Veterinary virology is the study of viruses in non-human animals. It is an important branch of

veterinary medicine Veterinary medicine is the branch of medicine that deals with the prevention, management, medical diagnosis, diagnosis, and treatment of disease, disorder, and injury in non-human animals. The scope of veterinary medicine is wide, covering all a ...

Rhabdoviruses

Rhabdoviruses are a diverse family of single stranded, negative sense RNA viruses that infect a wide range of hosts, from plants and insects, to fish and mammals. The ''Rhaboviridae'' family consists of six

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

, two of which, cytorhabdoviruses and nucleorhabdoviruses, only infect plants. Novirhabdoviruses infect fish, and vesiculovirus, lyssavirus and ephemerovirus infect mammals, fish and invertebrates. The family includes pathogens such as

rabies Rabies is a viral disease that causes encephalitis in humans and other mammals. It was historically referred to as hydrophobia ("fear of water") because its victims panic when offered liquids to drink. Early symptoms can include fever and abn ...

virus, vesicular stomatitis virus and potato yellow dwarf virus that are of public health, veterinary, and agricultural significance.

Foot-and-mouth disease virus

Foot-and-mouth disease virus (FMDV) is a member of the Aphthovirus genus in the Picornaviridae family and is the cause of

foot-and-mouth disease Foot-and-mouth disease (FMD) or hoof-and-mouth disease (HMD) is an infectious disease, infectious and sometimes fatal virus (biology), viral disease that primarily affects even-toed ungulates, including domestic and wild Bovidae, bovids. The vir ...

in pigs, cattle, sheep and goats. It is a non-enveloped, positive strand, RNA virus. FMDV is a highly contagious virus. It enters the body through inhalation.

Pestiviruses

Pestiviruses have a single stranded, positive-sense RNA genomes. They cause Classical swine fever (CSF) and Bovine viral diarrhea(BVD). Mucosal disease is a distinct, chronic persistent infection, whereas BVD is an acute infection.

Arteriviruses

Arteriviruses are small, enveloped, animal viruses with an icosahedral core containing a positive-sense

RNA Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA). RNA and deoxyrib ...

genome. The family includes equine arteritis virus (EAV), porcine reproductive and respiratory syndrome virus (PRRSV), lactate dehydrogenase elevating virus (LDV) of mice and simian haemorrhagic fever virus (SHFV).

Coronaviruses

Coronavirus Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the comm ...

es are enveloped viruses with a positive-sense RNA genome and with a nucleocapsid of helical symmetry. They infect the upper respiratory and gastrointestinal tract of mammals and birds. They are the cause of a wide range of diseases in cats, dog, pigs, rodents, cattle and humans. Transmission is by the faecal-oral route.

Toroviruses

Torovirus is a genus of viruses within the family '' Coronaviridae'', subfamily ''Torovirinae'' that primarily infect

vertebrates Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

and include Berne virus of horses and Breda virus of cattle. They cause

gastroenteritis Gastroenteritis, also known as infectious diarrhea, is an inflammation of the Human gastrointestinal tract, gastrointestinal tract including the stomach and intestine. Symptoms may include diarrhea, vomiting, and abdominal pain. Fever, lack of ...

in mammals, including humans but rarely.

Influenza

Influenza Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These sympto ...

is caused by RNA viruses of the family Orthomyxoviridae and affects birds and mammals.

Avian influenza

Wild aquatic birds are the natural hosts for a large variety of

influenza Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These sympto ...

A viruses. Occasionally viruses are transmitted from this reservoir to other species and may then cause devastating outbreaks in domestic poultry or give rise to human influenza

pandemic A pandemic ( ) is an epidemic of an infectious disease that has a sudden increase in cases and spreads across a large region, for instance multiple continents or worldwide, affecting a substantial number of individuals. Widespread endemic (epi ...

