Influence of dietary rapeseed meals and selenium on egg production and egg tainting in laying hens

In 3 experiments 152 hens of differing strains were fed diets containing 0, 50 or 100 g Span, Canadian or European rapeseed meal per kg. Two strains, Shaver 288 and Babcock B300, laid white‐shelled eggs while three other strains, Shaver 585, Warren 14 and Thomber 404 laid brown‐shelled eggs. Egg production performance was not significantly affected by the inclusion of rapeseed meal in the diet. However the strains laying brown‐shelled eggs laid a high proportion of tainted eggs when rapeseed meal was included in the diet. All rapeseed meals led to a similar degree of tainting. Supplementing the diets with 1 or 2 mg selenium per kg did not significantly affect the incidence of tainting. Shell thickness, albumen height and Haugh unit were unaffected by the presence of rapeseed meal in the diet, and yolk colour was improved by the inclusion of Canadian and European rapeseed meals. On the basis of these and other findings it is recommended that rapeseed meal be omitted from diets at least for hens that lay brown‐shelled eggs until the taint problem has been solved.