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C G Gravance

Publications and source records attributed to C G Gravance.

At least 19 recordsLinked to original sources
PubMed2003

Activity of angiotensin-converting enzyme (ACE) in reproductive tissues of the stallion and effects of angiotensin II on sperm motility.

A testis-specific isoform of angiotensin-converting enzyme (ACE) has been identified in a number of mammalian species. The purpose of this study was to characterize the activity of ACE in equine spermatozoa, seminal plasma, and testis. Activity of ACE was determined in seminal plasma, ejaculated and epididymal spermatozoa from mature stallions as well as from pre- and postpubertal testis. The effect of addition of angiotensin II on equine sperm motility was also evaluated. The activity of ACE in detergent extracted sperm plasma membrane was approximately 13-fold higher than that detected in seminal plasma (93.7 mU/mg versus 7.0 mU/mg protein, respectively). Activity of ACE in equine testis was significantly higher in postpubertal than in prepubertal males (3.0 mU/mg versus 0.4 mU/mg protein, respectively), and ACE activity was reduced (P<0.001) in a dose-dependent fashion by the addition of captopril. The effect of angiotensin II on sperm motility was evaluated by computer-assisted semen analysis in sperm incubated with angiotensin II (0, 1, 10, 100 nM) at 38.5 degrees C. There was no significant effect of angiotensin II on the percent motile sperm; however, there was a significant main effect of angiotensin II (P<0.01) on the kinematic parameters beat cross frequency (BCF), average path velocity (VAP), and curvilinear velocity (VCL), respectively. In addition, there were significant stallionxconcentration interactions for amplitude lateral movement (ALH), BCF, linearity (LIN), straightness (STR), and VCL. This study demonstrates that ACE activity is present in sperm membrane from ejaculated and epididymal spermatozoa and in postpubertal testis. Further studies are required to determine the role of this testis-specific enzyme.

Angiotensin II↗
PubMed2001

Effect of antioxidants on preservation of motility,viability and acrosomal integrity of equine spermatozoa during storage at 5 degrees C.

Preservation of liquid semen at 5 degrees C is an important technique in the breeding management of horses. Oxidative damage to spermatozoa during storage is a potential cause of the decline in motility and fertility during hypothermic storage of liquid semen. The objective of this study was to evaluate the use of water-soluble and lipid-soluble antioxidants to improve the maintenance of motility of equine spermatozoa at 5 degrees C during storage for 72 to 96 h. In Experiment 1, the effect of addition of catalase on the maintenance of motility, viability and acrosomal integrity was determined. Semen was collected, and these treatments were applied: catalase (0, 100 or 200 U/mL) in nonfat, dried skim milk extender (NFDSM; with or without seminal plasma) or 10% seminal plasma + NFDSM. Motility was determined by computerized semen analysis (CASA) at 0, 24, 48 and 72 h. Viability and acrosomal integrity were determined at 72 h of storage. There was no significant treatment effect on the maintenance of sperm motility during 72 h storage. In Experiment 2, the effect of adding lipid-soluble antioxidants on maintenance of motility was evaluated. Semen was diluted to a final concentration of 25 x 10(6) sperm/mL in NFDSM containing butylated hydroxytoluene (BHT; 2.0, 1.0, or 0.5 mM), Vitamin E (4.0, 2.0, 1.0 mM), or Tempo (2.0, 1.0, or 0.5 mM). Although the addition of BHT significantly reduced (P < 0.05) progressive motility during storage compared to the control, there were no positive treatment effects of either Vitamin E or Tempo on maintenance of motility. In Experiment 3, the effect of adding water-soluble antioxidants on maintenance of motility was evaluated. Semen was diluted in NFDSM containing these treatments: Trolox (2.0 mM), Tempo (1.0 mM), Vitamin C (0.45 mg/mL), BSA (3% w/v), combinations of these antioxidants, or control. Adding these water-soluble antioxidants did not significantly improve the maintenance of motility during cooled storage at 5 degrees C. In conclusion, adding the enzyme scavenger, catalase, or a variety of lipid- and water-soluble antioxidants did not significantly improve the maintenance of motility during liquid semen storage at 5 degrees C.

Acrosome↗
PubMed2001

Seminal plasma addition attenuates the dilution effect in bovine sperm.

Dilution of semen to low cell numbers/dose can result in a bull-dependent reduction in the post-thaw viability of cryopreserved bovine spermatozoa. It is possible that essential seminal plasma components are lacking at the greater dilution rates, thereby contributing to the deleterious effects of semen dilution. Ejaculates of 6 Holstein bulls were diluted to 120 x 10(6) sperm/mL in an egg yolk citrate extender (EYC). Split samples were further diluted to 80, 40, 20 and 4 x 10(6) sperm/mL in EYC extender with (+SP) and without (-SP) the addition of frozen/thawed seminal plasma previously obtained from a vasectomized bull. Serial dilutions for the +SP treatments were calculated and performed such that each dilution contained a volume of seminal plasma equal to the original 120 x 10(6) sperm/mL dilution. Samples were then loaded into 0.5-mL French straws yielding final sperm concentrations of 30, 20, 10, 5 and 1 x 10(6)/dose. Straws from each dilution were analyzed using 2 stain combinations: the sperm viability stain, SYBR-14 and propidium iodide (PI); or the mitochondrial-specific, membrane potential-dependent stain JC-1 along with PI. Split-plot analysis of variance indicated that within bulls, there were greater proportions of viable spermatozoa in aliquots containing added seminal plasma than in aliquots without added seminal plasma (P < 0.05). Contrast analyses showed that sperm viability significantly decreased as sperm concentration decreased in the -SP samples. Although the dilution effect was also observed in the +SP samples, the magnitude of the effect was less than in the -SP samples. At most sperm concentrations, the proportions of spermatozoa that stained with JC-1 were correlated (r > 0.84; P < 0.05) with the percentages of SYBR- 14 stained spermatozoa. Furthermore, the proportions of JC-1-stained spermatozoa were greater in the +SP aliquots than in the -SP samples at a concentration of 10 x 10(6) sperm/0.5 mL. These results suggest that the addition of seminal plasma can be beneficial to sperm viability when semen is diluted to low cell numbers/dose.

Animals↗
PubMed2000

Assessment of equine sperm mitochondrial function using JC-1.

The fluorescent carbocyanine dye, JC-1, labels mitochondria with high membrane potential orange and mitochondria with low membrane potential green. Evaluation of mitochondrial membrane potential with JC-1 has been used in a variety of cell types, including bull spermatozoa; however, JC-1 staining has not yet been reported for equine spermatozoa. The aim of this study was to apply JC-1 staining and assessment by flow cytometry or a fluorescence microplate reader for evaluation of mitochondrial function of equine spermatozoa. Six ejaculates from four stallions were collected and centrifuged through a Percoll gradient (PERC). Spermatozoa were resuspended to 25 x 10(6) cells/mL, samples were split, and one sample was repeatedly flash frozen (FF) in LN2 and thawed. The following gradients of PERC:FF were prepared: 100:0 (100), 75:25(75), 50:50 (50), 25:75 (25) and 0:100 (0). Samples were stained with 2.0 microM JC-1 and assessed for staining by flow cytometry and by a fluorescence microplate reader. A total of 10,000 gated events was analyzed per sample with flow cytometry. The mean percentage of cells staining orange for the 100, 75, 50, 25 and 0 treatments was 92.5, 72.8, 53.4, 27.3 and 7.3, respectively. The expected percentage of spermatozoa forming JC-1 aggregates was correlated with the actual percentage of orange labeled sperm cells determined by flow cytometry (r2=0.98). Conversely, JC-1 monomer formation was negatively correlated with expected mitochondrial membrane potential (r2=-0.98). The blank corrected orange fluorescence, assessed by microplate assay, was significantly (P<0.0001) correlated with the expected (r2=0.49) and with the flow cytometric (r2=0.50) determination of percentage of spermatozoa with mitochondria of high membrane potential. Total orange and orange:green fluorescence was also correlated with mitochondrial function. These results indicate that JC-1 staining can accurately detect changes in mitochondrial membrane potential of equine spermatozoa. The relative fluorescence of JC-1 labeling patterns of equine spermatozoa can be accurately and objectively determined by flow cytometry and by a fluorescence microplate reader assay.

Animals↗
PubMed2000

Catalase activity in equine semen.

OBJECTIVE: To characterize the activity of catalase in equine semen. ANIMALS: 15 stallions of known and unknown reproductive history. PROCEDURE: Seminal plasma was collected from raw equine semen by centrifugation, and samples of seminal plasma were frozen prior to assay for catalase activity. Tissue samples (n = 3 stallions) from the bulbourethral gland, prostate gland, vesicular gland, and testis were homogenized, and cauda epididymal fluid was collected for determination of catalase activity. Catalase activity was determined as an enzyme kinetic assay by the disappearance of H2O2 as measured by ultraviolet spectrophotometry. RESULTS: Catalase activity in equine seminal plasma was 989.3 +/- 1678 U/ml (mean +/- SEM), and the specific activity of catalase in equine seminal plasma was 98.7 +/- 29.2 U/mg of protein. Specific activity of catalase in tissue homogenates was significantly higher in the prostate gland (954 +/- 270 U/mg of protein) than in the ampulla (59 +/- 5 U/mg of protein), bulbourethral gland (54 +/- 11 U/mg of protein), vesicular gland (39 +/- 3 U/mg of protein), cauda epididymal fluid (11 +/- 3 U/mg protein), or testis (54 +/- 6 U/mg of protein). CONCLUSIONS AND CLINICAL RELEVANCE: Equine seminal plasma contains a high activity of catalase that is derived primarily from prostatic secretions. Procedures such as semen cryopreservation that remove most seminal plasma from semen may reduce the ability to scavenge H2O2 and thereby increase the susceptibility of spermatozoa to oxidative stress.

Amitrole↗
PubMed1999

Replicate and technician variation associated with computer aided bull sperm head morphometry analysis (ASMA).

Associations of abnormal spermatozoa with bull fertility have yielded varying results. Manual methods of analysis are subjective and highly variable within and between technicians, which may account for these differences. Computer-aided sperm head morphometry appears to be a precise method of assessing sperm head dimensions; however, the effects of replication and technician on sperm head morphometry have not been assessed. The objective of this study was to determine the inter- and intra-analysis and technician variation associated with computer-aided bull sperm head morphometry analysis. Semen from 10 bulls was diluted to 200 x 10(6) sperm/mL, and slide smears were prepared and stained using haematoxylin and rose bengal. Each of two technicians analysed 250 images from each slide, 3 times, using computer-aided sperm head morphometry analysis. The morphometric dimensions of area, perimeter, length, width and width/length for individual sperm heads of each analysis were assessed by GLM-ANOVA for effects of bulls, replications and technicians. The coefficient of variation was recorded for each analysis and across replications. The mean coefficients of variation within and between analyses were compared between technicians by GLM-ANOVA. No differences (p > 0.1) between technicians were found between or among bulls for area (29.63 vs. 29.26 micron 2), perimeter (23.73 vs. 23.86 microns), length (8.73 vs. 8.71 microns), width (4.47 vs. 4.46 microns), or width/length (0.51 vs. 0.51). No differences (p > 0.1) between replicates for sperm head dimension were detected within or among bulls for either technician. No intra- or inter-analysis differences (p > 0.1) between technicians on CVs were observed. The mean intra-analysis CVs for all bulls for both technicians were area = 6.9%, perimeter = 4.9%, length = 4.5%, width = 5.6% and width/length = 6.5%. The mean interanalysis CVs for both technicians were area = 3.0%, perimeter = 2.4%, length = 2.0%, width = 2.0%, and width/length = 1.7%. The results indicate that ASMA is a repeatable and objective method of assessing bull sperm head morphometry within and between technicians. No differences between replications were detected, and hence replicate analyses are not necessary to acquire accurate morphometric data.

Animals↗
PubMed1999

IGF-I treatment increases motility and improves morphology of immature spermatozoa in the GH-deficient dwarf (dw/dw) rat.

