1
Comprehensive notes on diseases of canine
Delivered By: • Dr. Tasleem Ghori
Composed by: • Adnan Aslam
1
2
Table of Contents
Serial No.
1
2
3
4
5
6
7
Disease
Leptospirosis
Rabies
Canine Distemper
Canine parvo disease
Infectious canine Hepatitis
Lyme Disease
Canine Ehrlichiosis
Page No.
3
5
7
9
11
13
14
2
3
Leptospirosis
Etiology:





Leptospira
Leptospira
Leptospira
Leptospira
Leptospira
interroganus
canicola
icterohemorrhagiae
pomona
grippotyphosa
Canicola: Dogs are considered as reservoir host. It causes persistent infection and chronic
disease in the dogs. They persist in the proximal convoluted renal tubules. Found in acute,
chronic and carrier form.
Icterohemorrhagiae: cause acute type of infection.
Epidemiology: Most commonly found in late summer & early fall.
Transmission:




Contaminated water/pond
Urine of infected animal
Venereal transmission
Transplacental transmission
Source of infection:



Rat urine
Dead fetus and placenta
No gender specificity. Common in Germen Shepherd
Pathogenesis:
Entry by ingestion. Affect kidney & liver also cause disseminated intravascular coagulopathy
and encephalitic form.
Clinical Findings:
Incubation period is 4-12 days, in acute cases it is of 2 days. Kidney failure in 80-90% cases.
Generalized Signs:
3
4

Mild fever (103-104°F), anorexia, depression, lethargy, arthralgia (pain of joints),
myalgia (pain of muscles) due to which animal reluctant to move. Occulo-nasal
discharge.
Specific signs:
Kidney:





Uremic signs: vomiting, vomitus may contain some blood and vomiting may lead to
dehydration.
Lumber pain due to remomegaly.
Ulceration on the tip of tongue and necrosis
Hematuria, urine color will be brownish chocolate.
In mild cases of nephritis there will be polydypsia and polyuria while in acute cases
there will be oliguria and anuria.
Hepatic Form:
Mostly observed in acute cases in which along with the generalized systemic signs there
will be
 Icterus
 Bilirubinuria due to polystasis and necrosis
In per acute form there will be



Malena (blood in feces)
Pulmonary hemorrhage due to which there will be pneumonic signs.
Abortion, anemia, emaciation, pale mucous membrane and conjunctiva.
Encephalitic Form:

Circling. Most commonly observed in cattle.
Diagnosis:



Azotemia (increased blood urea nitrogen)
In case of kidney involvement
High level of ALT, ALP & AST
Microscopic agglutination test
1:800 show high titer
Treatment:
4
5






Pencilline G 25000-40000IU/kg (not effective now)
Ampicilline 22mg/kg IM, every 6-8 hours for two weeks
Enrofloxacine 2.5-5mg/kg IM
First generation cephalosporins are not effective against leptospira
Doxycycline 5mg/kg PO b.i.d for two weeks.
Supportive therapy (liver tonic, fluid therapy)
Control:



Vaccination
Rodent control
Proper cleaning of kennel
Rabies
Disease of all worm blooded animals. It is a disease of zoonotic importance which is
characterized by acute type of encephalomyelitis. Can affect any mammal.
Etiology: Lyssa virus of Rhabdoviridae
Epidemiology: Sporadic cases are found (through bite)
Transmission: dog bite
Reservoir: dog, lab animals, racons, bats(in Africa)
Virus has neurotropism. Surface Glycoprotein (G protein) on virus serves as neurotoxin and
helps the virus to bind with its receptors present on lipid membrane of nerve cells. The virus
descends down via cranial nerve, supplying the salivary glands. When affected dog bite any
mammal, it transmit the virus.
Pathogenesis:
Introduction of virus via saliva (dog bite) into the tissues. Then initial multiplication of the virus
in local tissues. After residing in the tissues they move to the neuro-muscular junction and
enters into peripheral nerves and via retrograde intra-axonal movements the virus travels to
the spinal cord and from spinal cord it ascends to the brain and mainly cerebral part of brain is
affected. There, further multiplication takes place and negri body formation occur. Then they
descend down to the salivary glands via cranial nerves and then from salivary glands, virus droll
from saliva.
5
6
Virus travels at the speed of 100mm/day via axon. Maximum speed is 400mm/day.
No aerosol transmission has observed.
Clinical findings:
Incubation period in cats is 26 weeks while in dogs 4-24week. Incubation period depends on;
1. Degree of innervations at the site of bite
2. Distance of bite site from spinal cord
3. Amount of inoculum of virus
Signs: first thing is acute behavioral changes, anorexia, restlessness, hyper-excitability and
change in temperament.
Divided into three phases;
❶ Prodromal






