|
|
||||||||
Biology of Reproduction, Vol 32, 1181-1190, Copyright © 1985 by Society for the Study of Reproduction
ARTICLES |
L Johnson
Seasonal variation in number of spermatogonia and germ cell degeneration was evaluated to determine which mechanism might explain seasonal differences in daily sperm production per testis (DSP/testis) or per g parenchyma (DSP/g) in stallions. Comparing 28 adult stallions (4 to 20 yr old) in each of the nonbreeding (December-January) and breeding (June-July) seasons, the population of type A spermatogonia was more than two times greater (P less than 0.01) in the breeding season. While the number of type B spermatogonia also was elevated (P less than 0.01) in the breeding season, the number of type B spermatogonia/type A spermatogonium was similar (P greater than 0.05) between seasons. Daily sperm production/testis based on each cell type from type B spermatogonia to spermatids with elongated nuclei was lower (P less than 0.01) in the nonbreeding season. Based on DSP/g, there was significant degeneration during the meiotic divisions in the nonbreeding season. However, this reduction in potential spermatozoan production was not significant (P greater than 0.05) when considering DSP/testis. Significant germ cell degeneration also occurred in the breeding season between type B spermatogonia and primary spermatocytes. However, the type A spermatogonial population was sufficiently elevated to override this degeneration and to explain elevated production of sperm in the breeding season of stallions.
This article has been cited by other articles:
![]() |
P. Froment, C. Staub, S. Hembert, C. Pisselet, M. Magistrini, B. Delaleu, D. Seurin, J. E. Levine, L. Johnson, M. Binoux, et al. Reproductive Abnormalities in Human Insulin-Like Growth Factor-Binding Protein-1 Transgenic Male Mice Endocrinology, April 1, 2004; 145(4): 2080 - 2091. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Sipahutar, P. Sourdaine, S. Moslemi, B. Plainfosse, and G.-E. Seralini Immunolocalization of Aromatase in Stallion Leydig Cells and Seminiferous Tubules J. Histochem. Cytochem., March 1, 2003; 51(3): 311 - 318. [Abstract] [Full Text] [PDF] |
||||
![]() |
D.D. Lunstra, T.H. Wise, and J.J. Ford Sertoli Cells in the Boar Testis: Changes During Development and Compensatory Hypertrophy after Hemicastration at Different Ages Biol Reprod, January 1, 2003; 68(1): 140 - 150. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Yazawa, T. Yamamoto, and S.-I. Abe Prolactin Induces Apoptosis in the Penultimate Spermatogonial Stage of the Testes in Japanese Red-Bellied Newt (Cynops pyrrhogaster) Endocrinology, June 1, 2000; 141(6): 2027 - 2032. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |