Failure of Ferrous Sulphate to Inactivate Free Gossypol in Diets for Laying Chickens

Abstract

ABSTRACT SCHAIBLE and co-workers (1934) reported that free or bound gossypol is a cause of the olive, brown, and chocolate discolorations in the yolks of eggs from hens fed cottonseed products. One or two percent ferrous sulphate protected against the discolorations when rations contained as much as 40 percent cottonseed meal, but the gossypol content of the meal is not stated. Fletcher and co-workers (1953) fed New Hampshire hens a diet containing a mixture of equal parts of hydraulic and solvent-extracted cottonseed meals to furnish .03 percent free gossypol to the diet, and then stored the eggs at about 34 degrees F. for periods varying from 60 to 150 days. Only about five percent (6 of 117) of the eggs had slightly dark or dark discolored yolks when .50 percent ferrous sulphate was included in the diet, but about 93 percent (88 of 95) of the eggs had the discolorations when . . .