First 1-3 days.
Anxiety, solitude, excessive wound licking.
Difficulty in apprehension (understanding), slow corneal and palpebral reflexes &
pupillary dilatation.
❷ Furious
2-4 days. Mainly involvement of forebrain.
Restlessness, excitation, irritable response, excessive barking at inanimate objects, pica
like condition.
Photophobia, prefer to live in dark, isolate space.
❸ Dumb/Paralytic
Paralytic signs are observed when there is involvement of whole nervous system. Paralysis is
progressive. Lower motor nerve paralysis.




Change in bark due to laryngeal paralysis.
Hypersalivation and frothiness due to pharyngeal paralysis.
Masticatory Paralysis (dropped jaw)
Paralysis of respiratory muscles result in coma and death.
Diagnosis:


On the basis of clinical signs
Dog bite history
6
7


Serological test [fluorescent antibody technique (FAT)]
Keep susceptible dog under observation for ten days. If rabid, dog will die.
Treatment:



Vaccination
Wash bite area with antiseptic soap
When signs appear then no treatment
Canine Distemper
Highly infectious, contagious and systemic.
Etiology: Morbilli virus (canine distemper virus)
Characterized by leuckopenia , diphasic fever, GIT & Respiratory catarrh.
Host:
1. Canidae
2. Mustalidae
a. Ferrets
b. Minks
c. Skunla
Age susceptibility:
Below six month of age
Intensity of Infection: depend on
1. Age of host
2. Immune status of the host
3. Virulency of virus
Transmission:
1. Aerosole
2. Feces
3. Urine
Heat susceptible hence more found in cold environment.
7
8
Pathogenesis:
Invasion of virus and localize in the lymphatic tissue (tonsils, retropharyngeal lymph nodes,
spleen, bone marrow and thymus)
Target mononuclear lymphocyte, GIT, kupffer cells of liver, epithelial cells of intestine nad
mesenteric lymphnodes. Then viremia. After viremia if immune status is poor then;




Affect respiratory system (nasal discharge, coughing)
Nervous system (optic neuritis which will result in blindness)
GIT (enteritis, diarrhea, dehydration)
Urogenital signs (abortion)
Clinical Findings:





Diphasic/transient fever. Initially temperature rises up to 104°F then descend down and
second phase of fever appear which persist for one week.
Leuckopenia which result in severe immune suppression.
Serous nasal and ocular discharge which become muco-purulent due to secondary
bacterial infection. Dry cough which later on become muco-purulent
GIT signs: vomiting and diarrhea which lead to severe dehydration.
Nervous signs: acute type of encephalomyelitis which result in involuntary twitching of
leg or facial muscles, one or group of muscles may be involved. Chorea is the
involuntary muscular spasm of flexor muscle.
There is hyperkeratosis of foot pad due to which this disease is known as Hard Pad
Disease
Those pups which show skins signs also exhibit nervous signs.
Paresis of hind legs then extend to forelegs (tetraparesis)
Chewing gum fits. It is characterized by salivation and involuntary chewing movements
Epileptic seizures in which dog fall down on the ground and paddle its legs.
Involuntary urination and defecation.
In pups there is appearance of pustules on the ventral aspect of the abdomen.
Appearance of pustule indicate favorable prognosis.
Optic neurosis result in blindness and eye color become pink and grey due to necrotic
foci of retina.
Sometimes there is bony over growth of teets in pups.
Diagnosis:

Clinical signs
8
9


Isolation of virus from nasal secretion, feces and urine.
Serological test (ELISA)
Treatment:
No specific treatment against viral infection.avoid secondary bacterial invasion by broad
spectrum antibiotics.





