What Is the Impact of Bluetongue Virus on Domesticated Animals and How Is This Important - Literature review Example

Impact of bluetongue virus on domesticated animals and its importance Name Institution Date Introduction Bluetongue, a disease caused by bluetongue virus, affects mostly ruminant livestock such as goats, sheep, cattle, deer and camelids. Bluetongue virus can cause serious systematic disorder with mild to high mortality. It is a prototype virus of orbivirus in reoviridae family. Bluetongue virus is mainly transmitted by certain types of biting midges. The disease caused by bluetongue virus can be characterized by changes in mucous lining of the mouth and nose and the foot’s coronary band. It does not affect human beings, horses and pigs. Bluetongue virus is broadly distributed throughout the temperate, subtropical and tropical regions in the world. The virus can be spread anywhere as long as midges are present. It is therefore commonly found in U.S, Australia, Africa, Mexico and china (Roth, 2008). Bluetongue virus greatly impacts livestock health particularly the domesticated animals. This paper therefore looks at the impact of bluetongue virus on domesticated animals and its importance. Impact of bluetongue virus on domesticated animals Bluetongue virus has crucial effect on a country’s domestic animals economy. The virus can spread very fast and considerably impact the health of domesticated animals. Bluetongue, a disease caused by bluetongue virus, can increase mortality and morbidity rate of domesticated animals, thus resulting into catastrophic loss in the population of sheep, goats and cows. These animals can also loose weight and reduce milk production if affected by the virus (Steinfeld & Mooney, 2010). The impact of bluetongue virus was observed in Italy and Germany when more than 250, 000 sheep and goats were infected by the virus and 48,000 goats and sheep died due to viral infection. Cattles, when infected by bluetongue virus, may display mild signs that may not even be recognized. A few days after being bitten by infected midge, cattle may become vireamic and its temperature shoots up. Some of the infected cattle can acquire ulcers. Reddening of the mouth and nose can be observed among the infected cattle. Cattles infected by bluetongue virus can become lame and their teats invaded by dermatitis (Hay, 2006). Hay (2006) claims that Bluetongue virus has a serious effect, particularly on pregnant cows. It normally affects the unborn calf even if the infected pregnant cow overcomes the infection and recovers. The virus normally crosses the placenta of infected pregnant cow into the unborn calf, thus causing the calf to be born with the virus (Capinera, 2008). The infected calf, after being born, will continuously posses the virus and remains a carrier for life. This occurs because calves do not always have mature immune system at infection time. It therefore implies that even though the infected pregnant cows can be cured, they will keep on producing infected calves that are carriers forever. Infected pregnant cow therefore usually experiences reproductive disorders that incorporate abortions, stillbirths and congenital anomalies in new born calves (Baylis & Mellor, 2008). Bluetongue virus does not only affect the unborn calf but also affects the cow’s milk production. Apart from the cow becoming ill during the viral infection, its milk production can drop significantly. The growth and fertility of the beef cows can be reduced significantly due to the infection. The heard therefore can become a major source of bluetongue virus to midges, thus causing the disease to spread very fast to other domesticated animals. Cows infected by bluetongue virus normally display mild or unapparent illness and in the process adult animals can become very ill and die (Mullen & Mullen, 2009). Maclachlan & Dubovi (2010) argues that Bluetongue virus causes serious illness in sheep. The virus normally causes sheep to experience depression, high temperatures, rapid breathing, salivation and nasal discharge. The effect of the virus can grow into a thicker nasal discharge that can crust around the sheep’s nose. The virus can also redden the lips, ears and tongue of the sheep. Domestic animals such as sheep affected by bluetongue virus can become lame. The lips, mouth, eyelids and nasal linings of the sheep normally become red and swells due to the fact that bluetongue virus mainly affects small blood vessels. Lameness normally occurs due to laminitis and inflammation of coronary band and an essential sign is a dark red to purple band within the skin and above the coronet (Maclachlan & Dubovi, 2010). Emaciation and weakness can be observed within the infected flock thus causing the animal to die after approximately six days from the day the sign was observed. The high temperature experienced by sheep can cause wool to break, thus adding to production losses. Ewes that are pregnant will always abort and remain infertile due to viral infection. The viral infection can also cause many sheep to die. Ill sheep are normally treated through supportive therapy since there is no particular