It has recently been shown that short-term growth hormone (GH) treatment can increase the motility of spermatozoa in the GH-deficient dw/dw rat. To examine whether the effects of GH on motility of immature spermatozoa are mediated by an increase in plasma concentrations of IGF-I, we treated GH-deficient dw/dw rats with 2 microg/g/day of IGF-I using osmotic minipumps. Body weight (saline 227+/-5 g, IGF-I 253+/-4 g) and IGF-I concentrations in blood plasma (saline 472+/-19.9 ng/ml, IGF-I 986+/-43.6 ng/ml) and seminal vesicle fluid (saline 30.9+/-1.7 ng/ml, IGF-I 47.9+/-2.9 ng/ml) were significantly increased with IGF-I treatment (P<0.001), similar to the observed responses to GH therapy in our earlier study. While epididymal fluid IGF-I concentrations were not changed, IGF-I treatment significantly increased the number of immature motile spermatozoa (saline 14.4+/-3.5%, IGF-I 28.3+/-4.1%, P<0.05) and the number of spermatozoa with normal morphology (control 65.7+/-3.3%, IGF-I 75+/-1.9%, P<0.05). These data suggest that increasing the circulating concentrations of IGF-I in the GH-deficient rat can improve the motility and morphology of immature spermatozoa and thus mimic, at least in part, the effects of GH.

Animals↗
PubMed1998

Computer-assisted sperm head morphometry analysis (ASMA) of cryopreserved ram spermatozoa.

Normal sperm morphology has been shown to be indicative of male fertility; however, subjective methods of assessing morphology are highly variable. Computer-assisted sperm morphometry analysis (ASMA) has been developed for the objective analysis of sperm head dimensions. Developing applicable protocols for sperm head morphometry analysis increases the efficiency of these systems. The objective of the current study was to develop accurate methods for employing ASMA of ram sperm heads. Staining methods, optimal sperm sample numbers microscopic magnification and sampling variation within and between technicians were assessed. Frozen semen from 10 fertile rams was thawed and prepared on slides for morphometric analysis. Staining spermatozoa with hematoxylin and rose bengal stains yielded the best results. Ram sperm head morphometry was accurately evaluated on at least 100 spermatozoa at x 40 objective magnification. Using these techniques, a sample could be analyzed in approximately 3 min. No significant differences in sperm head measurements were detected between 2 technicians. The system properly recognized and digitized ram spermatozoa 95% of the time. The morphometric measurements of sperm heads for all rams were as follows: length = 8.08 microns, width = 4.80 microns, width:length ratio = 0.59, area = 29.13 micron 2 and perimeter = 23.93 microns. The mean within analysis coefficients of variation for all individual analyses and parameters ranged from 4.8% for length to 6.0% for area. The variation between replicate analysis was 2.4% or less for both technicians. When applying proper sample preparation and analysis procedures no differences in measurements or variation were observed between the 2 system operators.

Animals↗
PubMed1998

Percentage of normal sperm heads is significantly increased by Percoll separation of semen.

The purpose of this study was to assess objectively the effects of Percoll separation on human sperm head morphometry. Semen samples were washed and smears were prepared on slides. An aliquot of each sample was centrifuged on a Percoll gradient and spermatozoa were prepared on slides. Dimensions of sperm heads from each sample were assessed by computer-aided sperm head morphometry analysis and manual sperm morphology was assessed for each sample. The percentage of normal sperm heads and morphometric dimensions from washed and post-Percoll separated samples were compared across all men by a paired t-test. Correlations between normal sperm head morphometry and manual sperm morphology were assessed in washed and Percoll-separated samples. The percentage of normal sperm head morphometry was significantly (p < 0.001) higher in Percoll-separated samples than in washed samples (23.6 vs. 12.6%). No differences (p > 0.1) in mean sperm head measurements were detected between washed samples and Percoll-separated samples. Coefficients of variation for mean sperm head measurements were significantly lower in Percoll-separated samples. No correlation (p > 0.1) in percentage normal was found between computer-assisted sperm head morphometry and manual morphology for washed and post-Percoll samples. These results indicate that percentage normal sperm head morphometry is increased by Percoll separation. While sperm head dimensions were unchanged, sample variability was decreased.

Cell Separation↗
PubMed1997

Morphometric differences in sperm head dimensions of fertile and subfertile stallions.

