The spleen of a specially adapted mammal, the little hairy armadillo Chaetophractus vellerosus (Xenarthra, Dasypodidae). A light and electron microscopic study.

GALÍNDEZ, E.J.; ESTECONDO S.; CASANAVE E.B

INTERNATIONAL JOURNAL OF MORPHOLOGY

Univ de La Frontera (Sociedad Chil. de Anatomía)

Lugar: Temuco - Chile; Año: 2006 vol. 24 p. 339 - 348

0717-9367

SUMMARY: The spleen isa multifunctional organ. Its microarchitecture reflects so well the phylogenyas the adaptation to niche in each animal group and inclusive in each species. Armadillos,as ancient and isolated mammals, show a mixture of ancestral and modernstructures. In this work the microanatomy and cytology of the spleen of thelittle hairy armadillo Chaetophractus vellerosus was studied.The material was fixed and processed according to the typical methods for lightand electron microscopy. Results show a cumulative medium sized spleen with thetypical pulps. The white pulp is well developed but less defined than in otherarmadillos. The presence of follicular-dendritic-like cells and interdigitantdendritic-like cells, as well as clusters of immunocompetent cells agrees withan active immunological activity. The red pulp is a meshwork of circulatoryspaces and cells. The presence of splenic sinusoids is recognized for the firsttime in the genus. Hemopoietic tissue is less developed than in otherEuphractini. The microarchitecture and size of the spleen of C.vellerosus is discussed in a phylogenetic and adaptive context.