Monograph

Mon, 01/24/2011 - 16:39 — Anonyme

definition:

Avian colibacillosis is an infectious disease of bacterial origin that affects domestic and wild birds. It is one of the biggest causes of economic losses in the poultry sector.

Situation in America:

Avian colibacillosis is present throughout the world.

Susceptible species:

All mammals

Etiological agent:

Colibacillosis is caused by Escherichia coli, a Gram-negative, reduced mobility, isolated or grouped in two, sometimes capsulated coccobacillus.

Methods of transmission

Transmission:

In adult subjects, transmission of the disease primarily occurs through the inhalation of infected dust particles (litter, excrement).

Method of contamination:

The ingestion of contaminated water can also cause contamination. Contamination of eggs, and more specifically the vitelline membrane, occurs during passage through the cloacae during egg lying.

Symptoms:

There are diverse clinical expressions of colibacillosis depending on the affected subject:

- In chicks: embryonic death shortly before hatching, poor quality shells with a humid and hot surface. Death can occur up to three weeks after hatching. Sometimes delays in the involution of the vitelline vesicle and associated omphalitis

- Animals aged 2 to 9 weeks: septicemia and chronic respiratory disease (secondary contamination by Mycoplasma gallisepticum infection), primary expression of colibacillosis, causing major losses: Significant decline in food consumption followed by exhaustion, hypothermia and signs of respiratory distress in the most affected subjects. Death in 30% to 50% of cases

- Animals aged several months: ovaritis and salpingitis, ascending chronic infection or through the spread of bacteria from the left air sac to the oviduct

- Animals aged 30 weeks: swollen head syndrome (secondary contamination by viral infection): acute inflammation of cells in the skin and the subcutaneous tissue of the head and periorbitary regions

Diagnostics

Laboratory diagnosis:

- Detection of the pathogenic agent through isolation and identification on the basis of biochemical reactions (production of indole, fermentation of glucose in an aerobic environment, etc.)

- Detection of antibodies using an ELISA test

Prophylaxis:

Sanitary

Adherence to standard hygiene measures (sufficient aeration, avoiding overcrowding, clean litter, etc.)

Fumigation and/or soaking of eggs in a tepid disinfectant solution

Vaccines:

No vaccine