Showing papers on "Semen published in 1970"

A Uterine Fluid-Mediated Sperm-Inhibitory System

Abstract: The report suggests that uterine fluid under certain conditions exerts a sperm inhibitory effect. The addition of rat uterine fluid iodide and hydrogen peroxide to washed spermatozoa suspended in a calcium ion-free Krebs-Ringer phosphate fructose medium pH 6.5 resulted in an inhibition of motility which was complete in 10 min. When the spermatozoa were incubated in medium alone they remained fully motile for 2 hr. Deletion of hydrogen peroxide from the system abolished the sperm-inhibitory effect. Some inhibition of motility was evident on prolonged incubation when either uterine fluid or iodide was deleted. Thiocyanate could substitute for iodide and glucose and glucose oxidase could substitute for hydrogen peroxide giving 94% and 95% inhibition respectively. The uterine fluid could be replaced by a preparation of LPO (lactoperoxidase) or less effectively by MPO (myeoperoxidase). This suggests that its sperm inhibitory effect is due to its perioxidase content. The uterine fluid-iodide-hydrogen peroxide system suspended spermatozoa resulted in a decrease in pyruvate oxidation. Unwashed spermatozoa were unaffected by the system suggesting inhibitors in seminal plasma. This was born out by tests which showed the system was inhibited by catalase and by such low-molecular-weight compounds as azide reduced glutathione cysterine ergothioneine and ascorbic acid. Heat-stable low-molecular-weight inhibitors are found in seminal plasma and to a lesser degree in uterine fluid.

Fertility of ram spermatozoa frozen by the pellet method ii. the effects of method of insemination on fertilization and embryonic mortality

Abstract: Summary. A factorial experiment was conducted to examine the effects in Merino ewes of method of insemination and semen type on embryonic loss (fertilization rate versus lambing rate). The results showed that: (i) frozen semen (pellet method) was of lower fertility than fresh semen (49% versus 70% respectively). (ii) there was little embryonic mortality following either the cervical or cervical traction methods of insemination (13% and 6% respectively), but substantial loss occurred following uterine insemination (47%). Results for both fresh and frozen semen were similar in this respect. Normal cervical insemination (two inseminations at a 12-hr interval within one oestrus) with frozen semen of high concentration (1-6 IO9 motile spermatozoa/ml, 0-1 ml dose) resulted in ewe fertilization and lambing rates of 58% and 50%, respectively.

Failure of Conception in Rabbits Inseminated with Nonagglutinating, Univalent Antibody-Treated Semen

Abstract: Guinea pig anti-rabbit sperm and control y globulin were digested to nonagglutinating, univalent (3.5S) fragments with papain. Samples of rabbit semen (0.3 ml) were incubated (30 mm) with 1-mI samples of the univalent or undigested parent y globulin preparations and then used to artificially inseminate female rabbits. After 6 days the females were examined for blastocysts, ova, and corpora lutea. In five such experiments, all females which received the digested, and four of the five which received the undigested control y globulin, yielded blastocysts. In terms of corpora lutea, the percentages of blastocysts were 111 and 69%, respectively. In the antibody-treated series blastocysts were found in only one female with digested and none in those treated with undigested antibodies (16 and 0%, respectively). Since sperm are not agglutinated by univalent antibody and their motility was not visibly affected, these two factors do not explain the conception failures in the univalent antibody-treated series. Therefore, the experimental procedure was repeated but with examination of flushings of the female tracts for sperm at approximately 12 hr. Flushings from females inseminated with digested control y globulin-treated semen contained approximately 50 times more spermatozoa than those from females inseminated with digested antibody-treated semen. it is suggested that univalent antibody blocks some sperm (surface ?) antigen that has an important role in penetration of cervical mucus.

Artificial cryptorchidism and fertility in the rabbit.

Abstract: The correlation between the quantitative changes in the semen resulting from artificial cryptorchidism and the ability of the spermatozoa to reach and fertilize ova and the ability of the fertilized ova to under normal embryogenesis was investigated in rabbits in which the testes were surgically anchored to the abdominal wall. By 6 days after the operation the number of eggs showing normal cleavage decreased to zero. Ova that were fertilized implanted normally and survived gestation without effects on sex ratio or morphology. Significant improvements in embryonic survival rate were seen before failure of fertilization (p less than .001) possibly because the older spermatozoa may be the first to lose their fertilizing competence.

