Oxidative Enzymes in Embryos from Dams Fed Synthetic and Practical Type Laying Diets. ∗

Summary

Enzymatic activity of embryos obtained from hens fed a synthetic-type laying diet, was compared to that of embryos from hens fed various supplements to the basal laying ration. Low hatchability of fertile eggs occurred in eggs of hens whose embryos had high cytochrome c reductase activity, high succinic dehydrogenase activity and high cytochrome oxidase activity. In all cases addition of corn, corn steepwater or a combination of soybean oil meal and corn to the hen basal diet improved hatchability of fertile eggs, and embryos from such groups exhibited lowered enzyme activity. Pyruvic reductase activity of embryos was increased when sources of unidentified factors were added to the basal diet of the dam. Increased hatchability of fertile eggs was also obtained from the dams fed these supplements. The embryos that hatched poorly seemed to be suffering from general debility rather than from any specific deficiency symptom.