As Vomiting or diarrhea hence give Ringer solution
Nervous signs like fits or seizures, inject diazepam (valium)
Diphasic fever hence inject antipyretic (Dicloran)
Follow proper vaccination schedule.
Canine distemper serum is also available. Inject that.
Chronic Distemper
Found in old dogs.



Progressively develop.
Atexia
Head pressing & hypermetria (uncontrolled movements)
Canine Parvo Disease
We perform vaccine against this disease at weaning age.
Susceptible age: 6-8 weeks of age. May also found in adults.
Clinically characterized by GIT signs.
Etiology: Canine Parvovirus II
Can bear a wide range of environmental temperature and pH. Thermostable.
Susceptible breeds: Roh wiellar, American pitbull terrier, Germen shepherd & Doberman.
Not common in small breeds. Mortality 16-48%.
Source & Transmission:



Fomites
Direct Transmission (Horizontal & vertical)
Shed in feces at 3rd day of infection up to three weeks.
9
10
Pathogenesis:
Entry of virus via oropharynx route. Replicate in lymphoid tissue of the pharyngeal area. then
viremia. Affect rapidly growing cells like bone marrow, lymphopoitic tissue crypts and
endothelial cells of intestine (jejunum and ilium).
Result in;




Lymphopenia and neutropenia
Immuno suppression
Villi destruction in intestine, epithelial necrosis and hemorrhagic enteritis.
Hemorrhagic diarrhea due to secondary bacterial infection of E. coli & Clostridium
perferingens.
Clinical Findings:
Depend on
1. Stress on animal
2. Infective dose
3. Secondary infection.
Incubation Period: 3-8 days.
Two clinical forms.
1. Myocardial Form:
 Fond in pups below six week of age.
 Due to necrosis of myocardium there will be acute cardio-pulmonary failure.
 Pulmonary edema
 Cyanosis of mucous membrane
 Vascular collapse
2. Gastro enteritis Form:
 Between 6-20 weeks of age.
 Fever (104-106°F)
 Anorexia, profuse vomiting and acute onset of diarrhea. Feces color will be
yellowish grey, may contain mucous and blood. This type is more common in
males than females.
Diarrhea ultimately leads to dehydration, electrolyte imbalance and lethargy.
If severe dehydration then there may be nervous signs.
Death within few hours.
10
11
Treatment:









Vaccine
Isolate the affected animlas
Administration of electrolyte, Ringer solution.
5% dextrose with addition of Potassium chloride give better result.
If vomiting is not severe then give ORS.
Antiemetic drug: Metoclopramide @ 0.2-0.5mg/kg .
Sedative compound: chlorpromazine @ 0.2-0.5mg/kg
Antibiotics: 1st and 2nd generation cephalosporins.
Gastric protectants:
Cemitidine @ 5-10mg/kg IV. Repeat after 6 hours.
Remitidine @ 2-4mg/kg
Antipyretic
Infectious Canine Hepatitis
Worldwide distribution. Highly contagious. Clinically characterized by severe depression,
biphasic fever, leucopenia and increased bleeding time.
Etiology: Canine Adenovirus type I
Antigenically related to Type II which cause tracheobronchitis in dogs.
Transmission: Through urine, feces and sliva.
This virus is shed in urine for 6 months. Inactivated at 50-60°C for 5 minutes.
Pathogenesis:
Ingestion of virus through oropharynx route then it multiply in lymphoid tissue (tonsilar crypts
and cervical lymph node). Then viremia . After viremia it affect various body organs.
1.
2.
3.
4.
5.
6.
Liver: main target cells are kupffer cells and cause acute type of hepatitis.
Kidney: affect glomerular endothelium
Spleen: affect spleenocytes and endothelial cells of spleen resulting spleenomegaly.
Lungs: affect pulmonary endothelium and result coughing.
Eyes: cuase blu eye (due to circulatory immune complexes) & conjunctivitis.
Brain: cause encephalitis
11
12
Clinical Findings:
Mortality rate is high in young pups. Incubation Period is 4-9 days.
General signs include biphasic fever (temperature rises up to 104°F), lethargy and polydypsia.
GIT signs:


Vomiting, diarrhea and severe abdominal pain. On palpation animal feel pain.
Hypremia and ptechial hemorrhages of oral mucosa.
Respiratory signs:



Serous nasal and ocular discharge.
Tracheitis, pharyngitis and coughing.
Sub cutaneous edema of head, neck and trunk. Disseminated intravascular
coagulopathy which lead to hematoma development. Further there will be increased
bleeding time.
Occular Signs:





Bilateral corneal opacity
Conjunctivitis
Hydrophthalmus
Blephrospasm
Glaucoma, ulcers and impairment of vision.
Brain:

Damage the forebrain endothelium which leads to some nervous signs like convulsion,
paralysis etc.
When nervous signs appear then prognosis is poor.
Clinical Pathology:
Treatment:


Fluid therapy
If prolonged period of off feed then dextrose 5%
12
13







Broad spectrum antibiotics (Cephalosporins)
Liver tonic (Hepasel etc)
Antiemetics
As bleeding time increased hence give Vitamin K.
In case of glaucoma give atropine
Anti-diarrheal (Bismol)
Avoid corticosteroids
Lyme Disease/Borreliosis
Etiology: Borrelia burgdorferi
Very common in all domestic animals. Zoonotic. Transmit through ticks.
Epidemiology: Asia, Africa, USA, Europe
Transmission: through three host ticks
1. Ixodes pacificus (west coast of America)
2. Ixodes scapulari
Rodents act as reservoir host. Seasonal occurrence (spring & fall)
Clinical Findings:
Four forms;
1. Limbs and joints Form:
 Fever, lameness and lethargy. On palpation of joint there will be painful swelling.
 Lymphadenopathy.
2. Cardiac Form:
 Bradycardia
 Abnormality in the conduction system to the heart.
3. Neural Form:
 Facial paralysis
 Seizures
4. Renal Form
Second most common disease of dogs. Characterized by;

Uremia
13
14



Hyperphosphatemia
Protein loosing nephropathy
Peripheral edema
Treatment:



Prolonged therapy of antibiotics for two weeks (Pencilline or Tetracycline)
NSAID for joint pain (Dicloran)
Tick control
Canine Ehrlichiosis
Etiology:


Ehrlichia canis
Chaffeensisi
Transmission:
Brown dog tick/Rhiphicephalus sanguinus
Clinical Findings:
Two Forms
1. Acute
2. Chronic
Mainly affect T-cells, monocytes and macrophages.
1. Acute Form:
 Reticuloendothelial hyperplasia
 Spleenomegaly
 Lymphadenopathy
 Thrombocytopenia
In response to above conditions there will be;




Fever, anorexia, depression,
Loss of stamina
Stiffness of limb, animal will be reluctant to move.
Edema of limbs and scrotum
14
15
 Increase in respiration, coughing
 Self recovery is possible
2. Chronic Form:
 Glomerulonephritis
 Uveitis
 Meningitis due to cerebral hypoplasia, atexia, hyperaesthesia & paralysis.
Diagnosis:


Presence of ticks
Hematology (Increased lymphocytes, thrombocytopenia)
Treatment:





Drug of choice
Doxycycline @ 10mg/kg IV, once in day for 10-20 days
Tetracycline @ 22mg/kg b.i.d for 2 weeks.
Imidocarb dipropionate @ 5-7.5mg/kg IM, repeat after two weeks
Supportive therapy
Blood transfusion
The End
15