REGRESSIVE CHANGES OF MAMMARY-GLANDS OF R ABBITS AFTER FINISHING LACTATION

This paper deals with the description and quantification of microscopi c structure and the regressive changes of mammary glands of New Zealan d's White rabbits after finishing lactation. The samples of mammary gl and tissue were taken after killing the animals for their processing b y histological and histochemical methods. The subjective and quantitat ive morphometric methods were used for the evaluation of the samples. The connective tissue becomes the most substantial component of the ud ders of rabbits during this stage. The relative volume of the connecti ve tissue was increased up to 83.73 +/- 8.87% but out of it the collag enous tissue forms 75.45 +/- 15.94% and the thin tissue 8.28 +/- 12.61 % from this volume. The adipose tissue represents only 3.22 +/- 7.01%. At the same time, relative volume of the glandular parenchyma is decr eased up to 13.05 +/- 9.17% and the relative volume of epithelium lowe rs up to 8.27 +/- 5.90% and the relative volume of lumen up to 4.78 +/ - 4.04%. The average dimensions and the amount of lobules, alveoli and ducts of the glandular parenchyma were decreased too. The average dim ensions of alveoli were found to be 28.89 +/- 6.85 mu m. One cm(3) of the mammary gland tissue consisted of 70 287.22 tubuloalveolar structu res. The volumes of each alveolus wall (epithelium) in relation to the cavity (lumen) and nucleocytoplasmic ratio were investigated. The cor relations between all structural parts of mammary glands were calculat ed.