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At least 19 recordsLinked to original sources

PubMed1987

Effect of semen treatments and age of tom on fertility of unstored semen and semen held 18 hours.

Three experiments were conducted to determine the effects of semen dilution, semen extender, and age of tom on the fertility of unstored semen and semen stored for 18 h at 5 C. In Experiment 1, semen was diluted 2:1, 1:1, and 1:2 with Beltsville poultry semen extender (BPSE) #2. In Experiment 2, semen was diluted 1:1 with either Lake's extender, BPSE #2, or BPSE #1. In Experiment 3, the fertility of semen from males 30 to 45-wk-old (first reproductive cycle) was compared to semen from males 51 to 66-wk-old (second reproductive cycle). Identical experiments were conducted in the fall-winter (F-W) and in the spring-summer (S-S). All hens were inseminated with 250 million spermatozoa per dose three times prior to egg production, then weekly for 15 wk. Egg fertility was determined after 7 days of incubation. In all experiments there was a significant interaction between holding time and treatment (semen dilution ratio, semen extender, or age of tom). Fertility of stored semen diluted 1:2 in Experiment 1 was lower than stored semen diluted 2:1 or 1:1 regardless of time of year (season) the experiment was conducted. Fertility was affected by a significant interaction between season and semen dilution ratio. Fertility of semen from males in F-W was higher than semen from males in S-S (Experiment 1). Semen fertility was unaffected by season when comparisons were made between semen extenders (Experiment 2) or age of tom (Experiment 3). Fertility was affected by a significant interaction between season x holding time x age of tom.

Aging↗

PubMed1989

A survey of the concentration of 19-OH F1 alpha/F2 alpha prostaglandins in the semen of fertile, infertile and vasectomized men and their stability in both liquid semen and semen stains.

The levels of 19-hydroxy-prostaglandins F1 alpha/F2 alpha (PG F) in the semen of 19 vasectomized, 44 infertile and 8 fertile men were determined using a simple RIA technique. The mean concentrations observed in this survey were 45 micrograms/ml, 49.5 micrograms/ml and 59 micrograms/ml, respectively. No significant difference was recorded between the vasectomized and infertile groups; there were too few fertile samples available to undertake a meaningful statistical comparison. No reduction was observed in the levels of this PG in a liquid semen sample retained at room temperature over a 4 week period in the presence of a bacteriostat (sodium azide). However, a 30% reduction in the levels of 19-OH PG F occurred over the same time period when aliquots of the same semen sample were retained at either room temperature or at 4 degrees C without azide. Finally, no reduction was observed in the concentration of 19-OH PG F in a series of 10-microliters semen stains stored over a period of 6 weeks at room temperature.

Dinoprost↗

PubMed1998

Association between culturable human immunodeficiency virus type 1 (HIV-1) in semen and HIV-1 RNA levels in semen and blood: evidence for compartmentalization of HIV-1 between semen and blood.

Both qualitative and quantitative virologic measurements were compared between blood and genital compartments for 128 men infected with human immunodeficiency virus type 1 (HIV-1) to address several controversial issues concerning HIV-1 shedding in semen and to obtain further information about the distribution of virus between these two compartments. Evidence for viral compartmentalization was suggested by earlier studies that noted the poor correlation between blood and seminal virus load, phenotype, and genotype. Further support for this viral compartmentalization was based on the following observations between semen and blood: lack of association between culturability of virus in semen and viral RNA level in blood, discordant distribution of viral phenotypes, discordant viral RNA levels, a weak correlation between viral RNA level in semen and CD4 cell count in blood, differences in the biologic variability of viral RNA levels, and differences in the virus load response to antiretroviral therapy.

Adult↗

PubMed1989

Fertility in dogs in relation to semen quality and the time and site of insemination with fresh and frozen semen.

In this study 470 bitches were inseminated; 405 with fresh semen into the cranial vagina and 65 with frozen semen transcervically into the uterus. The pregnancy rate was 65.7% with fresh semen and 41.5% with frozen. When corrected for stage of oestrus at the time of insemination and for semen quality the pregnancy rate was 83.8% with fresh semen and 69.3% with frozen semen. The pregnancy rate improved with an increase in the number of inseminations. Inseminations with fresh semen before the time of ovulation (less than 17.3 nmol progesterone/l) were often successful. With frozen semen the peripheral plasma level of progesterone at the time of insemination was greater than 30 nmol/l in all but 1 of the bitches that became pregnant. This difference is assumed to be attributable to a longer survival time of several days for fresh semen than for frozen-thawed semen. Cytological scoring was a satisfactory method for determining the stage of oestrus when using fresh semen, but more precise methods are needed when using frozen semen. Semen quality was difficult to correlate with fertility. Pregnancies were obtained with fresh semen of inferior quality, although the litter size was smaller. With frozen semen no pregnancies resulted when the semen quality was poor. Litter size was estimated to be 21.5% smaller in bitches inseminated with fresh semen compared with naturally mated bitches. Litter size in bitches inseminated with frozen semen was 23.3% smaller than in bitches inseminated with fresh semen. Puppy deaths occurred in 35.5% of the litters in this study. The overall puppy death rate during the first 3 weeks of life was 11.9%. Although not statistically significant, there was a tendency for bitches treated with antibiotics at the time of mating or during early pregnancy to have a higher pregnancy rate and a larger litter size. There was also a tendency for breed differences in pregnancy rate, although not significant.

Animals↗

PubMed1997

Semen quality after thawing: correlation with fertility and fresh semen quality in dogs.

Fifty-four semen samples from five dogs were evaluated both, fresh and after thawing. Some of these semen samples were mixed with autologous prostatic fluid after thawing and used to inseminate each of nine bitches 4-7 times intravaginally. All bitches conceived and the mean number (+/- SD) of conceptuses, number of corpora lutea and ratio between conceptuses and corpora lutea (implantation rate) were 5.7 +/- 2.8, 9.4 +/- 1.1 and 0.63 +/- 0.34, respectively. The mean incidence of normal sperm morphology and progressively motile spermatozoa for all semen samples were 71.5 +/- 13.5% and 74.4 +/- 7.1%, respectively, in fresh semen and 52.0 +/- 18.5% and 53.4 +/- 12.6% in frozen-thawed semen. Extension rate was 1:3 for all semen samples and the mean sperm concentration after thawing was 12.08 +/- 6.66 x 10(7) ml-1. The only semen quality variables after thawing that were correlated with implantation rate were the number of spermatozoa inseminated on day-2 and number of progressively motile spermatozoa inseminated on day-2 (where day 0 is the day of onset of dioestrus as determined by cytology) (Spearman's rank correlation coefficient > 0.7, n = 9, P < 0.05). This study suggests that it is essential that frozen-thawed semen is inseminated on day-2 and that an insemination dose of 10-11 x 10(7) progressively motile frozen-thawed spermatozoa is adequate to achieve a mean implantation rate of 75% or higher. The incidence of either proximal or distal cytoplasmic droplets in fresh semen was negatively correlated with motility after thawing in three of five dogs (Spearman's rank correlation < -0.5, n = 6-17, P < 0.05). Neither the percentage spermatozoa with normal morphology in fresh semen nor the percentage progressively motile spermatozoa in fresh semen nor the concentration of spermatozoa after thawing were correlated with motility after thawing. Fresh semen quality, with the exception of the incidence of retained cytoplasmic droplets, has little value in predicting the progressive motility after thawing in frozen dog semen.

Animals↗

PubMed2003

Semen dilution prior to analysis influences the ability of the sperm quality analyzer to predict fertility whether inseminating with a constant number of sperm or a constant volume of semen.

Previous research has shown that the sperm quality index (SQI) is positively correlated with semen characteristics as well as fertility when broiler breeder semen is diluted 10-fold prior to analysis. However, research has not been conducted to establish if semen dilution rate affects the ability of the SQI to predict fertility when inseminating a constant number of sperm or a constant volume of semen. As a result, 3 experiments were undertaken. The objective of the first study was to determine if diluent, minimum essential media, or 0.85% saline affects the SQI. The second objective was to identify potential semen dilution rates for the SQI by obtaining the range in live sperm concentrations to which the SQI is most sensitive. The purpose of experiment 3 was to determine which semen dilution rate, 10-, 25-, 50-, 75-fold, or a constant concentration of 180 x 10(6) sperm/mL, yields an SQI that is most predictive of fertility. Once a week for 3 wk, 20 hens were individually inseminated with either 20 microL of 4-fold diluted semen or a constant 45 x 10(6) sperm from each of 29 broiler breeder males. To determine which semen dilution rate yielded an SQI that was most predictive of fertility, Pearson's correlation coefficients were obtained between the SQI at each dilution rate and fertility. There was no difference in the SQI due to diluent. Sperm quality index values declined logarithmically as live sperm concentration decreased. The SQI was most sensitive to live sperm concentrations from 11 to 232 x 10(6) sperm/mL. The SQI for semen diluted 10-fold was the best predictor of fertility when inseminating with a constant volume of 4-fold diluted semen (r = 0.71). When hens were inseminated with a constant 45 x 10(6) sperm/hen, the SQI for semen diluted 10- and 25-fold as well as to a constant concentration of 180 x 10(6) sperm/ mL was equally effective at predicting fertility (r = 0.59, 0.52, and 0.61, respectively). Apparently, the SQI is predictive of fertility when semen samples are diluted 10-fold prior to analysis regardless of insemination method used. Dilution beyond 10-fold appears to alter semen quality, rendering the SQI less accurate.

Animals↗

PubMed2003

Relationship between semen cultures, leukospermia, and semen analysis in men undergoing fertility evaluation.

OBJECTIVE: To determine the correlation between semen cultures, semen Gram stains, leukospermia, and semen analysis parameters in asymptomatic men undergoing fertility evaluation. DESIGN: Prospective clinical study. SETTINGS: Infertility clinic at a university teaching hospital. PATIENT(S): Two hundred ninety-nine asymptomatic men undergoing fertility evaluation. INTERVENTION(S): After an antibacterial skin preparation, all men gave semen specimens for culture, Gram stains, semen analysis, and assessment for leukospermia. MAIN OUTCOME MEASURE(S): A comparison of the presence or absence of bacteriospermia, the specific bacterial isolate, the quantity of bacteriospermia, the presence or absence of leukospermia, and semen analysis parameters. RESULT(S): The presence or absence of bacteriospermia or leukospermia did not correlate with each other. Leukospermia did not correlate with semen parameters. Staphylococcus species was the most common isolate (25.4% of all patients) and did not correlate with semen parameters or leukospermia. Streptococcus viridans (15.4% of all patients) and Enterococcus faecalis (7.4% of all patients) were the next most common isolates and were associated with statistically significantly poorer semen quality. CONCLUSION(S): Leukospermia is a poor marker for either bacteriospermia or impaired semen quality. Staphylococcus species are commonly isolated but appear to be innocuous. Streptococcus viridans and Enterococcus faecalis are associated with poorer semen quality and may warrant treatment.

Adult↗

PubMed1999

Secular and seasonal changes in semen quality among young Danish men: a statistical analysis of semen samples from 1927 donor candidates during 1977-1995.

The objective of this study was to investigate whether semen quality has changed during the years 1977-1995 in a group of unselected semen donor candidates, and to determine whether semen quality is subject to seasonal variation, by analysis of time- and season-related changes in semen quality using multiple regression and ANOVA. The study was based on analysis of the first semen sample delivered by 1927 semen donor candidates in Copenhagen during the period 1977-1995, with determination of semen volume, sperm concentration, total sperm count, percentage motile spermatozoa, and a semiquantitative sperm motility score. Multiple linear regression analysis with year, sexual abstinence and season as covariates showed a significant increase in mean sperm concentration from 53.0 x 10(6)/mL in 1977 to 72.7 x 10(6)/mL in 1995 (p < 0.0001) and in mean total sperm count from 166.0 x 10(6) to 227.6 x 10(6) (p < 0.0001). Mean semen volume and percentage motile spermatozoa did not change. Sperm motility deteriorated, as the spermatozoa in 74.2% of the samples were of excellent motility in 1977-1980 compared to only 41.9% in 1993-1995 (chi 2 = 130.0, p < 0.0001). Analysis of variance showed significant variation between seasons regarding sperm concentration (p < 0.0001) and total sperm count (p < 0.0001). Highest sperm counts were found in spring, with a mean concentration (95% C.I.) of 77.6 x 10(6)/mL (71.9-83.7), and lowest in summer, with a mean of 57.5 x 10(6)/mL (50.1-65.4). No other semen parameter varied with season. It is concluded that sperm counts increased, whereas sperm motility decreased, in a group of Danish semen donor candidates, from 1977 to 1995. Due to the retrospective design and the anonymity of the donors, we were unable to control for variation in donor age, and we cannot exclude the possibility that some donor candidates were selected by being accepted as donors by other semen donor services in Copenhagen. With these limitations in mind, we suggest our results should be interpreted cautiously and regarded as a contribution to the ongoing dispute on whether or not there is a continuous decrease in sperm quality. The seasonal variations found in sperm concentration and total sperm count were pronounced and were not attributable to seasonal differences in the length of sexual abstinence. Additionally, the same seasonal pattern was observed in five successive year-intervals. These findings strongly indicate that human testicular function is influenced by season, a phenomenon well known in many lower mammals.

Adult↗

PubMedDate not supplied

Effect of scrotal insulation on clusterin-positive cells in ram semen and their relationship to semen quality.

Scrotal contents of 2 rams were insulated for 96 hours and the fraction (as a percentage) of clusterin-positive cells (CPCs) and its relationship to semen quality was investigated. Semen collection was started 18 days before insulation and was terminated on day 78 and day 63 after insulation in animals 1 and 2, respectively. Sperm clusterin was localized by immunostaining with anti-bovine clusterin antibody (anti-bCAb) and fluorescein isothiocyanate-conjugated immunoglobulin G. Scrotal insulation led to deterioration of semen quality and increased the percentage of CPCs in both rams. Two types of sperm reactivity were observed: an extensive, intensive staining pattern (ESP); and a localized, less-intensive staining pattern (LSP). The percentage of ESP-CPCs began to increase from day 6 and reached 88.8% and 100% on day 15 after insulation in animals 1 and 2, respectively. The increase in CPCs coincided with the presence of a high percentage of teratoid forms (88.3%) in semen from animal 1, and detached heads (81.4%) in semen from animal 2. After normal semen production was restored on day 60 in animal 1, the percentages of ESP-CPCs and LSP-CPCs returned to preinsulation rates, whereas only the ESP-CPCs returned to normal in animal 2. A negative relationship was observed between ESP-CPCs and total sperm/ejaculate (r = -.62), motility (r = -.78), viability (r = -.68), and filtration rate (r = -.71) in semen from animal 1. Conversely, a positive relationship was seen between ESP-CPCs and total abnormal spermatozoa (r = .82). Similar results were obtained in semen from animal 2. CPCs were nearly completely absent in glass wool-Sephadex (GWS)-filtered semen, suggesting a role for clusterin in the process of trapping abnormal spermatozoa in the GWS filters. We conclude that aberrant spermatogenesis induced by scrotal insulation increases the percentage of CPCs in ram semen. We suggest that the percentage of CPCs in ram semen could be a useful marker in poor-quality ejaculates.

Animals↗

PubMed1999

HIV-1 in semen: determination of proviral and viral titres compared to blood, and quantification of semen leukocyte populations.

