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The avian immune system is the system of biological structures and cellular processes that protects birds from disease. The avian immune system resembles that of mammals since both evolved from a common reptilian ancestor and have inherited many commonalities. [1] They have also developed a number of different strategies that are unique to birds.
Finally, their growth rates become suppressed, so they tend to die before the parasite becomes sexually mature and sheds eggs. Unlike young birds, older birds develop chronic eustrongylidosis because of their stronger immune systems. Similar to young birds, old birds have lesions in their ventriculi and develop secondary infections.
Infected birds pass on H5N1 through their saliva, nasal secretions, and feces. Other birds may pick up the virus through direct contact with these excretions or when they have contact with surfaces contaminated with this material. Because migratory birds are among the carriers of the H5N1 virus it may spread to all parts of the world.
The virus can spread rapidly through poultry flocks and among wild birds. [4] An estimated half a billion farmed birds have been slaughtered in efforts to contain the virus. [2] Symptoms of A/H5N1 influenza vary according to both the strain of virus underlying the infection and on the species of bird or mammal affected.
The main sign of Pacheco's disease is a sudden and rapid death of birds. It is often preceded by short, severe illnesses, which includes diarrhoea , lethargy , anorexia and inactivity. [ 7 ] [ 8 ] The virus is transmitted between birds through ingestion, by contaminated food or water, as well as through inhalation and conjunctival exposure. [ 8 ]
In birds, the bursa of Fabricius (Latin: bursa cloacalis or bursa Fabricii) is the site of hematopoiesis.It is a specialized organ that, as first demonstrated by Bruce Glick and later by Max Dale Cooper and Robert Good, is necessary for B cell (part of the immune system) development in birds.
In both cases, birds may appear weak and emaciated. [10] The infection of Avipoxvirus can lead to decreased egg production, reduced growth, blindness, and increased mortality in domestic poultry. In wild bird species, elevated predation, secondary infections, trauma, reduced male mating success, and death are common results. [9]
The immune system is a network of biological systems that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to bacteria, as well as cancer cells, parasitic worms, and also objects such as wood splinters, distinguishing them from the organism's own healthy tissue. Many species have two major ...