The Effect of Pteroylglutamic Acid and an Unidentified Factor on Egg Production and Hatchability1
W. W. Cravens and
J. G. Halpin
Department of Poultry Husbandry, University of Wisconsin, Madison
1. Four experiments with breeding chickens have been describedwhich demonstrate the importance for hatchability of an unidentifiedfactor or factors.
2. Fish solubles and liver fraction L aregood sources of thefactor or factors.
3. The breeding henmay be depleted of the factor in from 46weeks when purifieddiets are used.
4. Data are presented which indicate thatdextrin favors theintestinal synthesis of the factor in themature fowl.
5. The pteroylglutamic acid requirement of thelaying bird isprobably not over 0.25 mg per kilogram of diet.
6. The pteroylglutamic acid requirement of the breeding birdappears to be approximately 0.51.0 mg per kilogram ofdiet when a diet is employed which does not favor intestinalsynthesis of the vitamin.
7. Evidence is presented which indicatesthat pteroylglutamicacid synthesis in the intestinal tractof the breeding hen isfavored by diets containing dextrin asa carbohydrate.
1 Published with the approval of the Director of the WisconsinAgricultural Experiment Station. This study was supported inpart by a grant from the International Baby Chick Association,Kansas City, Missouri.