Also called as Mushy Chick Disease and Yolk sac infection

1. Omphalitis
(NAVEL ILL, “MUSHY CHICK” DISEASE, YOLK SAC INFECTION)
Rashika Srivastava
V/13/047

2. Introduction
Seen in chickens, turkeys and ducks.
Characterized by infected yolk sacs, often accompanied by unhealed navels in young
fowl.
Occurs due to bacterial infection of the navel and yolk sac of newly hatched chicks as a
result of contamination before healing of the navel.
 Disease occurs after an incubation period of 1-3 days.
 Infectious but noncontagious.
 Associated with poor regulation of incubation temperature or humidity and marked
contamination of the hatching eggs or incubator.
Morbidity is 1-10% and mortality is high in affected chicks.

3. Etiology
Opportunistic bacteria (coliforms, staphylococci, Pseudomonas spp,
and Proteus spp)
 Poor breeder farm nest hygiene, use of floor eggs, inadequate
hatchery hygiene or poor incubation conditions.
Inadequate incubation conditions resulting in excessive water
retention and slowly-healing navels and 'tags' of yolk at the navel on
hatching also contribute to the problem.

4. Signs
Dejection
Vent pasting
Closed eyes
Swollen abdomen
Loss of appetite
Diarrhoea

5. Post-mortem lesions
Enlarged yolk sac with congestion Abnormal yolk sac contents (colour, consistency)

6. Diagnosis
A presumptive diagnosis is based on the age and typical lesions.
Confirmation is by isolation and identification of the bacteria involved in the
internal lesions.
Differentiate from incubation problems resulting in weak chicks.

7. Treatment
No specific treatment.
Antibiotic use is based on the prevalent bacterial type involved.
Treatment may not result in satisfactory outcomes, because severely affected
chicks and poults often die.

8. Prevention
Prevention is based on a good programme of hygiene and sanitation.
 e.g. clean nests, frequent collection, sanitation of eggs, exclusion of severely soiled eggs,
separate incubation of floor eggs, etc.
Careful control of temperature, humidity, and sanitation in the incubator. Only clean,
uncracked eggs should be set.
The incubator should be cleaned and disinfected thoroughly between hatches. If
fumigation is to be done with formaldehyde, vents should be closed.
 The machines are readily contaminated after fumigation unless the exterior of the
machines and the rooms in which they are located are also cleaned and disinfected.
Multivitamins in the first few days may generally boost ability to fight off mild infections.