This study was carried out to determine the relationship between proviral DNA and viral RNA titres in semen compared with blood. In addition, the association between semen leukocyte counts with detection frequency and absolute levels of human immunodeficiency virus type 1 (HIV-1) nucleic acids was also assessed. Paired samples of blood and semen were collected from a cohort of individuals with different blood CD4 cell counts, and whose anti-HIV therapy had not changed in the preceding 3 months. The cell-associated proviral DNA titres and cell-free plasma viral RNA titres were determined using nested primer polymerase chain reaction and NASBAtrade mark, respectively. In addition, leukocyte counts were determined by immunocytochemical and cytochemical staining of a subset of semen samples. HIV-1 proviral DNA was detected in 100% and 47%, and viral RNA was detected in 76% and 63%, of blood and semen samples tested, respectively. HIV-1 proviral DNA and viral RNA titres in blood were higher than in corresponding semen samples, although the difference observed in viral RNA titres was not statistically significant. Proviral DNA and viral RNA titres were correlated between the two body fluids, and within the semen, although some individuals had disparate semen and blood titres or detection rates, indicating genital tract compartmentalisation. In addition, detection of HIV-1 proviral DNA, but not of HIV RNA, in semen was associated with elevated semen leukocyte counts, although this latter finding requires verification in future studies of larger numbers of patients.

CD4 Lymphocyte Count↗

PubMed1983

Semen quality in relation to semen preservation.

A goal of research in laboratory evaluation of semen has been ultimately to predict the fertility achievable with use of that semen. This would permit evaluation of the male and ejaculate. For artificial insemination, semen viability becomes a measure of man's interaction with that semen in an effort to preserve its functional life. Man's efficiency in developing successful methods of semen preservation are, therefore, contingent upon the relationship of tests of semen quality and fertility. Problems discussed are those associated with identification of the most appropriate tests of spermatozoan viability important to fertility. These problems reside predominantly in poor repeatability of many tests (objectivity versus subjectivity), the interaction of semen quality and quantity in the inseminate, the effect of latent cell injury encountered in some systems of preservation (example frozen semen), and identification of viability traits of spermatozoa important to their retention and transport in the female reproductive tract as well as their ability to fertilize the egg and sustain embryogenesis. A case is established for the use of more than one viability test or semen trait for evaluating systems of semen preservation.

Animals↗

PubMed1982

Influence of semen and donor factors on the success rate of artificial insemination with frozen semen.

Influence of some semen and donor factors on the success rate of artificial insemination by frozen donor semen (AID) was examined. The percentage of insemination cycles resulting in pregnancy was significantly higher for women who became pregnant within six cycles (33%) when compared with all the women in the AID programme (14%). Therefore the influence of semen and donor characteristics on the fertilizing capacity of frozen semen was studied in women who became pregnant within the first six cycles of insemination in order to minimize any influence of non-semen effects such as recipient and insemination factors. Donors less than 20 years of age appear to have a better chance of obtaining a pregnancy. Semen stored for less than six months in liquid nitrogen had a similar proportion of insemination cycles resulting in pregnancy compared with semen stored for longer than six months. Conventional semen values were not correlated with fertility, and none of these values could be used accurately to predict the fertilizing capacity of frozen semen.

Female↗

PubMed1998

Contrasting associations of blood and semen lead concentrations with semen quality among lead smelter workers.

While blood lead concentration has been inversely associated with indicators of reproductive health in occupationally exposed male workers, the utility of lead concentration in semen as an indicator of lead exposure to the male reproductive system has not been fully explored. Blood and semen lead concentrations from 81 lead smelter workers were examined in relation to semen quality and endocrine function parameters. Mean blood and semen lead concentrations were 22.8 micrograms/dl (range 5-58) and 1.9 micrograms/dl (range 0.1-17.6), respectively. Total sperm count and concentration decreased with increasing blood lead concentration; p for trend was 0.003 and 0.009, respectively. Semen lead concentration was inversely related to total sperm count (p = 0.05), ejaculate volume (p = 0.001), and serum testosterone (p = 0.004), but not to sperm concentration. The association between semen lead concentration and total sperm count was eliminated when volume was included in the model. Blood lead concentration was more consistently associated with indicators of sperm production than was semen lead. In contrast, semen lead concentration was negatively associated with circulating testosterone concentrations. Our findings indicate that measurement of semen lead may not be a valuable adjunct to conventional blood lead monitoring for investigations of male reproductive system toxicity.

