Bluetongue, Biology

Assignment Help:

Bluetongue

Bluetongue (BT), a viral disease, transmitted by Culicoides midges, is an infectious, non-contagious disease of ruminants including sheep, goat and cattle, is characterized by congestion, oedema and haemorrhage in the affected animals. The virus belongs to the genus Orbivirus in the family Reoviridae. There are 24 different virus serotypes identified so far.


Epidemiology: Bluetongue was first reported by Hutcheon (1881) as epizootic catarrh fever in Africa. From Africa, the disease spread to American continent and then moved toward Europe and Indian subcontinent. In Indian subcontinent, BT was first reported from Pakistan in 1959. Subsequently, the first outbreak of BT in India was recorded by Sapre in 1964 among sheep and goats in Maharashatra state. Although indigenous sheep are affected but exotic and crossbreds are severely affected. In India, BT is noticed at the end of southeast monsoon and in the beginning of northeast monsoon when the breeding and population of culicoides are at peak. BT virus is transmitted by biological and mechanical vectors. Out of about 1000 species of Culicoides in the world, 7 have been recognized as biological vectors of BT. Sheep ked (Melophagus ovinus) act as mechanical vector (without viral multiplication). There are at least 24 serotypes of BT virus in the world. At least 14 of these have been reported from India.


Clinical signs: The symptoms consist of fever, lameness, oral lesions, emaciation and death. The disease is of seasonal occurrence. Virus enters the blood following the bite of insect and localizes in endothelium of oral cavity, nasal cavity, lamina and coronary band. Due to stagnation of blood in the vessels, the tongue appears cyanotic i.e. blue in color, giving the name as Blue tongue. Later on, necrosis leading to sloughing of mucosa resulting in ulcers on lateral borders of the tongue can occur.


Diagnosis: The diagnosis is based on the clinical signs, virus isolation and detection of antibodies by virus neutralization, complement fixation and fluorescent antibody tests.Treatment, prevention and control: There is serological evidence of the occurrence of this disease in almost all the states in India. Virus isolation has been done in some outbreaks. A live attenuated chicken embryo vaccine is available for the control of the disease and its application is recommended in endemic zones. Vector control is a very important programme in disease prevention. Work is in progress in India for the development of polyvalent killed vaccine.


Related Discussions:- Bluetongue

List a few applications of starches in the food industry, List a few applic...

List a few applications of starches in the food industry. A few applications of starches in the foods industry include thickener, a fat sparing agent, adhesive, binder,

What are the methods of foams, What are the methods of foams? There are...

What are the methods of foams? There are two basic methods in  the formation of foams i.e. a) whipping and b) condensation.

Illustrate the molecular composition of hemoglobin, Q What is the molecular...

Q What is the molecular composition of hemoglobin? Does the functionality of hemoglobin as a protein depend upon its tertiary or upon its quaternary structure? Hemoglobi

After purchasing - nursing software, After Purchasing The following po...

After Purchasing The following points should be considered for after purchase facilities. Avail of any training the software engineer or vendor may provide, even if it

Excluding development, tube feet,stone canal,medreporite and teidman;s body...

tube feet,stone canal,medreporite and teidman;s body notes

How do the repairing enzymes of the genetic system act, How do the repairin...

How do the repairing enzymes of the genetic system act? There are enzymes inside the cells that detect errors or alterations in DNA molecules and begin a repair of those errors

Pennetula, identifying characters of pennetula

identifying characters of pennetula

Explain about lyophilic, Explain about lyophilic If the affinity betwee...

Explain about lyophilic If the affinity between the dispersed phase and the medium is high, the dispersed phase is said to be lyophilic (solvent loving) or hydrophilic, in the

Determine the term - epilepsy, Determine the term - Epilepsy In epileps...

Determine the term - Epilepsy In epilepsy, a person suffers from recurrent seizures of various types that register on an electroencephalogram and are associated with disturbanc

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd