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Sperm Velocity (sperm + velocity)
Selected AbstractsThe influence of ovarian fluid on Solea senegalensis sperm motilityJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2010P. Diogo Summary The role of ovarian fluid in fertilization has been neglected, particularly in marine species. The aim of this work was therefore to assess the influence of ovarian fluid (OF) as a potential contributor factor to sperm motility in Solea senegalensis. The specificity of interactions between sperm and ovarian fluid was analyzed using homologous and heterelogous ovarian fluid. Additional tests tried to identify the most useful concentration for improving sperm motility throughout the activation process. Ovarian fluid solutions were diluted in artificial seawater (SW) (v:v) 0 : 100, 25 : 75, 50 : 50, 75 : 25 and 100 : 0 (OF:SW). Pure ovarian fluid solutions (100%) did not promote sperm motility by themselves since they lack the osmolarity needed to trigger sperm motility. With 75% of ovarian fluid the activation solution promoted a deficient activation and the best concentrations used were 25 and 50%. The presence of ovarian fluid affected significantly total motility (TM) and progressive motility (PM) in the last seconds post activation. Progressive motility was higher at 45 s for homologous 25% OF (20.4%) than control (9.4%). Homologous 25% OF increased significantly TM and PM at 60 s post activation (32.0 and 10.5%, respectively) when compared to control (15.8 and 1.7%, respectively). Sperm velocity showed significant differences in the presence of ovarian fluid since early seconds post activation. Our data revealed an enhancement of sperm motility with ovarian fluid at low concentrations in the activation solution. There seems to be a high degree of specificity of ovarian fluid-sperm interaction since heterologous fluid had a lower performance enhancing sperm motility than homologous fluid. Our results indicated a possible important female contribution to sperm motility enhancement during the fertilization process in S. senegalensis. [source] Sperm velocity in an Alpine whitefish: effects of age, size, condition, fluctuating asymmetry and gonad abnormalitiesJOURNAL OF FISH BIOLOGY, Issue 3 2007D. Urbach The relationship between sperm velocity and individual age, size, body condition and fluctuating asymmetry was investigated in Alpine whitefish Coregonus fatioi. The fish analysed belonged to one among several sympatric whitefish populations of Lake Thun, Switzerland, which are characterized by a high prevalence of gonad alterations. Therefore, sperm velocity data were also tested for a link between gonad deformation and sperm swimming speed. Sperm velocity was significantly lower in larger-grown individuals and in individuals of higher body condition. As expected, sperm velocity was higher in males with higher levels of fluctuating asymmetry, but it did not significantly vary with male age. Moreover, variation in sperm velocity was found to be significantly higher in individuals showing some types of gonad alterations but it did not significantly correlate with the presence of other types of alterations. [source] SPERM MORPHOLOGY AND VELOCITY ARE GENETICALLY CODETERMINED IN THE ZEBRA FINCHEVOLUTION, Issue 10 2009Jim Mossman Sperm morphology (size and shape) and sperm velocity are both positively associated with fertilization success, and are expected to be under strong selection. Until recently, evidence for a link between sperm morphology and velocity was lacking, but recent comparative studies have shown that species with high levels of sperm competition have evolved long and fast sperm. It is therefore surprising that evidence for a phenotypic or genetic relationship between length and velocity within species is equivocal, even though sperm competition is played out in the intraspecific arena. Here, we first show that sperm velocity is positively phenotypically correlated with measures of sperm length in the zebra finch Taeniopygia guttata. Second, by using the quantitative genetic "animal model" on a dataset from a multigenerational-pedigreed population, we show that sperm velocity is heritable, and positively genetically correlated to a number of heritable components of sperm length. Therefore, selection for faster sperm will simultaneously lead to the evolution of longer sperm (and vice versa). Our results provide, for the first time, a clear phenotypic and genetic link between sperm length and velocity, which has broad implications for understanding how recently described macroevolutionary patterns in sperm traits have evolved. [source] Sperm design and function in the redside dace Clinostomus elongatusJOURNAL OF FISH BIOLOGY, Issue 4 2009T. E. Pitcher A study was undertaken to examine sperm morphometry in relation to sperm velocity and sperm longevity in the redside dace Clinostomus elongatus. There was significant between-male variance in sperm size and shape metrics (total sperm length, sperm head length, flagellum length and sperm head length to width ratio) and positive relationships were found between these morphometrics and sperm velocity. There were no significant relationships found between sperm morphometry and sperm longevity, nor was there a trade-off between sperm velocity and sperm longevity. [source] Sperm velocity in an Alpine whitefish: effects of age, size, condition, fluctuating asymmetry and gonad abnormalitiesJOURNAL OF FISH BIOLOGY, Issue 3 2007D. Urbach The relationship between sperm velocity and individual age, size, body condition and fluctuating asymmetry was investigated in Alpine whitefish Coregonus fatioi. The fish analysed belonged to one among several sympatric whitefish populations of Lake Thun, Switzerland, which are characterized by a high prevalence of gonad alterations. Therefore, sperm velocity data were also tested for a link between gonad deformation and sperm swimming speed. Sperm velocity was significantly lower in larger-grown individuals and in individuals of higher body condition. As expected, sperm velocity was higher in males with higher levels of fluctuating asymmetry, but it did not significantly vary with male age. Moreover, variation in sperm velocity was found to be significantly higher in individuals showing some types of gonad alterations but it did not significantly correlate with the presence of other types of alterations. [source] Effects of Short-term Hyper- and Hypoprolactinaemia on Hormones of the Pituitary, Gonad and -Thyroid Axis and on Semen Quality in Male BeaglesREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009MB Koivisto Contents Effects of a short-term hyper- and hypoprolactinaemia on serum concentrations of LH, testosterone and semen quality in six male Beagles were investigated. Blood samples were collected at 3-day intervals for 12 weeks. The time span was divided into five 3-week periods: pre-treatment, metoclopramide (MCP) treatment (0.2 mg/kg orally three times daily), cabergoline (CAB) treatment (5 ,g/kg orally once daily), post-treatment 1 and post-treatment 2. In the latter, only semen characteristics were evaluated. Semen parameters were analyzed once per week during the whole 15-week investigation time. At the end of each period, the effects of a single intravenous injection of thyrotropin-releasing hormone (TRH; 10 ,g/kg) on the secretion of prolactin (PRL), LH, testosterone, thyroid-stimulating hormone and thyroxine (T4) were investigated. Pre-treatment serum PRL concentration increased under MCP (p < 0.05), followed by a decrease under CAB administration (p < 0.05). Luteinizing hormone and testosterone concentrations were not affected. Except for straight-line sperm velocity, semen quality did not differ between collection periods. A single iv TRH injection induced a significant PRL increase at 20 min in all experimental periods except during CAB treatment. Luteinizing hormone and testosterone did not show clear TRH-related changes. Basic T4 levels were significantly reduced after CAB treatment (p < 0.05). The results of the present study demonstrate that MCP-induced short-term hyperprolactinaemia in male beagles does not seriously affect the hypothalamo-pituitary axis and semen quality. [source] |