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T Reilas

Publications and source records attributed to T Reilas.

9 recordsLinked to original sources
PubMed2006

Effect of seminal plasma fractions on stallion sperm survival after cooled storage.

This study aimed to evaluate stallion sperm survival after 24 h of cooled storage in the presence of seminal plasma (SP) derived from the sperm-rich fractions (SRF) or sperm-poor fractions(SPF) of the ejaculate, without SP, or in the presence of SP from other stallions. Ejaculates were collected from four stallions using an automated phantom, which separated the semen into five cups. Centrifuged and washed spermatozoa from cup 2 (SRF) were mixed with skim milk extender to a concentration of 100 x 10(6) sperm/ml and then 1:1 (v/v) with SP from the stallion's own or another stallions' second (SP-SRF) or last cup (SP-SPF). Skim milk extender (K) and skim milk extender supplemented with modified Tyrode's medium (KMT) were used as control treatments. After a 24-h storage period in a transport container, spermatozoa were evaluated for motion characteristics and plasma membrane integrity by calcein acetoxymethyl (AM)/propidium iodide staining. The percentage of spermatozoa with intact plasma membranes after storage was lower in SP-SRF than in SP-SPF, and the highest in K (P < 0.05). Progressive motility (PMOT) was lower for sperm stored in SP-SRF than for sperm stored in SP-SPF (P < 0.05), but there was no significant difference in total motility (TMOT). Sperm stored in KMT (P < 0.05) registered the highest TMOT and PMOT percentages. Osmolarity was significantly higher and pH lower in K than in KMT or SP. Treatment with SP-SPF from three stallions benefited the PMOT of sperm from one stallion. These preliminary findings suggest that SP from SRFs may be more harmful during storage than SP from SPFs. Removal of SP improves sperm survival in KMT extender, and exchanging SP between stallions seems to influence sperm survival.

Animals↗
PubMed2006

Motility and plasma membrane integrity of spermatozoa in fractionated stallion ejaculates after storage.

With the aim of investigating properties of stallion seminal plasma to eventually improve semen-handling techniques, sperm motility and plasma membrane integrity were analysed in different fractions of the ejaculates after storage. Semen was collected using a computer-controlled automated phantom that separates the ejaculates into five successive cups. Samples containing seminal plasma and skim milk extender were compared with samples stored in skim milk extender after the removal of seminal plasma by centrifugation. Fractionated ejaculates were stored cooled for 24 h after dilution with extender (Expt 1) or frozen in liquid nitrogen (Expt 2). In Expt 1, cup 1 was pre-sperm fluid, cups 2 and 3 sperm-rich fractions, and cup 4 sperm-poor fractions. In Expt 2, cups 1 and 2 were sperm-rich fractions, and cups 3 and 4 sperm-poor fractions. One sample (WE) represented the whole ejaculate in both experiments. Motility parameters were determined with a Hamilton-Thorn Motility Analyzer, and plasma membrane integrity was assessed using carboxyfluorescein diacetate and propidium iodide staining and fluorescence microscopy. The removal of seminal plasma lowered motility values, but not plasma membrane integrity, in both experiments. No significant differences between cups were observed after cooled storage. The cups differed significantly in most post-thaw motility parameters, and the sperm-rich fraction showed higher post-thaw motility than the whole ejaculate.

Animals↗
PubMed2005

Effect of insemination volume on uterine contractions and inflammatory response and on elimination of semen in the mare uterus-scintigraphic and ultrasonographic studies.

The effect of artificial insemination (AI) volume on uterine contractility and inflammation and on elimination of semen in the reproductive tract of mares was examined for 4 h after AI using two methods, scintigraphy and ultrasonography. The same doses were used in both methods: 2 and 100 ml of skim milk-extended frozen semen. In the scintigraphic study, the number of reproductively normal mares was four per group and in the ultrasonographic study five per group. For scintigraphy, the semen was radiolabelled with technetium-99m. The static scintigrams were acquired immediately before and 30, 60, 120, 180 and 240 min after AI. The activities in the vagina and uterus were calculated and the values for sperm that had been discharged from the mare were obtained by subtracting the counts for the uterus and vagina from the total radioactivity. The dynamic scintigrams were taken continuously for the first 30 min after AI and in 5-min periods immediately after having acquired the static scintigrams. The uterine contractions were counted. In the ultrasonographic study, the mares were scanned before AI and at 5, 10, 15, 20, 25, 30, 60, 120, 150, 180, and 240 min after AI, for at least 1 min each time. The examinations were videotaped and contractions counted per minute. More contractions were observed with the ultrasonographic method than with the scintigraphic method. No difference was present in the number of contractions between the groups, except in the ultrasonographic study at 4 h, when the mares inseminated with 100 ml showed more contractions than did the mares inseminated with 2 ml. The intraluminal fluid was sampled with a tampon and by uterine lavage 4 h after AI in the ultrasonographic study. The numbers of polymorphonuclear leukocytes and spermatozoa were counted, but the differences between the groups were not significant. Under our experimental conditions and with the number of mares examined, the volume of the AI dose had an insignificant effect on contractility - with the exception at 4 h - and inflammatory reaction and on semen elimination in the uterus.

