Poultry play a valuable role in the research laboratory. Chicks are used mainly to measure the biological availability of various nutrients. Because of their extremely fast rate of growth, chicks are used in nutritional biochemistry investigation in which metabolic pathways are of interest. To some degree they are valuable in assays for vitamins. Laying birds are valuable for producing eggs for virus cultures and related materials used in the production of biologicals.
Few research labs breed their own chicks. They are much more easily and inexpensively obtained from commercial hatcheries. The meat-producing chicken, a heavier breed, is most often used because they grow much faster than the lighter, egg-laying strains. But with the assay work for vitamin D3, where consistency of response is essential, the egg-laying purebred Leghorns are used.
Chicks are usually ordered from the hatchery already sexed, if that distinction is necessary. Unless the sex of the chick has been genetically linked with some other characteristic, such as a wing feather, chicks cannot be sexed reliably in the research laboratory.
Chicks need a well-ventilated, clean and uniformly lighted environment. Temperatures should be regulated according to their ages. When they first arrive at the lab, chicks should be put in battery brooders that have thermostatically controlled heating units. The brooder temperature should be decreased by five degrees each week, beginning at 95°F until the room temperature of 70 to 75°F is reached. The heat in the brooder can then be turned off. Temperatures in the chick's surrounding area should not vary more than half a degree form ceiling to floor.
The optimum relative humidity is 45-50% for chicks. At humidity levels below 40% the mucous lining of the chick's respiratory tract dehydrates, making the chick more susceptible to infection. Overcrowding, overheating or excessive lighting can lead to feather picking and cannibalism.