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Live Spermatozoa (live + spermatozoa)

Distribution by Scientific Domains

Life Sciences	50%

Selected Abstracts

The structure of the bursa copulatrix in virgin and mated snails, Helisoma duryi (Mollusca): role of acid phosphatase in reproduction

INVERTEBRATE BIOLOGY, Issue 1 2001
Eric Clelland
Abstract. The fine structure of the bursa copulatrix of the virgin snails has been compared with that of mated snails. One of the noticeable changes after mating is an increase in the number of the Golgi and the secretory vesicles. Since some of the vesicles react positively for acid phosphatase it is suggested that this enzyme activity increases following mating. The bursa lumen of the virgin snail contains gel-like materials devoid of spermatozoa, however, following mating, the lumen is full of semen containing live spermatozoa and bacteria. The source of bacteria in the lumen is not known. Acid phosphatase activity is significantly higher in the luminal content of mated snails than in the virgin snails. The activity is higher in the lumen than in the epithelial cells, suggesting that the enzyme is secreted into the lumen where it is utilized for extracellular degradation of spermatozoa. Following mating, the spermatozoa are motile in the lumen of the bursa for ,3,7 d, but become immobile and finally undergo extracellular digestion so that intact spermatozoa are not recognizable by day 10. The use of castrated snails in mating experiments suggest that individuals of Helisoma duryi reproduce by cross fertilization and that the bursa may act as the holding organ from where the spermatozoa are periodically transported to the carrefour over ,7 d. At day 10 following mating, however, autosperms appear in the hermaphroditic duct awaiting the next mating. [source]

Effect of exogenous DNA on bovine sperm functionality using the sperm mediated gene transfer (SMGT) technique

MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 8 2010
Sebastian Canovas
Sperm mediated gene transfer (SMGT) could provide the opportunity to carry out transgenesis on a mass scale using spermatozoa as vectors for exogenous DNA. However, the efficiency of sperm-mediated DNA transfer is still questionable, and the mode of transmission to the egg has not yet been well understood. Our aim was to investigate the capacity of bovine spermatozoa to carry exogenous DNA and its relationship to sperm functionality. We studied these parameters using flow cytometry to measure viability (necrosis and apoptosis) and capacitation status, computer-assisted semen analysis (CASA) to measure motility parameters and in vitro fertilization (IVF) to assess fertilizing capacity. Furthermore, we studied the effect of capacitation status on interaction with exogenous DNA, and the role of heparin supplementation in this process. Bull spermatozoa showed a high capacity to bind DNA quickly and reached a maximum after 30,min, with approximately half of the DNA-bound spermatozoa being viable. Incubation with exogenous DNA induced a decrease in sperm viability and motility and increased the proportion of apoptotic cells, but did not affect the cleavage rate in IVF assay. Heparin increased high-lipid disorder and the number of sperm with DNA bound (viable and dead). In conclusion, this study shows that live spermatozoa can bind exogenous DNA with a slight negative effect in some parameters of sperm function that in our opinion, would not drastically compromise fertility. Mol. Reprod. Dev. 77: 687,698, 2010. © 2010 Wiley-Liss, Inc. [source]

Assessment of Different Sperm Quality Parameters to Predict in vitro Fertility of Bulls

REPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2002
S Tanghe
Contents Frozen-thawed semen from six bulls with high (> 60%) and low (20,35%) in vitro fertility was used for studying the predictive value of simple sperm quality tests with respect to in vitro fertilization (IVF) outcome as assessed by pronucleus (PN) formation ability. Sperm quality parameters, such as sperm concentration, motility, progressive motility, live-dead sperm ratio, morphology, membrane integrity, mitochondrial activity and acrosomal status were analysed using both conventional and automatic techniques at three time points during the IVF process, namely after sperm thawing, Percoll differential gradient centrifugation and IVF. Associations between the sperm quality parameters before and after IVF, and PN formation ability were assessed by using linear regression analyses. The percentages of motility, progressive motility and normal morphology determined after sperm thawing, and the percentage of live spermatozoa assessed after Percoll preparation by using nigrosin-eosin (N-E) staining showed a good correlation with PN formation ability, but the regression parameters were borderline not significant. These parameters formed the most reliable basis for predicting IVF outcome. After IVF, the percentage of live spermatozoa determined by using N-E staining was the only sperm quality parameter showing a significant association with the PN formation ability of a given bull. This sperm quality test can be used as a non-invasive method to estimate the PN formation ability of oocytes which are further cultured to assess embryonic development. [source]

Sperm fertility of the subtropical freshwater streaked prochilod Prochilodus lineatus (Characiformes) improved after dilution and cold storage

AQUACULTURE RESEARCH, Issue 10 2010
Laura H Orfão
Abstract The aims of this study were to evaluate the efficiency of simple and complex extenders in prolonging the cold storage of sperm (Experiments 1 and 2) and to test the diluted-cooled sperm in the best extender with regard to sperm quality parameters (Experiment 3) in the streaked prochilod, Prochilodus lineatus. In all the experiments, aliquots of 0.3 mL of sperm were diluted 1:10 in extenders and stored at 4,6 °C. Sperm diluted in simple extenders (NaCl and glucose solutions) yielded 0,26% sperm motility, whereas sperm diluted in complex extenders (BTSÔ, M IIIÔ and AndrostarÔ) yielded 62,81% sperm motility on day 4 after cold storage. When AndrostarÔ was further investigated, the following was observed on day 4: 53% motility with 94 s of duration; 47% live spermatozoa; 26,61% fertility rate; and 22,60% hatching rate. The use of AndrostarÔ improves the sperm fertility of the streaked prochilod during a 4-day storage period and can therefore be used to facilitate artificial reproduction. [source]