Animals↗
PubMed2005

Effect of seminal plasma on uterine inflammation, contractility and pregnancy rates in mares.

REASONS FOR PERFORMING STUDY: There is conflicting evidence over the role seminal plasma plays in sperm transport and inflammation within the uterus of mares. In in vitro studies, seminal plasma has been shown to reduce polymorphonuclear neutrophil (PMN) function, but the opposite effect on uterine inflammation has been reported in vivo. OBJECTIVES: To study the effect of seminal plasma on uterine contractility, inflammation and pregnancy rates by inseminating mares with low doses of sperm free from seminal plasma (Group 1) and containing seminal plasma (Group 2). METHODS: Synchronised mares were inseminated with 50 x 10(6) sperm in either skim milk extender or seminal plasma. Uterine lavage was performed 6 h after insemination to assess the inflammatory response. The contraction frequency of the uterus was measured over a 4 min period 10 mins and 6 h after insemination, using B-mode ultrasonography. Pregnancy rates were assessed 16 days after insemination. RESULTS: Uterine contractions were less frequent in Group 1 mares inseminated with seminal plasma and significantly more PMNs were found in the lavage fluid of those mares. Pregnancy rates were identical in both groups (62%). CONCLUSIONS: This study provides evidence that seminal plasma decreases uterine contractility and increases the inflammatory response of the uterus to semen. No effect of seminal plasma on pregnancy rates was demonstrated. POTENTIAL RELEVANCE: Mares that develop persistent mating-induced endometritis may have inherently poor uterine contractility and impaired uterine clearance. The presence of seminal plasma during breeding may not be desirable in these mares. The role of seminal plasma in problem mares warrants additional study.

Animals↗
PubMed2002

Proteins and enzymes in uterine lavage fluid of postpartum and nonparturient mares.

Uterine lavage fluids from postpartum and nonparturient mares were compared to determine when the normal secretory capacity of the postpartum uterus is restored. Lavage fluids were obtained from cyclic nonparturient mares on the second, fourth or fifth day of oestrus, and 3, 8, or 14 days after ovulation (seven mares/sampling day). Twelve intact postpartum mares were sampled 1 to 28 days postpartum (group A: 1, 6, 12 and 20; group B: 2, 8, 14 and 24; group C: 4, 10, 16 and 28 days postpartum; four mares/group). Three ovariectomized (OVX) postpartum mares were sampled as mares in group C. Samples were analysed for neutrophils, bacteria, total protein concentration, proteolytic and antiproteolytic activities and for various lysosomal enzyme activities. In nonparturient mares, activities of acid phosphatase, beta-glucuronidase (B-Gase), and N-acetyl-beta-D-glucosaminidase (NAGase) in uterine lavage fluids were significantly higher in mid- and late-dioestrus than in mid- to late-oestrus (p < 0.05). Lysozyme concentration, trypsin-inhibitor capacity (TIC), and plasmin activity were below the detection limit in nonparturient mares. One to four days postpartum, total protein, acid phosphatase, B-Gase, and NAGase were high but declined rapidly thereafter. Lysozyme and plasmin activities were high 1 to 6 days postpartum. TIC peaked around day 6 postpartum. On day 16 postpartum, acid phosphatase, B-Gase, and NAGase, being progesterone-dependent, tended to be higher in intact mares than in OVX ones (p < 0.1). Total protein and lysozyme concentrations, TIC, and B-Gase (p < 0.01) and acid phosphatase (p < 0.05) activities were significantly higher in parturient mares during postpartum oestrus than in oestrous nonparturient mares. High total protein concentration and TIC, and detectable lysozyme and plasmin activities during postpartum oestrus were associated with uterine inflammation. During dioestrus, differences between postpartum and nonparturient mares were not statistically significant and suggested that the endometrium of postpartum mares had resumed its normal secretory capacity by this time.

Acetylglucosaminidase↗
PubMed1997

Intrauterine fluid accumulation in oestrous mares.

