Background: Obesity and raised body mass index (BMI) is a major risk factor for several diseases such as cardiovascular disease, type 2 diabetes, as well as gynecological problems. In recent years, some studies have associated the BMI with reproductive parameters in men, showing that increased BMI is related to poor semen quality, decreased sperm concentration, decreased and normal-motile sperm...

BACKGROUND Post-copulatory sexual selection has been shown to shape morphology of male gametes. Both directional and stabilizing selection on sperm phenotype have been documented in vertebrates in response to sexual promiscuity. METHODOLOGY Here we investigated the degree of variance in apical hook length and tail length in six taxa of murine rodents. CONCLUSIONS Tail sperm length and apica...

Theories regarding the role of sexual selection on the evolution of sperm traits are based on an association between pre-copulatory (e.g. female preference) and post-copulatory (e.g. ejaculate quality) male reproductive traits. In tests of these hypotheses, sperm morphology has rarely been used, despite its high heritability and intra-individual consistency. We found evidence of selection for l...

Background: Many sperm characteristics including, motility and morphology are important for normal spermatozoa- oocyte intraction. These features may be altered during vitrification. Motile sperm organelle morphology examination (MSOME) is an unstained real time high magnification technique that analysis viable sperm morphology instantly. This study aimed to investigate the influence of vitrifi...

BACKGROUND The aim of this study was to determine if only sperm with double stranded DNA could bind to the human zona pellucida (ZP). METHODS Sperm samples from 124 infertile men with a range of semen abnormalities were studied. Oocytes that had failed to fertilize in IVF or ICSI were used for the sperm-ZP binding test. A group of four oocytes were incubated for 2 h with 2 x 10(6)/ml motile s...

BACKGROUND Previous researches about the effect of smoking on semen quality are contradictory, and the mechanism behind the harmful effect of smoking on semen quality still remains unclear until today. OBJECTIVE The objectives of this study are evaluation of the relationship between smoking and fertility, investigation of the effects of cigarette smoking on sperm parameters and detection of p...

We investigated how sperm morphology varies across 16 species of shorebirds in the Scolopacidae, Charadriidae, and Jacanidae. Sperm were significantly longer in nonmonogamous than in socially monogamous species. Nonmonogamous species also I Received 27 January 1999. Accepted 22 June 1999. 2Current address: Department of Zoology, Private Bag 4800, University of Canterbury, Christchurch, New Zeal...

The aim of the present study was to evaluate the effects of sodium fluoride (NaF) on the male reproductive system. Adult male rats were exposed to NaF in drinking water for 30 days at three concentrations: 1.54 (control, tap water), 50 and 100 ppm. Body and organ weights, daily sperm production, sperm number and morphology were investigated. No difference was observed on the sperm number and mo...