How long does an egg spend in the Isthmus?

An egg spends approximately 1.25 hours in the Isthmus, which is the section of the hen's oviduct where the inner and outer shell membranes are formed. During this phase, the egg undergoes crucial development, as the membranes provide essential support and protection for the developing embryo. This timing is important because the formation of the membranes is a critical step before the egg moves on to the Uterus, or shell gland, where the eggshell is deposited. Understanding this duration helps poultry science students and professionals grasp the overall timeline of egg development and the biological processes involved in poultry reproduction.