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Disease is worldwide in distribution

Etiology

Pasteurella multocida, a gram negative non spore forming, non motile rods which stain bipolar.

Epizootiology

Most species of birds are infected. Turkeys are more susceptible than chickens, and older chickens are more vulnerable than young chickens. Geese and ducks of all ages are highly susceptible to fowl cholera. Survivors of fowl cholera outbreaks become carriers and are the reservoir of infection. P. multocida isolates of pigs are pathogenic to fowls. Spread of P. multocida in a flock is by feed and water contaminated with excretions. Crates, feed bags and utensils serve as a mechanical carrier of the organism.

(New duck disease, Duck septicemia, Anatipestifer syndrome, Infectious Serositis, the disease in goose is called “goose influenza”)

Etiology

The disease was first described in ducks from 3 farms in Long Island, N.Y. in 1932. R. anatipestifer (Pasteurella anatipestifer) is a gram negative, non- motile, non-spore-forming rod occurring singly, in pairs and occasionally in chains. To date, 19 serotypes are reported.

Natural and experimental hosts: primarily a disease of domestic ducks. Outbreaks also reported in turkeys. Bacteria have been isolated from pheasants, chickens, guinea fowl, quail, partridge and other waterfowl.

Etiology

Erysipelothrix rhusiopathiae.

Disease Occurrence

The disease is worldwide in distribution.

Host Range

Outbreaks of significant economic loss are in turkeys. Occasional outbreaks have been reported in pheasants, ducks, geese, guinea fowl, chukars, grebes and emus. Erysipelas also occurs in swine, sheep, sea mammals, fish and many wild animals. In humans (fish handlers, butchers, kitchen workers, turkeygrowers and veterinarians) it causes a localised inflammation called “erysipeloid”.

Etiology

Yersinia pseudotuberculosis, non-motile at 37 C but motile at room temperature around 25 C. It is a disease of turkeys, ducks, geese, chickens, guinea fowl, and companion birds and free flying birds. It has also been reported in many species of mammals including man. In man, it causes symptoms of appendicitis. The disease has been reported in many countries. Body excretions of diseased birds or mammals that contaminate soil, food and water are the important factor in the transmission of the disease. The disease usually occurs as an acute septicemia of short duration, followed by a chronic focal infection.

Etiology

There are 18 species in genus Campylobacter. Campylobacter species in poultry include C. jejuni, C. coli and C. lari. The most predominant species is C. jejuni.

Epizootiology

The infection has been reported in chicken, but the organisms have been isolated from ducks, turkeys, black birds, sparrow and pigeons.

Transmission

Possibly through faeces, as organisms are in the intestinal tract. Egg transmission of bacteria on or in the egg through hatchery is strongly suggested.

Causative Organism: Borrelia anserina

B. anserina and B. burgdorferi (borreliosis of humans) share common flagellar antigens, suggesting their close relationship. B. burgdorferi infect both mammals and birds (mallards and bobwhite quail). Geese, turkeys, chickens, ducks, pheasants and canaries are natural hosts of B. anserina. All age birds are susceptible.

Transmission

Infection is mainly transmitted by a soft tick- Argus persicus. Transmission is also by ingestion of blood, excreta or tissues from infected or dead birds, through contaminated feed or water. Use of syringe and needles on multiple birds also makes transmission possible.

Etiology

Intestinal spirochetes colonise the large intestine of avian, swine and humans.

Family spirochaetacae has six genera, of which Borrelia, Serpulina and Treponema have species pathogenic for animals. Avian intestinal spirochetes are grouped in four: Serpulina hyodysenteriae, S. intermedius, S. pilosicoli (Angullina coli) and an unnamed group.

Chicken S. hyodysenteriae is different from porcine one. S. hyodysentriae, Angullina coli and unclassified groups are present in the USA, whereas S.intermedius is in Europe and Australia.

Avian intestinal spirochetes are gram negative, stain brown with silver impregnation techniques and blue in Wright-Giemsa stain. They can be divided in 3 pathotypes 1) severely pathogenic 2) Mildly to moderate pathogenic and 3) subclinical or apathogenic.

