How long can a fertilized chicken egg last with out heat?

A fertilized chicken egg can only last a few days without heat. Here's why:

* Embryonic Development: The developing chick inside the egg needs a consistent warm temperature (around 99.5°F or 37.5°C) for proper development.

* Cold Temperatures: If the egg is exposed to cold temperatures, the embryo's growth will slow down and eventually stop. The egg will become infertile.

* Timeframe: While the exact duration varies, a fertilized chicken egg will typically remain viable for 3-5 days without incubation. After that, the embryo will likely die.

Important Note: Even if the egg is kept at room temperature, the chances of successful hatching decrease significantly after a few days. For optimal hatching rates, it's crucial to incubate the egg within 24 hours of laying.