The development of the stratum granulosum of the small intestine of the rainbow trout (<i>Salmo gairdneri</i>)

Abstract

The ontogeny of the stratum granulosum within the small intestine of the rainbow trout (Salmo gairdneri) was related to the chronological age of the animal. The component granule cells were first seen many weeks after the development of the collagenous stratum compactum. It is therefore concluded that the granule cells do not perform a critical role in stratum compactum formation. In addition, it is proposed that the stratum granulosum develops because of resistance of the stratum compactum to cellular penetration.