In avian species following diseases are caused by Clostridium bacteria.

1. Ulcerative enteritis
2. Necrotic enteritis
3. Gangrenous Dermatitis
4. Botulism
5. Yolk sac infections.

Clostridia infections are not common in birds and are not a significant source of infection for man and animals.

Etiology

Avibacter paragallinarum Serotype A, B and C. Based on hemagglutinin serotyping, three serotypes (A, B and C) have been recognized.

Epizootiology

The chicken is the natural host although the disease has occasionally been diagnosed in pheasants. All ages of chicken are susceptible but birds up to 10 weeks are less vulnerable.

1. The chronic or healthy carrier birds serve as source of infection. Infection within farm occurs by contact with drinking water or feed contaminated by nasal discharge from sick/carrier chickens. To farms situated at a distance, infection is through air borne transmission.
2. The disease occurs more in cold and wet conditions. The more severe disease occurs when other respiratory diseases are prevalent at the farm.

Etiology

Ornithobacteriun rhinotracheale, bacteria, under phylum Cytophaga- Flavobacterium-Bacteroids. It is Gram negative non-motile, non-sporulating pleomorphic rod shaped bacteria. 18 serotypes Athrough R have been identified. Serotype A is prevalent in chicken and turkeys.

Disease occurrence

The disease is worldwide in distribution.

An important disease in Turkey producing areas of the world. It is reported an opportunistic pathogen to human. Bactria grows in ciliated epithelium of vertebrates.

Etiology

Bordetella avium, a small Gram-negative bacillus, which is motile and aerobic. Differences in pathogenicity among strains exist.

Transmission

Recovered birds serve as carriers. Turkey coryza is highly contagious, and transmission occurs directly through close contact and contaminated feed and water.

Etiology

Genus Mycobacterium contains many pathogenic species that can cause disease in birds (M. avium, M. tuberculosis, M. genavenes, M. gordonae). Within M. avium, organisms are divided into four sub species. M. avium sp avium, M.avium sp silvaticum, M. avium sp homnissuis and M. avium sp paratuberculosis. Mycobacterium avium sp avium - has wide host spectrum; poultry, pigeons, raptors, ratites and wild birds. M. genavense- affects Psittacines and passarines. M. tuberculosis- psittacines and other cage birds, and wild birds in captivity. M.bovis- Psittacines and others.

Under natural conditions, M. avium sp avium does not cause severe disease in mammals except in rabbit and pig. Majority of mycobacteriosis in pigs is by M. avium sp avium. In cattle and other mammal infection by M. avium remain localized and is known to give positive reaction to mammalian tuberculin. The disease in caged and wild birds in captivity is common with M. tuberculosis, because of its close contact with humans. Tuberculosis is a serious problem in zoological gardens. M. avium is being isolated in increasing number of immunocompromized human patients.

Chlamydial organisms are spherical 0.2-1.5 um in diameter. They can be stained and seen in the light microscope, but they grow only in living cells. Chlamydial organisms infect mammals and birds causing various disease syndromes. Chlamydiacae family has one genus; Chlamydia. C. trachomatis, C. suis and C. muridarum. They cause disease in man, swine and mice. C. psittaci, C. pneumonia, C. felis, C. Caviae, and C. abortus. cause disease in man, birds and animals. Species can be differentiated on their growth characters inside the host cell.

Etiology

Mostly associated with bacterial infections. Salmonella sp, Escherichia coli, streptococcus fecalis, Staphylococcus aureus, Clostridia sp. (C. pefringens), Pseudomonas and Proteus spp. have been isolated from cases of omphalitis. Chilling, overheating or stress during transport may predispose for the condition.

Inflammation of yolk sac, characterized by infected unhealed navels in young birds.

The diseases caused by Staphylococci are found in all avian species and reported through out the world.

Etiology

There are more than 45 species and 25 subspecies in the genus Staphylococcus.

