By Dr Trywell Muzerengi- The appearance of blood on an eggshell is often caused by irritation or minor injury to the hen’s vent (cloaca) during the laying process. In many cases, this is temporary, but farmers should understand the common reasons behind it to protect flock health.

1. The egg may be unusually large, stretching the vent and causing slight bleeding.
2. New layers often experience this because their reproductive systems are still adjusting.
3. Vent pecking from other birds can create small injuries that leave blood marks on the egg.
4. Internal parasites or infections may irritate the vent and make bleeding more likely.
5. Calcium deficiency can make eggs harder to pass, increasing strain on the hen.

What to do:

Provide adequate calcium sources such as oyster shell or grit. Reduce stress in the flock and avoid overcrowding. Check hens regularly for vent injuries and isolate any bird showing signs of irritation. Maintain strict hygiene in the coop and deworm consistently. Monitor the hen closely if blood marks persist.

This condition is generally not dangerous, but repeated bleeding should be watched carefully.