Acid-soluble phosphorus compounds in mammalian semen.

Abstract: 1. A method is described for the extraction, purification and separation of acid-soluble phosphorus compounds from mammalian semen. [8-14C]ATP and [8-14C]AMP were used as internal recovery standards to measure the breakdown and loss of these nucleotides in the procedure. 2. Bull, ram, boar and stallion semen was separated into seminal plasma and spermatozoa and the two fractions were examined separately. The overall composition of the mixture of the phosphorus compounds extracted from the two fractions was similar for the four species. 3. Glycerylphosphorylcholine and glycerylphosphorylinositol were the two phosphorus compounds identified in extracts of seminal plasma. ATP, ADP, AMP, GTP, GDP, NAD, fructose 1,6-diphosphate and glucose 6-phosphate were identified in extracts prepared from spermatozoa.

Inhibition of Fertilization in Rabbits During Treatment with Progesterone

Abstract: Adult female rabbits (Dutch strain) were artificially inseminated with 0.5 ml of diluted semen (10 X 106 to 40 X 106 spermatozoa) and ovulated with 100 to 200 IU of HCG. Corn oilor progesterone in corn oilwas injecteddailysubcutaneously for various periods, ranging from 0 to 6 days before insemination and continuing untilsacrifice48 hr after insemination. Fertilizationof ova was inhibited when 1 mg progesterone was injected daily for 2 or 6 days before insemination but not when the treatment began on the day of insemination or 4 days before insemination. An increasein the transport rate of ova occurred only when treatment was initiated 2 days before insemination. The fertilizationinhibitory response to progesterone was dose dependent between doses of 0.05 and 4 mg/day and the ED50 was 0.4 mg. Although none of the levelsemployed was 100% effective,only 2% of the ova recovered from the group given 4 mg/day were fertilized. A sperm index with values ranging from 0 to 3 was employed to indicate the total number of sperm counted in the mucin layer, zona pellucida, or perivitelline space of ova. Values in all three areas were low in ova recovered from animals given 0.5 mg progesterone/day and were reduced to 0 or near zero with all higher doses. When semen was deposited into the uterus of animals given 1 mg progesterone/day for 6 days, nearly all ova were fertilized. In animals given 1 mg progesterone/day, an increase in the semen concentration from 10 to 100% failed to significantly increase the percentage of ova fertilized, but successive injections of 50 U.S.P. units of oxytocin 1 hr before insemination and 1 and 4 hr afterwards increased the percentage of ova fertilized from 0 to 45% and increased the sperm index values approximately 50% in each of the layers of the ovum. Spermatozoa were recovered from the cervix and serial segments of the uterus and oviducts at 4, 8, 16, and 24 hr following insemination; they were counted using a micropore filtration technique. The numbers of sperm in all segments of the uterus and oviducts of the progesterone-treated animals were consistently less than in corresponding segments of control organs; they were absent from the anterior 2/3 of the oviduct until 16 hr after insemination at which time only a few in the middle oviducal segment were found. Progesterone inhibited fertilization of ova, we conclude, primarily by interference with sperm transport mechanisms in the uterus and/or oviduct.

Use of polynucleotides with seminal antigens to induce isoantibodies and infertility in rabbits.

Abstract: SummaryInjections of female rabbits with homologous seminal antigens in combination with polyadenylic and polyuridylic acids (0.4-0.5 mg of each per injection) induced antifertility effects and serum titers of specific antibodies. Rabbits immunized with seminal plasma had normal fertility, whereas rabbits immunized with semen and epididymal sperm showed fertilization inhibition after artificial insemination and low embryo and fetal survival after embryo transfer. Immunization with semen induced high serum titers of specific antibodies as determined by passive hemagglutination, sperm agglutination, and sperm immobilization. Epididymal sperm caused moderate hemagglutination titers and high titers of sperm-agglutinating and immobilizing antibodies, whereas seminal plasma induced high hemagglutination titers but low sperm-agglutination titers, and no immobilizing antibody. Sperm-agglutinating and immobilizing titers were highly correlated in rabbits immunized with semen and epididymal sperm.

Electrophoretic and gel filtration behaviour of boar seminal plasma proteins before and after removal of accessory sex glands.

