Peste des petits ruminants (ppr), Biology

Assignment Help:

Peste des petits ruminants (PPR) is an acute, highly contagious viral disease of goats and sheep caused by peste des petits ruminants (PPR) virus which belongs to the genus Morbillivirus of the family Paramyxoviridae. The disease is characterized by fever, anorexia, necrotic stomatitis, diarrhoea, oculo-nasal purulent discharge and respiratory distress. Infection is mainly transmitted by inhalation or through conjunctiva and oral mucosa. PPR virus penetrates the retropharyngeal mucosa and enters the blood. Virus localizes in alimentary, respiratory and lymphoid system and causes diahorrea, dehydration and death.PPR is rinderpest like disease in Africa and Asia and highly fatal in goats and less so in sheep. Case fatality rate in goats is 55-85% and in sheep it is less than 10%. Goat kids aging between 4 months and 1 year are most susceptible. The disease was first described in West Africa in 1942. In India, it was first reported in Tamilnadu in the year 1989 and subsequently from other states of India. The disease was first confirmed in Andhra Pradesh in 1991 using specific molecular probes. Since then several outbreaks of rinderpest like diseases in sheep have been attributed to this virus. Cattle and pigs can have antibodies against PPR but do not come down with disease upon inoculation of PPR virus.


Epidemiology:
The transmission of virus occurs through contact mainly through inhalation of aerosols produced by sneezing and coughing fomites;    bedding may also contribute to the onset of an outbreak. Ocular, nasal, and oral secretions and feces are potent sources of virus. Infected animals can transmit the disease during the incubation period as well as during the recovery phase.


Clinical signs: Disease occurs in 2 forms; acute form which is common in goats especially in kids and subacute form which is common in sheep with mild clinical symptoms.The disease usually appears in an acute form, with an incubation period of 4 to 5 days followed by a rise in body temperature to 106° F (40-41° C). The temperature usually remains high for about 5 to 8 days before slowly returning to normal. Affected animals appear dull with a dry muzzle, and reduced appetite. From the onset of fever, mo st a nimals have a se rous na sal discha rge , which pr ogre ssively be comes mucopurulent. At this stage, animals suffer from respiratory distress, and there is sneezing in an attempt to clear the nose. The conjunctiva usually becomes congested and there may be profuse catarrhal conjunctivitis resulting in matting of the eyelids. Necrotic stomatitis is common. Death usually occurs after a course of 5 to 10 days. Bronchopneumonia, evidenced by coughing and characterized by consolidation, is a common feature in the later stages of PPR. Pregnant animals usually abort.


Diagnosis: Diagnosis is based upon clinical and necropsy findings supported by viral isolation in Vero and primary cells of ovine origin and characterization using RT- PCR to distinguish from rinderpest virus. Competitive ELISA based on monoclonal antibodies for detection of antigen is used.
Prevention and control: Vaccination; presently live attenuated tissue culture vaccine (Sungri 94 strain virus) produced by IVRI Mukteswar and from Anasur strain by TANUVAS are effective in controlling PPR in the country.

 


Related Discussions:- Peste des petits ruminants (ppr)

State about the blood ocular barriers of the eye, State about the blood ocu...

State about the blood ocular barriers of the eye? Blood Ocular Barrier: All vascular beds of the eye are highly permeable to lipoid soluble substances (oxygen, carbon dio

Nutrients and the soil, Nutrients and the Soil Early experiments on mi...

Nutrients and the Soil Early experiments on mineral uptake were performed by Hoagland, Stout and Amon in 1923. They showed that minerals were taken up from the soil primarily

Under which environments do echinoderms live, Q Under which environments do...

Q Under which environments do echinoderms live? Echinoderms are marine animals and they live in salt water.

Rejection reaction, Rejection Reaction For rejection reaction the phys...

Rejection Reaction For rejection reaction the physiological and biochemical processes are set in the pistil by the recognition reaction specific to the type of pollen that lan

Explain retrograde peri-implantitis, What is retrograde peri-implantitis? ...

What is retrograde peri-implantitis? Retrograde peri-implantitis has been described by Misch as implant failure probably due to bone microfractures caused by premature implant

Decomposers, 5 beneficial effects of decomposers and 2 harmful effects

5 beneficial effects of decomposers and 2 harmful effects

Formation of gametes, In his experiments, Mendel noted that when two traits...

In his experiments, Mendel noted that when two traits are involved in a genetic cross, they are inherited independently of each other. The reason for this is that A. genes on the s

Internal mammary artery-long term patency, Internal Mammary Artery (1MA) : ...

Internal Mammary Artery (1MA) :  This is an excellent graft. When left internal mammary artery (LIMA) is anastomosed to LAD, which has more than 70 per cent block, patency at

Chemical weathering-formation of soil, Chemical Weathering The rocks wh...

Chemical Weathering The rocks while getting disintegrated may also undergo chemical change. Water is an important agent in bringing about chemical changes due to dissolution or

Define stress factors - etiological risk factors in cancer, Define Stress F...

Define Stress Factors - Etiological Risk Factors in Cancer? Emotions playing a part in malignancy are not a new idea. But these relationships are extremely difficult to measure

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