Adult↗

PubMedDate not supplied

New semen quality scores developed by principal component analysis of semen characteristics.

The purpose of this study was to determine whether semen characteristics can be reduced to 2 semen quality (SQ) scores and whether these new scores can help the clinician in assessing the reproductive outcome. A cross-sectional sample of 250 patients seeking infertility treatment were analyzed for semen characteristics. In addition, 177 male-factor patients (prostatitis with infection, n = 40; varicocele, n = 77; varicocele with infections, n = 11; and vasectomy reversal, n = 43) were also assessed. Sperm motion kinetics were measured by computer-assisted semen analysis (CASA) (concentration, percent motility, curvilinear velocity [VCL], straight-line velocity [VSL], average path velocity [VAP], linearity [LIN], and amplitude of lateral head displacement [ALH]). Sperm morphology was assessed by both World Health Organization (WHO) guidelines and Tygerberg strict criteria. The principal component analysis model was used to construct an SQ score and a relative semen quality (RQ) score. A separate set of 25 normal donors was included as controls to determine normal ranges of the semen scores. Among the patient samples, SQ and RQ scores (median and 25% and 75% interquartile values) were 89.9, 25.1, and 130.4 and 106.1, 45.2, and 165.9, respectively. The SQ score for the varicocele and varicocele with infection groups was comparable (78.6 +/- 17.4 and 84.8 +/- 20.6) but significantly different from the control (100 +/- 10, P <.001 and.03). Vasectomy reversal patients had an SQ score of 78.2 plus or minus 16.8 that was significantly lower than controls (P <.001). The correlation among semen characteristics allows for the efficient combining of semen measures. The composite scores can summarize overall SQ and quantity. Both SQ and RQ scores provide meaningful information on the quality of semen specimens for the clinician.

Humans↗

PubMed2003

The effect of semen extender, seminal plasma and raw semen on uterine and ovarian blood flow in mares.

Transrectal color Doppler sonography was used to evaluate the effect of intrauterine infusion of skim milk semen extender, seminal plasma and raw semen on the endometrium and blood flow in the uterine and ovarian arteries in mares. Six Trotter mares (mean age: 12 years) were examined during estrus in three cycles. Each mare received an intrauterine infusion of 20 ml of skim milk semen extender, seminal plasma or raw semen during estrus in one of three cycles. Blood flow measurements in both uterine and ovarian arteries and the determination of intrauterine fluid via sonography were performed before each infusion and 1, 3, 6, 12, and 24 h after infusion. Forty-eight hours later, the intrauterine infusion and measurements were repeated using the same time intervals. Changes in blood flow were detected using transrectal color Doppler sonography and were evaluated using the mean time-averaged maximum velocity (TAMV) of the blood flow. Cytological and bacteriological examination of uterine swabs performed 48 h after the second infusion revealed less inflammation and bacterial growth in mares infused with skim milk semen extender than in those infused with seminal plasma or raw semen. There was an increase in intrauterine fluid as early as 1 h after infusion of any of the substances. The infusion of skim milk semen extender had no effect on uterine blood flow. Within 1 h after infusion of seminal plasma or raw semen, there was an increase in the TAMV values of both uterine arteries (P<0.05). In contrast, ovarian blood flow increased only in the artery ipsilateral to the preovulatory follicle and only after the infusion of raw semen (P<0.05). In conclusion, the changes in uterine perfusion observed after intrauterine infusion may be associated with endometrial inflammation and vasodilatory components in the seminal plasma, whereas the changes seen in ovarian blood flow are possibly attributable to the interaction between sperm and oviduct.

Animals↗

PubMed1999

Quality of stallion semen obtained by a new semen collection phantom (Equidame) versus a Missouri artificial vagina.

A study was performed to test a new semen collection device (Equidame phantom) that fractionates the ejaculate by comparing the quality of semen obtained by the Equidame phantom with that obtained by a Missouri artificial vagina. Semen from 4 Finnhorse stallions was collected 4 times per stallion by both methods. Half of the ejaculate was frozen and the other half extended and loaded into 2 Equitainer transport containers (24- and 48-h samples). Motility parameters were determined by a Hamilton-Thorn motility analyzer after cooled storage for 24 and 48 h and again after freezing/thawing. Raw and chilled semen samples were cultured and the number of bacterial colonies counted after incubations of 24 and 48 h. After a 24-h incubation the number of colony-forming units (CFU) in raw semen was significantly higher (P<0.01) when collected by the Missouri artificial vagina than by the Equidame phantom. After cooled storage, 75% of the semen samples contained no bacteria after an incubation of 24 h, and 69% yielded no growth after 48 h. The sperm-rich fractions (Cup 2) collected by the Equidame phantom had lower mean volumes (22.1 +/- 2.3 mL [+/- SEM] versus 101.6 +/- 9.3 mL) and significantly higher mean sperm concentrations (218.0 +/- 25.8 x 10(6) vs 86.2 +/- 8.1 x 10(6) cells/mL; P<0.05) than the total ejaculates collected by the Missouri device. The total and progressive motility of chilled and frozen-thawed semen did not differ significantly between collection methods. The Equidame phantom yielded semen that was of a lower bacteriological colony counts, but had sperm motility similar to that of semen collected with the traditional method by the Missouri artificial vagina.

Animals↗

PubMed1981

The effect of cooling rate before freezing and the temperature of the semen upon addition of DMSO on the fertilizing capacity of chicken semen stored at - 196 degrees C.

Semen was collected from Single Comb White Leghorn roosters, diluted 1:4 with Beltsville Poultry Semen Extender at 35 degrees C and cooled at various rates to 5 degrees C. DMSO was added to the semen between 10 and 120 min after ejaculation at temperatures between 15 and 5 degrees C, respectively. Following the addition of DMSO, the semen was allowed to equilibrate for 2 h in a 5 degrees C environment. The semen was then frozen at 1 degree C per min from 5 degrees C to - 20 degrees C, transferred into liquid nitrogen vapour for 4 to 10 min and then immersed in liquid nitrogen for 4 to 60 days. The thawed semen was inseminated on two consecutive days and fertility was calculated during 5 and 7 days commencing on the second day after the last insemination. In general, fertility was unaffected by the rate of cooling and the temperature at which the DMSO was added. In one trial, however, the fertilizing capacity was significantly greater if the DMSO was added within 45 min when the temperature of the semen was 15 degrees C. Approximately 42 to 71 p. 100 of eggs laid by hens during the 5 day period after the second insemination were fertile regardless of the method of cooling or the temperature of the semen when the DMSO was added. The motility of the ejaculates after thawing and before insemination varied between 15 and 55 p. 100 and this measure of physiological quality was a poor indicator of fertilizing capacity. Embryonic mortality was unaffected by the cooling and freezing procedure and hatchability of fertile eggs was not significantly different for the hens inseminated with either fresh or frozen semen.

Animals↗

PubMed2000

Human immunodeficiency virus type 1 shedding pattern in semen correlates with the compartmentalization of viral Quasi species between blood and semen.

High levels of human immunodeficiency virus (HIV) type 1 have been detected in semen at all stages of disease. However, it is not clear whether HIV-1 is shed in semen continuously or intermittently. In a prospective longitudinal study, viral RNA was measured weekly for 10 weeks in semen and blood of HIV-seropositive subjects. Results showed three different patterns of HIV-1 shedding in semen: none (28%), continuous (28%), and intermittent (44%). In contrast, there was no change in blood plasma virus load during the study period. Phylogenetic analysis of the envelope sequences of HIV-1 RNA in semen and blood revealed distinct virus populations in semen and blood of intermittent shedders but similar virus populations in the semen and blood of continuous shedder. These results indicate for the first time that HIV-1 is shed primarily in an intermittent manner and that shedding patterns of HIV-1 in semen are related to compartmentalization of HIV-1 between semen and blood.

Cell Compartmentation↗