摘要
the aim of the present study was to sit morphological bases for the inmumocitochemical and hybridazion in situ study of the presence and distribution of estrogen and progesterone receptors in sheep of different prolificity and in different nutrition plane, centering our interest in the endometrium for its relevance in the reproductive mechanisms. we used sheep prepuberal romney mash of high prolificity (n=2) and araucanian of standard prolificity(n=2) immediately after slaughter uterine tissue was taken for histhological study from uteri , oviduct and ovary. cross sections were stained with hematoxilina-eosina, van giesson, arteta and periodic acid of schiff (p.a.s.). the results showed in both races a good endometrial development, with caruncular and glandular intercaruncular glandular areas well defined, the later necessary for embryo implantation and growth the numerous, tubular, coiled, glands, extend to the miometrium. no significant histological differences were observed between both races neither morphological changes between days 93 to 117 of post natal life ,being their aspect similar to the endometrium of mature sheep.