Bovine Ephemeral fever
Vishnu Meena1, Bhavana Rathore2, Monika2*
- M.V.Sc. Scholar, Department of Veterinary Medicine, PGIVER, Jaipur
- Assistant Professor, Department of Veterinary Parasitology, PGIVER, Jaipur
*Corresponding author (drmoni23392@gmail.com)
Introduction:- Bovine ephemeral fever, popularly known as “Three day sickness” is an insect-transmitted, non-contagious viral disease of cattle and water buffalo that is present in Africa, the Middle East, Australia, and Asia. Inapparent infections can develop in buffalo, hartebeests, waterbuck, wildebeests, deer, and possibly goats, sheep, and gazelles. The disease is first reported in central Asia in 1867.
Now the disease is prevalent in India, Pakistan, Indonesia, Japan.
All the breeds of cattle are susceptible to this disease but the cattle age group, from 6 months to 2 years are more susceptible to this infection.
Etiology:- Bovine ephemeral fever virus (BEFV) is classified as a member of the genus Ephemerovirus in the family Rhabdoviridae (single-stranded, negative-sense RNA virus). The virus is bullet or cone shaped. The virus has got similarity in chemical and physical properties with the vesicular stomatitis virus. The virus is related to dengue fever in man.
Mode of Transmission:- The disease is transmitted by sand fly Ceratopogonidae family. Recently mosquitoes like culex, culicoides, have been suggested as a disease transmitter. Transmission dose not occur by direct contact from animal to animal or via their discharge.
Outbreak of this disease generally occurs in summer and rainy season. Virus spread appears to be associated with winds and transportation of animals.
Morbidity rates may be as high as 80%; overall mortality rate is usually 1%–2%.
Clinical findings:- The incubation period of disease is 2 to 10 days, may drop in morning. There is shivering and muscle trembling. Affected cattle disincline to move and if forced to move, they move with great difficulty with arched backed conditions.
Anorexia, reduction in milk yield, salivation, nasal discharge and lachrymation. Muscles of the affected limb become stiff, hard and painful. The animal show lameness, laminitis, may suspended rumination and grinding of teeth.
Some animal may adopt a posture similar to milk fever. Prolonged recumbency terminate to motor paralysis or aspiratory pneumonia due to regurgitation of ruminal fluid. Tachypnoea or dyspnoea, atony of fore stomachs, listlessness, biphasic to polyphasic fever (40°–42°C [104°–107.6°F]) are also observed.
Lesions:- The following are the most common lesions:-
- Polyserositis affecting pleural, pericardial, and peritoneal surfaces.
- Serofibrinous polysynovitis, polyarthritis, polytendinitis, and cellulitis.
- Focal necrosis of skeletal muscles.
- Pericardial sac may contain blood.
- Enlargement of lungs and swelling of alveolar walls.
Post disease complications:- Fall in milk yield, susceptible for mastitis, delay in oestrus, pneumonia due to prolonged recumbency and unfit for draught purpose.
Diagnosis:- based on clinical manifestation.
- Virus isolation test.
2.Complement fixation test.
3.Fluorescent antibody test.
4.Agar gel immune-diffusion test.
5.ELISA.
Differential diagnosis:- 1. Laminitis 2. Milk fever.
Treatment:- There is no specific treatment, only symptomatic treatment is there. Analgesic and antipyretics like phenylbutazone@ 4-8 mg/kgbwt.I/V used to reduce symtoms, Drenching of fluid and drugs should be avoided. To prevent secondary bacterial infection a course of parenteral antibiotics e.g. Tetracycline@5-10mg/kgbwt I/V or Enrofloxacin@5mg/kgbwt I/V along with B-complex vitamin cab be used. Calcium boro-gluconate may be needed in recumbent animals.
Control:- Vector control is the important key factor to control this disease. Various vaccines have been tried to control this disease, attenuated aluminium hydroxide adsorbent vaccine has been tried.
