Observe before sorting
A stained shell can have two main origins: dirt deposited after laying or discolouration that appeared during egg formation. To tell the difference, examine the egg under good lighting, with clean hands, and observe the colour, texture and location of the mark.
Brownish or greenish marks spreading across the surface, droppings splashes, stuck feathers or moisture marks generally suggest external contamination. They are often irregular and can sometimes be gently removed with a dry cloth. Do not scrape the shell and avoid washing eggs with water without an appropriate procedure: moisture can encourage microbes to pass through the shell.
Conversely, discolouration that is part of the shell, regular or repeated on several eggs, may correspond to the hen’s natural pigmentation. A mark that does not come off when touched is therefore not necessarily dirt. Calcium deposits, rough areas, very thin, misshapen or cracked shells are more likely to be shell abnormalities than simple stains.
Look for the cause in the poultry house
Dirty eggs often appear when nest boxes are soiled, too damp or poorly lined, or when hens lay on the floor. Collect eggs regularly, keep the litter dry and remove soiled material from the nest boxes. Also check that they remain accessible and sufficiently quiet, to limit laying outside the nests.
If several eggs have fragile, rough or misshapen shells, check the quality of the feed, its storage and its constant availability. Calcium and the overall balance of the ration contribute to shell formation. A persistent change in the appearance of eggs, especially if accompanied by a drop in laying rate or signs of disease, warrants advice from a technician or a veterinarian. Do not add supplements at random.
Adapt sorting to the intended use
For consumption, set aside cracked and heavily soiled eggs, and follow the hygiene and storage rules in force. For incubation, be even more demanding: a cracked or very dirty shell increases the risk of contamination. Do not put a questionable egg into incubation without following an appropriate health protocol.
In Côte d’Ivoire, start by inspecting the eggs, nest boxes and litter as soon as stains appear. Note what keeps recurring, correct the cause in the poultry house and seek advice if the defects persist: acting early protects the quality of collection and the health of the flock.
--- *Source: NEXTEKCI — In-house expertise — summary and analysis by NEXTEKCI.*