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1. Ram and bull spermatozoa suspended in a glucose-sodium chloride solution rapidly lose motility at relatively high dilutions. The substitution of chloride-free diluents does not alter the phenomenon. 2. The rapid immobilization of ram and bull spermatozoa due to high dilution may be partially prevented by the addition of supernatants of either ram or bull semen, although motility is not maintained at the same level as in a more concentrated specimen. Various other substances which also partially protect spermatozoa are egg albumin, plasma albumin, plasma gamma globulin, starch, and glycogen. 3. Washing ram spermatozoa six times greatly reduces motility. This is not restored by the addition of ram seminal plasma which, however, reverses the concurrent head agglutination. 4. Washing ram and bull spermatozoa four times results in considerable loss of motility and head agglutination both of which may be reversed by the addition of seminal plasma. 5. Potassium chloride at 0.005 M concentration partially restores the motility of four times washed ram spermatozoa at 24 degrees C. or 37 degrees C. but not that of similarly treated bull spermatozoa.  相似文献   

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The comparative ultrastructure of ejaculated boar, bull and ram spermatozoa is studied by scanning electron microscopy. After washing, the spermatozoa are fixed in glutaraldehyde or im picric acid-formaldehyde-glutaraldehyde mixture. Samples are prepared either by critical point drying (Freon) on Millipore filters or by air drying on glass cover slips. In all the species studied, three regions may be distinguished in the paddle-shaped head of the sperm: an anterior segment (surrounded by the marginal thickening) and an equatorial segment constituting together the acrosome, and the postacrosomal region. Most of the feature of the postacrosomal lamina described in transmission electron microscopy are visible through the plasma membrane, particularly after air drying. The surface morphology of the neck and of the different segments of the flagellum is also evident. Some species differences are encountered, e.g. rough surface of acrosome and absence of serrations in postacrosomal lamina of boar spermatozoa only. The techniques employed result in good general morphology and fine resolution of surface detail of the sperm samples; they also permit analysis of spermatozoa treated by freezing or submitted to acrosomal extraction.  相似文献   

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A simple method for rapid evaluation of bull and ram sperm concentration is described. In this technique, a sample from an undiluted specimen was placed in a special 10-mum counting chamber and examined either by an ordinary or a phase-contrast microscope. The pattern distribution of the observed spermatozoa was matched as closely as possible with one of five pictures of a standard scale. This scale was prepared from serial photomicrographs that ranged from 100 to 1500 million per ml. The number that appeared at the corresponding photograph immediately indicated the sperm concentration of the tested specimen. In this way values up to 1500 million per ml could be determined rapidly with no further procedures. More concentrated specimens needed slight dilution to make them suitable for direct evaluation. Accuracy and reliability were statistically evaluated; the mean deviation from the conventional method was less than 15.2% with confidence level of 95%.  相似文献   

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A method for displaying ram spermatozoan chromosomes using the interspecific zona-free hamster oocyte penetration was described to distinguish X- and Y-bearing spermatozoa. Semen samples from four rams were frozen and stored in liquid nitrogen. After thawing the samples, motile spermatozoa were collected by the swim-up method and treated with ionophore A23187 for the purpose of facilitating their capacitation. Slides were prepared by the gradual fixation-air dry method. The rates of oocyte penetration, first cleavage metaphase, and the number of ova that were karyotyped successfully were 67.9, 60.8 and 40.6%, respectively. The overall success rate (number of spermatozoa karyotyped/number of oocytes used for insemination) was 47.9%. A total of 1009 spermatozoa were analyzed, and the ratio of X- and Y-bearing spermatozoa was 508:501.  相似文献   

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Epididymal spermatozoa from bull, rabbit and ram were incubated in homologous epididymal plasma or seminal plasma in a buffered saline-based medium with or without serum albumin. The spermatozoa were either diluted directly into the medium or were washed first. No effect of washing was observed on the subsequent reaction of the cells to the different media. A considerable proportion of the populations of epididymal spermatozoa survived (i.e. continued to exhibit motility) for up to 22 h at 30 degrees C in the simple saline-based medium. Initially epididymal plasma had a slight stimulatory effect on sperm motility in ram and bull but it had no effect on sperm survival in any of the 3 species. Seminal plasma stimulated motility markedly in ram initially, but in all 3 species seminal plasma was detrimental to survival: in ram even a 15-min exposure to the fluid reduced survival. Serum albumin also stimulated motility; it delayed, but did not prevent, the detrimental effect of seminal plasma, although it had no effect itself on survival. The effects of epididymal plasma, seminal plasma and serum albumin on surface properties of epididymal spermatozoa, i.e. agglutination, sticking-to-glass and eosinophilia, were also noted. These varied between species and there was no correlation between these effects and the effects on motility and survival.  相似文献   

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