Friday 7 March 2008

>>Withers

Withers

The location of the withers on a horse.
The location of the withers on a horse.

The withers is the highest point on the back of a non-upright animal, on the ridge between its shoulder blades.

Horses

They are made up by the dorsal spinal processes of the first 5 to 9 thoracic vertebrae (every horse has 18 thoracic vertebrae), which are unusually long in this area. The processes of the withers are less than 6" in height on the average horse. Since they do not move relative to the ground (as does the horse's head), the height of a horse is measured from the ground to the withers. Horse sizes are extremely variable, from small pony breeds to large draft breeds. The height of the withers on an average Thoroughbred is 16 hands (5' 4").

Conformational issues

The withers of the horse are considered in evaluating conformation. Generally, a horse should have well-defined withers, as they are considered an important attachment point for the muscles of the torso. Withers of medium height are preferred, as high withers make it difficult to fit a saddle and are often associated with a narrow chest, and low withers (known as "mutton withers") do not provide a ridge to help keep the saddle in place.

More importantly, the dorsal spinal processes provide an attachment for the muscles that support the shoulder. Horses do not have a clavicle, so the shoulder can freely rotate backwards. If the vertebrae of the withers are long (front to back), the shoulder is more free to move backwards. This allows for an increase of stride length (and so it can increase the horse's speed). It is also important in jumping, as the shoulder must rotate back for the horse to make his forearm more parallel to the ground, which will then raise the animal's knees upward and get the lower legs out of the way. Therefore, the withers have a direct impact on one of the most important points of conformation: the shoulder.

Dogs

In dogs, the height of the withers is often used to determine the dog's jump height in various dog sports. It is also often a determining factor in whether the dog conforms to the show-quality standards for its breed.

Medical problems

Inflammation of the bursa in this region is called fistulous withers by veterinary surgeons

>>Snout

Snout

A horse's snout.
A horse's snout.

A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. The snout is also often called a muzzle. A piece of equipment also called a muzzle can be placed over the snout to prevent the animal from biting or eating, often used before and after horse races (see animal muzzle).

A wet snout nose is called a rhinarium.

Dog's muzzle

Dogs' muzzles range in shape from extremely long and thin (dolichocephalic), as in the Rough Collie to nearly nonexistent because it is so flat (extreme brachycephalic), as in the Pug. Some breeds, such as many sled dogs and Spitz types, have muzzles that somewhat resemble the original wolf's in size and shape, and others in the less extreme range have shortened it somewhat (mesocephalic) as in many hounds.


This Black and Tan Coonhound's flews hang well below its lower jaw.
This Black and Tan Coonhound's flews hang well below its lower jaw.

The muzzle begins at the stop, just below the eyes, and contains the dog's nose and mouth. Most of the dog's upper muzzle contains organs for detecting scents. The loose flaps of skin on the sides of the upper muzzle that hang to different lengths over the dog's mouth are called flews. The snout is considered a weak point on most animals, because of its structure an animal can be easily stunned or even knocked out by applying sufficient force.

>>Stenotic nares

Stenotic nares

Before surgury
Before surgury
After surgury
After surgury

Stenotic nares is part of the brachycephalic syndrome of short-nosed dogs. Breeds such as Boxers, Bulldogs, Cavalier King Charles Spaniels, Pugs, Boston Terriers, Shih Tzus, Lasa Aphsas, etc. are all considered brachycephalic breeds. Stenotic nares means the nostrils are pinched or narrow. This makes it more difficult to breathe and causes snorting and snoring in these animals. It is a congenital trait; these animals are born with it. Veterinarians perform a simple surgery to help widen the nares, often at the same time as a spay or neuter.