Download E. coli infection.

BY:asst.prof.Dr.firas AL-bawi
Escherichia coli Infections (Colibacillosis)
Colibacillosis refers to any localized or systemic infection caused entirely
or partly by avian pathogenic Escherichia coli (APEC), including
colisepticemia, coligranuloma (Hjarre’s disease), air sac disease (chronic
respiratory disease, CRD), venereal colibacillosis, swollen-head syndrome,
coliform peritonitis, orchitis, panophthalmitis, omphalitis/yolk sac
infection, and enteritis salpingitis, coliform osteomyelitis/synovitis and
coliform omphalitis/yolk sac infection.
ETIOLOGY
 The etiology of colibacillosis is Escherichia coli.
 The bacterium Escherichia coli which is in the family
Enterobacteriaceae meaning it is found in the intestine: this organism
is coliform, gram negative, and motile.
 Most problems in poultry are caused by somatic antigen serotypes 01,
02, and 078.
 Other infectious agents and noninfectious factors usually predispose
an animal to infection.
Natural and Experimental Hosts
 Most, if not all avian species, are susceptible to colibacillosis.
 Clinical disease is reported most often in chickens, turkeys, and ducks.
Transmission, Carriers, and Vectors
 E. coli is present in the intestinal tracts of most animals and shed in
the feces, often in high numbers.
 Direct or indirect contact with other animals or feces can introduce
new strains into the poultry flock.
Localized infections
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Coliform omphalitis/yolk sac infection
Coliform cellulitis (inflammatory process)
Swollen head syndrome
Diarrheal disease
Venereal colibacillosis (acute vaginitis)
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BY:asst.prof.Dr.firas AL-bawi
 Coliform salpingitis/peritonitis/salpingo-peritonitis (adult)
 Coliform orchitis/epididymitis/epididymo-orchitis
Systemic infections
Colisepticemia
Respiratory-origin (air sac disease,
chronic respiratory disease, CRD)
Hemorrhagic septicemia
Meningitis/encephalitis
Panophthalmitis
Osteomyelitis
Arthritis/polyarthritis
Synovitis/tenosynovitis
Coligranuloma
Chronic fibrosing pericarditis
Salpingitis (juvenile)
Sternal bursitis
Localized Forms of Colibacillosis
Coliform Omphalitis/Yolk sac Infection
 Omphalitis is an inflammation of the navel (umbilicus). In birds, the
yolk sac usually is involved, Infection follows contamination of the
unhealed navel with virulent strains of E. coli.
 Fecal contamination of eggs is considered to be the most important
source of infection. Bacteria may be acquired in ovo if the hen has or
salpingitis or via contamination following artificial insemination.
 Swelling, edema, redness, and possibly small abscesses characterize
acute inflammation of the navel of affected birds. The abdomen is
distended, and blood vessels are hyperemic. In severe cases, the body
wall and overlying skin undergo lysis and are wet and dirty.
 These birds are referred to as mushy chicks or poults E. coli often
persists in the inflamed yolk sac for weeks or months.
Coliform cellulitis:
Is caused by Escherichia coli and characterized by sheets of
serosanguineous to caseated, fibrinoheterophilic exudate in
subcutaneous tissues. Lesions, often referred to as “plaques,” are
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BY:asst.prof.Dr.firas AL-bawi
located in the skin over the abdomen or between the thigh and
midline.
Swollen head syndrome (SHS):
Is an acute to subacute cellulitis involving the periorbital and adjacent
subcutaneous tissues of the head Swelling of the head is caused by
inflammatory exudate beneath the skin that accumulates in response
to bacteria, usually E. coli, following upper respiratory viral
infections (e.g., avian metapneumovirus, infectious bronchitis virus).
Ammonia aggravates the disease.
Salpingitis/Peritonitis (Adult).
 Inflammation of the oviduct caused by E. coli results in decreased egg
production and sporadic mortality in laying chickens and breeders.
Systemic infections:
Colisepticemia:
 The presence of E. coli in the blood stream characterizes
Colisepticemia.
 Virulence of the organism and efficiency of the host defenses
determine the duration, degree, and outcome of the disease, as well as
the pattern and severity of lesions
 Colisepticemia progresses through the following stages: acute
septicemia, subacute polyserositis, and chronic granulomatous
inflammation.
Panophthalmitis:
 involvement of the eye is uncommon. However, if it is infected the
resulting panophthalmitis unilateral The eye is swollen, cloudy to
opaque, and may be hyperemic initially. Later the eye shrinks as it
undergoes atrophy.
 Fibrinoheterophilic exudate and numerous bacterial colonies are
present throughout the eye. Inflammation, especially adjacent to
necrotic tissue, becomes granulomatous with time.
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BY:asst.prof.Dr.firas AL-bawi
Coligranuloma (Hjarre’s Disease):
 Coligranuloma of chickens and turkeys is characterized by multiple
granulomas in liver, ceca, duodenum, and mesentery but not in the
spleen.
 Coligranuloma is an uncommon form of systemic colibacillosis that
usually occurs sporadically in individual birds, but can cause
mortality as high as 75% when a flock is affected.
 Lesions resemble leukosis tumors.
Osteoarthritis and Synovitis.
 Localization of E. coli in bones and synovial tissues is a common
sequel to colisepticemia lead to Mild to severe lameness and poor
growth.
DIAGNOSIS
 Isolation and Identification of Causative Agent
Differential Diagnosis:
 Many other organisms including viruses, mycoplasmas, and other
bacteria can cause synovial lesions similar to those resulting from E.
coli infection.
◦ Mycoplasma
◦ Respiratory virus – ND, IB
◦ Staph Infection
◦ Fowl Cholera
◦ Blackhead
◦ Erysipelas
◦ Salmonella
◦ Other bacterial septicemias
PREVENTION, CONTROL, AND TREATMENT:
 Management Procedures
 Immunization
◦ Inactivated Vaccines
◦ Live Vaccines
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BY:asst.prof.Dr.firas AL-bawi
Treatment:
E. coli may be sensitive to many drugs such as ampicillin,
chloramphenicol, chlortetracycline, neomycin, nitrofurans,
gentamicin, or methiprim-sulfadimethoxine, nalidixic acid,
oxytetracycline, polymyxin B, spectinomycin,streptomycin, and sulfa
drugs.
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