Finnie A. Murray

Effect of in vitro selenium supplementation on bovine sperm motility

The effects of selenium (Se) on motility of bovine spermatozoa were evaluated in two experiments. In Experiment 1, increasing doses of Se alone or with vitamin E were found to increase motility in Se concentrations up to 1 mug/ml. However, Se alone had a greater effect than did Se with vitamin E. The sperm motility response to Se concentrations from background to 1 mug/ml on motility best fit a quadratic equation with a maximum at about .65 mug Se/ml. In Experiment 2, the effect of Se addition before and after freezing was evaluated. This experiment demonstrated that treatment of semen with Se before freezing significantly increased the post-thaw motility as compared with portions of the same ejaculate which were not treated. Treatment after thawing produced motilities which were intermediate and not significantly different from either pre-freezing supplementation or no supplementation at all. These data indicate that some semen exhibits a greater percentage of motile sperm when Se is added prior to freezing, however, no information is yet available on the fertility of Se-treated semen.

Immunosuppression in the Mouse by Porcine Uterine Secretory Protein

ABSTRACT: Experiments were performed to determine whether uterine secretory proteins (PAP) of the pig affect T cell or B cell functions in vivo. T cell functions examined were E‐rosette formation (ERF) and cutaneous reactivity (to phytohemagglutinin) in mature BALB/c females. Two ERF experiments of identical design were performed using five groups of ten mice each. Each mouse was presensitized with sheep erythrocytes (SRBC) designated as day 0; and the various groups were treated with saline, pig serum (PS), or PAP at different times. For cutaneous reactivity, the area of erythema at the sensitization site (pinnea of ear) was measured, and three groups of 11 mice were used. These groups also received either PS or PAP. B cell function was examined by measurements of hemagglutination titers to SRBC sensitization in BALB/c females treated in two experiments similar to the ERF. T cell functions examined were highly suppressed (p < 0.01) by PAP given hours, not days, prior to the measurement. The B cell function examined was not affected by PAP.

Effects of selenium supplementation on bull sperm metabolism in vitro

An in vitro study was conducted to examine the effects of direct supplementation of diluted semen with sodium selenite on the metabolism of bovine sperm. Selenium (Se) supplementation increased the percent motility yet did not affect the percent viability of the sperm. An increase in the oxygen consumed by the sperm was associated with the increase in sperm motility. Both the adenosine triphosphate (ATP) and total adenyl nucleotide (TN) concentrations were lowered by supplementing the sperm with Se. Although changes occurred in the adenyl nucleotide pool of the Se-supplemented sperm, these changes were not reflected in the energy charge. There was no difference in the energy charge between the Se-supplemented and unsupplemented sperm. The metabolic changes caused by Se were in vitro and occurred in a short interval of time, suggesting a catalytic effect as opposed to an enzymatic effect.

Partial purification of uterine secretory protein capable of suppressing lymphocyte reactivity

Porcine uterine flushings obtained on day 15 of the estrous cycle were fractionated using gel filtration, and preparative poly-acrylamide gel electrophoresis was employed to separate one molecular weight fraction into two groups of small uterine-specific proteins designated pAP and pLAP. The two groups were assayed for immuno-suppressive ability using phytohemagglutinin (PHA) stimulated porcine lymphocyte cultures and incorporated 3H-thymidine. It was found that the pAP preparation which was composed of two proteins inhibited lymphocyte reactivity to PHA (p<.001) while the pLAP preparation failed to exhibit a similar activity at levels as high as 1000 μg/ml. The immunosuppressive effect was determined to be independent of cytotoxicity, PHA inactivation by binding and other non-specific phenomena. The results of this study indicate that the immunosuppressive activity of porcine uterine flushings is caused, at least in part, by one or both of these proteins present in the pAP preparation.

Suppression of lymphocyte reactivity in vitro by porcine allantoic and amniotic fluids.

Porcine allantoic and amniotic fluids from early, mid and late pregnancy were analyzed for protein constituents and ability to suppress phytohemagglutinin (PHA)-induced lymphocyte transformation. All fetal fluids contained alpha-fetoprotein as evaluated by polyacrylamide gel electrophoresis (PAGE), with the highest concentrations appearing in mid-pregnancy amniotic fluids. In addition, allantoic fluids from mid-pregnancy contained proteins assumed to be secreted by the uterus. Both allantoic and amniotic fluids from mid-pregnancy were suppressive to PHA-induced lymphocyte transformation (P<.01). Thus it was concluded that substances, potentially able to suppress the immune response locally, exist within porcine fetal fluids, but it was not determined whether this material is of solely fetal or maternal origin, or a combination.