Physical examination of cattle: parts I and II (Proceedings) - Veterinary Healthcare
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Physical examination of cattle: parts I and II (Proceedings)


CVC IN SAN DIEGO PROCEEDINGS


The exam up close

The next part of the physical examination is conducted with the animal restrained in a head chute. The order in which most of the examination is conducted is not important except that the rectal exam should be conducted at or near the end of the examination. The following description is the sequence that I usually follow. In dairy cattle particularly, it is often important to collect urine to check for ketonuria. This can most easily be accomplished without catheterization if it is done before the cow is "disturbed" by the physical examination. Stroke the vulva or perineum without touching any other part of the cow. Bulls will often urinate if their sheath is grasped at the orifice and "shaken" vigorously for 30 seconds. If the animal is lying in a stall and rises when the examiner approaches, it will frequently urinate and defecate spontaneously. Rectal temperature, pulse and respiration should always be measured. If the examiner stands on the left side of the animal while taking the temperature, rumen motility can be assessed simultaneously. After measuring and recording the temperature and assessing rumen motility, auscult the heart for rate, rhythm and murmurs. Remember that in order to auscult the heart, the head of the stethoscope must be pushed cranially behind the elbow and humerus. This is especially true in heavily muscled beef cattle. Next, listen to the lung fields and record the respiratory rate. Reference ranges for mature cattle are as follows: RR (12-36 bpm); HR (50-80 bpm); rectal temp (100.5-102.5F, 38-39C); Rumen contractions (2-3 in 2 minutes). For calves, these values are: RR (20-50 bpm); HR (90-112 bpm); rectal temp (101.4-103.4F, 38.5-39.5C) It is important to remember that lung sounds in cattle are usually quieter than they are in horses and small ruminants. Therefore, careful attention must be paid to detect abnormalities. The most frequent change in the lung sounds of cattle (except feedlot cattle perhaps) is simply an increase in the normal breath sounds which is caused by tachypnea. Heart failure, pulmonary disease, excitement, exertion, or elevated body temperature (which may be due to infection, exertion or high environmental temperature) may cause tachypnea. Except for pulmonary disease and pulmonary edema secondary to left heart failure, all of these other conditions will cause a simple elevation in respiratory rate and effort which is accompanied by louder-than-normal sounds, but which is not accompanied by crackles, wheezes, increased bronchial sounds or areas of dullness. In my experience the most frequent abnormal lung sound is increased large airway or bronchial sounds which are indicative of lung consolidation. It is a misconception that consolidated bovine lungs produce areas of dullness on auscultation. Often severe pneumonia in cattle is accompanied simply by increased large airway sounds but not crackles and wheezes. If areas of diminished or absent lung sounds are noted, one should suspect pleural effusion or lung abscess. It is critical to differentiate between true lung sounds and upper airway (nasal, laryngeal, pharyngeal and tracheal) sounds. Referred upper airway sounds can be heard loudly in the thorax, but if one listens over the trachea and pharyngeal area, the sounds are louder. Also, most sounds associated with breathing that are audible without a stethoscope are associated with the upper airway. Inspiratory sounds are almost always associated with a narrowing of the lumen of the upper airway. Audible grunts are occasionally heard, and these are consciously made sounds that usually reflect pain or severe disease that may not involve the respiratory tract. In young cattle, percussion of the thorax may help detect lung consolidation or pleural fluid, but this technique has been of limited value to me in older cattle, particularly beef cattle. After ausculting the thoracic cavity, move to the abdominal cavity and perform simultaneous auscultation and percussion (pinging) on both sides of the abdomen. Tests for abdominal pain can be conducted at this point. These include the withers pinch test and the xyphoid pressure test. The withers pinch test is performed by abruptly and firmly squeezing the animal rights dorsal midline over the withers. The interpretation of the test is as follows: the animal ventral flexes and grunts-positive for cranial abdominal pain; the animal ventral flexes and does not grunt-negative for cranial abdominal pain; animal neither ventral flexes or grunts or shows signs of discomfort- inconclusive results.


Table 1: Assessing hydration in calves (From Walker and Constable, JAVMA, 1998)
After completion of examination of the thoracic and abdominal cavities, one moves to the head of the animal. Hydration is best assessed by measuring eyeball recession and tenting of the skin of the neck. The values for assessing dehydration (Table 1) have been validated for calves by Constable, et al, but not for mature cattle. Anecdotally, I feel that the values for skin tent are probably similar in calves and cattle.

In suspected neurological cases, it is very important to do a thorough examination of the head, mouth and neck region. Begin by observing the animal from directly in front. One can observe the positions of the ears, eyelids, lips and eyeballs. After observing the animal's head, the examination of the head in neck begins by noting the temperature of the ears. Cold ears indicate hypocalcemia or shock. Look in the ears for otitis externa. The oral examination follows. One should always be mindful of rabies before examining the mouth of cattle, especially those suspected to have neurological disease, choke, or bloat. Gloves and protective clothing should be worn before examining the mouth of any animal with central nervous system disease. Look at the lips, gums, dental pad, hard palate and tongue for color, vesicles and ulcerations. Gingival mucous membrane color and capillary refill time are much more difficult to assess and interpret in cattle than in horses. Vulvar mucous membrane pallor is usually easier to detect (except in bulls & steers!). While examining the gums, check the incisors for eruption, color, wear and soundness. Grasp the tongue (a towel helps) and pull it to one side assessing consistency and muscle tone as you do. Look for ulceration, foreign body or ranulae on the underside of the tongue. Examine the cheek teeth for wear, points, attrition or overgrowth and the buccal mucosa for lacerations, ulceration or blunting of the papillae. "Impacted cud" may be in the cheek or under the tongue. Pull the tongue to the other side and repeat. Smell the breath and oral cavity for a necrotic odor, ammonia or ketones. Visual examination of the oropharynx can sometimes be accomplished with the use of a speculum (like a Drinkwater gag) and a flashlight. The torus lingua makes visualization of the pharynx difficult in some cases. Be ready to catch brief glimpses, especially when the animal bellows. Retropharyngeal masses, perforations, ulceration, and laryngeal lesions may be observed in this manner. Optimal visualization of the pharynx, larynx and esophagus is obtained by endoscopy. Traumatic pharyngitis (usually iatrogenic), necrotic laryngitis, chondritis, etc. can be visualized by nasal endoscopy. (Note: bovine nasal passages are smaller relative to body weight, than equine.) The esophagus can be examined for ulceration, laceration, choke, etc. Unlike the equine stomach, the ruminant forestomachs and abomasum cannot be examined by easily endoscopy. To examine the throat manually, insert the hand into the mouth while pushing the tongue between the cheek teeth nearest you. Do not keep your arm in the mouth for too long as the animal cannot breathe and may struggle and bite.


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Source: CVC IN SAN DIEGO PROCEEDINGS,
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