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 Swierstra, E. E. Search for Related Content PubMed PubMed Citation Articles by Swierstra, E. E.

A Comparison of Regular Ejaculation with Sexual Rest on Semen Characteristics and Reproductive Organ Weights in Young Boars

Agriculture Canada, Research Station, Brandon, Manitoba R7A 5Z7

Abstract

Two experiments were conducted to determine the effects of regular semen collections at 96- and 72-hr. intervals, starting when the boars were 198 and 206 days old, respectively, on subsequent semen characteristics and development of the reproductive organs. In the first experiment, 44 boars averaging 198 days (SE ± 1) of age and weighing 105 kg (SE ± 1) were assigned to five groups differing in semen quality. The different groups were placed on a regular 96-hr, semen collection schedule at 198, 235 and 271 days of age, and the experiment terminated when the boars were 328 days old. Semen characteristics of boars ejaculated since they were 198 days old were similar to semen characteristics of boars sexually rested during the first part of the experiment. Furthermore, semen quality improved more rapidly with time in boars that had initially low quality semen than in boars that had initially high quality semen. Thus, boars that had low numbers of total and motile sperm per ejaculate at 6.5 months of age, did not necessarily have low numbers of total and motile sperm per ejaculate when they reached 10 months of age.

In the second experiment, 48 boars averaging 206 days (SE ± 1) of age and weighing 106 kg (SE ± 1) were assigned to three groups so that the groups were similar as to age, body weight and mean number of motile sperm in two ejaculates. The groups were placed on a regular 72-hr. semen collection schedule at 206, 245 and 281 days of age, and the experiment terminated when the boars were 315 days old. Semen characteristics of boars sexually rested until they reached 245 and 281 days of age were similar to semen characteristics of boars ejaculated since they were 206 days old. Age effects on semen characteristics were most pronounced when boars aged from 6.5 to 8.5 months. The development of the testes and accessory sex glands was not significantly influenced by regular 96- or 72-hr, ejaculation starting when the boars were 6.5 to 6.8 months of age.