Abstract: The origins of the major proteins of boar seminal plasma were identified using starch gel electrophoresis, gel filtration on Sephadex G-200 and surgical removal of various accessory sex glands. Seminal vesicular secretion accounted for all the major proteins in seminal plasma which migrated to the cathode. Bulbo-urethral proteins could not be detected electrophoretically or by gel filtration. Prostatic\x=req-\ urethral fluid contained at least one protein which migrated to the anode and was not ofserum origin. Secretions from the epididymis and/or testis contained at least two proteins which migrated to the anode that were eventually voided in the seminal plasma of the ejaculate. Boar seminal plasma separated on Sephadex G-200 into three major peaks corresponding to molecular weights of approximately 155,000 (Peak B), 55,000 (Peak A) and 34,000 (Peak C). Peak A proteins were primarilyofseminal vesicular origin, while Peak B proteins were primarily of epididymal or testicular origin. Peak C consisted of proteins from all regions of the reproductive tract. Haemagglutinating activity was located between Peaks A and B, associated with molecules of approximately 68,000 molecular weight, and was absent after removal of the seminal vesicles.

The relationship between numbers of spermatozoa inseminated and fertilization rate of ova in ewes treated with fluoro-progestagen intravaginal sponges in summer and autumn

Abstract: Two experiments were conducted, during December and March, designed primarily to determine the oestrous response and fertilization rate following the insemination of varying numbers of spermatozoa in ewes treated with intravaginal sponges impregnated with Cronolone, a synthetic progestagen. The main results were: Incidence of oestrus: December; (a) treated ewes, 45\\m=.\\7%;(b) untreated teased ewes, 47\\m=.\\5%;(c) untreated non-teased ewes, 30\\m=.\\0%; March; (d) treated ewes, 94\\m=.\\8%(a versus b, NS; a versus c, P < 0\\m=.\\01;

The effects of scrotal heating in the ram on semen characteristics, fecundity, and embryonic mortality.

Abstract: In three experiments the testes of rams were heated to 40.5¦C for either 1.5 hr or 2 hr, or to 39.5¦C for 4 hr; the effect on the number of spermatozoa in the ejaculate and the proportion of these that were dead or tailless was examined over the subsequent 60 days. The fecundity of the rams was tested over the same period and compared with that of the unheated rams, a total of 396 ewes being used. Spermatozoa present in the epididymis at the time of heating appeared to be unaffected, but there was considerable damage to spermatozoa developing in the testes. This was manifested by increased proportions of dead and of tailless spermatozoa between days 14 and 50 (day 0 = day of heating). In rams whose testes were heated to 40.5¦C there was also a marked depression in the number of spermatozoa per ejaculate between days 34 and 47, and their fecundity was low between days 14 and 34 and was zero between days 34 and 47. Embryonic losses were estimated by comparing the number of eggs fertilized (in ewes 2 days post coitum) with the number of embryos present in ewes examined 37-42 days post coitum. In only one of the three experiments was there a significantly increased loss of embryos in ewes mated to heat-treated rams. It is concluded that, in ewes mated to heat-treated rams, embryonic losses are of minor importance compared with losses due to non-fertilization.

Oxygen Consumption of Human Semen

Abstract: 15) and from men with prostatovesiculitis 1.4 �l 02/108 live cells/hr (SD ± 2.5, range 0-8.2; n = 13). The difference was significant (0.01 > p > 0.005). No significant difference was noted between the oxygen consumption of the spermatozoa in specimens from patients with decreased secretory function of the prostate gland (n = 13) or with asthenospermia (n = 25) compared with that in specimens from the healthy subjects. No correlation was found between oxygen consumption of the spermatozoa and various biochemical parameters of the seminal plasma, such as zinc, magnesium, fructose, LDH, and MDH. The mean oxygen consumption of the seminal plasma was 4.4 ,�l 0,/mI/hr (so ± 1.3, range 1.9-6.0; ii = 79). There was no significant difference between samples from the different groups of men.

Zinc and magnesium in human seminal plasma

Abstract: Several hundreds of specimens of human seminal plasma have been analyzed for zinc, magnesium, acid phosphatase activity, cholesterol and fructose. The semen was also analyzed for sperm density, motility, viability and morphology. The mean concentrations of zinc and magnesium were 129 and 106 μg per ml, respectively. Zinc and magnesium concentrations were correlated (r=0.84) and both ions appear suitable for evaluation of the secretory activity of the prostate gland. Three out of four semen samples with less than 50 μg Zn and/or Mg per ml had pathological spermiograms compared to 40 per cent among those with more than 100 μg/ml.