BOVINE VIRAL DIARRHOEA

Synonyms: mucosal disease

It is characterized by high rise of temperature, diarrhea, erosive lesion in mouth, esophagus,rumen abomasum and intestine

Etiology:Pestivirus , Family – flaviviridae

Mode of transmission:

  • Direct and indirect contact
  • Incidence more in crowded herd
  • Virus present innasal secretions, oral discharge, urine
  • Other source like transport vehicles,farm appliancescontaminated feed and water
  • Sheep and swine have no role in disease transmission
  • Calves harboring cytopathic strain act as principal source of infection

 

Pathogenesis:

  • Virus on enter to body contact with mucosal lining of mouth or nose and replicate in epithelial cells
  • Predilection site of virus are
    • Palatine tonsils
    • Lymphoid tissues
    • Epithelium of oropharynx
  • Goes to bloodstream and develop viraemia 2–4 days after exposure
  • Goes to M.M of alimentary tract and buccal cavity and causeInflammatory changes and edemaEnteritisStomatitis destruction and erosion of Payer’s patches and lymph nodes

 

 

Clinical signs:

  • Incubation period: 1-21 days
  • Three forms of clinical signs are noticed

Acute form:

  • Rise of temperature 105˚- 107˚F may be biphasic
  • Anorexia
  • Depression
  • Polypnoea
  • Mucoid then muco purulent nasal discharge
  • Moist coughing
  • Muzzle rough, dry and crustated
  • Conjunctivitis
  • Mucopurulent ocular discharge
  • Corneal opacity
  • Profuse foul smelling watery faeces
  • Ulceration of oral mucosa, tongue, palate and gum
  • Profuse salivation
  • Abortion
  • Foetal abnormalities and malformed
  • CNS derangement
  • Lameness
  • Muscular tremor,weakness,incoordination,nystagmus
  • Animal die due to septicemia and dehydration

Mild form:

  • Fever of short duration
  • Loss of milk yield
  • Transient diarrhea
  • Infrequent mouth lesion
  • Inapettance
  • Nasal discharge
  • Enlargement of superficial L.N

 

Subacute/chronic form

  • Retarded growth
  • Loss of body weight
  • Emaciation
  • Rough skin coat
  • Intermittent diarrhea
  • Chronic buccal lesion
  • Chronic bloat
  • Distorted hooves
  • Chronic erosion of skin

 

Diagnosis:

  • Typical clinical sign
  • Gross and microscopic lesion
  • Leucopenia
  • CFT
  • Virus Neutralization test
  • Immunofluorescence test
  • ELISA
  • CFT

Treatment:

  • No treatment for viral infection
  • Supportive therapy
  • Fluid therapy
  • Antibiotics and chemotherapy
  • Whole blood transfusion