CIRCULATING CONCENTRATIONS OF ESTRADIOL, LUTEINIZING HORMONE, AND FOLLICLE-STIMULATING HORMONE DURING WAVES OF OVARIAN FOLLICULAR DEVELOPMENT IN PREPUBERTAL CATTLE

Authors: MELVIN, E - UNIV OF NEBRASKA, LINCOLN; LINDSEY, B - UNIV OF NEBRASKA, LINCOLN; QUINTAL-FRANCO, J - UNIV OF NEBRASKA, LINCOLN; ZANELLA, E - UNIV OF NEBRASKA, LINCOLN; FIKE, K - UNIV OF NEBRASKA, LINCOLN; Van Tassell, Curtis - Curt; KINDER, J - UNIV OF NEBRASKA, LINCOLN

Submitted to: Biology of Reproduction
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/22/1998
Publication Date: N/A
Citation: N/A

Interpretive Summary: Characteristics of ovarian follicular development and concentrations of estradiol, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in the blood were evaluated during synchronized follicular growth of cattle prior to puberty. No interactions were found between day after follicular aspiration and month of prepuberty for numbers of follicles of size 4 mm or less or >5 mm or concentrations of LH, FSH, and estradiol. The pattern of change in those variables after follicular aspiration was similar for each month of prepuberty. Interactions were found between day after follicular aspiration and month of prepuberty for frequency and amplitude of LH pulses and size of largest follicle. Endocrine changes were found to be related to follicular development after follicular aspiration throughout the peripubertal period. Knowledge of ovarian hormonal activity during sexual maturation is necessary for developing techniques for breeders to improve reproductive performance of cattle.

Technical Abstract: Objectives were to characterize changes in concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol-17 beta (estradiol) in the blood and populations of ovarian follicles of prepubertal cattle during waves of follicular development and to evaluate interactions between the day after follicular aspiration and the month of prepuberty for those variables. During each month before puberty, ovarian follicles of prepubertal cattle were aspirated to induce synchronous emergence of a wave of follicular development. Multiple regression was used to estimate hormonal variables and evaluate interactions for variables between day after follicular aspiration and month of prepuberty. No interactions were found between day after follicular aspiration and month of prepuberty for numbers of follicles of size 4 mm or less or >5 mm or concentrations of LH, FSH, and estradiol. The pattern of change in those variables after follicular aspiration was, therefore, similar for each month of prepuberty. Interactions were found between day after follicular aspiration and month of prepuberty for frequency and amplitude of LH pulses and size of largest follicle. Endocrine changes were found to be related to follicular development after follicular aspiration throughout the peripubertal period.