by Dr. Melanie Rettler, D.V.M - February 2006 In animal physiology, the term ”vital signs” refers to the temperature, pulse and respiration rates of the body (TPRs). While there are other important functions in the body, these three are fundamental to the maintenance of life. Diseases may be defined as “any abnormal structural or functional change in tissues of the body.” Though there are many direct and indirect causes of disease—such as wound or injury (trauma), parasites, congenital (present at birth), viruses and others—they all affect to some degree the vital signs of the body. It is important that animal owners try to understand what is “normal” in their own animals, try to see “changes” in the condition and appearance of their animals, and learn how an abnormal situation may be reflected in those vital signs. Usually, the first indications of disease are so slight as to go unnoticed by most people. The observant owner who can detect early symptoms and initiate proper action can play an important role in disease control. Early Warnings Appetite and attitude are two good yardsticks. If your animal is not interested in eating, or seems nervous, worried or depressed, you may want to check further. Knowing the three vital signs, what they might mean, and how to describe any variations to your veterinarian are discussed here. TEMPERATURE Temperature—“the degree of heat of a living body”—is actually the result of the balance between heat produced by basal metabolism, muscular activity of the body and heat lost from the body. Approximately 85% of heat loss is through the skin, the rest via lungs and digestive or urinary secretions. (Actual regulation of body temperature is accomplishes mainly through centers located in the brain.) An animal’s abnormal temperature (fever or hypothermia) may play a part in the veterinarian’s final diagnosis of a disease. This, then, is one of the first clues an observant owner can report: Fever - above normal limits Hypothermia - below normal limits Domestic animals do not have constant normal temperatures. Variations occur, in general, depending on physical activity, stage of pregnancy, time of day and environment. To take an animal’s temperature: Use a veterinary-type thermometer. Shake the mercury column in the bulb to end. Lubricate or moisten the tube. Insert the bulb end through the anus into the rectum. Insert the full length of the tube. (Veterinary thermometers have a glass loop at the end opposite the bulb. It is a wise practice to thread a length of string through the loop, then secure the string to tail hairs with a paper clip. Muscular contractions could draw in a thermometer.) Leave the thermometer in the rectum for about 3 minutes. Since some animals may object to the insertion of the thermometer, appropriate restraint should be considered. Normal Temperatures Horse 99.5—101.3°F Foal 99.5—102.2°F Cattle 100.4—103.1°F Sheep/Goats 102.2—104.9°F Swine 100.4—104.0°F When the body temperature increases at least by 1°F over the normal upper limit, the animal is considered have a fever. In most fevers, the temperature rises rapidly, reaches a peak, then falls to a lower level. (Generally, the height of the temperature indicates the height of the fever.) Four degrees of fever are listed: | Degree of Fever | Horse | Cow |
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| Mild Fever | 101.3—103.0°F | 103.1—104.6°F | | Moderate Fever | 103.0—104.8°F | 104.6—105.8°F | | High Fever | 104.8—106.0°F | 105.8—107.0°F | | Very High Fever | 106.0—110.0°F | 107.0—110.0°F |
If a fever is suspected, take the animal’s temperature at regular intervals in order to classify the fever. (Usually even in severe infectious diseases, the temperature never exceeds 106.0°F in horses, or 107.0°F in cows. However, in all animals suffering from heat stroke it may exceed 110.0°F.)
A word of caution—while measurement of temperature is one of the most reliable methods to judge degree of fever, it does not always have a direct relationship in animals, especially cattle. In cattle, an increase does not always represent the degree of fever. It is necessary to consider other symptoms such as chill, uneven distribution of external temperature (hot feet or ears), pulse and respiration rates, appetite, digestion and attitude, for example.
Subnormal temperature (hypothermia) may or may not indicate disease. It is seen in a variety of ailments (chemical poisoning, indigestion, calving paralysis) but is much less frequent than fever temperatures. PULSE Pulse is the “rhythmic, periodic thrust felt over an artery in time with the heartbeat.” Important facts to consider when taking the pulse are: Frequency - count the heartbeats occurring in one full minute for an accurate reading. Rhythm - a series of rhythmic beats following each other at regular intervals (normal pulse). Quality - the tension (or power you feel) on the arterial wall indicating volume of blood flow. Pulse can be felt with the fingers (palpated) in arteries close to the skin surface, where they are in soft tissue and can be pressed against a hard or bony structure. When the artery is located, it should be held steady with the fingers and gentle pressure applied. Try to determine rate first, then go back for another full minute to judge rhythm and quality. Horses The pulse is taken where a large artery (the external maxillary artery) crosses the underside edge of the lower jaw bone. It may also be taken on the inside of the forearm (radius bone) where the radial artery travels down that bone. Cattle The pulse may be taken (external maxillary artery) at the point where this artery passes around the lower edge of the jawbone, just in front of the chewing muscle (masseter). This is approximately the same location as on the horse. When fingers are placed flat on the cheek in front of the masseter muscle, then moved back and forth, the artery is easily felt. Sheep and goats One of two major arteries that run down the inside of the hind leg (the saphenous artery) is the most easily located. Swine Pulse cannot be felt at all. With this animal, the heart itself must be palpated directly. Terms used to define pulse frequency are: Frequent - quick, rapid Infrequent - slow Normal pulse frequency will vary in different species and in individual animals. Age, size, sex, breed, atmospheric conditions, time of day, exercise, eating and excitement are factors which produce variations. Average (normal) | Animal | | Heartbeats per minute |
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| Horses | adult | 28—40 | | Foal | (newborn) | 100 | | Foal | (6-12 mos.) | 45—60 | | Cattle | | 40—70 | | Sheep/Goats | | 60—90 | | Swine | | 60—100 |
RESPIRATION Respiration is the act of breathing. Specifically, it is the taking in of oxygen, its usage in body tissues, and the giving off of carbon dioxide. Respiration occurs in 2 parts: Inspiration - breathing “in” Expiration - breathing “out” These two actions take air into the lungs, and push it out again.
The respiration system frequently is subjected to primary and secondary disease. Thus, it is important that livestock owners give full consideration to the “area affected” when an animal is considered “not normal” in this regard. A long list of serious diseases that affect all farm animals eventually spread and settle in areas of the respiratory system. Observations To check the functions of the respiratory system of your animal, begin at the nostrils and work rearward. Listen and look for abnormalities in: Breathing - Noisy strained or panting Breath - unpleasant or foul odor Nasal discharge (check nostrils as well) Lumps or swelling in the jaw areas Coughing or wheezing Surface and sounds of the throat and chest To observe respiration in your animal consider: Rate – number of inspirations per minute Depth – the intensity (or straining) Character – normal breathing shows and expansion and relaxation of the ribs and abdomen. (If either of these actions shows more or less effort, the character of the breathing is said to be affected.) Rhythm – change in “in-out” pattern, such as panting or gasping Sounds – normal breathing is almost soundless, unless the animal is at work or exercising. Snuffling, sneezing, wheezing, rattling or groaning indicates an abnormal situation. Since changes in breathing rate are due to many factors, (including body size, age, exercising or excitement, pregnancy, full digestive tract, or atmospheric and environmental temperatures), it is a wise idea to check the rate of two or three animals in order to compare results. Check the movement and sound at the nostril and in the chest areas to count respiration:
Normal range (mature animal at rest)
| Animal | Respiration counts |
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| Horse | 8—16 per minute | | Beef Cow | 10—30 per minute | | Dairy Cow | 18—28 per minute | | Sheep/Goats | 12—20 per minute | | Pig | 8—18 per minute |
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