Straight, of good muscle, of moderate bone, and parallel to one another.
  Side View: The forelimbs appear straight with strong pasterns.
• Pasterns: Never weak or broken.
• Hindquarters: The upper and lower thighs are equal in length, strong, sturdy, of moderate bone, and well-muscled.
  Rear View: When viewed from the rear, the rear pasterns are parallel to one another.
  Side View: Good angulation will allow the rear toes to align with the point of the rump or within one to two paw-lengths behind the point of the rump, with the rear pasterns remaining perpendicular to the ground and parallel to one another.
• Stifle Joint: Well-angulated, with a good bend to well-let-down rear pasterns.
• Stifle Joint: The angulation of the hindquarters is always in balance with the angulation of the forequarters.
• Feet: Oval to round, compact, with well-arched toes and tough pads.

Coat

• Skin: Well-fitted, yet supple. The skin should never obstruct the outline of the dog.
• Coat Type: The Jack Russell Terrier comes in three coat varieties: the smooth coat, the rough coat, and the broken coat. All coat types, regardless of variety, should have a strong, weather-proof outer coat and a dense protective undercoat. All coats must be left naturally and free from excess trimming or clipping.
  
  Smooth coat variety: The coat is short, smooth, and close to the body throughout, with a thick undercoat. Slightly longer on the neck, forming a light ruff, and on the tail. No fringe or feather is permissible.
  
  Rough-coat variety: The coat is harsh, dense, and wiry. It is never soft or silky. The coat on the face may have wiry eyebrows, a beard, and mustache furnishings.
  
  Broken-coat variety: The coat length is intermediate in length and texture between the rough and the smooth. The body coat may be somewhat smooth, with a harsher texture, and the head may have rough furnishings. A slight ridge of rough hair may be present on the back.
• Coat Color or Pattern: White, or predominantly white, with the following markings: black, black with tan points, black saddle with tan, or black with creeping tan. Tan markings can range from biscuit, lemon, or light tan to chestnut or grizzle (not brindle), all with or without ticking.

Movement

The Jack Russell Terrier’s movement must be energetic, tireless, effortless, and efficient. The characteristics of a healthy structure are evident. When moving away, the forelegs and rear pasterns should remain parallel to one another. When viewing movement from the front, the forelegs should remain parallel, with elbows and paws moving neither in nor out. From the rear, the back pads should be visible when the rear legs are extended. As speed increases, the forelimbs and hindlimbs will converge to the centerline of gravity. From the side, the topline should remain firm and level. Good reach of movement in the front allows the forepaw to extend out in line with the nose. When extended, the width between the forefeet should be approximately equal to the width between the hindfeet when extended, indicating balance, good reach, and good drive. Dogs that exhibit any sign of breathing or locomotive difficulty shall be disqualified from the show ring.

Temperament

The Jack Russell Terrier is well-known for their bold, lively, active, curious, engaging, and intelligent nature. A true terrier and sportsman's hunting and digging instincts are strong and require training to curb or enhance them since the Jack Russell Terrier can become quite single-minded. Mature females tend to take life a bit more seriously, while males generally remain more playful. Any unprovoked aggressive or fearful behavior toward people is incorrect for this breed.

Faults

All dogs should be in proper healthy condition and free from disease or defect. Any departure from this description is considered a fault. Unless altered, all male dogs should have two fully descended testicles.