Albumen - The egg white.

Blood Feather - The stage of growth in a feather where the vein in a live quill carries nutrients to the growing feather.

Blood Ring - Circular blood remnant visible when an egg is candled, signifying that the embryo has died at a young age.

Botulism - Paralysis of the neck, caused from toxins ingested from boggy areas with rotting vegetation or animals.

Broody - A female bird who is preparing to sit or is sitting on eggs, characterized by vocal and physical defensive behavior when anyone approaches her nest.

Bumblefoot - A large swelling on the bottom of the foot caused by an infection - typically caused by a small cut.

Candling - Illuminating an egg with a bright light to determine the presence or absence of a viable embryo, or to look for shell defects prior to setting.

Cappillaria - Type of nematode that can be found in the esophagus, gullet, or small intestine; introduced via the consumption of earthworms or through drinking water in nature.

Clears - Incubated eggs that appear clear when candled, indicating that they do not contain a live embryo.

Coccidiosis - One-celled parasites in the gut of poultry, rarely a problem in waterfowl.

Crop - An enlargement of the gullet where food is conditioned for digestion.

Dewlap - A fold of skin, covered in feathers, that hangs from the throat or gullet in some geese.

Drake - Adult male of a wild or domestic duck.

Dry-Bulb Temperature - Temperature measured with a standard thermometer.

Duckling - A young duck.

Egg Bound - When a hen cannot pass her egg normally through the oviduct.

Embryo - An organism in the early stages of its development prior to hatching.

Follicular Cyst - When a feather follicle is facing the wrong way, so the feather is aimed and grows inside of the bird's body instead of outside.

Gosling - A young goose.


Gravid - term commonly used for a pregnant reptile; pregnant, carrying eggs or young


Hatch of Fertile Eggs, Hatchability - Percentage of fertile eggs that hatch (should be above 85%).

Hatch, Percent Hatch, Hatch Total - Percentage of all eggs set that hatch, whether they were fertile or not (a typical hatch might be 60% - 80%).

Hatcher - Machine used to maintain proper conditions for embryos during the final few days (usually 3) before hatching.

Inbreeding - The practice of mating closely related birds, such as father to daughter or brother to sister. As inbreeding increases, the ability of the stock to reproduce usually declines.

Incubation - Maintaining the temperature and humidity needed to initiate embryo growth and hatching of avian eggs by a female or using a machine.

Incubator or Setter - Machine that maintains proper conditions for incubating or setting eggs.

Keet - A young guinea.

Malposition - Hatching embryo in any position except the head under the right wing positioned in the large end of the shell. For example, the head under the left wing or the head between the legs.

Molt - The shedding of old feathers and replacing with new.

Niacin - A B-Complex vitamin that ducks and geese require in larger quantities than chickens. A niacin deficiency causes stunted growth, poor feathering, and crippled legs.

Pinfeathers - Newly emerging feathers after a molt. It is very difficult to pluck waterfowl with many pinfeathers.

Pinion - The surgical removal of the point of the wing at the outer joint. Done to permanently prevent the bird from being able to fly.

Pip - Egg in which the chick has broken the shell in an attempt to hatch; Also, the act of breaking the shell. 

Poult - A young turkey.

Preening - Lubricating feathers from the preening gland situated at the base of the rump. Waterfowl need to be wet in order to preen, so they need access to splashing water at least.

Relative Humidity - Measure of the water vapor or moisture in the air; can be determined from the wet-bulb temperature, dry-bulb temperature, and atmospheric pressure using a psychometric chart.

Set - To place eggs in an incubator or under a female for incubation.

Setter - An incubator.

Sex Link - A genetic trait that creates a difference (usually color) between males and females.

Sexing - Determining the gender of a bird. The only sure way to tell the sex of a duckling before they are 6 to 8 weeks old is to examine the cloaca (vent sex).

Sport - A colloquial term for mutation.

Straight Run - Young poultry that have not been sexed, usually meaning about 50% males and 50% females

True Fertility - Percentage of hatching eggs that are fertile. This can be determined only by candling the eggs after at least six days of incubation or by breaking open fresh eggs to examine the germinal disc on the yolk to see if it is fertile or not.

Wet-Bulb Temperature - Temperature measured by a standard thermometer equipped with a wet sock over the bulb. A lower wet bulb temperature indicates the incubator is dry, as there is so much evaporation of water off the sock that the thermometer is cooled. If the wet bulb temperature is close to the dry bulb temperature, it indicates that the incubator is very humid as there is very little evaporative cooling from the sock. Instead of buying a wet bulb sock, you can use a hollow shoelace.