Common Diseases of Farm Animals | Page 5

the condition of the heart and
blood-vessels. The frequency of the pulse beat varies in the different
species of animals. The smaller the animal the more frequent the pulse.
In young animals the number of beats per minute is greater than in
adults. Excitement or fear, especially if the animal possesses a nervous
temperament, increases the frequency of the pulse. During, and for a
short time after, feeding and exercise, the pulse rate is higher than when
the animal is standing at rest.
The following table gives the normal rate of the pulse beats per minute:
Horse 36 to 40 per minute Ox 45 to 50 per minute Sheep 70 to 80 per
minute Pig 70 to 80 per minute Dog 90 to 100 per minute
In sickness the pulse is instantly responsive. It is of the greatest aid in
diagnosing and in noting the progress of the disease. The following
varieties of pulse may be mentioned: _frequent, infrequent, quick, slow,
large, small, hard, soft_ and intermittent. The terms frequent and
infrequent refer to the number of pulse beats in a given time; quick and
slow to the length of time required for the pulse wave to pass beneath
the finger; large and small to the volume of the wave; hard and soft to
its compressibility; and intermittent to the occasional missing of a beat.
A pulse beat that is small and quick, or large and soft, is frequently met
with in diseases of a serious character.
[Illustration: FIG. 3.--The X on the lower border of the jaw indicates
the place where the pulse is taken.]
_The horse's pulse_ is taken from the submaxillary artery at a point
anterior to, or below the angle of the jaw and along its inferior border
(Fig. 3). It is here that the artery winds around the inferior border of the
jaw in an upward direction, and, because of its location immediately
beneath the skin, it can be readily located by pressing lightly over the
region with the fingers.

_Cattle's pulse_ is taken from the same artery as in the horse. The
artery is most superficial a little above the border of the jaw. It is more
difficult to find the pulse wave in cattle than it is in horses, because of
the larger amount of connective tissue just beneath the skin and the
heavier muscles of the jaw. A very satisfactory pulse may be found in
the small arteries located along the inferior part of the lateral region of
the tail and near its base.
_The sheep's pulse_ may be taken directly from the femoral artery by
placing the fingers over the inner region of the thigh. By pressing with
the hand over the region of the heart we may determine its condition.
_The hog's pulse_ can easily be taken from the femoral artery on the
internal region of the thigh. The artery crosses this region obliquely and
is quite superficial toward its anterior and lower portion.
_The dog's_ pulse is usually taken from the brachial artery. The pulse
wave can be readily felt by resting the fingers over the inner region of
the arm and just above the elbow. The character of the heart beats in
dogs may be determined by resting the hand on the chest wall.
RESPIRATION.--The frequency of the respirations varies with the
species. The following table gives the frequency of the respirations in
domestic animals:
Horse 8 to 10 per minute Ox 12 to 15 per minute Sheep 12 to 20 per
minute Dog 15 to 20 per minute Pig 10 to 15 per minute
The ratio of the heart beats to the respirations is about 1:4 or 1:5. This
ratio is not constant in ruminants. Rumination, muscular exertion and
excitement increase the frequency and cause the respirations to become
irregular. In disease the ratio between the heart beats and respirations is
greatly disturbed, and the character of the respiratory sounds and
movements may be greatly changed (Fig. 4).
[Illustration: FIG. 4.--Auscultation of the lungs can be practised to an
advantage over the outlined portion of the chest wall, only.]

Severe exercise and diseased conditions of the lungs cause the animal
to breathe rapidly and bring into use all of the respiratory muscles.
Such forced or labored breathing is a common symptom in serious lung
diseases, "bloat" in cattle, or any condition that may cause dyspnoea.
Horses affected with "heaves" show a double contraction of the
muscles in the region of the flank during expiration. In spasm of the
diaphragm or "thumps" the expiration appears to be a short, jerking
movement of the flank. In the abdominal form of respiration the
movements of the walls of the chest are limited. This occurs in pleurisy.
In the thoracic form of respiration the abdominal wall is held rigid and
the movement of