Artificial insemination via cooled or frozen-shipped semen allows more mares to be bred to a single stallion, but not all stallions produce semen capable of withstanding the cooling and freezing procedures. Aurich et al. (1996) estimated that cooled or frozen-shipped semen achieves < 75% of the pregnancy rates achieved with fresh semen. Some factors affecting the fertility rates of thawed semen...

The chamois of Abruzzi (Rupicapra pyrenaica ornata) has been classified as endangered by the World Union for Conservation. The objective of this study was to analyze seasonal differences in the characteristics of various male reproductive organs and in semen quality. The study was conduced during 2004 in the reserve of Lama dei Peligni (Italy) on three chamois males aged between 2 and 5 years. ...

Sperm concentration, morphology, DNA condensation and nuclear protein pattern as well as sperm adenylate cyclase were evaluated in semen samples provided by 7 volunteers every 8 h for 2 days. During the observation period, sperm concentration and total sperm number decreased but began to return towards normal after a 3-day abstinence period. No increase in the proportion of immature sperm cells...

Sperm production is a crucial factor for the potential reproductive success of males in many species (Nakatsuru & Kramer, 1982). Especially under strong sperm competition, higher sperm numbers in the ejaculates are likely to increase a male’s chance of fertilization (Parker et al., 1996). But sperm production is limited by physiological constraints, e.g. by testis size, which often depends on t...

The aim of the study was to determine the effect of growth rate and lean meat content in Pietrain×Duroc and Duroc×Pietrain hybrid boars on their semen characteristics. On the basis of the results of performance testing carried out on the 180 day of life, the boars were divided into four groups according to their daily weight gain (I: 750–800 g; II: 801–850 g; III: 851–900 g; and IV: >900 g), an...

background: infertility is common among couples of child-bearing age and ap-proximately half of known causes of primary infertility are attributable to male factor. it is still unclear whether the injurious effects of cigarette smoking on sperm characteristics and infertility are due to nicotine. therefore, the present study investigated the effects of orally administered of nicotine on sperm c...

In many species, including the dog (Canis familiaris), semen analysis protocols has improved in recent years. In vitro assessment of semen quality provides important information; however, the ultimate parameter for determining semen quality is pregnancy outcome. The objective of the present study was to investigate the efficiency of in vitro sperm tests in predicting seminal quality in dogs by ...

HE characteristics of mutational damage recovered from spermatogonial cells Tare important for considerations of genetic risks from radiation. The genetic and cytological types of mutations recovered from spermatogonia determine the chances of genetic damage offered the ensuing populations. To study these characteristics, radiation studies were carried out in Drosophila where well defined genet...

The fertilizing ability of stallion semen was analyzed using fresh and frozen samples, obtained before (June-July) or during (October-November) the breeding season. Thirty ejaculates obtained from 4 stallions were used. The analysis comprises routine seminogram; ATP concentration (Comhaire et al., 1983); subjective and objective motility and sperm velocity (Makler, 1980). Freezing was done foll...

Theory predicts that males experiencing elevated levels of sperm competition will invest more in gonads and produce faster-swimming sperm. Although there is ample evidence in support of the first prediction, few studies have examined sperm swimming speed in relation to sperm competition. In this study, we tested these predictions from sperm competition theory by examining sperm characteristics ...