The Effect of Level of Sinapine in a Laying Ration on the Incidence of Fishy Odor in Eggs From Brown-Shelled Egg Layers

Triplicate groups of four Rhode Island Red layers which had been previously found to lay fishy eggs when fed a ration containing 10% of rapeseed meal (RSM) were fed a laying ration, devoid of RSM, to which 0, 0.5, 1.0, 2.0 or 4.0 g of sinapine (as bisulfate) per kilogram of ration was added. Eggs produced were analyzed for trimethylamine and scored organoleptically for fishyness. Inclusion of more than 1 g of sinapine per kilogram of laying ration caused the birds to lay eggs with a fishy odor. The findings suggest that when RSM is included in the ration of such birds, the level of usage should be such that the ration will contain not more than 0.1% sinapine.