Omphalitis is an infection of the navel or yolk sac in young poultry. It is more likely to be found in unclean environments, which promote opportunistic bacterial infections. Clinical signs include navel inflammation, anorexia, listlessness, decreased weight gain, and death in the first 2 weeks after hatching. Treatment of affected birds with antimicrobials is often ineffective. Prevention is by improving sanitation and general husbandry.
Omphalitis is a condition characterized by infected yolk sacs, often predisposed by unhealed navels in young fowl. Unhealed navels are commonly associated with poor regulation of incubation temperature or humidity and marked contamination of the hatching eggs or incubator. Chicks may also be infected from surviving infected chicks from the same hatch.
Etiology of Omphalitis in Poultry
The primary cause of omphalitis in poultry is contact of an open navel with contaminated surfaces. If young poultry are in contaminated environments (including dirty eggshells) before their navels are completely closed, bacteria can migrate up the patent yolk stalk and infect the yolk sac. Surviving infected chicks may infect other chicks in the same hatch. Opportunistic bacteria (coliforms, staphylococci, streptococci, Enterococcus spp, Pseudomonas spp, and Proteus spp) are often involved, and mixed infections are common.
Omphalitis is associated with poor regulation of incubation temperature and humidity and enhanced by marked contamination of hatching eggs, incubators, or transportation boxes. Chilling or overheating during shipment or early placement may increase losses. Escherichia coli and Enterococcus faecalis infections account for about half of omphalitis deaths in the first week after hatching.
Clinical Signs of Omphalitis in Poultry
In poultry with omphalitis, the navel may be inflamed and fail to close. Physical examination reveals a wet spot on the abdomen; a scab may be present (see unhealed navel image).
Affected birds are listless and anorectic; their heads droop and they huddle near heat sources. They fail to gain weight, and mortality rate increases from hatch to two weeks old. Affected chicks or poults usually appear normal until a few hours before death. Losses of up to 15% in chickens and 50% in turkeys have been observed.
Lesions
Young fowl are dehydrated and have a persistent, unabsorbed yolk in the body cavity, which may be congested and malodorous and may contain solidified yolk material (see yolk sac infection image). Peritonitis may be extensive.
Courtesy of Dr. H. John Barnes.
Courtesy of Dr. H. John Barnes.
Treatment and Prevention of Omphalitis in Poultry
There is no specific treatment for omphalitis in poultry; antimicrobial use is based on the prevalent bacterial type involved. Even then, treatment may not result in satisfactory outcomes because severely affected chicks and poults often die, and unaffected birds are unlikely to be aided by antimicrobial treatment.
Omphalitis is prevented by careful control of temperature, humidity, and sanitation in the incubator. Only clean, uncracked eggs should be set. If it is necessary to set dirty eggs, they should be segregated from clean eggs and set at the bottom of the incubator.
Sanitizing detergents must be used according to directions if eggs are washed. Time, temperature, and frequent changes of water are as critical as the concentration of sanitizer in both wash and rinse water. The rinse water should be warmer than the wash water (which should be warmer than the internal temperature of the egg) but should not be > 60°C.
The incubator should be cleaned and disinfected thoroughly between hatches. If fumigation is to be done with formaldehyde, vents should be closed. A solution of 40% formaldehyde (30 mL/0.6 m3) or paraformaldehyde (in the strength recommended by the manufacturer), should be allowed to evaporate in the closed incubator or hatcher. 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.
Omphalitis can be exacerbated by poor brooding conditions; ensuring litter is sufficiently prewarmed before chick placement is key.
Key Points
Omphalitis is a bacterial disease of environmental origin in young poultry.
It results in morbidity and elevated mortality rates early in life.
Treatment is often ineffective, so prevention through improved sanitation, especially in the hatchery, is recommended.
For More Information
Nolan LK, Vaillancourt JP, Barbieri NL, Logue CM. Colibacillosis. In: Swayne DE, ed. Boulianne M, Logue CM, McDougald LR, Nair V, Suarez DL, associate eds. Diseases of Poultry. 14th ed. Wiley; 2020:770-830.
Yousef HMY, Hashad ME, Osman KM, et al. Surveillance of Escherichia coli in different types of chicken and duck hatcheries: one health outlook. Poult Sci. 2023;102(12):103108. doi:10.1016/j.psj.2023.103108
