OBJECTIVE To review the literature on the association between male age and semen quality (semen volume, concentration, motility, and morphology) and fertility status (pregnancy rate and time to pregnancy/subfecundity). METHOD(S) Review of English language-published research over the last 20 years from January 1, 1980, through December 31, 1999, using MEDLINE and Biosis databases. Studies with...

BACKGROUND Tobacco smoking is a public health issue and has been implicated in adverse reproductive outcomes including semen quality. Available data however provides conflicting findings. The objective of this study was to evaluate the effect of tobacco smoking on semen quality among men in Ghana. METHODS In this study, a total of 140 subjects were recruited, comprising 95 smokers and 45 non-...

OBJECTIVES To provide information of semen quality among normal young Japanese men and indicate the frequency of reduced semen quality. DESIGN Cross-sectional, coordinated studies of Japanese young men included from university areas. The men had to be 18-24 years, and both the man and his mother had to be born in Japan. Background information was obtained from questionnaires. Standardised and...

Background: One of the most conventional causes of male infertility is increasing age, which has significant effects on sperm physiology. In advanced ages, degenerative alterations in germinal epithelium, decreased number of Leydig cells, and their functions affect spermatogenesis through a decrease in testosterone level. So it is important to know whether advanced paternal age is associated wi...

OBJECTIVES To determine semen quality and reproductive hormone levels in young Faroese men. DESIGN Descriptive cross-sectional study of Faroese men compared with Danish men. SETTING Faroese one-centre study. PARTICIPANTS 481 men born from 1981 to 1987 and investigated from 2007 to 2010. OUTCOME MEASURES Sperm concentration, semen volume, total sperm count, sperm motility, sperm morpholo...

BACKGROUND Diabetes mellitus (DM) is increasing in men of reproductive age. Despite this, the prevalence of diabetes in men attending fertility clinics is largely unknown. Furthermore, studies examining the effects of DM on sperm fertility potential have been limited to conventional semen analysis. METHODS Conventional semen analysis (semen volume, sperm count, motility and morphology) was pe...

Prostaglandin F2α (PGF2α), oxytocin and gonadotropin releasing hormone (GnRH) have been used in bulls, rams, boars, stallions or rodents to increase sperm numbers in the ejaculate. Improving sperm quantity in the canine ejaculate would benefit all assisted reproductive techniques used in this species. The purpose of the present study was to evaluate the effects of PGF2α, oxytocin and GnRH on ca...

The objective of this experiment was to test a hypothesis that L-carnitine supplemented diet would improve semen characteristics in 6 adult crossbred AI boars (Hampshire × Pietrain). The control and the tested diet were identical except the tested period (8 weeks) when the diet was supplemented with 2 g of l-carnitine per boar per day. The semen was collected regularly weekly by a gloved-hand t...

this study was aimed to evaluate the effect of gnrh injection on semen ejaculate characteristics in awassi rams collected in breeding and non breeding seasons. the study was conducted in late summer to early autumn when breeding activity commences, and in winter during the non breeding season. twelve mature awassi rams were used in this study. animals were randomly allocated into two equal grou...

the present investigation aimed to conduct a genetic study of dairy cattle and buffalo bulls based on economic traits and their phenotypic correlation. the means of various economic traits in both the species are presented. cattle bulls reported a better libido score, flehmen response, requirement of mounting stimulus and semen volume, conception rate and expected predicted difference for milk ...