Abstract
Using White Leghorn hens, including those with an artificial anus, which had been laying for eight months from their first eggs, the experiments were conducted to know the nutritive value of rape seed meal as replacement of soybean meal in laying ration for egg production and digestion.
The four samples of rape seed meal used in these experiments (C-1, C-2, J-1, J-2) were the same as those used in Part I.
The results were as follows.
1. The digestibility of crude protein in rape seed meal was 70-76%, which was not very much different from those in the previous report, but TDN content of rape seed meal was 30-37%, which was lower than 42% in the previous report.
2. When rape seed meal was used as replacement for 10% soybean meal in laying ration, no significant difference was observed in egg production, egg weight, feed intake per hen per day and feed conversion.
3. The thyroid gland of the laying hens on ration containing rape seed meal as replacement of 10% soybean meal was enlarged significantly. It was noted that the enlargement was more remarkable when on rape seed meal of Japanese origin than that of Canadian product.
4. The weight of thyroid gland per kg body weight of the laying hen fed rape seed meal showed a tendency to the enlargement as the same as that of a chick at 4 weeks of age.