S. aureus is the most common species of birds causing disease. Staphylococci are Gram - positive, coccoid and when grown on solid medium, bacteria form grape like clusters.

Streptococcosis has been reported from avian species worldwide. Bacteria produce acute septicemic and chronic infection. Streptococcosis has wide range of host ranging from many avian species including wild birds.

Etiology

Streptococci are Gram-positive, non-spore forming, non-motile facultative anaerobes. They occur singly, in pairs or short chains. S. zoozooepidemicus is species associated with disease in avian species. Other species of streptococcus (S. bovis, S. dysgalactiae, S. pleomorphus) have occasionally been isolated from birds.

Enterococcus sp. belongs to Lancefield antigenic serogroup D. Enterococcus is considered normal flora of the chicken intestine.

Etiology

Enterococci bacteria are Gram positive, spherical seen in singles, pairs or chain. Enterococuus sp. Causing disease in birds include E. faecalis, E. faecium, E. durans, E. avium, E. hirae and E. cecorum. E. faecalis is most common isolate from birds.

ND is a viral disease of poultry, wild and cage birds characterized by marked variation in morbidity, mortality, signs and lesions. Reported in 235 species of birds.

A disease of primary importance and concern worldwide which causes continuous massive economic loss. It is a reportable disease in many countries of the world.

Occurrence

Species: All birds susceptible. Temporary conjunctivitis may develop in people who come in close contact with NDV for the first time.

Etiology

The subfamily Pneumovirinae includes two genera: Pneumoviruses and metapneumovirus. The later consists of both human and avian metapneumovirus (aMPV). aMPV produces turkey rhinotracheitis (TRT) in turkey and Swollen head syndrome (SHS) in chickens. aMPV has been detected in other species of birds, but the disease in those birds are not well defined.

Occurrence Species

A new disease of turkeys (in the UK since 1985) which is suspected to cause some lesser problems in chickens.

ILT is an acute viral disease of chickens, pheasants and peafowl characterized by marked dyspnea, coughing, gasping and expectoration of bloody exudate. The disease is worldwide.

Hosts

Chickens particularly susceptible; reported to occur in pheasants and peafowl.

Age Range

All ages susceptible but is most often found in adult (mature or nearly mature) commercial chicken layers.

IB is an acute, highly contagious, viral disease of chickens characterized by respiratory signs (gasping, sneezing, coughing, and nasal discharge), the severe renal disease associated with neurotropic strains, and a marked decrease in egg production. It is a serious cause of sub-optimal egg production and poor egg quality. This disease is worldwide in ditribution.

Hosts

Chickens only. Recently IBV has been detected in species other than chickens. The disease may be produced only in chickens, IBV may multiply in other species of birds and be a source of infection.

Etiology

IB is caused by the avian coronavirus; numerous strains of infectious bronchitis virus (IBV) exist because of high genetic diversity and cross protection between strains is not reliable.

This ‘virus’ is widespread in commercial flocks worldwide, but its taxonomic position is not determined. The disease is characterized by aplastic anaemia and generalized lymphoid atrophy with a concomitant immunosuppression. Consequently, infectious anaemia is frequently complicated by viral, bacterial, or fungal infections.

Occurrence

Chickens up to 3 weeks of age are most susceptible.

Adenoviruses have been found in several species of birds and animals. There are at least 12 serotypes of chicken adenoviruses. The chicken adenoviruses are host specific, meaning they will not infect other animal species. Avian adenoviruses are divided into three major groups. Members of each type may share group antigens, but there is no common antigen shared between types.

Quail bronchitis (QB) is caused by group I (aviadenovirus). QB is an acute respiratory disease of bobwhite quail, occasionally with high mortality. Disease has sporadic occurrence many parts of the world. QB virus is closely related to the prototype CELO (chick embryo lethal orphan) virus, which is cause of high mortality in chicks.

IBH is an adenovirus infection of young chickens characterized by sudden onset and sharply increased mortality, short course, anaemia, and hepatitis often accompanied by intranuclear inclusion bodies. It is described in Canada, USA and many other countries.

