![Sample our Environment & Agriculture journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5934/TOC-Subject-Sample-2021-Environment-Agriculture.jpg"})
1. Three experiments with laying pullets were carried out in which rapeseed meals (B. napus and B. campestris) and a mustard seed meal (B. juncea) formed 12% of the diet.
2. Dietary rapeseed had no effect on the onset of lay when fed from 17 weeks of age but caused a delay when fed from 10 weeks of age: changing to a control soyabean diet for the laying period resulted in normal egg production.
3. Diets containing B. napus but not B. campestris consistently depressed egg production and reduced egg weight in one experiment. Mustard seed meal did not affect performance.
4. Significant number of eggs with a “fishy” taint were laid by brown‐egged birds fed on a diet containing rapeseed.
5. Thyroids of birds fed on rapeseed meal diets during the laying period were significantly heavier than those of birds fed on diets containing mustard seed or soyabean.
6. The enlargement of the thyroid gland is probably related to the oxazolidinethione content of the rapeseed.