treatment for bluetongue (Ashford, 2001). Cured sheep normally remain unproductive for some period after which they regain their fertility but at a reduce rate. Bluetongue virus infection in sheep is very disastrous. Mortality rate of affected sheep flocks in the continent have grown up to approximately 40%. The ones that survive lose condition normally remain sick for sometimes and become infertile (Aitken, 2007). Though some infected domestic animals may look normal at necropsy, most of them can have hemorrhage in several organs, mostly the heart. The viral infection can cause petechial and ecchymotic hemorrhages to occur on the hard palate, under the tongue, esophagus, lymph nodes, fore stomach, bladder and spleen. Erosions and ulcers can be observed anywhere around the oral cavity (Capinera, 2005). The viral infection can cause domestic animals to experience gelatinous subcutaneous edema of the neck, head, trunk and forelimbs. Bluetongue virus can cause animals such as sheep to have fragile wool and diarrhea (Suárez, 2002). Goats are domestic animals that are also vulnerable to bluetongue virus. These animals when infected by bluetongue virus normally display mild signs of fever and then recover. Goats usually remain infectious to biting midges for some weeks, thus acting as a reservoir of infection (Spickler & Roth, 2008). Goats not only display mild signs but also severe signs. Many infected goats have been observed displaying severe signs of infection, incorporating similar signs of infected sheep such as inflamed mouth, nose and skin. The virus can cause some goats to be seriously ill and even resulting into their death (Smith & Sherman, 2009). Importance of bluetongue virus Bluetongue virus causes a disease that is economically essential in several parts of the globe, including developed and developing nations. Live virus vaccines are not usually allowed since the bluetongue, a disease caused by bluetongue virus, is a vector-borne infection and always transmitted from infected ruminant animals to healthy ones by blood feeding insect biting midges (Patton, 2008). The Baculovirus expression vectors’ flexibility and the capability of baculovirus genome to accommodate huge amounts of strange DNA permit system exploitation for simultaneous expression of several bluetongue virus genes by one recombinant virus (Rushton, 2009). By referring to the 3D data structure, the recombinant virus can be arranged so as to express the two important proteins, VP3 and VP7 or the four structural proteins, VP3 and VP7 plus VP2 and VP5. VP3 and VP7 can provide CLPS that resembles the cores arranged from bluetongue virions in size and appearance. The simultaneous expression of four proteins can also result in assembly of nearly homogenous double capsid particles (Sobrino, 2008). The analysis of 3D structure of CLPS and VLPS by Cro-EM depicts that the particles types are comparable to genuine cores and virions and displays important features that are quite similar. The synthesized VLPS can also be characterized at biological and immunological levels. It has been proved that VLPs display high haemagglutination activity’s levels that are similar to genuine bluetongue virus types. The authenticity of bluetongue virus can therefore be displayed by raising antibodies further so as to express the particles that have high titres of neutralizing activity against homologous bluetongue virus serotype (Quinn & Markey, 2011). Bluetongue virus is essential since it does not affect human beings and other non-ruminant animals such as pigs, horses and dogs. The virus therefore does not risk the life of human beings. The virus outbreak cannot restrict dog walking or horse riding. Bluetongue cannot result to closure of foot paths. Human are free to move from one region to another, thus easing personal imports or exports. The disease caused by bluetongue virus can be noticed very easily, thus controlling the spread of the virus is very easy (Strauss & Strauss, 2008). Conclusion From the discussion, it is clear that bluetongue virus greatly impact domesticated animals such as cattle, sheep and goats. Bluetongue virus causes domesticated animals to become sick thus increasing their mortality and morbidity rate. High mortality and morbidity rate result into catastrophic loss in the population of sheep, goats and cows. The virus can cause Reddening of the mouth and nose among the infected cattle. Cattles infected by bluetongue virus can become lame and their teats invaded by dermatitis. Bluetongue virus has an effect on pregnant cows. Bluetongue virus causes serious illness in sheep. The virus normally causes sheep to experience depression, high temperatures, rapid breathing, salivation and nasal discharge. Goats, when infected by bluetongue virus normally display mild signs of fever and then recover, though they sometimes display severe signs. Bluetongue virus is economically important. It is also important since it does not affect human beings and other non-ruminant animals such as pigs, horses and dogs. References Strauss J., & Strauss E. (2008). Viruses and human disease. 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