Freezing equine semen: the effect of combinations of semen extenders and glycerol on post-thaw motility   总被引：1，自引：1，他引：0  

J Scherzer  RA Fayrer-Hosken  M Aceves  DJ Hurley  LE Ray  L Jones  GL Heusner 《Australian veterinary journal》2009,87(7):275-279

Objective   We evaluated combinations of two commercial semen extenders and three concentrations of glycerol to determine the combination that yielded the highest post-thaw sperm motility.
Design   A randomised 2 × 3 block design was used.
Procedure   Semen was collected from four stallions (6 collections per stallion). The sample was diluted with either a dried skim-milk glucose extender (EZ Mixin Original Formula) or a chemically defined, milk-free diluent (INRA 96), and each was used in combination with 2%, 3% or 4% glycerol in standard commercial freezing medium. Sperm motility was assessed by microscopy in fresh and post-thaw semen.
Results   There was a significant difference between the two extenders in the motility of spermatozoa after cryopreservation (48.9% for INRA 96; 38.6% for EZ Mixin OF; P < 0.0001). Glycerol at 4% in freezing medium yielded the highest post-thaw motility, significantly better than 2% ( P < 0.05). Three of four stallions had significantly higher post-thaw motility using INRA 96 relative to EZ Mixin OF ( P < 0.01), and two of four stallions had significantly higher post-thaw motility using 4% glycerol ( P < 0.05). The combination of INRA 96 and 4% glycerol in freezing medium gave the highest average post-thaw motility of 51.5%.
Conclusion   In this study, INRA 96 combined with 4% glycerol yielded an average recovery of progressively motile sperm consistently above the 35% target.  相似文献   

Porcine β1,4-Galactosyltransferase-I Sequence and Expression     

EA Landers  HR Burkin  GT Bleck  L Howell-Skalla  DJ Miller 《Reproduction in domestic animals》2009,44(2):228-234

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Nitrogen status and transformations in coal mine spoil     

S. S. H. Shah  T. H. Flowers  I. D. Pulford 《Land Degradation \u0026amp; Development》1990,2(3):201-207

A detailed study was undertaken to measure mineral nitrogen status, mineralization rate of carbon and nitrogen, nitrification rate and fixation of added ammonium on 90 samples of coal mine spoils collected throughout Central Scotland. The inorganic nitrogen status of the spoils was very low (mean 3.4 mg N kg⁻¹). The rate of carbon dioxide evolution was high compared to the low rate of nitrogen mineralized, resulting in a mean mineralized C:N ratio of 178. Nitrification of added ammonium was measurable on only half of the samples studied. Spoil with pH < 4.8 showed no nitrification of added ammonium. However, on some sites above this pH no net nitrification was measured, which suggested the absence of nitrifying bacteria. A considerable amount of applied ammonium nitrogen was lost either as a result of ammonium fixation by clay minerals, or assimilation by the heterotrophic population due to the wide mineralizable C:N ratio.  相似文献