Fowl cholera is also called avian cholera, avian pasteurellosis, avian hemorrhagic septicemia. 

It is the most common pasteurellosis

Pasteurellosis

Pasteurellosis is an infection with a species of the bacteria genus Pasteurella, which is found in humans and animals.Pasteurella multocida is carried in mouth and respiratory tract of several animals, notably cats. It is a small Gram negative bacillus with bipolar staining by Wayson stain...

 of poultry

Poultry

Poultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...

. As the causative agent is Pasteurella multocida

Pasteurella multocida

Pasteurella multocida is a Gram-negative, non-motile coccobacillus that is penicillin-sensitive and belongs to the Pasteurellaceae family . It can cause avian cholera in birds and a zoonotic infection in humans, which typically is a result of bites or scratches from domestic pets...

, it is considered as a zoonosis

Zoonosis

A zoonosis or zoonoseis any infectious disease that can be transmitted from non-human animals to humans or from humans to non-human animals . In a study of 1415 pathogens known to affect humans, 61% were zoonotic...

.

Adult birds and old chickens are more susceptible. In parental flocks, cocks are far more susceptible than hens. 

Besides chicken

Chicken

The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird...

s, the disease also concerns turkey

Turkey

Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

s, duck

Duck

Duck is the common name for a large number of species in the Anatidae family of birds, which also includes swans and geese. The ducks are divided among several subfamilies in the Anatidae family; they do not represent a monophyletic group but a form taxon, since swans and geese are not considered...

s, geese, raptor

Bird of prey

Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....

s, and canarie

Serinus

The genus Serinus is a large genus of birds in the finch family Fringillidae found mostly in the Afrotropical region with some outlying species in Europe and Asia. The genus contains several species groups including canaries, seedeaters and the African siskins...

s. Turkeys are particularly sensitive, with mortality ranging to 65 %. 

The recognition of this pathological condition is of ever increasing importance for differential diagnosis with avian influenza.

History

The disease was first recorded in the 18th century. However it was not until the 1880s that Louis Pasteur first isolated and grew it in pure culture. Originally a disease of fowl in Europe, it was first recorded in North America in 1943-44. Since then outbreaks have been recorded almost annually in wild birds. Today, this disease is most prevalent in wild waterfowl of North America.

In 2011 an outbreak of avian

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

 cholera killed thousands of eider ducks in Arctic

Arctic

The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...

 regions of Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. Scientists are studying the outbreak and its potential to spread to Greenland

Greenland

Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...

.

Epidemiology

Outbreaks occur in cold and wet weather (in late summer, fall and winter).
The outbreaks are often traced back to the presence of rodent

Rodent

Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

s in the breeding houses. These are thought to spread the disease from carcasses of dead birds (possibly from neighboring backyards), improperly disposed.
Once the disease is introduced to a flock, it will stay until culling. Chronic carriers can always lead to re-emerging of the disease in susceptible birds.

In wild birds, this disease most commonly associated with wetlands. Blanchong et al. determined that wetlands act as short term reservoirs, recording large amounts of the bacterium in the soil and water through the duration of the outbreak. Wetlands, however, are not long term reservoirs. The disease presents in two very different forms: acute and chronic. Birds with chronic avian cholera, more common in domestic fowl, exhibit prolonged illness with more localized infections. Chronic infection has been demonstrated in Snow Geese, and these individuals are believed to be long term migrating reservoirs for the disease. Once the bacteria gets introduced into a population of susceptible birds, an outbreak of acute avian cholera follows. Infected birds will die 6–12 hours after contracting the bacterium, and very few ill birds have been described. Due to association and dense aggregations, waterfowl are most commonly affected by P. multocida, however scavengers and other water birds are often affected in large multi-species outbreaks.

Clinical signs and post-mortem lesions

In acute cases, a green diarrhoea can be an early symptom.

The most typical symptom, in chronic cases, is the swelling of the wattles

Wattle (anatomy)

A wattle is a fleshy dewlap or caruncle hanging from various parts of the head or neck in several groups of birds, goats and other animals. In some birds the caruncle is erectile tissue.The wattle is frequently an organ of sexual dimorphism...

. It is more frequent in resistant local breeds. Rather than a general infection, localized infections are more characteristic. These often occur in the respiratory tract including the sinuses and pneumatoics bones, hock joints, sternal bursa, foot pads, peritoneal cavity and oviducts.

In acute cases, the most typical p.m. lesion is the petechia

Petechia

A petechia is a small red or purple spot on the body, caused by a minor hemorrhage ."Petechiae" refers to one of the three major classes of purpuric skin conditions. Purpuric eruptions are classified by size into three broad categories...

e observed in the epicardial fatty tissue. Necrotic foci

Necrosis

Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...

 on liver

Liver

The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...

 are usually found and general hyperemia is common. Due to the speed of infection and mortality, birds are in good body condition and do not exhibit the signs of prolonged illness.

Treatment

The most efficient treatment in breeding flocks or laying hens

Egg (food)

Eggs are laid by females of many different species, including birds, reptiles, amphibians, and fish, and have probably been eaten by mankind for millennia. Bird and reptile eggs consist of a protective eggshell, albumen , and vitellus , contained within various thin membranes...

 is individual intramuscular injections of a long-acting tetracyclines, with the same antibiotic in drinking water, simultaneously. The mortality and clinical signs will stop within one week. But the bacteria might remain present in the flock.

External links

• The Attenuation of the Causal Agent of Fowl Cholera, by Louis Pasteur, 1880
• Fowl cholera in the Merck Veterinary Manual