How to Conduct Tentative Diagnosis in an Animal

[Kev]

Tentative diagnosis is a temporary diagnosis made by an animal health professional based on the preliminary evaluation of an animal's symptoms, medical history, and physical examination. It is important because it helps guide further diagnostic tests, monitoring, and treatments while waiting for confirmatory test results.

Tentative diagnosis is one that will lead you to identifying the specific problem with your animal. After carrying out the general diagnoses we have covered so far, you can complement them with the following techniques to isolate the case:

a) Palpation​

Involves direct feeling with the hands/fingers for the size of a swelling, consistency (whether soft or hard), and sensitivity (to pain and temperature).

b) Percussion​

Strike the body surface to set the deep parts into vibration. These vibrations will emit audible sound, which you can use to tell if the animal is sick or not.

c) Ballottement (tactile percussion)​

This technique combines both palpation and percussion. It is a useful technique for diagnosing pregnancy in small animals.

d) Auscultation​

Involves listening to sounds produced by the organs. You can listen directly by placing your ear above the surface or by use of a stethoscope.

e) Auscultation and percussion​

Set the organs in motion and listen to the sounds they produce.

Parameters used for tentative diagnosis​

i) Temperature​

The health of the animal affects its temperature. Temperature could be normal, high, or low. These deviations could be defines as follows:

1. Hypothermia– lower than the normal temperature
2. Hyperthermia– higher than the normal temperature
3. Pyrexia/fever– high temperature mixed with an infection
4. Septicaemia – hyperthermia with infectious organisms in the blood
5. Toxaemia– high temperature with infectious organisms producing toxins in the blood

ii) Pulse​

Determines the heartbeat rate of the animal. For large animals, you can detect this at the mid-coccidial artery (in the tail end). Use fumeral artery for small animals. You may notice the following from this examination:

Tachycardia - marked increase in pulse rate e.g. during septicaemia or toxaemia. It could also happen during circulatory failure, extreme pain or excitement.

Bradycardia – marked decrease in pulse rate, which occurs mainly on space-occupying lesions in the brain or diaphragm.

iii) Rectal palpation​

Useful for pregnancy diagnosis and deformities in organs.

iv) Abdominal auscultation​

You can listen to abdominal movements in animals with digestive problems.

Confirmatory Diagnosis (Laboratory Tests)​

Take samples for lab examination. Ensure you follow the good sampling practices.

The samples include:

1) Blood​

Use a dry sterile needle and syringe to collect the blood sample. If you are looking for large samples, use the jugular vein to draw the sample.

You can also use coccidial veins or the veins on the tip of the ears to draw samples.

Types of blood samples used for lab analysis

1. EDTA– contains an anti-coagulant to prevent clotting
2. Whole blood– encourages clotting and the blood separates into serum and solids. The serum is useful in identifying the type of infection.

2) Urine​

Use a clean and sterile universal bottle to collect the sample. You can use the urine for urinalysis, sugar content, and culture for microbiological analysis.

3) Faeces​

You can use the faeces for identifying worm infections and for cultural isolation to identify bacterial infections.

4) Lymph node​

Pick a prescapular or parotid lymph node biopsy in a clean dry bottle. You can use the sample for smears and bacterial isolation.

5) Skin scrapping​

Scape deep into the skin using a clean scalpel and collect in a clean container for ecto-parasite and fungal analysis.

6) Secretions​

Could be milk or pus. Collect in a clean sampling bottle for chemical or biological analysis.

7) Tissue sections​

Take a section of the organ to check for abnormalities like tumors.

8) Others​

You can also collect samples from the feeds, organs, chemicals, plants, content of the stomach, etc.