HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Rabb, M. H. Articles by Hehnke, K. E. Search for Related Content PubMed PubMed Citation Articles by Rabb, M. H. Articles by Hehnke, K. E.

Effects of Sexual Stimulation, with and without Ejaculation, on Serum Concentrations of LH, FSH, Testosterone, Cortisol and Prolactin in Stallions¹

Louisiana State University Agricultural Center³, Baton Rouge 70803

Abstract

Six lighthorse stallions with previous sexual experience were used to determine the short-term effects of sexual stimulation (SS; 5 min exposure to an estrous mare), SS plus ejaculation (SSE), and no stimulation (control) on serum concentrations of LH, FSH, testosterone, Cortisol and prolactin. Stallions received one treatment per day on d 1,4 and 7. Treatments were assigned such that each stallion 1) received each treatment once and 2) experienced a unique sequence of treatments. Neither SS nor SSE had any consistent effects on LH or FSH concentrations. Testosterone concentrations during control bleedings increased (P < .05) with time. This increase was suppressed (P < .05) by both SS and SSE. Cortisol concentrations increased (P < .05) immediately after SS and SSE. Cortisol concentrations also tended to increase during the control bleedings, but only in stallions that previously had been exposed to SS or SSE. Prolactin concentrations increased (P < .05) immediately after SS and SSE and tended to rise during control bleedings in stallions previously exposed to SS or SSE. We conclude that 1) prolactin and Cortisol were secreted rapidly in response to SS and SSE, 2) the rise in Cortisol concentrations likely suppressed testosterone secretion within the next hour, and 3) stallions appeared to associate the distant sounds of other stallions with their own previous exposure to SS and SSE, resulting in a Cortisol response (and perhaps a prolactin response) even in the absence of direct stimulation.

¹ Approved for publication by the Director of the Louisiana Agric. Exp. Sta. as manuscript no. 88-11-3012.

² Send reprint requests to D. L. Thompson, Jr., Anim. Sci. Dept., Louisiana State Univ., Baton Rouge 70803.

³ Anim. Sci. Dept., Louisiana Agric. Exp. Sta.