ELEVATION OF BIOTIN ACTIVITY IN THE SERUM OF ESTROGEN TREATED CHICKS; RELATIONSHIP TO HORMONE-INDUCED AVIDIN FORMATION IN THE OVIDUCT

Abstract
Considerable information has accumulated concerning the factor in egg-albumen that neutralizes the biological effectiveness of biotin (Hertz, 1946). This factor has been termed “Avidin” (Eakin et al., 1941) and its presence in both the egg and in the genital tract of several species of birds and amphibia has been demonstrated (Hertz et al., 1942). Moreover, the formation of avidin has been found to be associated with ovarian function in the actively laying hen and avidin production has been experimentally induced in the oviduct of the sexually immature chick by the administration of estrogen followed by progesterone (Fraps, Hertz and Sebrell, 1943; Hertz, Fraps, and Sebrell, 1943). Trager has described the presence of a fat-soluble factor (FSF) in the plasma of the hen which has biotin-like activity for both the chick and for Lactobacillus casei (Trager, 1947, a). He noted further that this biotin-like factor is elevated in the plasma of the actively laying hen (Trager, 1948).