|
|
||||||||
Department of Animal Sciences and Department of Veterinary Clinical Medicine, University of Illinois, Urbana 61801
ABSTRACT
Bovine mammary tissue was collected by surgical biopsy at intervals during involution for histological and ultrastructural observation. In lactating tissue (d 0 of involution, collected 8 h after the final milking), alveolar epithelial cells had marked ultrastructural evidence of lactation, including protein-containing secretory vesicles, lipid droplets, extensive rough endoplasmic reticulum, and numerous mitochondria. By d 2 of involution, alveolar epithelial cells contained large vacuoles apparently formed by coalescing of protein-containing secretory vesicles and lipid droplets. Large vacuoles were observed in epithelial cells until about the 3rd wk of involution. By d 2 of involution, the Golgi apparatus generally was not apparent. Rough endoplasmic reticulum and mitochondria were observed throughout the period studied, although in reduced amounts compared with their presence in lactating tissue. A marked increase in lysosomal or cytosegresomal structures in epithelial cells was not observed. There was no evidence of extensive sloughing of epithelial cells from the basement membrane. There was a progressive increase in the interalveolar area and a concurrent decrease in the alveolar luminal area as involution progressed. Ultrastructural examination showed that alveolar epithelial cells at d 21 and 30 of involution appear to be functionally active but not secreting milk components.
This article has been cited by other articles:
![]() |
K. Singh, S. R. Davis, J. M. Dobson, A. J. Molenaar, T. T. Wheeler, C. G. Prosser, V. C. Farr, K. Oden, K. M. Swanson, C. V. C. Phyn, et al. cDNA Microarray Analysis Reveals that Antioxidant and Immune Genes Are Upregulated During Involution of the Bovine Mammary Gland J Dairy Sci, June 1, 2008; 91(6): 2236 - 2246. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. E. Dallard, V. Ruffino, S. Heffel, and L. F. Calvinho Effect of a Biological Response Modifier on Expression of Growth Factors and Cellular Proliferation at Drying Off J Dairy Sci, May 1, 2007; 90(5): 2229 - 2240. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. L. Annen, A. C. Fitzgerald, P. C. Gentry, M. A. McGuire, A. V. Capuco, L. H. Baumgard, and R. J. Collier Effect of Continuous Milking and Bovine Somatotropin Supplementation on Mammary Epithelial Cell Turnover J Dairy Sci, January 1, 2007; 90(1): 165 - 183. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |