GROWTH DEPRESSING FACTORS IN RAPESEED OILMEAL: III. STUDIES ON COUNTERACTION BY STEAM PROCESSING, EXTRACTION AND DIETARY SUPPLEMENTS

Abstract

Four feeding and growth experiments have been conducted with mice that received diets containing rapeseed oil meal treated by various steam processings, by extractions with hot or cold water, by extractions with ether or alcohol, by partial or complete sterilization of the diet, and by acid hydrolysis of different fractions of rapeseed oil meal. The effects of supplemental iodine (0.01 and 0.003 per cent), iodinated casein (0.5 per cent), antibiotics, vitamin B12 and certain enzyme inhibitors were studied.Steam cooking up to 15 lb. pressure for 20 minutes was of little value. Aureomycin at 50 p.p.m. or a combination of aureomycin and terramycin at 200 p.p.m. did not counteract the toxic factor but apparently enhanced vitamin B12 nutrition. Vitamin B12 effected some improvement. Water extraction, particularly with hot water, reduced the growth-inhibitor effect, as did hot alcohol extraction.The feeding of 0.01 per cent I depressed growth in mice fed rapeseed oilmeal but 0.003 per cent I gave no response. Ionidated casein depressed growth. The enzyme inhibitors tested had no effect on gains or feed intakes.A total of 408 mice was involved in the experiments.