Swine influenza

Bluetongue virus

Bluetongue virus (BTV), a member of Orbivirus genus within the

Reoviridae ''Reovirales'' is an order of double-stranded RNA viruses. Member viruses, called reoviruses, have a wide host range, including vertebrates, invertebrates, plants, protists and fungi. They lack lipid envelopes and package their segmented geno ...

family causes serious disease in livestock (sheep, goat, cattle). It is non-enveloped, double-stranded RNA virus. The genome is segmented.

Circoviruses

Circovirus ''Circovirus'' is a genus of viruses, in the family ''Circoviridae''. Birds (such as pigeons and ducks) and pigs serve as natural hosts, though dogs have been shown to be infected as well. Circoviruses are single stranded DNA (ssDNA) viruses. The ...

es are small single-stranded DNA viruses. There are two genera: gyrovirus, with one species called chicken anemia virus; and circovirus, which includes porcine circovirus types 1 and 2, psittacine beak and feather disease virus, pigeon circovirus, canary circovirus, goose circovirus.

Herpesviruses

Herpesviruses are ubiquitous pathogens infecting a variety of animals, including humans. Hosts include many economically important species such as abalone, oysters, salmon, poultry ( avian infectious laryngotracheitis,

Marek's disease Marek's disease is a highly contagious viral neoplastic disease in chickens. It is named after József Marek, a Hungarian veterinarian who described it in 1907. Marek's disease is caused by an alphaherpesvirus commonly known as "Marek's disea ...

), cattle ( bovine malignant catarrhal fever), dogs, goats, horses, cats ( feline viral rhinotracheitis), and pigs ( pseudorabies). Infections may be severe and may result in fatalities or reduced productivity. Therefore, outbreaks of herpesviruses in livestock cause significant financial losses and are an important area of study in veterinary virology.

African swine fever virus

African swine fever virus African swine fever virus (ASFV) is a large, double-stranded DNA virus in the ''Asfarviridae'' family. It is the causative agent of African swine fever (ASF). The virus causes a haemorrhagic fever, hemorrhagic fever with high mortality rates i ...

(ASFV) is a large double-stranded

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

virus which replicates in the

cytoplasm The cytoplasm describes all the material within a eukaryotic or prokaryotic cell, enclosed by the cell membrane, including the organelles and excluding the nucleus in eukaryotic cells. The material inside the nucleus of a eukaryotic cell a ...

of infected cells and is the only member of the Asfarviridae family. The virus causes a lethal haemorraghic disease in domestic pigs. Some strains can cause death of animals within as little as a week after infection. In other species, the virus causes no obvious disease. ASFV is endemic to

sub-Saharan Africa Sub-Saharan Africa is the area and regions of the continent of Africa that lie south of the Sahara. These include Central Africa, East Africa, Southern Africa, and West Africa. Geopolitically, in addition to the list of sovereign states and ...

and exists in the wild through a cycle of infection between ticks and wild pigs, bushpigs and warthogs.

Retroviruses

Retrovirus A retrovirus is a type of virus that inserts a DNA copy of its RNA genome into the DNA of a host cell that it invades, thus changing the genome of that cell. After invading a host cell's cytoplasm, the virus uses its own reverse transcriptase e ...

es are established pathogens of veterinary importance. They are generally a cause of cancer or immune deficiency.

Flaviviruses

Flaviviruses constitute a family of linear, single-stranded RNA(+) viruses. Flaviviruses include the

West Nile virus West Nile virus (WNV) is a single-stranded RNA virus that causes West Nile fever. It is a member of the family ''Flaviviridae'', from the genus ''Flavivirus'', which also contains the Zika virus, dengue virus, and yellow fever virus. The virus ...

, dengue virus, Tick-borne Encephalitis Virus, Yellow Fever Virus, and several other viruses. Many flavivirus species can replicate in both mammalian and insect cells. Most flaviviruses are

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

borne and multiply in both vertebrates and arthropods. The viruses in this family that are of veterinary importance include Japanese encephalitis virus, St. Louis encephalitis virus,

, Israel turkey meningoencephalomyelitis virus, Sitiawan virus, Wesselsbron virus, yellow fever virus and the tick-borne flaviviruses e.g. louping ill virus.