Etiology

Group 1 adenovirus. First reported in Pakistan in 1987, where it caused a devastating effect on broiler industry. It has spread to all continents.

EDS 76 is an infectious disease of laying hens caused by hemagglutinating adenovirus and characterized by failure to achieve production targets or by the production of thin-shelled or shell-less eggs in otherwise healthy birds.

This important disease caused loss of egg production for several years - vaccination introduced the disease and a new vaccine virtually eradicated it.

(Tenosynovitis; Ruptured gastrocnemius tendon; Reovirus infection)

Viral arthritis is a reovirus infection primarily of broilers characterized by arthritis and tenosynovitis (primarily of the tarsus and metatarsus, the digital flexor and tarsometatarsal extensor tendons) and, occasionally, by rupture of the gastrocnemius tendon(s) resulting in lameness and condemnations at slaughter. The disease is reported worldwide.

Fowl pox is a slow spreading viral disease of chickens, turkeys and other birds characterized by cutaneous lesions on the un-feathered skin of the head, neck, legs and feet and/or by diphtheritic lesions in the upper digestive and respiratory tract. The disease is worldwide in distribution.

Occurrence

Among poultry chicken and turkey are more susceptible. Other birds include pigeons, canaries, psittacines and wild birds. Fowl pox has been reported from more than 200 species of birds. The incidence is severe in multiple age groups and intensive poultry farming areas.

IBD is an acute, contagious, viral disease of young chickens characterized by diarrhoea, vent pecking, trembling, incoordination, inflammation followed by atrophy of the bursa of Fabricius (BF) and by a variable degree of immunosuppression.

In the USA the disease was reported in Gumboro, Delaware in 1962, hence the name. The occurrence is worldwide.

Marek’s disease is a herpesvirus-induced neoplastic disease of chickens characterized by infiltration of various nerve trunks and/or organs with pleomorphic lymphoid cells. Marek’s disease is world wide in distribution. Marek’s Disease has been named after Josef Marek who published the disease in 4 roosters in 1907.

Occurrence

In chickens only, however turkeys and quail have limited susceptibility. Lesions similar to MD have been seen in pheasants, ducks, pigeons, geese, canaries, budgerigars, swans and great horned owls. However, aetiology for lesions in these species has not been proved. It may appear at 3-4 weeks but usually after eight weeks, with major losses from 12-25 weeks. Morbidity and mortality varies depending on the virulence of MDV.

LL is a retrovirus-causes, neoplastic disease of semi-mature or mature chickens characterized by a gradual onset in a flock, persistent low mortality and neoplasia of, the bursa of Fabricius (BF) with metastasis to many other internal organs especially the liver, spleen and kidney.

The neoplastic disease primarily of broiler breeders and broilers causing serious economic losses in the commercial poultry industry. A case has been recorded in a budgerigar.

Etiology

ALV-J subgroup, identified in 1988. It became widespread in commercial meat type poultry in the 1990’s. Transmission of ALV-J is much higher than other subgroups thus making control much more difficult.

Term endotheliosis designates a variety of syndrome caused by a reticuloendothelial virus (REV). REV caused syndromes have been demonstrated world wide.

Etiology

Based on replication of the virus in chicken fibroblast cell culture, two strains are known: replication defective T strain and the non-defective A strain. The REV manifests three distinct diseases syndromes:

Etiology

Avian Nephritis Virus (ANV), an RNA virus is Astro virus under the genus Avastrovirus in Astroviridae family. Strains of ANV exist. ANV is very resistant and stable in the environment.

AI is a viral disease affecting the respiratory, enteric or nervous system of many kinds of birds. The most virulent form is an acute, generalized disease characterized in poultry by a short course and extremely high mortality.

(AE; Epidemic Tremor; Infectious Avian Encephalomyelitis)

AE is a viral infection of chickens, turkeys, pheasants and cortunix quail characterized in young birds by ataxia progressing to paralysis and, usually, by tremors of the head and neck. Infected adults usually show no signs. AE is world wide in distribution.

