Listeriosis avian. Infectious disease that is manifested so septicemic and that may cause significant losses in poultry. Although Listeria monocytogenes it has been considered a pathogen in animals for a long period, its importance as an agent of the pathological in humans, transmitted through food, are clearly evidenced from 1980, when they begin to be documented outbreaks of listeriosis as a result of consumption of contaminated food. The bacteria responsible is Listeria monocytogenes.

The relevance of this disease lies in its nature zoonotic, which means that it can be transmitted to humans.

Birds are often subclinical carriers of this microorganism. Most infections in these animals are subclinical; however, listeriosis can occur sporadically or in epidemic outbreaks.

In addition to the economic effect associated with listeriosis in animals, there is a relationship between these and its role as a vector of infection to humans, either by direct contact with infected animals.

Avian listeriosis can occur as a secondary infection in the presence of viral infections or salmonellosis.

The birds that develop the phase septicemic present a significant deterioration, showing, in most cases, neurological abnormalities evident through postures anomalous inclinations of the head, torticollis, among other manifestations.

The findings suggest that the listeriosis in animals is predominantly a pathology of food-borne, being the environment, the main source of contamination of food.

The silage is identified as the most common source of listeriosis from food.

The intestinal mucosa constitutes the main route of entry, post-ingestion.

Typical lesions of the septicemic phase include the development of necrotic areas in various organs, such as:

• The heart.
• The liver.
• The spleen.
• And also bleeding in certain organs of the digestive system.

From the point of view of blood, this disease causes a monocytosis.

Currently, there are various methods—both conventional and rapid—available for the detection and identification of L. monocytogenes in food samples and samples related to animal listeriosis. Conventional bacteriological methods are of great importance for many reasons: their use enables the isolation of pure cultures of the microorganism, which is essential for regulatory purposes.

These methods are considered the “gold standard” against which to compare and validate other procedures.

The isolation and identification of L. monocytogenes from food, environmental, and clinical samples from animals requires the use of selective agents and enrichment techniques that keep the levels of contaminating microorganisms at appropriate levels and facilitate the proliferation of L. monocytogenes to levels sufficient for detection.