Gross morphological evaluation of stallion spermatozoa is of clinical value in assessing male fertility in the horse. While of value, methods of subjective sperm classification yield highly variable results. Recent development of computer-assisted sperm morphometry analysis (ASMA) technology has allowed for the objective analysis of sperm head morphometry. In the current study, ASMA was employed to determine morphometric differences in sperm head dimensions between fertile and subfertile stallions. At least 200 spermatozoa from each of 10 fertile and 10 subfertile stallions were analyzed by a commercial ASMA instrument. The mean measurements for length, width, area, perimeter, and width/length for each stallion were recorded and group means compared by a two-sample t-test. The mean measurements for length, area and perimeter were significantly larger in the subfertile than the fertile group (5.77 microm vs 5.33 microm, 12.66 microm vs 11.37 microm and 14.59 microm vs 13.64 microm, respectively). The width of sperm heads from stallions in the subfertile group also tended to be larger than those of fertile stallions. The data suggest that differences in the dimensions of sperm heads may exist between fertile and subfertile stallions.

Journal Article↗
PubMed1997

Sperm head morphometry analysis of ejaculate and dismount stallion semen samples.

The evaluation of seminal characteristics is important in the clinical detection of stallion subfertility. Conventional semen evaluation includes subjective determination of sperm concentration, motility, and gross morphology. Due to the subjectivity and variability of the manual morphology assessment, computer automated sperm morphology analyses has been developed. Computer automated sperm morphology analysis was applied in the current study to determine if the morphometric measurements of sperm heads from collected and dismount samples of the same ejaculate were similar. If the post-ejaculate dismount sample is representative of the entire ejaculate, this sample may be utilised in determining the fertility of the ejaculate. Ejaculate samples were collected from ten stallions using an artificial vagina. Post-ejaculate dismount samples of the same ejaculate were taken from the head of the penis. A thin smear of the collected and dismount samples were prepared onto microscope slides and spermatozoa were stained for 40 min in haematoxylin. At least 200 properly digitised sperm heads from each slide were analysed using computer automated sperm morphometry analysis. The mean values for length, width, width/length, area, and perimeter were recorded from each analysis of collected and dismount samples and compared by paired t-test. The coefficients of variation of each analysis was also recorded and compared between collected and dismount samples by paired t-test. No significant differences (P > 0.10) in any measurements were found between collected and dismount samples. The mean values for all stallions for collected and dismount samples were length = 5.96 microM and 6.06 microM, width = 2.95 microM and 2.98 microM, width/length = 0.49 and 0.49, area = 13.31 microM2 and 13.65 microM2 and perimeter = 15.54 microM and 15.74 microM respectively. No significant differences were detected in the coefficients of variation of sperm head measurements from collected and dismount samples. These results indicate sperm head measurements from dismount semen are representative of those of the ejaculate. Hence, sperm head measurements of dismount samples may be viably applied to studies of fertility or in case of clinical fertility assessment. This finding will further assist in the development of normal sperm head morphometry criteria in the stallion. Clinically, a slide can be prepared in the field after natural services matings and analysed accurately and objectively by ASMA.

Animals↗
PubMed1997

Impaired sperm characteristics in postpubertal growth-hormone-deficient dwarf (dw/dw) rats.

The objective of the current study was to determine if sperm function is compromised in rats deficient in growth hormone (dw/dw) since a deficiency in this hormone has been implicated as a cause of lowered fertility and spermatogenic cessation in some biological models. Spermatozoa were recovered from the cauda epididymides of adult dwarf and Wistar control male rats. Spermatozoa were diluted in Medium 199 and analysed for motility. Aliquots were then fixed in phosphate buffered formalin, sperm concentration determined and morphology assessed. The mean measurements for percent motile and normal morphology were compared by Student's t-test. Sperm concentrations were compared by Mann-Whitney two sample test. The mean percentage of motile spermatozoa was significantly greater in the Wistar control group than in the dwarf group (75 +/- 1.44 vs 28 +/- 3.71%, P < 0.001). The percentage of normal sperm morphology was also greater in the Wistar control group (88 +/- 1.00 vs 75 +/- 6.9%, P < 0.001). The concentration of spermatozoa in the cauda epididymis was also significantly higher in the Wistar group. These results indicate that sperm function parameters are diminished in growth-hormone-deficient dw/dw rats. The effects of growth hormone deficiency in rats appears to be associated with compromised spermatogenesis as well as impaired sperm motility. The GH-deficient rat appears to be a suitable model for the study of the effects of GH on sperm characteristics.

