Baby chick born with fluid bubble on behind

[melaniemac]

Has anyone seen this before? Baby chick was born with what seems to be a fluid filled sac .. almost like a blister, on it’s behind. It’s eating and drinking and is not lethargic.

What could this be !?!

 

[MarlaMac]

Is it just below the vent? It is probably an absorbed yolk sac. Keep it moist and keep her away from the others so they don't peck it. It should absorb with in 48-72 hours.

Here is a synopsis.

An unabsorbed yolk sac in a newly hatched chick occurs when the chick fails to fully absorb the yolk sac into its abdomen before hatching, leaving a visible mass attached to the navel. This condition is often due to improper incubation conditions, such as low humidity during the final days of incubation, temperature fluctuations, or premature assisted hatching. The unabsorbed yolk sac acts as an open wound, significantly increasing the risk of yolk sac infection (omphalitis), a leading cause of death in young chicks.

Key Risks and Signs​

• Infection Risk: The exposed yolk sac is a prime entry point for bacteria like Escherichia coli, Staphylococcus aureus, and Salmonella, which can lead to septicemia.
• Clinical Signs: Lethargy, swelling at the navel, a moist or sticky area, foul odor, darkening of the tissue, and a "squishy" belly (known as "squishy chick syndrome").
• Mortality: Chicks with infected yolk sacs often die within 24–72 hours, with peak mortality between days 5–7 post-hatch.

What to Do​

• Do not pull or remove the yolk sac—it is still connected to blood vessels and removal can cause fatal bleeding.
• Keep the chick warm, dry, and clean in a separate brooder to prevent contamination and pecking from other chicks.
• Apply diluted antiseptic (e.g., povidone-iodine or chlorhexidine) to the area if irritated or moist.
• Use antibiotics (e.g., tetracycline or oxtetracycline) under guidance, especially if the sac is ruptured.
• Monitor closely—some chicks recover if infection is prevented and the navel closes naturally within 24–48 hours.

Prevention​

• Maintain proper humidity (65–75%) and temperature (99.5°F) during incubation, especially in the last 3–5 days.
• Disinfect incubators and eggs before use; avoid dirty or cracked eggs.
• Avoid early intervention—let chicks hatch naturally unless absolutely necessary.

While some chicks survive with a small unabsorbed yolk sac, infection is a major threat, and prompt care is critical. If signs of infection appear, seek veterinary advice immediately.

 

[melaniemac]

Thanks for your reply!

It is just below the vent. I’ve seen in unabsorbed yolk sacs on chicks that failed to hatch and it doesn’t look like those which is what is confusing me.

It’s really looks and feels like a giant blister? Not sure if you’re able to see the pics I’ve attached?

Thanks !

 

[Debbie292d]

Hi,

I've hatched hundreds and never seen that before. What I'd do is keep that one separated from the rest. You could maybe put one "calmer" chick with it so it doesn't cry. This is to keep it safe for the next couple of days, as that should absorb back into its body. It could get pecked/opened otherwise, which would invite bacteria and subsequent infection.

 

[melaniemac]

Thanks for the advice! I will do that and cross my fingers!