Changes

==Description==  

==Description==  

Listeriosis is a bacterial infection caused by [[Listeria species - Overview|''Listeria'' species]]. It affects a wide range of animals and is an important zoonosis.. ''L.monocytogenes'' is found in silage and is the main source of contamination for animals. Soil and the mammalian gastrointestinal tract are natural reservoirs for L.monocytogenes and if ingested by grazing animals the bacteria will further contaminate the pasture.  The bacteria is very resistant to drying and can survive at a variety temperatures and PH.

Listeriosis is a bacterial infection caused by [[Listeria species - Overview|''Listeria'' species]]. It affects a wide range of animals and is an important zoonosis.. ''L.monocytogenes'' is found in silage and is the main source of contamination for animals. Soil and the mammalian gastrointestinal tract are natural reservoirs for'' L.monocytogenes'' and if ingested by grazing animals the bacteria will further contaminate the pasture.  The bacteria is very resistant to drying and can survive at a variety of temperatures and PH.

Lumbosacral CSF can be collected under local anaesthesia and if the animal is infected will show an increased protein count and mild pleocytosis with large mononuclear cells.

Lumbosacral CSF can be collected under local anaesthesia and if the animal is infected will show an increased protein count and mild pleocytosis with large mononuclear cells.

Isolation of ''L. monocytogenes'' provides a definitive diagnosis of listeriosis. The preferred samples for culture are brain, aborted foetus or placenta.

Isolation of ''L. monocytogenes'' provides a definitive diagnosis of listeriosis. The preferred samples for culture are brain, aborted foetus or placenta.

Immunofluorescence can also be used to identify L.monocytogenes on smears taken from dead or aborted animals.

Immunofluorescence can also be used to identify ''L.monocytogenes'' on smears taken from dead or aborted animals.

Serology is not used as many healthy animals have high ''Listeria'' titres.

Serology is not used as many healthy animals have high ''Listeria'' titres.

==History and Clinical Signs==

==History and Clinical Signs==

The most recognised form of listeriosis in ruminants affects the nervous system causing meningoencephalitis. Animals present depressed, sometimes with a head tilt, facial paralysis, a drooping eyelid and often circling. This can lead to recumbency and death within 24-48 hours. In monogastric animals and young ruminants listeriosis causes septicaemia.  

The most recognised form of listeriosis in ruminants affects the nervous system causing meningoencephalitis. Animals present depressed, sometimes with a head tilt, facial paralysis, a drooping eyelid and often circling. This can lead to recumbency and death within 24-48 hours.  

In monogastric animals and young ruminants listeriosis causes septicaemia.  

If animals are infected whilst pregnant this can cause abortion up to 12 days later. Following abortion the animal will often recover normally unless the foetus is retained when septicaemia will follow.

If animals are infected whilst pregnant this can cause abortion up to 12 days later. Following abortion the animal will often recover normally unless the foetus is retained when septicaemia will follow.

Listeriosis can also manifest as conjunctivitis when infected silage come in contact with the animals eye, pneumonia, myocarditis and endocarditis.

Listeriosis can also manifest as conjunctivitis when infected silage come in contact with the animals eye, pneumonia, myocarditis and endocarditis.