the main purpose of this study was to evaluate the influence of the photoperiod on the seminal traits of crossbreed wool-producing rams throughout on year period. for the effect of photoperiod two periods were considered: decreasing daylight length (summer and autumn) and increasing daylight length (winter and spring). for the study 5 baluchi × moghani (bl×mg) and 5 arkharmerino × moghani (am×m...

the objective of this study was to evaluate the importance of environmental and genetic factors affecting semen quality; sperm volume (sv), sperm concentration (spco), total sperm (ts), fresh sperm motility (fsm), total fresh motile sperm (tfms), post thaw sperm motility (ptsm), total post thaw motile sperm (tptms), number of produced payout (npp), number of fresh motile sperm in each milt ejac...

There are contrary reports of association of lead and cadmium with the decline in semen quality. This study evaluates whether seminal lead (Pb) and cadmium (Cd) at environmental concentration are associated with altered semen quality. We conducted a study of healthy fertile and infertile men 20-43 years of age attending the Andrology Laboratory of Reproductive Biology Department for semen analy...

semen from six adult male black bengal goats (capra hircus) was collected to compare the fresh and frozen-thawed semen quality and investigate its relationship with the fertility. each collected samples was divided into two parts: one part of semen was used as fresh and another part was filled into 0.50 ml straws, sealed, cooled (5 ˚c) and equilibrated for freezing.in both cases, semen was dilu...

Semen characteristics were studied among 200 fertile Pakistani men aged 24 to 48 years. Each subject had fathered at least two children. The mean +/- SD values of volume, sperm density, motility percentage, grade of motility and percentage of oval sperms were 3.11 +/- 1.2 ml, 58.21 +/- 26.41 million/ml, 61.2 +/- 21.3%, 3.01 +/- 0.94 and 70.2 +/- 15.36% respectively. There was no deteriorating e...

decades (20–50 years) and concerning thousands of individuals.3 Although interesting and alarming, observed changes during a 4-year observation of 1808 men do not allow a formal conclusion, especially as confounding factors such as tobacco, alcohol consumption or body mass index were not considered. Authors suggested that environmental, psychosocial and climate factors may explain the non optim...

OBJECTIVES Possible relationship between semen quality (semen volume, sperm concentration and sperm motility) and parabens exposure was investigated in male partners of couples who visited a gynecology clinic in Tokyo for infertility consultation (n = 42, 36.8 ± 5.4 years). METHODS Semen parameters were measured according to WHO guideline at the clinic, and urinary methyl- (MP), ethyl- (EP), ...

Although geographic variation in semen quality has been reported, this is the first study in the United States to compare semen quality among study centers using standardized methods and strict quality control. We evaluated semen specimens from partners of 512 pregnant women recruited through prenatal clinics in four U.S. cities during 1999-2001; 91% of men provided two specimens. Sperm concent...

Few empirical data exist on the characteristics of subjects who provide semen specimens in epidemiologic studies. The objective of this investigation was to determine participation rates and potential biases in a contemporary study of human semen quality. Subjects (n = 268) are a subset of the Child Health and Development Studies. Their mothers enrolled between 1960 and 1963 during pregnancy. A...

The aim of the present study was to assess variability in the evaluation of human sperm concentration, motility and vitality. Technicians and biologists from 10 teams involved in multicentre studies on semen quality attended the same laboratory, each team using its own methods and equipment to analyse the same semen samples. Inter-individual variability was assessed from 17 fresh semen samples ...