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)

Amoeba, figure of contractile vacuole of amoeba

figure of contractile vacuole of amoeba

Function of noradrenaline in consciousness, Q. Function of Noradrenaline in...

Q. Function of Noradrenaline in consciousness? Increased level of noradrenalin is implicated in wakefulness. Locus coeruleus noradrenergic neurons decrease their rate of firing

How successful are you at synthesizing genes, How successful are you at syn...

How successful are you at synthesizing genes with really high G/C content? A: We have an extremely low failure rate, which is about one out of five thousand or ten thousand gen

History of quantitative impacts on biology, Show History of Quantitative Im...

Show History of Quantitative Impacts on Biology Quantitative threads have been woven into the fabric of biology since at least the late 19th century, when Malthus warned of the

What is oxidative phosphorylation, What is oxidative phosphorylation? O...

What is oxidative phosphorylation? Oxidative phosphorylation is  the process by which ADP is phosphorylated by Pi  to ATP  in  the  respiratory chain.

Denitrification - nutrient cycles, Denitrification - Nutrient Cycles N...

Denitrification - Nutrient Cycles Nitrates are readily leached from the soil and also lost through denitrification the process by which molecular or gaseous nitrogen (N 2 ) as

Exercise and medications in bronchial asthma, Exercise Stress or em...

Exercise Stress or emotional upset  Medications Aspirin, non-steroidal anti-inflammatory drugs(NSAIDs), beta- blockers(including eye drops), cholinergic dr

Explain the history of plant classification, Explain the History of Plant C...

Explain the History of Plant Classification? Before Darwin's theory of evolution and publication of his epoch making work 'Origin of Species' in 1959 no outstanding basis for

Explain typical components of a closed circulatory system, What are the typ...

What are the typical components of a closed circulatory system? The typical components of the closed circulatory system are the blood vessels within which blood circulates (vei

The formation of macro and micronuclei of daughter paramoeci, The formation...

The formation of macro and micronuclei of daughter paramoeci: Each exconjugant has a single micronucleus and four macronuclei. This type of exconjugant divides twice and f

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