Colibacillosis (Coliform infections in Poultry)
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Jogita Moirangthem
Colibacillosis is caused by E.coli ( one of the most important pathogens causing serious losses especially if favoured by bad management, stress in growing broilers and as complicating organisms in CRD and other respiratory diseases). The organism affects the birds of various age groups with varied clinical manifestations:
1. Colisepticaemia
2. Enteritis ( Infectious Asthemia)
3. Coligranuloma (Hjarre’s disease)
4. Arthritis and Bumble foot
5. Egg peritonitis
6. Air sacculiti
7. Omphalitis ( Yolk sac disease/ Mushy chick disease)
8. Panopthalmitis
1. Colisepticaemia
A disease of young broilers due to bad management and stress and characterized by fibrinous pericarditis and perihepatitis.
Pathogenesis:
Faecal contamination of eggs (penetration of E.coli due to negative pressure inside the eggs).
Birds with intact defence is resistant to E.coli.
When defence system is compromised it may cause disease.
Symptoms: Diarrhora, soiling of vent/cloaca with pasty faeces, depression, inappetance, dypsnoea & sneezing.
Pathology
Gross changes:
Fibrinous covering over liver and heart.
Milky fluid in the pericardium.
Liver congested and darker.
Microscopic changes:
Fibrinous pericarditis with infiltration of heterophils, macrophages and lymphocytes.
Necrosis of liver with fibrinous and purulent exudate.
Enteritis (Infectious Asthemia)
Oftenly affecting the broilers and occasionally adult birds(breeders)- 10 wks of age or grown up birds
Symptoms: Great emaciation, weakness and depression.
P.M. findings:
More or less confined to duodenum (Haemorrhagic inflammation).
Wasting of breast muscles and legs.
Chicks may show ulcerative lesions in duodenum.
Coligranuloma (Hjarre’s disease)
A sporadic chronic disease of adult birds characterized by the presence of nodules in intestines.( Hjarre described in 1945).
P.M. findings:
Presence of nodules on intestine.
Small millet size or large nodules on duodenum, caecum, liver and sometimes on gizzard, lungs and kidneys.
On cut nodules show caseous material.
Microscopically, caseous necrosis in centre, lymphocytes and giant cells around the necrotic centre, as in T.B. nodules.
Arthritis and Bumble foot
It produces lameness in birds. Hock joints are commonly affected. Pus may remain localised in the articular cavity. There may be abscess of foot pad. E.coli may be associated with Bumble foot which is a hard, fibrous swelling with ulceration of foot pad caused by Staph. sp.
Egg peritonitis
Common in layers & breeders where A.I. is practiced. Thought that E.coli gain entry into oviduct due to antiperistalsis of oviduct, produced by some unknown causes or due to impaction of large egg or during A.I. The organism then reach peritonium through the oviduct.
Lesions:
•
Presence of yellowish fibrinous or fibrino-purulent material in the peritonial cavity.
Salpingitis is commonly observed- oviduct plugged with yellowish caseous material.
6. Air sacculitis
It is common in growers especially broilers of 5-12 wks old. It usually occurs along with Mycoplasma gallisepticum infection as CRD.
Symptoms: Gasping and dypsnoea ( Common in overcrowded environment).
Lesions:
Cloudiness in air sacs.
Increased thickening of air sacs.
Milky fluid in the pericardium.
(To be contd)
Colibacillosis is caused by E.coli ( one of the most important pathogens causing serious losses especially if favoured by bad management, stress in growing broilers and as complicating organisms in CRD and other respiratory diseases). The organism affects the birds of various age groups with varied clinical manifestations:
1. Colisepticaemia
2. Enteritis ( Infectious Asthemia)
3. Coligranuloma (Hjarre’s disease)
4. Arthritis and Bumble foot
5. Egg peritonitis
6. Air sacculiti
7. Omphalitis ( Yolk sac disease/ Mushy chick disease)
8. Panopthalmitis
1. Colisepticaemia
A disease of young broilers due to bad management and stress and characterized by fibrinous pericarditis and perihepatitis.
Pathogenesis:
Faecal contamination of eggs (penetration of E.coli due to negative pressure inside the eggs).
Birds with intact defence is resistant to E.coli.
When defence system is compromised it may cause disease.
Symptoms: Diarrhora, soiling of vent/cloaca with pasty faeces, depression, inappetance, dypsnoea & sneezing.
Pathology
Gross changes:
Fibrinous covering over liver and heart.
Milky fluid in the pericardium.
Liver congested and darker.
Microscopic changes:
Fibrinous pericarditis with infiltration of heterophils, macrophages and lymphocytes.
Necrosis of liver with fibrinous and purulent exudate.
Enteritis (Infectious Asthemia)
Oftenly affecting the broilers and occasionally adult birds(breeders)- 10 wks of age or grown up birds
Symptoms: Great emaciation, weakness and depression.
P.M. findings:
More or less confined to duodenum (Haemorrhagic inflammation).
Wasting of breast muscles and legs.
Chicks may show ulcerative lesions in duodenum.
Coligranuloma (Hjarre’s disease)
A sporadic chronic disease of adult birds characterized by the presence of nodules in intestines.( Hjarre described in 1945).
P.M. findings:
Presence of nodules on intestine.
Small millet size or large nodules on duodenum, caecum, liver and sometimes on gizzard, lungs and kidneys.
On cut nodules show caseous material.
Microscopically, caseous necrosis in centre, lymphocytes and giant cells around the necrotic centre, as in T.B. nodules.
Arthritis and Bumble foot
It produces lameness in birds. Hock joints are commonly affected. Pus may remain localised in the articular cavity. There may be abscess of foot pad. E.coli may be associated with Bumble foot which is a hard, fibrous swelling with ulceration of foot pad caused by Staph. sp.
Egg peritonitis
Common in layers & breeders where A.I. is practiced. Thought that E.coli gain entry into oviduct due to antiperistalsis of oviduct, produced by some unknown causes or due to impaction of large egg or during A.I. The organism then reach peritonium through the oviduct.
Lesions:
•
Presence of yellowish fibrinous or fibrino-purulent material in the peritonial cavity.
Salpingitis is commonly observed- oviduct plugged with yellowish caseous material.
6. Air sacculitis
It is common in growers especially broilers of 5-12 wks old. It usually occurs along with Mycoplasma gallisepticum infection as CRD.
Symptoms: Gasping and dypsnoea ( Common in overcrowded environment).
Lesions:
Cloudiness in air sacs.
Increased thickening of air sacs.
Milky fluid in the pericardium.
(To be contd)