Paramyxoviruses

Paramyxoviruses are a diverse family of non-segmented negative strand RNA viruses that include many highly pathogenic viruses affecting humans, animals, and birds. These include canine distemper virus ( dogs), phocine distemper virus ( seals), cetacean morbillivirus (

dolphin A dolphin is an aquatic mammal in the cetacean clade Odontoceti (toothed whale). Dolphins belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontopori ...

s and

porpoise Porpoises () are small Oceanic dolphin, dolphin-like cetaceans classified under the family Phocoenidae. Although similar in appearance to dolphins, they are more closely related to narwhals and Beluga whale, belugas than to the Oceanic dolphi ...

Newcastle disease virus Newcastle usually refers to: *Newcastle upon Tyne, a city and metropolitan borough in Tyne and Wear, England, United Kingdom *Newcastle-under-Lyme, a town in Staffordshire, England, United Kingdom *Newcastle, New South Wales, a metropolitan area ...

(

birds Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

) and

rinderpest virus Rinderpest (also cattle plague or steppe murrain) was an infectious viral disease of cattle, domestic water buffalo, and many other species of even-toed ungulates, including gaurs, buffaloes, large antelope, deer, giraffes, wildebeests, and ...

(

cattle Cattle (''Bos taurus'') are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus '' Bos''. Mature female cattle are calle ...

). Some paramyxoviruses such as the

henipavirus ''Henipavirus'' is a genus of negative-strand RNA viruses in the family ''Paramyxoviridae'', order ''Mononegavirales'' containing five established species, and numerous others still under study. Henipaviruses are naturally harboured by several s ...

es are

zoonotic A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a virus, bacterium, parasite, fungi, or prion) that can jump from a non-human vertebrate to a human. When h ...

pathogens, occurring primarily in an animal hosts, but also able to infect humans.

Parvovirus

Parvovirus Parvoviruses are a family of animal viruses that constitute the family ''Parvoviridae''. They have linear, single-stranded DNA (ssDNA) genomes that typically contain two genes encoding for a replication initiator protein, called NS1, and the p ...

es are linear, non-segmented single-stranded

DNA virus A DNA virus is a virus that has a genome made of deoxyribonucleic acid (DNA) that is replicated by a DNA polymerase. They can be divided between those that have two strands of DNA in their genome, called double-stranded DNA (dsDNA) viruses, and t ...

es, with an average genome size of 5000 nucleotides. They are classified as group II viruses in

Baltimore classification Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a disti ...

of viruses. Parvoviruses are among the smallest viruses (hence the name, from

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

''parvus'' meaning ''small'') and are 18–28 nm in diameter. Parvoviruses can cause

disease A disease is a particular abnormal condition that adversely affects the structure or function (biology), function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical condi ...

in some

animal Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, ...

s, including

starfish Starfish or sea stars are Star polygon, star-shaped echinoderms belonging to the class (biology), class Asteroidea (). Common usage frequently finds these names being also applied to brittle star, ophiuroids, which are correctly referred to ...

and humans. Because the viruses require actively dividing cells to replicate, the type of tissue infected varies with the age of the animal. The

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...

and

lymphatic system The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphoid organs, lympha ...

can be affected at any age, leading to vomiting, diarrhea and

immunosuppression Immunosuppression is a reduction of the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse react ...

but

cerebellar hypoplasia Cerebellar hypoplasia is characterized by reduced cerebellar volume, even though cerebellar shape is (near) normal. It consists of a heterogeneous group of disorders of cerebellum, cerebellar maldevelopment presenting as early-onset Non-progress ...

is only seen in cats that were infected in the womb or at less than two weeks of age, and disease of the

myocardium Cardiac muscle (also called heart muscle or myocardium) is one of three types of vertebrate muscle tissues, the others being skeletal muscle and smooth muscle. It is an involuntary, striated muscle that constitutes the main tissue of the wall o ...

is seen in puppies infected between the ages of three and eight weeks.

References

{{reflist, 2 Molecular biology Animal viral diseases