EVOLUTION

ANIMAL BREEDS

DISEASES

MEDICATIONS

FOOD/FEED

BEHAVIOUR

EXOTIC ANIMALS

SPECIAL SECTION

Viral Disease - Rinderpest

Synonyms : cattle plague

Introduction:

Acute contagious viral diseases of cattle and buffalo characterized by necrotic stomatitis, gastro enteritis, dehydration and lymphocytolysis.

Animals affected:

Mainly cattle, Buffalo, but reported in sheep and Goat, Pigs

100% Mortality Exotic breeds

20-50 Mortality Indigenous breeds

Etiology

Morbili virus, PARAMYXO family - Immunologically and pathologically related to CD and Measles.

Route of infection

Virus excreted in body secretions

Ingestion of contaminated feed and water

Inhalation (or) Mechanical Transmission

Pathogenesis:

RP Virus - Affinity for lymphoid tissue and mucous membrane of alimentary tract

Lymph Node - Pyknosis and Karyorrhexis of Spleen & nuclei of lymphocytes (necrosis)

Peyer patches - Infiltration of Macrophage, plasma cells

- Multinucleate Giant cells with eosinophilic inclusion

- Edema and congestion

Incubation stage

Infection, Proliferation in LN, haematogenous spread other lymphoid tissue mucous membrane of Respiratory, Alimentary Tract,

Prodromal stage

Fever (104 F), dull, depressed, Anorexia Rumination Photophobia, serous nasal and lacrymal discharge mucus coated feaces

Mucosal stage

Cardinal signs of RP erosion and Necrosis of mucous membrane of oral cavity

Clinical signs

Oral lesion, Body temperature, diarrhea, watery large volume of feces with mucus With blood Necrotic epithelium , Signs of dehydration

Animal may die (or) proceed to convalescent stage

Convalescent stage:

  • » Resolution of mucosal lesions
  • » Diarrhea for sometimes

Lesions

Upper third of esophagus also show lesions

Rumen, reticulum and omasum - rare

Abomasum-pyloric region has necrotic foci, Hemorrhagic streaks, thick and edematous folds, raw blood will notice.

Lesion in Small Intestine is not so severe

Duodenum and Ileum - Hemorrhage / Erosions

Peyers patches - Necrosis, Deep ulcers with heamorrhagic borders

Large intestine - Ileocaecel valve, caeco colic junction, Rectum- Hemorrhage, ulcers, pseudo membrane deposit, Streaks of Congestion/ Haemorrhage on the folds of mucosa of Intestine -'ZEBRA MARKINGS'

LIVER: CVC, Petechiae

Pulmonary and cardiac lesions

Petechiae and erosions of URT, Larynx

Tracheal hemorrhages

Alveolar and Interstitial emphysema

Sub epithelial and Sub endocardial haemorrhages

Eosinophilic cytoplasmic inclusion bodies form in the mucosal epithelial cells and giant cells. Intra nuclear inclusion bodies are rare.

Diagnosis:

Symptoms and lesions

Complement fixation test (CFT)

Agar Gel Precipitation Test (AGPT)

Virus isolation and diagnosis on tissue cultures

Using specific cDNA probes, isolates of rinderpest and PPR viruses can now be differentiated

Polymerase chain Reaction (PCR)

Differential diagnosis

Bovine virus diarrhea

Foot-and-mouth disease

Malignant catarrhal fever

Peste des petits ruminants.

Treatment

None

Control:

Surveillance and annual vaccination with tissue culture vaccine in endemic areas, eradication by slaughter and rigid quarantine during outbreaks in non-endemic areas.


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