The document discusses various mite infestations in rabbits, detailing the etiologies, transmissions, and clinical signs associated with different types of mites including Cheyletiella and Sarcoptes scabiei. It also covers the West Nile virus affecting wild animals, including its transmission cycle, affected species, clinical signs, and histopathological findings. Diagnosis methods for both conditions are highlighted, such as microscopical examinations and various serological tests.

1. MITE INFESTATION IN
RABBITS
Presented by
Jisha shaji
22- BVM- 037

2. FUR MITES
•2 genus
Cheyletiella : C. parasitavorax ( most common)
C. yasguri
C. blakei
Listrophorus : L.gibbus

3. CHEYLETIELLA PARASITAVORAX
Etiology : noninvasive fur mite of rabbits
Transmission: Direct contact, Numerous in intrascapular
region
Pathogenesis:The mite remains in association with the keratin
layer of skin and feeds on tissue fluids.
Clinical signs: Fur falling off in clumps with erythema & flaking
of underlying skin
Diagnosis : Microscopical examination Mites are ovoid or
saddle shaped with large palps and pedal combs.

5. PSOROTOPES CUNICULI
Etiology: Non burrowing ear mite of rabbits causing “Ear
Canker”
Distribution: External ear canals , spread to face, neck and
legs.
Transmission: Direct contact
Pathogenesis :Live on the surface feeding on lipids, keratin,
crusts and cerumen.
Clinical signs: Light to heavy brown crusts in outer ear canal ,
head shaking, weight loss, decreased productivity, secondary
infection result in torticollis.
Diagnosis: Microscopical examination of ear crusts and swab.

7. LEPORACARUS GIBBUS
Etiology: small, non- burrowing, obligate parasite.
Distribution: Entire body, concentrated in rump.
Transmission: Direct contact
Pathogenesis: The life cycle of the parasite is characterized by
complete metamorphosis and occurs entirely on rabbit coat. It
feeds on sebum and skin epithelial cells.
Clinical signs: Moist dermatitis in back, groin and ventral
abdomen.
Diagnosis : Microscopical examination
Mites are brown, ovoid with short ventrally directed legs.
Males have posterior clasping organ.

9. SARCOPTES SCABIEI
Etiology: Small, burrowing mite, also referred as itch or scab
mite
Distribution: Ears, nose, feet and perineal area
Transmission: Direct contact
Pathogenesis: Mite burrows into the skin and feeds on the
host’s serum and epithelial tissues , resulting in severe skin
lesions.
Clinical signs: Intense pruritus, hair loss and abrasions as a
result of scratching, anemia, leukopenia.
Diagnosis: Microscopical examination of skin scrapings
The body of the mite is round and legs are very short.

11. WEST NILE FEVER IN
WILD ANIMALS

12. ETIOLOGY
• Family – Flaviviridae
• Genus – Flavivirus
• Single stranded RNA virus
Two Genetic lineage
• Lineage 1: 3 clades ( 1a,1b,1c)
• Lineage 2

13. TRANSMISSION
• Primary mosquito vector
• Culex sp.
• Tick vectors
• Overwintering of mosquitoes
• Birds

14. TRANSMISSION CYCLE

15. SPECIES AFFECTED BY WEST NILE VIRUS
Horses Black Bear Cattle
Goats Wolf Seal
Sheep Alpaca Cat
Dog Mountain goat Deer
Rabbit Alligator
Chipmunk Gray Squirrels
Skunk Bats
Crocodile Llama

16. PATHOGENESIS
• Virus entry via bite of a mosquito vector
• Replication of the virus occurs in dendritic cells
• Infected dendritic cells transport the virus to regional lymph nodes
• Primary viremia
• Infection of peripheral tissues such as spleen and kidney
• By end of the first week, virus cleared from serum and peripheral
organs

17. CLINICAL SIGNS
Birds
• Non-specific signs e.g. depression, anorexia, weakness, leg paralysis, weight
loss
• Neurological signs e.g. abnormal head or neck posture, ataxia, tremors,
circling, disorientation, paresis, visual impairment, dysphagia and seizures
Horses
• Neurological signs -weakness, paresis or paralysis, apparent blindness, lip
droop and tooth grinding
Other mammal
• Neurological signs

18. GROSS LESIONS
• Birds- splenomegaly, meningoencephalitis, and myocarditis
• Horses- oedema of supraorbital fossa, submeningeal edema,
congestion in spinal cord, oral and lingual ulceration,
pulmonary oedema.
• Raptors - Encephalitis, endopthalmitis, endocarditis
• Other mammal - No relevant gross lesions.

19. HISTOPATHOLOGY
• Birds: mild to severe encephalitis and meningitis, with
infiltrates and perivascular cuffing– mainly lymphocytes and
plasma cells.
• Myocarditis (mild to severe), sometimes nephritis, hepatitis,
pneumonitis
• Horses: Nonsuppurative encephalitis – neuronophagia ,
multifocal gliosis, perivascular cuffing.
• Other mammals: Nonsuppurative encephalitis and
myocarditis.

20. DIAGNOSIS
• Clinical signs and lesions
• Detection of antibodies: PRNT ( plague reduction neutralization test ),
ELISA
• Detection of antigen: RT- PCR, NASBA ( Nucleic acid sequence based
amplification), VecTest.

21. Thank you