Etiology

A turkey coronavirus (TCV).

Hosts

Turkeys of all ages, but the disease is mostly observed in young turkeys (first few weeks old).

It is an acute disease of turkeys, occurring in 6-7 wk. -Old turkeys, but has been seen in younger and older turkeys as well. The disease is worldwide in distribution.

Etiological Agent

It belongs to adenovirus type II. A serologically indistinguishable virus from HE virus, causes marble spleen disease (MSD) in confinement reared pheasants (3-8 months old). The disease shows predominantly respiratory signs. A virus of the same group causes avian adenovirus group II splenomegaly (AAS) in chickens.

Etiology Herpes Virus

Variation in pathogenicity of virus strains has been reported, but all strains appear identical immunologically.

Occurrence

The disease was first reported in the Netherlands in 1923. The disease has been confirmed in France, Belgium, Canada, India, Thailand, England, Hungary, Austria, Denmark and Vietnam, and suspected in China.

DVH is a highly fatal infection of young ducklings. Lesions are primarily in the liver.

It is an acute disease of pheasants, chukars, partridges, turkeys, ducks, pigeons and wild birds. The viruses of EEE and WEE are of public health importance as they infect humans and occasionally cause fatal disease. The disease is further significant because of its link to disease in horses.

Etiology

The arboviruses are grouped into 12 different families. The five arboviruses causing disease in birds are Eastern equine encephalitis (EEE) virus, Western equine encephalitis (WEE) virus, Highland J (HJ) virus, Israel turkey meningoencephalitis (IT) virus and West Nile Virus WNV. The first three are in Togaviridae, and IT and West Nile Virus (WNV) are in Flaviviridae.

WNV was first identified in the West Nile district of Uganda in 1937. Reported in Western Hemisphere for the first time in 1999, in New York City. The virus had until that time been found only in Africa, Eastern Europe, West Asia and the Middle East.

Introduction

This is a disease mainly of the respiratory system affecting domestic poultry, wild birds and zoo birds. Systemic aspergillosis affecting visceral organs and other tissues of the bird’s body is also reported. Reports are also available on eye and brain infections.

Introduction

1. Serious outbreaks of thrush have been observed in chickens, pigeons, geese, turkeys, pheasants, quail, peacock and many other species of birds.
2. Candida albicans is the most commonly isolated fungus from the outbreak. Mucor spp. and Aspergilli were also found in some cases.
3. The outbreaks are associated with unhygienic conditions and nutritional deficiencies. Infection is more common in young birds up to 10 weeks of age. Morbidity is very high and mortality ranges from 10-75%. Clinical signs are not specific. Poor growth and ruffled feathers are only clinical signs.

Etiology

Cryptococcosis (KRIP-toe-cock-co-sis) is caused by the fungus, Cryptococcus neoformans (KRIP-toe-cock-kus knee-O-for-mans). It is found worldwide and primarily affects cats and people with weak immune systems.

It is a fungal infection of skin and the term favus is used for the disease in poultry. The disease is world wide in distribution.

Etiology

Microsporum gallinae, a fungus. The fungus is zoonotic. Lesions of ring worm are produced in humans in contact with infected birds.

Diseases caused by toxic metabolites of fungi are called mycotoxicosis. It affects man and animals including birds. Fungi which grow on feeds and grains in an unfavorable environment mostly cause mycotoxicosis in birds.

The disease is worldwide in distribution and remains the major parasitic problem in the poultry industry. The problems occur principally in poultry maintained on deep litter.

Etiology

Coccidiosis of all classes of poultry is caused by one or more of the many species of coccidia of Eimeria species. In chickens nine main species are encountered. Eimeria tenella, E. necatrix, E. maxima, E. acervulina, E. mitis, E. mivati, E. hagani, E. brunetti and E. preacox.

Cryptosporidiosis is a protozoan disease.

Species

1. C. meleagridis: Infects small intestine.
2. C. baileyi: Infects digestive tract (bursa of Fabricius and cloaca), kidneys and respiratory tract.