Animals↗
PubMed1997

The effects of cryopreservation on the morphometric dimensions of caprine sperm heads.

Cryopreserved semen has been utilised in the artificial insemination of livestock species for over 40 years, even though the detrimental effects of cryopreservation on sperm function and fertility are well documented. In the present study, computer-automated sperm-head morphometry was used to determine if goat sperm-head morphometry was affected by freezing and thawing. A microscope slide was prepared from single semen samples, collected by artificial vagina, from 10 sexually active Saanen bucks. The remainder of each sample was frozen in a tris-citrate-yolk extender. After thawing, semen smears were prepared on microscope slides. All slides were stained in haematoxylin and mean sperm-head measurements of length, width, width/length, area and perimeter were determined for each slide by computer aided sperm morphometry analysis. The effects of sperm freezing on sperm-head dimensions within and among all bucks were determined. No significant (P > 0.10) freezing effect was found between fresh semen and postthaw samples for length (7.00 microns vs 7.13 microns), width (3.77 microns vs 3.87 microns), width/length (0.54 micron vs 0.54 micron), area (19.67 microns2 vs 20.57 microns2) and perimeter (18.62 microns vs 18.83 microns) when analysed across all bucks. Significant differences (P < 0.05) were however found within three bucks for area, perimeter, length and width, with the percentage increase in measurements being significantly greater than in the remaining bucks. The variability of the morphometric dimensions were not affected by freezing. The results indicate that semen freezing did not affect the overall dimensions of sperm heads across the entire population of bucks sampled. However, since sperm-head dimensions from three bucks were affected, changes in sperm-head morphometry may be indicative of spermatozoa of the semen from individuals to successfully freeze. Because the overall mean sperm-head dimensions acquired from frozen/thawed semen were not different from those of fresh semen, previously reported measurements of goat sperm heads are probably reflective of fresh semen. More importantly, retrospective studies of sperm-head morphometry and fertility may now be performed utilising extensive breeding records from frozen semen.

Animals↗
PubMed1996

Progesterone does not inhibit aggression induced by testosterone metabolites in castrated male mice.

Sufficient data exist indicating that testosterone (T) or metabolites of T, i.e., dihydrotestosterone (DHT) and estrogen (E), induce aggressive behavior. The effects of T have also been shown to be suppressed by concurrent administration of progesterone (P). It is unknown if the effects of P are exerted on T directly or upon the T metabolites. The objective of this experiment was to evaluate the inhibitory effects of P on aggression induced by T and T metabolites. Seven male mice were randomly allocated to one of the following treatment groups: castration (C), C + T, C + 5 alpha-dihydrotestosterone (DHT), C + estrogen (E), C + DHT + E (DE), T + P, and DE + P. The males were then placed with androgenized females in three 10-min trials to determine the effects of each treatment on hormone induced aggression. The degree of aggressive behavior displayed was measured by number of trials where attacks occurred (N), mean latency to attack (L), frequency of attacks (AF), duration of attacks (D), and a composite index score (INDEX). All androgen treated groups showed significantly higher degrees of aggression compared to C and T + P animals. P inhibited aggression in T-treated males but did not inhibit aggression in the DE treated group. The data suggest that P inhibits the aggressive effects of T by acting on receptors of the metabolite-producing enzymes or by direct competitive binding for 5 alpha-reductase.

Aggression↗
PubMed1996

Growth hormone (GH) therapy markedly increases the motility of spermatozoa and the concentration of insulin-like growth factor-I in seminal vesicle fluid in the male GH-deficient dwarf rat.

