Clinical Diagnosis of Ruminant
Animals Diseases
Part I
‫التشخيص االكلينيكي ألمراض المجترات‬
‫الجزء األول‬
By
Prof. Dr. Ibrahim H.A. Abd El-Rahim
Professor of Infectious Diseases,
Animal Medicine Department,
Faculty of Veterinary Medicine, Assiut University
E-mail: vetrahim@hotmail.com
Introduction
‫المقدمة‬
Disease may be defined as “any abnormal structural and/or functional
change in the tissues of the body.
 Diseases caused by non-infectious agents (nutritional deficiency,
metabolic disorders and others) are non-infectious diseases
(general medicine)
‫الطب العام أو األمراض الباطنة‬
 Diseases caused by infectious agents (e.g. parasites, viruses,
bacteria, fungi, prion and others) are infectious diseases (specific
medicine)
‫الطب الخاص أو األمراض المعديه‬
 Pathogenic agent + susceptible animal + growth and multiplication of
the pathogen, and production of toxins + absorption + clinical signs =
infectious disease
‫المرض المعدى‬
 Infectious disease + transmission from one individual to another
by direct and/or indirect contact = contagious disease (Latin,
contagium = contact). ‫المرض الوبائي‬
 All contagious diseases are infectious diseases, but not all infectious
diseases are contagious diseases. ‫كل االمراض الوبائيه أمراض معدية وليس العكس‬
 Infectious disease + transmission between animals and man =
zoonotic disease
‫المرض المشترك‬
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Clinical examination of ruminant animals
‫الفحص االكلينيكي للحيوانات المجتره‬
Firstly: The veterinarians must take the utmost care during clinical
examination of animals, by attention to precautions and by giving clear
instructions, that neither the patient nor the helpers are placed at risk.
Secondly: On the other hand, obligation lies on the owner of the animal
to inform the veterinarian of any vices (such as kicking, sideways
pressing, biting) of the animal.
Instruments and requirements of clinical examinations
‫أدوات ومستلزمات الفحص االكلينيكي‬
In addition to protective clothing (veterinary smock or clinical coat,
washable apron, long gloves of rubber or plastic) the following
instruments are required:
-
Stethoscope
Clinical thermometer,
Heavy and light percussion hammers,
Plexer and plexemeter,
Torch,
Urethral catheter,
Vaginal speculum,
Milk stripping cup,
Restraining equipment (metal wedge gag, wooden mouth gag).
Stomach tube and probing.
Containers for collecting samples (tubes, bottles, or plastic bags).
I. Identification of cattle
‫تعريف الحيوان‬
The following are the principal criteria for the description of cattle:
breed, sex, age, body weight, ear mark, neck band number, colouration,
muzzle print, blood group formula, brand mark (or tattooing).
 Breed
‫السالله‬
Some breeds are predisposed to certain diseases. All foreign breeds are
highly susceptible for tropical infectious diseases.
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 Utilization
‫االستعمال‬
 Fattening animal tend to develop disorders associated with
intensive feeding (digestive disorders, laminitis).
 Dairy cows tend to develop metabolic disorders.
 Pregnant sheep tend to develop metabolic disorders (pregnancy
toxaemia)
 Sex and age
‫الجنس والعمر‬
 Young animals are more likely to become ill as a result of
parasitic invasion than the immune adults.
 Tuberculosis and paratuberculosis are chronic diseases of adults,
and so on.
 Body weight
‫الوزن‬
- Assessing the state of development and nutrition.
- It enables precise drug dosage to be calculated.
- Change in body weight is of some prognostic importance.
 Colour pattern
‫اللون‬
- In the case of black-and-white or red-and-white breeds, the photosensitization only affects the un-pigmented areas of skin.
 Ear tags and neck bands ‫رقم األذن أو رباط الرقبة‬
- Ear tags are used to identify cattle breeds of one colour.
- On free-running cattle, broad plastic neck bands with a number
printed on both sides are preferable.
 Branding and tattooing
‫الوشم‬
 Muzzle impression
‫بصمة الشفه العليا‬
 Blood group determination
‫فصيلة الدم‬
II. Case history
‫التاريخ المرضى‬
It is usually easy to obtain information on the location of the disease,
such as:
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 Absence of rumination, alternate bloat, colic or diarrhoea
(probable location of the disease in the digestive system);
 Nasal discharge, coughing or difficulty in breathing (probable
location in the respiratory system);
 Repeated posturing for urination, or passage of blood-tinged
urine (probable location in the urinary tract);
 Lameness or paralysis (location in locomotory or nervous
systems); etc.
