Concentrations of antisecretory factor in eggs and in chicken blood plasma

1. In the present study, the concentration of antisecretory factor (ASF), a lectin with hormone-like properties, and with the capacity to regulate water and electrolyte transport in the small intestine, was higher in hen's egg yolk than in egg white (1.20 v. 0.46 units/ml). 2. The blood plasma concentrations of ASF activity were higher in d-old chicks (1.03 units/ml) than in 7-d-old (0.42 units/ml) or 21-d-old birds (0.18 units/ml); the contents were found to be high again in 35-d-old chickens, but to have decreased by 60 to 90% after transport to slaughter 1 day later. 3. The amount of ASF activity was lower in two groups of chickens manifesting patent loose droppings at slaughter (0.15 units/ml in one group, and 0.08 units/ml in the other), than in two groups with normal faecal consistency (0.65 units/ml in one group, and 0.72 units/ml in the other). 4. The results demonstrate the presence of ASF in eggs, and a variation of ASF activity in chickens blood plasma in relation to age, stress and faecal consistency. The interpretation of these data suggests a regulatory influence of ASF on chicken intestinal transport of water.