There is increasing evidence for an important role of the somatotropic axis in male reproductive function. We investigated the effect of recombinant bovine GH (rbGH) treatment for 21 days on semen characteristics in post-pubertal GH-deficient dwarf (dw/dw) rats. Male dw/dw rats at an age of 75-80 days were divided into two groups (n = 10 per group) and injected twice per day with either rbGH (2 micrograms/g/day) or saline. While the concentration (96.4 +/- 51.3 x 10(6) per ml) and morphology of spermatozoa (spermatozoa with normal morphology 73.5 +/- 6.3%) in the dw/dw rat were within the normal range, the motility of spermatozoa was very low (27.5 +/- 11.7%), establishing a state of sub-fertility. The rbGH treatment markedly increased (p < 0.01) motility of spermatozoa (44.5 +/- 10.7%) but did not change the concentration (144 +/- 80.3 x 10(6) per ml) and morphology (spermatozoa with normal morphology 79.5 +/- 6.0%). The rbGH treatment also significantly increased the concentration of insulin-like growth factor-I (IGF-I) in blood plasma (control 389.1 +/- 65 ng/ml, rbGH 813.9 ng/ml, p < 0.001) and in seminal vesicle fluid (control 11.3 +/- 3.0 ng/ml, rbGH 16.1 +/- 5.4 ng/ml, p < 0.05). We conclude that rbGH therapy markedly increases motility of spermatozoa in sub-fertile male GH-deficient dw/dw rats. Thus, GH therapy may offer considerable potential for the treatment of impaired male reproductive performance.

Animals↗
PubMed1996

Quantification of normal head morphometry of stallion spermatozoa.

The heads of stallion spermatozoa were analysed by computer automated sperm head morphometry and the morphometric values of the major subpopulations of sperm heads were assessed. The criteria for normal dimensions of stallion sperm heads are proposed based on the analysis of these measurements. Semen samples were collected from 10 fertile and 10 subfertile stallions, processed by a standard method, smeared onto microscope slides and stained using haematoxylin. At least 200 properly digitized sperm heads were analysed from each stallion. The measurements for length, width, area, perimeter and width/length were recorded for each stallion. All sperm head measurements were placed in a statistical database and multivariate cluster analysis performed. Mean measurements for all parameters of the major clusters of fertile and subfertile stallions were compared by analysis of variance. The ranges of the values of the major clusters of fertile stallions were applied to all stallions to determine the percentage of normal sperm heads for each stallion. The mean values for length, width, area and perimeter in the major cluster of sperm head dimensions of fertile stallions were significantly different from those of the subfertile stallions (P < 0.001). The range of values of the major cluster of fertile stallions was length = 4.9-5.7 microns, width = 2.5-3.0 microns, width/length = 0.45-0.59, area = 10.3-12.1 microns2, and perimeter = 12.9-14.2 microns. On the basis of these values, a significantly (P < 0.001) higher percentage of normal sperm heads were found in the fertile group than in the subfertile group of stallions (52% versus 19%).

Analysis of Variance↗
PubMed1995

Computer automated sperm head morphometry analysis (ASMA) of goat spermatozoa.

The development of computer automated sperm morphometry analysis (ASMA) allows for the objective analysis of sperm head dimensions. A number of studies have been performed to optimize the efficiency of these systems when analyzing spermatozoa from a variety of species. In this study, frozen semen from 10 fertile goat bucks was thawed and prepared on slides for morphometric analysis to evaluate technical variation and to standardize ASMA procedures for goat spermatozoa. Methods of staining, the number of spermatozoa necessary to sample and optimal microscopic magnification were assessed. Staining for 20 min in hematoxylin (HEM) was found to be optimal. The most efficient method of analyzing goat sperm morphometry was to evaluate 100 sperm cells at x20 objective magnification. Using these techniques, a sample could be analyzed in approximately 2 min. The system properly recognized and digitized spermatozoa 96% of the time with a target recognition error rate of less than 1%. The morphometric measurements of sperm heads for all 10 bucks were the following: length = 7.69microm, width = 3.80microm, width/length ratio = 0.5, area = 22.82microm and perimeter = 20.15microm. The mean coefficients of variation (CV) for all bucks ranged from 3.4% for length to 5.8% for area. Standardized sample preparation techniques and analysis were found to improve the efficiency of ASMA.

Journal Article↗