Questions of particular importance are:
‫أسئلة ذات أهمية‬
 Duration of illness:
‫مدة المرض‬
 Peracute (lasting for between a few hours and two days), ‫فوق الحاد‬
 Acute (3 to 14 days),
‫حاد‬
 Subacute (2 to 4 weeks) or
‫تحت الحاد‬
 Chronic (over 4 weeks).
‫مزمن‬
 Nature, development and circumstances surrounding the symptoms:
 Wound + muscular spasm = tetanus;
 Dog bite + excitement = rabies;
 Recent calving + inability to stand = hypocalcaemic paresis.
 Probable cause of the condition:
‫السبب المحتمل‬
 Feeding, husbandry and utilization of the animal.
 Contact with other animals, has been purchased recently, and
from where.
 Treatment that has been instituted so far. ‫العالج السابق‬
Improvement or no improvement after previous treatment will provide
a guide to diagnosis and prognosis.
Common errors in attempted treatment are:
‫أخطاء شائعة عند العالج‬
 Forceful administration may resulting in inhalation pneumonia,
 Peritonitis after faulty trocarization of the rumen,
 Aggravation of lameness by incorrect claw trimming,
 Damage to the birth canal by forceful extraction of calf.
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III. General examination
‫الفحص العام‬
Features included in a general examination are:







Posture,
‫وضع الوقوف والجلوس‬
Behaviour,
‫السلوك‬
Nutritional state,
‫التغذية‬
Physical condition,
‫حالة الجسم‬
Body temperature.
‫درجة حرارة الجسم‬
Breathing rate,
‫معدل التنفس‬
Pulse rate and
‫النبض‬
 Posture
‫وضع الوقوف والجلوس‬
 Arched back and tense abdomen important signs of peritonitis,
particularly that resulting from traumatic reticulitis.
 Holding the fore legs wide apart postural anomaly characteristic
of diseases of pericardium and lungs.
 Animals with head and neck stretched out and held low perhaps
with the tongue extruded (oesophagus obstruction, dyspnea).
 A lying animal curled up with the head turned towards the chest
is symptomatic of comatose states, particularly parturient paresis.
 While an animal lying flat on its side with extended limbs and
head stretched backwards may have hypomagnesaemic tetany.
 Behaviour
‫السلوك‬
 Increased sensomotor stimulation (excitability): Restlessness,
throwing straw with the horns, pressing the head against objects.
 Decreased sensomotor stimulation (depression, paralysis, paresis):
In parturient paresis, the cow is lying down (unable to rise).
 Coma (unconsciousness) due to general intoxication.
 In acute lead poisoning. - Blindness, salivation, teeth grinding,
pressing forwards.
 Behaviour in botulism. – Recumbency with paralysis of all
muscles and tongue hanging out.
 In pseudorabies, restlessness and severe itching.
 After a few days of severe illness, cattle become dull, apathetic
and depressed.
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 Nutritional state
‫التغذية‬
When a patient is in a poor state of nutrition, it is necessary to find out
if this is due to primary or secondary under-nutrition.
 Emaciation (secondary inanition) results from illness which
affects the appetite of the animal (as in febrile systemic infections),
or its inability to ingest feed (actinobacillosis of the tongue).
 Wasting diseases such as gastrointestinal helminths, tuberculosis
and paratuberculosis) and they are usually chronic.
 Diseases with continuous diarrhoea can lead to rapid emaciation.
 Physical condition
‫حالة الجسم‬
This comprises the general external appearance of the patient from the
clinical aspect.
 By abnormalities in bodily condition an animal may be judged to
be mildly, moderately or severely ill.
 It is also possible to distinguish acutely or chronically ill cattle.
 The bodily condition of an animal with severe, chronic illness is
characterized by severe emaciation, stiffness and apathetic
appearance.
 Body temperature ‫درجة حرارة الجسم‬
The procedure for taking an animal’s temperature is:
(a) Shake the mercury column into the bulb end of the thermometer;
(b) Moisten or lubricate the tube by the application of water, soap or
mucus;
(c) Insert the bulb (the full length of the tube) into the rectum where
it can be held in position by means of a clothes peg attached to one
of the caudal folds; and
(d) Leave the thermometer in the rectum for about 2-3 minutes.
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Table 1. Normal body temperature in different animal species
ANIMAL SPECIES
Calves
Young cattle
Adult cattle
Sheep and goats
camels
Horse
Dogs and cats
NORMAL BODY TEMPERATURE
38.5 to 39.5°C
38.0 to 39.5 °C
38.0 to 39.0 °C
38.5 to 39.5°C
36 to 37
37.5 to 38.5
38 to 39
In general, animal temperatures will vary, depending on the following
factors: Age, time of day, environmental conditions, physical activity
(work), and reproductive function.
Fever
‫الحمى‬
Fever is a pathological state of increased heat production (increase in
the intensity of metabolism) and decreased heat loss. It is an important
curative and defensive process.
Fever is usually accompanied by:
-
Water retention,
Digestive disorders,
Increased breathing rate and heart rate
The skin surface temperature is mostly increased,
Dryness of mucous membranes,
In cattle, the muzzle is dry,
The eyes shine “feverishly” and
Sometimes, the animal shivers.
Degree of fever:
Table 2. Degree of fever in cattle
DEGREE OF FEVER
Mild fever
Moderate fever
High fever
CATTLE
39 .5 to 40°C
40 to 41°C
41 to 42°C
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Hypothermia
Pathological lowering of the body temperature in cattle to below 37.5 °C
is called hypothermia.
The course of fever:
 Biphasic fever: Viral infections are sometimes accompanied by a
biphasic temperature curve, in which the first peak is due to
viraemia, and the second to bacterial secondary infection.
 Saw-shaped fever curve: Temperature wit striking daily
variations (Peritonitis).
 Persistent fever: (in severe, acute bronchopneumonia, malignant
catarrhal fever, and certain forms of mastitis (E. coli infection).
 Continuous
 Remittent
 Intermittent
 Recurrent
 Atypical
 Breathing (respiratory) rate
‫معدل التنفس‬
Breathing rate is the number of the respiratory movements per minute,
by watching movements of the costal arch and flank.
Table 3. Normal respiratory rates in different animal species
ANIMAL SPECIES
NORMAL BREATHING
(RESPIRATORY) RATE
15-35
20-50
12 to 20
Adult cattle
Young calves
Sheep and Goats
In examining respiration in an animal, give attention to the following
factors:
 Rate –number of inspirations per minute.
 Depth – the intensity or indication of straining.
 Character – normal breathing involves an observable expansion
and relaxation of the ribs (costa) and abdominal wall.
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 Rhythm – change in duration of inspiration and expiration.
 Sound – normal breathing is noiseless except when the animal is
exercising or at work. Snuffling, sneezing, wheezing, rattling, or
groaning may indicate something abnormal.
Pathological conditions
- Polypnea means a pathological increase in breathing rate.
- Oligopnea means a decrease in breathing rate.
- Dyspnea – labored or difficult breathing.
 Pulse rate
‫النبض‬
Pulse rate is the number of pulse beats per minute. This is detected by
palpation of a suitable peripheral artery, such as:
- In cattle: External maxillary artery, directly after its passage
around the mandible, laterally at the anterior edge of the
masseter muscle. Coccygeal artery, I or 2 handbreadths from the
base of the tail can be also easily palpated.
- In sheep and goats, the saphenous artery, which runs down the
inside of the hind leg, is the most accessible location.
- In horses, pulse may also be taken on the inside of the forearm
(radial bone) where the radial artery travels down the bone.
The important factors to note in taking the pulse are:
(1) Frequency: Counting the number of heartbeats occurring in 1
min. Tachycardia is an increase in pulse rate while bradycardia
is a decrease.
(2) Rhythm: Pulse rhythm is normally regular, which means that the
intervals between individual pulse waves are of equal duration.
Irregularity is accompanied by unevenness of the pulse beat.
(3) Quality: Quality is best described as the tension on the arterial
wall; it is an indication of the volume of blood flow.
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Table 4. Normal pulse rates in different animal species
ANIMAL SPECIES
Unweaned calves
Young cattle
Barren &newly-calved cows
Heavily pregnant cows
Large bulls & oxen
Sheep and goats
 Summary of findings
NORMAL PULSE RATE
90 to 110
70 to 90
65 to 80
70 to 90
60 to 70
60 to 90
‫ملخص الفحص العام‬
When the general examination has been completed, a short summary of
the findings should be made, together with facts derived from the
history, in the following form:
1. The general health of the animal is not, slightly, moderately, or
severely disturbed.
