| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Dairy Science Department, University of Wisconsin, Madison 53706 and
2 Departments of Animal Science, and Fisheries & Wildlife, Michigan State University, East Lansing, 48824
Corresponding author: M. C. Wiltbank; e-mail: wiltbank{at}calshp.cals.wisc.edu.
Ovarian function was compared between nulliparous heifers (n = 29; 10 to 16 mo old) and lactating Holstein cows (n = 31; 55.9 ± 3.5 d postpartum). Follicular dynamics, corpus luteum growth, and regression, and serum steroid concentrations were evaluated through ultrasonography and daily blood sampling. Most heifers (27 of 29) but only 14 of 31 cows had typical spontaneous estrous cycles after cycles were initiated. Twelve cows had atypical cycles, and 5 became anovulatory during the study. The 12 cows with atypical estrous cycles had low serum estradiol after luteolysis and failed to ovulate the dominant follicle present at luteolysis. Heifers and cows with typical cycles were compared directly. Interovulatory intervals were similar between heifers (22.0 ± 0.4 d) and cows (22.9 ± 0.7 d). Those animals had estrous cycles with either 2 (15 heifers; 11 cows), 3 (9 heifers; 2 cows), or 4 follicular waves (3 heifers; 1 cow). Cows ovulated later after luteolysis than heifers (5.2 ± 0.2 vs. 4.6 ± 0.1 d, respectively), and had more multiple ovulations (17.9 vs. 1.9%). Maximal serum estradiol concentration preceding ovulation was lower in cows than in heifers (7.9 ± 0.8 vs. 11.3 ± 0.6 pg/mL) even though ovulatory follicles were larger in cows (16.8 ± 0.5 vs. 14.9 ± 0.2 mm). Similarly, maximal serum progesterone concentration was lower for cows (5.6 ± 0.5 vs. 7.3 ± 0.4 ng/mL), whereas maximal volume of luteal tissue was larger for cows than heifers (11,120 ± 678 vs. 7303 ± 308 mm3). Thus, higher incidence of reproductive anomalies in lactating cows, such as low conception rate, ovulation failure, delayed ovulation, and multiple ovulations, may be due to lower circulating steroid concentrations in spite of larger ovulatory follicles and luteal structures.
Key Words: estrous cycle • ovary • estradiol • progesterone
Abbreviation key: CL = corpus luteum or corpora lutea, CR = conception rate, E2 = estradiol, P4 = progesterone
This article has been cited by other articles:
|
|
 |
|
  J. S. Stevenson, D. E. Tenhouse, R. L. Krisher, G. C. Lamb, J. E. Larson, C. R. Dahlen, J. R. Pursley, N. M. Bello, P. M. Fricke, M. C. Wiltbank, et al. Detection of Anovulation by Heatmount Detectors and Transrectal Ultrasonography Before Treatment with Progesterone in a Timed Insemination Protocol J Dairy Sci, July 1, 2008; 91(7): 2901 - 2915. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. H. Souza, A. Gumen, E. P. B. Silva, A. P. Cunha, J. N. Guenther, C. M. Peto, D. Z. Caraviello, and M. C. Wiltbank Supplementation with Estradiol-17{beta} Before the Last Gonadotropin-Releasing Hormone Injection of the Ovsynch Protocol in Lactating Dairy Cows J Dairy Sci, October 1, 2007; 90(10): 4623 - 4634. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Q. Li, F. Jimenez-Krassel, A. Bettegowda, J. J Ireland, and G. W Smith Evidence that the preovulatory rise in intrafollicular progesterone may not be required for ovulation in cattle J. Endocrinol., March 1, 2007; 192(3): 473 - 483. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S. Stevenson, M. A. Portaluppi, and D. E. Tenhouse Ovarian Traits After Gonadotropin-Releasing Hormone-Induced Ovulation and Subsequent Delay of Induced Luteolysis in an Ovsynch Protocol J Dairy Sci, March 1, 2007; 90(3): 1281 - 1288. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Rivera, R. A. Sterry, and P. M. Fricke Presynchronization with gonadotropin-releasing hormone does not improve fertility in holstein heifers. J Dairy Sci, October 1, 2006; 89(10): 3810 - 3816. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. M. Bello, J. P. Steibel, and J. R. Pursley Optimizing ovulation to first GnRH improved outcomes to each hormonal injection of ovsynch in lactating dairy cows. J Dairy Sci, September 1, 2006; 89(9): 3413 - 3424. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Lopez, D. Z. Caraviello, L. D. Satter, P. M. Fricke, and M. C. Wiltbank Relationship Between Level of Milk Production and Multiple Ovulations in Lactating Dairy Cows J Dairy Sci, August 1, 2005; 88(8): 2783 - 2793. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. S. Burns, F. Jimenez-Krassel, J. L.H. Ireland, P. G. Knight, and J. J. Ireland Numbers of Antral Follicles During Follicular Waves in Cattle: Evidence for High Variation Among Animals, Very High Repeatability in Individuals, and an Inverse Association with Serum Follicle-Stimulating Hormone Concentrations Biol Reprod, July 1, 2005; 73(1): 54 - 62. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Gumen and M. C Wiltbank Follicular cysts occur after a normal estradiol-induced GnRH/LH surge if the corpus hemorrhagicum is removed Reproduction, June 1, 2005; 129(6): 737 - 745. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Rivera, H. Lopez, and P. M. Fricke Fertility of Holstein Dairy Heifers after Synchronization of Ovulation and Timed AI or AI after Removed Tail Chalk J Dairy Sci, July 1, 2004; 87(7): 2051 - 2061. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
