Adsorbing Charcoals in Chick Diets

Abstract

It has long been a common practice to add charcoal to poultry feeds, under the impression that charcoal improves the health and reduces the mortality rate of chickens. Acceptable evidence for these alleged attributes has been lacking. Charcoal is claimed to act by adsorbing undesirable products from the digestive tract, for example, one manufacturer of poultry charcoal lists the following substances as removed: carbon dioxide, ammonia, bacteria, pigments, poisons and enzymes.

Charcoal is known to cause a bleaching of poultry flesh and of egg yolk by reducing the deposition of carotenoid pigments from the diet. This bleaching effect suggests the possibility that carotene and other vitamins in the diet might also be removed or inactivated by charcoal. For example, former experience in this laboratory showed that vitamin K is adsorbed strongly on charcoal and that it cannot later be removed without much destruction. The vitamin K-deficient chicken fed vitamin K adsorbed on charcoal seems unable to remove and utilize the vitamin. 1

A diet was formulated to provide optimum amounts of vitamins A, K, G (riboflavin) and the chick gizzard factor, without the considerable margins of safety that exist in most good commercial chick mashes. This diet was found capable of promoting normal growth and health of chicks.