2. The location of disease is probably in skin and sc tissue,
lymphatic system, circulatory system, respiratory system,
digestive system, urogenital system, locomotor apparatus, CNS.
 The special examination.
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‫الفحص الخاص‬
VI. Special examination
Special examination is to examine individual body systems more
thoroughly for diagnosis and differential diagnosis:









Hair, skin, SC tissue and visible mucous membranes ‫الجلد‬
Lymphatic system
‫الجهاز الليمفاوى‬
Circulation
‫الجهاز الدورى‬
Respiratory system
‫الجهاز التنفسى‬
Digestive system
‫الجهاز الهضمى‬
Urinary system
‫الجهاز البولى‬
Genital system and udder ‫الجهاز التناساى‬
Locomotor system
‫الجهاز الحركى‬
Central nervous system
‫الجهاز العصبى‬
Hair, skin, SC tissue, and visible mucous membranes
‫فحص الشعر والجلد والنسيج تحت الجلد واالغشيه المخاطية‬
When compiling the case history, questions will have been asked about:
- Previous occurrences of skin disease on the farm,
- The density of cattle within the buildings,
- Care of the hair coat (whether regular grooming, shearing,
washing or dipping is carried out),
- Type of bedding,
- Possibility of injury,
- Whether any dressing has been applied to the skin (disinfectant,
antifungal agent, anti-parasitic agent, etc.).
Hair
‫فحص الشعر‬
 Rough or shaggy coat (prolonged nutritional deficiency or chronic
parasitic infestations).
 Photosensitization
 Flealthy hair: As a result of sweat & sebaceous glands secretions.
 Dull coat: Due to Underproduction of sebum (asteatosis).
 Hairs covered with bran: Overproduction of sebum (seborrhoea)
or dandrof (as if bran had been scattered over it).
 Alopocia: Alopocia is loss or shedding of hair. It may be regional
or general alopecia. Louse and mange mite infestation.
11
Skin “the skin is the mirror of health”
‫فحص الجلد‬
 Localized (itching) pruritus (ectoparasitosis, particularly mange).
 Persistent, severe, generalized pruritus (pseudorabies).
 Skin thickening (sarcoptic mange, parakeratosis (zinc deficiency).
 Dermatitis (inflammation of the skin)
 Wounds, necrosis of small or large areas of skin, skin ulcer
 The ectoparasites include: Ticks and mange mites (Sarcoptes
bovis, Chorioptes and Psoroptes).
‫فحص النسيج تحت الجلد‬
Subcutaneous tissue (subcutis)
1.
2.
3.
4.
5.
6.
Dehydration (skin fold test)
The disappearance of fat deposits in severe emaciation
Oedema (major disturbance of venous blood flow to the heart).
Hypoproteinaemia (bottle jaw).
An abscess
A haematoma (accumulation of blood under the skin).
7. Subcutaneous emphysema (accumulation of air or gas).
8. Parasites: 3rd -stage larvae of the ox warble fly (Hypoderma bovis)
‫فحص االغشيه المخاطية‬
Visible mucous membranes
1. Yellow staining from deposition of bile pigments (Jaundice).
2. Non-haemolytic anaemia is manifested by extreme paleness.
3. Bluish-violet (cyanosis) occurs during circulatory disorders.
4. Reddening is usually due to local or general inflammation.
5. Petechtae (in the various forms of haemorrhagic diathesis).
6. Nodules (papular stomatitis,
7. Vesicles (vesicular stomatitis, infectious pustular vulvo-vaginitis),
8. Aphthae (foot and mouth disease).
9. Erosions (as in infectious rhinotracheitis).
10.Necrosis (as in malignant catarrhal fever and BVD.
11.Deep ulcerative defects surrounded by a raised edge (ulcers).
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Examination of the lymphatic system
Lymph nodes
‫فحص الجهاز الليمفاوى‬
‫الغدد الليمفاوية‬
The body lymph nodes are normally:
- Flaccid or tautly elastic,
- Easily displaced and
- In one piece.
During inspection and palpation attention should be paid to:
- Increase in size,
- Tenderness,
- Firm consistency,
- Nodule formation,
- Adhesion to surrounding tissues, and
- The occurrence of accessory lymph nodes.
Examination of lymph nodes:
‫فحص الغدد الليمفاوية‬
o Lymph nodes of the head and neck
Mandlbular lymph nodes
Parotid lymph nodes
Retropharyngeal (suprapharyngeal) lymph node
The external retropharyngeal lymph nodes.
o Prescapular (superficial cervical) lymph nodes
o Prefemoral (subiliac) lymph nodes.
o Mammary lymph nodes
Examination of the circulatory system ‫فحص الجهاز الدورى‬
Heart ‫القلب‬
In cattle the heart occupies a ventral position in the thoracic cavity
between the 3rd and 6th pairs of ribs. The apex of the heart points
slightly backwards and to the left, so that about three-fifths of the heart
muscle is on the left of the midline, and the remainder on the right.
Consequently the main site for examining the heart is on the left side.
Examination of the heart comprises:
Observation,
Palpation,
Percussion,
Auscultation
‫المالحظة‬
‫التحسس‬
‫الصدم أو الطرق‬
‫السماع بإستخدام السماعه‬
13
‫المالحظة‬
Observation:
Tremor in the chest wall (the heart beat is so exaggerated)
Congestive oedema in the dewlap (severe cardiac insufficiency).
Palpation:
‫التحسس‬
Action of the heart can be felt with the finger tips by laying the left hand
flat against the chest inside the left elbow at the fourth (if necessary 3rd
and 5th) inter-costal space. Normally the apex beat cannot be felt in fat
cattle, but it can be felt in lean cattle. You have to notice the following:
Displacement,
Weakening,
Strengthening or
Arrhythmia.
Percussion: ‫الصدم أو الطرق‬
Using a small soft-tipped hammer and a pleximeter or by using the
fingers. On the left side of healthy, adult cattle this area is the size of the
palm of a hand, while on the right side it is smaller or indistinct. You
have to notice the following:
-
Pulmonary emphysema (cardiac dullness is smaller).
Hydropericardium (extensive and pronounced dullness).
Pericarditis (dullness cover area in front of, and behind scapula).
Hydrothorax (Increase in intensity & extent of cardiac dullness).
Portion of the reticulum in the thoracic cavity (complete dullness
behind the heart).
- Sensitivity of the patient to percussion in the heart region.
Auscultation ‫السماع بإستخدام السماعه‬
Using tubed phonendoscope (stethoscope). The chest piece should be
pressed firmly against the chest on the left side in 3rd & 4th intercostal
space beneath and above the tip of the elbow. Normal heart sounds:
1. First (systolic) heart sound: longer, deeper and louder than 2nd.
2. Second (diastolic) heart sound is shorter, higher and more gentle.
- Heart sounds is (bub – dup), equivalent to lub - dupp in man.
- Listening to cardiac function is (F-I-R-D-A= frequency, intensity,
rhythm, demarcation & any adventitious sounds).
14
Heart frequency
‫معدل نبضات القلب‬
Normal heart rate
Heart frequency (heart rate) usually coincides with that of the pulse.
Tachycardia
Increase of the heart rate. A rate of over 90 in resting, adult cattle, over
100 in young cattle or over 120 a minute in calves denotes tachycardia, a
symptom of circulatory disorder.
Bradycardia
Slowing of the heart rate in cattle to less than 65/minute (bradycardia).
‫شدة نبضات القلب‬
Intensity of the heart sound
Intensity of the heart sound is normally strong and even; upon
auscultation the sounds are clear and of a uniform strength.
A more or less pronounced increase in the first heart sound occurs
during increased heart work of physiological or pathological
origin (bodily exertion, psychic excitement, anaemia, cardiac
insufficiency).
Heart rhythm
‫إنتظام نبضات القلب‬
Normal heart rhythm
Heart rhythm is normally regular with no change in the duration of the
first and second heart tones nor in systole and diastole at the same heart
rate. Abnormal heart rhythm:
Duplication of the second heart sound
Pronounced cardiac arrhythmia
Demarcation or distinctness of the heart sounds
‫حدود نبضات القلب‬
- Demarcation or distinctness of the heart sounds refers to the
clarity of onset and termination.
- Indistinctly terminated (blurred, rolling) heart sounds may be the
first sign of incipient valvular endocarditis. Occurring with
tachycardia, such sounds are an indication of deteriorating heart
function.
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Adventitious heart sounds (murmurs)
‫عارض نبضات القلب‬
- Adventitious heart sounds (murmurs) comprise any that are
additional to the first and second sounds, regardless of the nature
of the sound.
- They are almost invariably pathological features, and are divisible
into endocardial and exocardial (or pericardial) murmurs.
- Adventitious sounds are also caused by malformations in the
heart, such as persistent foramen ovale (organic murmur).
16