Infectious bursal disease (IBD), also known as Gumboro disease, infectious bursitis and infectious avian nephrosis, is a highly contagious disease of young chickens and turkeys caused by infectious bursal disease virus (IBDV), characterized by immunosuppression and mortality generally at 3 to 6 weeks of age. The disease was first discovered in Gumboro, Delaware in 1962. It is economically important to the poultry industry worldwide due to increased susceptibility to other diseases and negative interference with effective vaccination. In recent years, very virulent strains of IBDV (vvIBDV), causing severe mortality in chicken, have emerged in Europe, Latin America, South-East Asia, Africa and the Middle East. Infection is via the oro-fecal route, with affected bird excreting high levels of the virus for approximately 2 weeks after infection. The disease is easily spread from infected chickens to healthy chickens through food, water, and physical contact.
Avian infectious bronchitis (IB) is an acute and highly contagious respiratory disease of chickens. The disease is caused by avian infectious bronchitis virus (IBV), a coronavirus, and characterized by respiratory signs including gasping, coughing, sneezing, tracheal rales, and nasal discharge. In young chickens, severe respiratory distress may occur. In layers, respiratory distress, nephritis, decrease in egg production, and loss of internal and external egg quality are reported.
Marek's disease is a highly contagious viral neoplastic disease in chickens. It is named after József Marek, a Hungarian veterinarian. Marek's disease is caused by an alphaherpesvirus known as 'Marek's disease virus' (MDV) or Gallid alphaherpesvirus 2 (GaHV-2). The disease is characterized by the presence of T cell lymphoma as well as infiltration of nerves and organs by lymphocytes. Viruses related to MDV appear to be benign and can be used as vaccine strains to prevent Marek's disease. For example, the related herpesvirus found in turkeys (HVT), causes no apparent disease in the birds, and continues to be used as a vaccine strain for prevention of Marek's disease.
Chicken anemia virus, or CAV, is currently a member of the Anelloviridae family which is found worldwide. The virus only affects chickens. CAV is a non-enveloped icosahedral single stranded DNA virus, which causes bone marrow atrophy, anemia, and severe immunosuppression. Clinical signs of CAV infection are predominantly found in young chicks due to vertical transmission from the breeder hens whose maternal antibodies have not yet formed following exposure. Clinical disease is rare today because of the widespread practice of vaccinating breeders, but the subclinical form of the disease—which normally affects birds more than two weeks of age following horizontal transmission of the virus via the fecal-oral route—is ubiquitous. The virus is very resistant in the environment, making elimination very difficult.
Aviadenoviruses are adenoviruses that affect birds—particularly chickens, ducks, geese, turkeys and pheasants. There are 15 species in this genus. Viruses in this genus cause specific disease syndromes such as Quail Bronchitis (QB), Egg Drop Syndrome (EDS), Haemorrhagic Enteritis (HE), Pheasant Marble Spleen Disease (MSD), and Inclusion Body Hepatitis (IBH). Avian adenoviruses have a worldwide distribution and it is common to find multiple species on a single farm. The most common serogroups are serogroup 1, 2 and 3.
Proventricular dilatation disease (PDD) is an incurable probably viral disease of psittacine birds. It was first recognized and described in 1978 by Dr. Hannis L. Stoddard. Since the first reported cases were involving species of macaw, the condition was termed macaw wasting syndrome.
Mycoplasma gallisepticum (MG) is a bacterium belonging to the class Mollicutes and the family Mycoplasmataceae. It is the causative agent of chronic respiratory disease (CRD) in chickens and infectious sinusitis in turkeys, chickens, game birds, pigeons, and passerine birds of all ages.
Tremovirus, also known epidemic tremor, is a virus genus belonging to the Picornaviridae family. The genus has two species, Tremovirus A, which is also called Avian encephalomyelitis virus, and Tremovirus B. The first avian picornavirus to have its genome sequenced, it causes epidemic tremor in chickens.
Avian orthoreovirus, also known as avian reovirus, is an orthoreovirus from the Reoviridae family. Infection causes arthritis and tenosynovitis in poultry. It can also cause respiratory disease.
Bovine Adenovirus, also known as BAdV, is a member of the Adenoviridae family that causes disease in cattle. There are 10 serotypes recognised and the virus had a worldwide distribution—being particularly common in Africa and Central America.
Bovine coronavirus is a coronavirus which is a member of the species Betacoronavirus 1. The infecting virus is an enveloped, positive-sense, single-stranded RNA virus which enters its host cell by binding to the N-acetyl-9-O-acetylneuraminic acid recepter. Infection causes calf enteritis and contributes to the enzootic pneumonia complex in calves. It can also cause winter dysentery in adult cattle. It can infect both domestic and wild ruminants and has a worldwide distribution. Transmission is horizontal, via oro-fecal or respiratory routes. Like other coronaviruses from genus Betacoronavirus, subgenus Embecovirus, it has a surface protein called hemagglutinin esterase (HE) in addition to the four structural proteins shared by all coronaviruses.
Bovine gammaherpesvirus 4 (BoHV-4) is a member of the Herpesviridae family. It is part of the subfamily Gammaherpesvirinae and genus Rhadinovirus. Infection is normally sub-clinical but can cause reproductive disease in cattle such as endometritis, vulvovaginitis and mastitis. Transmission is both vertical and horizontal. It can also be indirectly spread by fomites. Distribution is worldwide and the virus infects a range of ruminants, including bison, buffalo, sheep and goats.
Porcine adenovirus is a virus in the family Adenoviridae. It causes mild gastrointestinal diseases in pigs and is thought to contribute to multifactorial porcine respiratory diseases complexes. Several strains of the virus can be found worldwide, and transmission occurs horizontally by the fecal-oral route.
Porcine intestinal spirochaetosis is a notifiable pig disease caused by certain spirochetal bacteria (Brachyspira hyodysenteriae and Brachyspira pilosicoli. Infection causes mild gastrointestinal signs in young pigs and can also be transmitted as intestinal spirochetosis in humans, as it is a zoonosis.
Porcine enzootic pneumonia, also known as mycoplasmal pneumonia, is a chronic respiratory disease of pigs caused by Mycoplasma hyopneumoniae.
Porcine epidemic diarrhea is a condition caused by the porcine epidemic diarrhea virus that leads to severe gastrointestinal disease in pigs.
Derzsy's disease is caused by Anseriform dependoparvovirus 1, in the Parvoviridae family. It affects geese and Muscovy ducks.
Egg drop syndrome '76 is one of the important viral diseases of birds, notably chickens, ducks, geese and swans. It is characterised by a sudden drop in production of eggs as well as its eggshell quality in apparent healthy laying birds.
Infectious coryza is a serious bacterial disease of chickens which affects respiratory system and it is manifested by inflammation of the area below the eye, nasal discharge and sneezing. The disease is found all over the world causing high economic losses. Economic loss is due to stumping off and reduction of egg production in case of laying chickens. The disease was discovered early 1930s by considering clinical signs.
Border disease (BD) is a viral disease of sheep and goats, primarily causing congenital diseases, but can also cause acute and persistent infections. It first appeared in the border regions of England and Wales in 1959, and has since spread world-wide. Lambs that are born with BD are commonly known as 'hairy shakers' due to the primary presentation of the disease. The disease was recognized before the virus, therefore the common name of the disease predates the understanding of the viral pathology. The virus can cause a significant reduction in the percentage of surviving lambs, thus it has a large economic impact on farmers.
