A Detailed Explanation of Visual Inspection Methods in Dog Disease Diagnosis Techniques
Examining and identifying certain abnormal manifestations in a sick dog is called diagnosis. Some abnormal manifestations in sick dogs are obvious and easy to detect and identify. However, some mild or inconspicuous manifestations are often difficult to distinguish from normal phenomena. This requires the use of special diagnostic methods or instruments for examination, followed by comprehensive analysis, to finally determine whether the dog is ill and what condition it has. Of course, some of these are carried out by veterinary professionals, while some examination and analysis items should also be known and mastered by dog owners. The simple diagnostic methods for dog diseases are introduced as follows:
(1) Visual inspection
The dog must be kept in a quiet state and observed with our eyes for any abnormal manifestations. Otherwise, the normal enhancement of bodily functions caused by strenuous activity may be misdiagnosed as abnormal. For example, after a dog has exercised strenuously or struggled during capture, its heart rate will certainly increase, making it difficult to distinguish whether it is normal or abnormal. At the same time, dog lovers must also know the various normal physiological characteristics of dogs in order to detect abnormal phenomena. Visual inspection should include examination of the following aspects:
1. Mental state
A healthy dog is lively and adorable, full of energy, agile in movement, with bright eyes, and both ears often turning with sounds. Even when sleeping, it always remains alert; upon hearing the slightest noise, it pricks up its ears and listens, with both eyes fixed on the direction of the sound, displaying a very alert mental state.
If a dog shows dull or half-closed eyes, is unwilling to move, prefers to lie still, has sluggish or no response of both ears to external stimuli, appears apathetic, or even comatose, these all belong to a state of neural inhibition, called depression or coma. Some sick dogs exhibit restlessness, running around indoors and outdoors, fearfulness, loud screaming, walking aimlessly, circling, or even biting various objects indiscriminately; such a mental state is called excitement or mania. Both of the above mental states are abnormal mental manifestations.
2. Nutritional status
To judge whether a dog's nutritional status is good or bad, mainly observe its body condition and coat. A healthy dog should be moderately fat and lean, with full and strong muscles, and a smooth, glossy coat that gives people a comfortable feeling. If a dog is emaciated, with flabby and weak muscles, a rough, dull, and dry coat, and tail hair standing on end, it often indicates parasitic diseases, skin diseases, chronic digestive tract diseases, or certain infectious diseases.
3. Posture
When a dog is standing or walking, if its limbs are stiff and it dares not bear weight, or if it shows weakness and lack of strength in its limbs when standing or moving, it indicates abnormalities in the limbs. If a dog lies with its body curled up, head tucked under the abdomen, or in an unnatural lying posture and frequently turning over, it indicates abdominal pain.
4. Body temperature
Under normal living conditions, a healthy dog's body temperature remains within a certain range, usually lowest in the early morning and slightly higher in the afternoon, with the temperature difference over a 24-hour period generally not exceeding 1°C. If it exceeds 1°C, or if the temperature is high in the morning and low in the afternoon, it indicates abnormal body temperature. The normal body temperature of a healthy dog is: 38.5-39°C for young dogs and 37.5-38.5°C for adult dogs. A simple method for judging fever in dogs is to analyze from the dog's nose, ear base, and mental state. A normal dog's nose tip is cool and moist, and the skin temperature at the ear base is the same as other parts. If the dog's nose tip (nasal mirror) is dry and hot, the skin temperature at the ear base is higher than other parts, and the dog is listless, has poor appetite but increased thirst, it indicates that the dog has an elevated body temperature. In most infectious diseases, inflammation of the respiratory tract, digestive tract, and other organs, sunstroke, and heatstroke, body temperature rises. In conditions such as poisoning, severe exhaustion, malnutrition, and anemia, body temperature often decreases.
The most accurate method for measuring body temperature is to use a thermometer. When measuring, the operator shakes the mercury column of the thermometer down below 35°C, wipes and disinfects it with an alcohol cotton ball, and applies a small amount of lubricant (liquid paraffin). The dog is properly restrained by an assistant, and the person measuring lifts the tail slightly and slowly inserts the thermometer into the anus. After insertion, prevent the thermometer from falling out, and it can be removed after about 3 minutes to read the degree. When a dog is excited, nervous, or after exercise, the rectal temperature may rise slightly.
5. Observation of the respiratory system
(1) Respiratory status: The dog must be observed in a quiet state. Examination of respiratory status should include respiratory rate, respiratory pattern, and whether breathing is difficult.
(2) Respiratory rate: Generally measured by the rising and falling movements of the chest and abdomen, that is, one rise and one fall of the chest and abdomen counts as 1 breath. In cold seasons, it can also be measured by the exhaled air flow. The respiratory rate of a healthy dog is 15-30 times per minute. The respiratory rate is often affected by certain physiological factors and external conditions. For example, young dogs have a slightly higher rate than adult dogs, pregnant dogs have a higher rate than non-pregnant females, and especially during exercise or excitement, it can increase many times. In addition, changes in temperature and season can also affect changes in respiratory rate.
(2) Respiratory pattern: The normal respiratory pattern of a dog is thoracic breathing. If during breathing the abdominal wall movement is more obvious than the chest wall movement (abdominal breathing), or the chest wall and abdominal wall move simultaneously (thoracoabdominal breathing), it indicates disease in the chest or abdomen, such as pleurisy, pleural effusion, or rib fracture.
(3) Respiratory rhythm: Examining a dog's respiratory rhythm is also very important for the diagnosis of respiratory system diseases. The normal breathing of a healthy dog consists of accurate and rhythmic alternating movements, that is, inspiration is immediately followed by expiration, and after each breath, there is a brief pause before the next breath, repeating in cycles very regularly, so it is called rhythmic breathing. Rhythm disorder is an abnormal phenomenon. However, the respiratory rhythm of a healthy dog can undergo temporary changes due to excitement, exercise, fear, screaming, sniffing, etc., and care should be taken to distinguish these from pathological changes. Pain, hypoxia, neural excitement, and substantial lung lesions can all cause pathological increases in frequency. In toxic coma, the frequency decreases. In encephalitis and toxemia, the frequency is sometimes fast and sometimes slow ("Cheyne-Stokes" breathing). When a sick dog shows open-mouth breathing, extension of the head and neck, displacement of the ribs forward and upward, and outward expansion of the elbows during respiration, it is dyspnea caused by respiratory tract obstruction. If a sick dog has shallow breathing and an increased respiratory rate, it indicates that the lungs cannot fully expand, commonly seen in rib fracture, pneumonia, pneumothorax, or pleurisy. When the respiratory tract is narrowed due to compression or obstruction by foreign bodies or tumors, symptoms of dyspnea can also appear.
(3) Nasal discharge: A healthy dog's nose almost does not discharge secretions. When a dog catches a cold or has respiratory tract inflammation, secretions often flow from the nostrils. The nature of the secretions includes serous (clear nasal mucus), mucous, and when there is purulent inflammation, the nasal discharge may be purulent (purulent nasal mucus), and may also be mixed with blood or fine bubbles. The amount of secretion often changes with the degree of inflammation. Sometimes nasal discharge is not seen, which may be because the dog has licked or wiped it off. But when the condition is severe, it no longer licks its nostrils.