Laboratory methods of semen evaluation are used to select males for artificial insemination. The current review describes several techniques that have been recently used for sperm analysis. Conventional microscopic methods in combination with the objective computerassisted sperm motility and morphology analyzers and flow cytometry, allows to ob...tain more precise information about the membrane and functional status of spermatozoa. By using several methods to detect motility, viability, acrosomal and capacitation status besides DNA integrity sperm biology and some of the mechanism involved in sperm cry injury can be better understood. The number of possible targets related to sperm quality is increasing, and possible that some of them could enable sperm analysis for predicting freezability and fertility to be improved.
This study was carried out at the Hungarian National Artificial Insemination Centre in order to evaluate the seasonal effects on the quantitative and qualitative parameters of sperm production using sperm analyser equipment. The volume of ejaculate (VE), percentage of living sperm (PLS), spermatozoa concentration (SC), motility score (MC), perc...entage of motile spermatozoa (PMS), speed of movement of sperm cells (SMS) and the percentage of sperm cells moving straightforward (PSMS) were collected and observed in three seasons (summer, autumn, winter) in Holstein-Friesian breeding bulls (n = 15). The sperm collection was done for three successive weeks in every season on the same day (summer: n = 41, autumn: n=39, winter: n = 42, altogether: n = 122). The same sperm samples were measured by sperm analyser equipment (HTM version 7.0, Danvers) for PMS, SMS and PSMS. The seasonal and the number of sperm collection effects were confirmed on semen characteristics by multiple analysis of variance (two ways MANOVA, Type III) using the program package of STATISTICA 4.5. The average values of VE were similar in the three seasons (summer: from 4.42 to 6.28 cm3, autumn: from 4.08 to 6.86 cm3, winter: from 5.43 to 5.71 cm3). The average values of the MC were similar in each of the three seasons (summer: from 3.66-4.00 M; autumn: from 3.66-3.77 M; winter: from 3.86-4.07 M). The summary of all effects for season (P<0.001), repeated sperm collections in the same season (P<0.05) and interaction of two traits (P<0.01) were established on the measured characteristics. The special effects (P<0.05) of a given season were calculated, excepting the VE and MC, on all of the measured characteristics. The special effect (P<0.01) of the repeated sperm collections in the same season was verified in only one case (SMS). It is not surprised at the interaction was established on the VE (P<0.001), PMS (P<0.05), and SMS (P<10.0). The results of present study suggest that seasonal effect on sperm quality of breeding bulls cannot be eliminated even at standard feeding and keeping conditions. Considering our results, we can recommend that the average values of three successive weeks in every season be used, to take advantage of seasonal effect on the quantitative and qualitative parameters of sperm production.
Semen of 10 Tsigai,3 Prolific Merino and 7 Barbados Blackbelly rams was taken in January, out of the season. Split samples of the diluted semen samples were kept at 23, v.s. 8oC and their motilitywas evaluated daily for 3 days by subjective microscopic investigation. The ratio of motile spermatozoa was strongly decreased during the f...irst day, later the motility rate was sinking more slowly. It could be stated by multivariance analysis that the motility value of diluted semen of Prolific Merino rams was higher and showed a slower reduction as compared to the other two breeds. The decrease of the motility rates was slower at 8oC than at 23oC.
It could be stated that the diluted semen of Awassi rams taken in the breeding season preserved its fertilizing abilityat different temperatures for different periods of time. The motility of spermatozoa kept at 23 vs. 8oC was checked daily. The largest spread of data was observed 24 hours after taking the semen, then the motility ra...te of cells showed a linear decrease. Motility results of fresh and frozen-thawed samples were compared also after heat resistance test and significant differences were found between these groups. Significant individual differences were observedin the sperm motility after heat resistance test.