An Ultrastructural Study of Mitochondria of Mammary Secretory Cells in Rabbits During Lactation and Regression Stages.

Svätoslav Hluchý


The aim of this study was ultrastructural study of mitochondria in epithelial secretory cells in mammary glands of rabbits during lactation and regression stages. Our results using conventional transmission electron microscopy have shown that the mitochondria are relatively changed during the various mammary gland development stages.We found that the average relative volume of mitochondria achieves 12.530 ± 3.127 % of  cytoplasm volume in the stage of lactation. During regression mitochondrial relative volume decreased to 3.583 ± 1.626 % of the cytoplasm. This difference compared to lactation is statistically significant (P 0.05). Relative surface of mitochondria during lactation reaches 2.092 ± 0.550 μm2 / μm3 of cytoplasm. We found a decrease of relative surface of mitochondria to 0.556 ± 0.184 μ m 2 / μm3 of cytoplasm during regression stage. After the end of lactation, we found that the average size of mitochondria is 0.376 ± 0.074 µm. Differences in the average size during lactation and regression are statistically significant, suggesting that mitochondria retain their size, regardless of the physiological state of activity of the mammary gland. Abundance of mitochondria during lactation is 49.34 ± 15.2 mitochondria per 100 μm3 of cytoplasm. Abundance of mitochondria positively correlated with abundance of all cytoplasmic structures except the abundance of fat droplets, where we found a very strong negative correlation. We found 10.70 ± 7.0 mitochondria per 100 μm3 of cytoplasm after the end of lactation. Average volume of individual mitochondria reach 0.196 ± 0.008 μm3.  Average volume of individual mitochondria reaches 0,239 ± 0,142 μm3 during regression. Although there is a certain tendency to increase in volume, which is also linked with an average size of mitochondria, the difference compared with the period of lactation is not statistically significant.


mitochondria, secretory epithelial cells, mammary glands, electron microscopy

Full Text:



Ahlem A., Samira M., Ali el H., Pierre G., Leila T.. Ultrastructural study of the intracellular behavior of four mineral elements in the lactating mammary gland cells: study using conventional transmission electron microscopy.Microsc Res Tech., 2008;71(12):849-55.

Bózner A., Baláz V., Dostál J., Szigetiová A.. Electron microscopy morphometric analysis of the effect of immobilization stress on the structure of the myocardium in rats belonging to 2 age groups. Cesk Patol., 1984, 20(3):146-50.

Hadsell DL., Olea W., Wei J., Fiorotto ML., Matsunami RK., Engler DA., Collier RJ. Developmental regulation of mitochondrial biogenesis and function in the mouse mammary gland during a prolonged lactation cycle. Physiol Genomics., 2011,43(6):271-85.

Hluchý,S.: Ultraštruktúra buniek mliečnych žliaz králičice a ošípanej.Habilitačná práca , SPU Nitra, 1996: 156, 73 grafov, 28 tab., 37 fotogr.

Hollman,K.H. Cytology and fine Structure of the Mammary Gland. In.: Ed. Larson,B.L.-Smith,V.R.: Lactation. A Comprehensive Treatise I: Mammary Gland / Development and Maintenance. Academic Press, New York,1974: 3-95.

.Jimenez,L.,Rua,C.,Muňiz,E.,.Garcia,P.Alveolar epithelial cells of the mammary gland of Lactating Myotis myotis: An Ultrastructural Study. Z. mikrosk.-anat. Forsch.,Leipzig 98,3,1984: 465-477.

Kanari Y, Noguchi M., Kaminaga K., Sakamoto Y., Yokoya A. Live-cell imaging study of mitochondrial morphology in mammalian cells irradiated. J Radiat Res. 2014 :129-i130.

Lee C.S.,Morgan G.,Wooding F.B.P.: Mitochondria and mitochondria-tonofilament- desmosomal associations in the mammary gland secretory epithelium of Lactating cows. J.Cell Sci. 38,1979: 125-135.

Mráz P..Polónyi J.: Metódy elektrónovej mikroskopie živočíšnych tkanív. Veda Vyd. SAV, Bratislava 1988, :309.

Pichaud N., Garratt M., Ballard JW., Brooks RC. Physiological adaptations to reproduction. II. Mitochondrial adjustments in livers of lactating mice. J Exp Biol. 2013,1;216: 2889-95.

PULLEY,L.T.: Ultrastructural and Histochemical demonstration of myoepithelium in the normal canine mammary gland. Am.J.Vet.Res. 34,12,1973:1505-1512.

Perkins GA., Ellisman MH., Fox DA.: Three-dimensional analysis of mouse rod and cone mitochondrial cristae architecture: bioenergetic and functional implications. Mol Vis. 2003 11;9:60-73.

Qu B., Jiang Y., Zhao F., Xiao J., Li QZ. Changes of endoplasmic reticulum and mitochondria in mammary epithelial cells during mammogenesis in Chinese Holstein dairy cows. Acta Histochem. 2012;114(5):448-53.

Reid,I.M.,Harrison,R.D.,Anderson,J.C.: Experimental staphylococcal mastitis in the mouse. A morphometric study of early changes in mammary gland structure. J.Comp.Path. 86,1976 :329-336.

Rosano TG., Lee SK., Jones DH.:Developmental changes in mitochondria during the transition into lactation in the mouse mammary gland. II. Membrane marker enzymes and membrane ultrastructure.J Cell Biol. 1976 Jun;69(3):581-8.

Uhrín V.,Kliment J.: Submikroskopická stavba mliečnej žľazy kravy počas laktácie. Živočíšna výroba, 27,1982, 7:503-513.


  • There are currently no refbacks.

Copyright (c)

Scientific Papers Animal Science and Biotechnologies publish open access articles under the terms of the Creative Commons Attribution 4.0 Licence (read full legal code).


ISSN print 1841 - 9364
ISSN online 2344 - 4576
ISSN-L  1841 - 9364
(former ISSN 1221-5287, E-ISSN 1841-9364)

PAPER ACCESS: Full text articles available for free
FREQUENCY: Semiannual

Banat´s University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara
Bioengineering Faculty of Animal Resources
300645, Timişoara, Calea Aradului 119, Romania

E-mail: spasb [at]
Phone: +40-256-277160, Fax.: +40-256-277110