Bielorai, R., Division of Animal Nutrition, Volcani Institute of Agricultural Research, Rehovot, Israel

In vitro experiments showed that there is less trypsin‐inhibiting activity in raw groundnut meal (RG) than in raw soyabean meal (RS). Some of the typical effects which were observed in chicks fed RS were seen also in chicks fed RG, but to a different extent, i.e. growth retardation, pancreas hypertrophy, and a high percentage of intestinal nitrogen precipitated by trichloracetic acid. These effects were not obtained in chicks fed toasted groundnut meal or in those fed toasted soyabean meal. Some relationships between in vitro experiments and growth retardation, pancreas hypertrophy and the undigestible nitrogen fraction in the intestine of chicks fed RG and RS are discussed. Copyright © 1969 John Wiley & Sons, Ltd