rapeseed meal

laying performance

egg quality

egg taint

One hundred and seventy-five laying hens each of lines Hy-Line and ISA Brown were divided into seven groups of 25 birds and maintained in individual cages from the age of 26 weeks for 9 months of laying. The hens were fed isoprotein and isocaloric diets containing 16.7% crude protein and 11.4 MJ/kg. In the experimental diets, 45, 60 or 100% of the protein of soyabean meal was replaced by protein from regular rapeseed meal (R-RSM) or fractionated rapeseed meal (S-RSM) containing 11% more protein and 14% less crude fibre. Every 8 weeks egg and egg shell quality were assessed on 15 eggs per group; twice during the experiment egg odour was assessed on eggs from all of the hens. The use of rapeseed meal, both R-RSM and S-RSM, had no effect on laying rate parameters of egg and egg shell quality. As the content of rapeseed meal in the diet increased, the weight of eggs decreased (P<0.01). Among the hens fed the ration containing rapeseed meal, 3.4% of the Hy-Line and 7.4% of the ISA Brown hens laid eggs with a fishy odour. The type of rapeseed meal and its content in the diets had no effect on the occurrence or intensity of the non-specific odour of eggs.