Intrauterine fluid (IUF) was collected using a tampon from mid-oestrous mares (n = 57) with and without ultrasonically detectable accumulations of free intraluminal fluid. Bacteria were cultured and neutrophils counted from all samples (n = 57). Total protein concentration, trypsin-inhibitor capacity (TIC), and plasmin, beta-glucuronidase (B-Gase) and N-acetyl-beta-D-glucosaminidase (NAGase) activities were determined in 27 IUF samples. The motility of spermatozoa in the presence of IUF, IUF extended with Kenney's medium (1:1) and Kenney's medium alone was analysed in 9 samples using a Hamilton-Thorn motility analyser. Thirty-five mares were inseminated immediately after collection of IUF, and every second day until ovulation. Embryos were recovered nonsurgically 6 days after ovulation. After embryo transfer, fluid accumulations were recorded during oestrus and an endometrial biopsy specimen taken (n = 53). In the beginning of oestrus, fluid accumulations were detected in 39% (22/57) of mares, while on the day when IUF was collected, fluid accumulations were observed in 26% (15/57) of mares. The fluid was anechogenic, and in 80% of the mares located in the uterine body. None of the mares exhibited cytological or bacteriological evidence of acute endometritis. Total protein concentrations, TIC and B-Gase activities in IUF were statistically significantly lower in mares with fluid accumulations (n = 14) than in mares without fluid accumulations (n = 13) (p < 0.01). The addition of undiluted IUF to extended semen significantly reduced total and progressive motilities, path velocities and percentages of rapid spermatozoa (p < 0.05) in vitro. On endometrial biopsy, fibrosis was found to be more prominent (p = 0.025) in mares with fluid accumulations (n = 9) than in mares without (n = 44). It was concluded that anechogenic fluid accumulations during oestrus were associated with compositional changes in IUF. Although IUF had negative effects on spermatozoal motility in vitro, the presence of fluid accumulations at the time of insemination did not affect embryo recovery rates.

Acetylglucosaminidase↗
PubMed1996

Recovery rate and quality of embryos from mares inseminated at the first post-partum oestrus.

The pregnancy rate is lower in mares inseminated at the first post-partum (p.p.) oestrus (40-50%) compared with pregnancy rates in subsequent oestrous cycles (55-65%). The causes of the lowered pregnancy rate are not fully understood. The aim of the present study was to examine if embryonic defects could be one of the reasons for lowered pregnancy rate. A total of 23 p.p. and 14 non-lactating control mares were flushed 7 days after detection of ovulation. Embryo recovery rate was 48% and 71% in p.p. and control mares, respectively (p = 0.16). Embryos were photographed, measured, graded and stained with fluorescein diacetate to assess their viability. Thereafter embryos were bisected and stained with Hoechst 33342 to count the cell nuclei. Embryos in both groups were equally viable and the cell numbers were not significantly different. According to morphological evaluation all embryos were classified as excellent or good. Embryos aged 7.3 to 7.6 days (+/-0.25 days) were smaller in the p.p. group than in the control group (p < 0.05). Forty-seven (9/19) and 8% (1/13) of the uterine swabs, taken before the first insemination, yielded bacteria and neutrophils in p.p. and control mares, respectively. The amount of neutrophils and/or bacteria had no statistically significant effect on embryo recovery rate (p > 0.10). Recovery of embryos was not related to histological findings in uterine biopsies taken after embryo recovery. Embryo recovery rate in p.p. mares (48%) was similar to previously reported foal heat pregnancy rates (40-50%). Hence, early embryonic death in utero would not be the most likely reason for lowered pregnancy rate in mares inseminated at the first p.p. oestrus. Sperm transport and oviductal conditions by the time of the first p.p. oestrus would need to be studied to clarify the role of fertilisation failure as the cause of lower pregnancy rate in mares inseminated at foal heat.

Animals↗
PubMedDate not supplied

Relationship between embryo recovery rate and uterine lavage fluid composition in postpartum mares.

The aim of the study was to determine whether neutrophil numbers (PMN), trypsin-inhibitor capacity (TIC), lysozyme, N-acetyl-beta-D-glucosaminidase (NAGase), beta-glucuronidase (B-Gase), total protein, and plasmin in uterine lavage fluid of postpartum (p.p.) mares, either at the time of foal heat insemination or around the time of arrival of the embryo in the uterus, could be used in predicting conception. Fifteen mares were inseminated within 13 h after the first p.p. ovulation. Uterine lavage fluids were successfully collected from 9 out of 12 mares before insemination and from all 15 mares before embryo recovery 7 to 8 days after insemination. The embryo recovery rate was 53% (8/15). Prior to insemination, PMN, TIC and lysozyme levels were elevated in 3/4 mares not producing embryos. However, only 1/5, 1/5 and 0/5 mares producing embryos had elevated levels of PMN, TIC, and lysozyme, respectively. None of the parameters was significantly different in mares with or without embryos, but lysozyme was the closest to significance (p = 0.07). In both groups of mares, activities of NAGase (p < 0.01) and B-Gase (p < 0.05) were significantly higher in dioestrus than immediately after ovulation. At embryo recovery, NAGase was higher in mares not producing embryos (p < 0.05). The results suggest that a long-lasting inflammation is the best explanation for low pregnancy rates during the first p.p. oestrus. Further research is needed to establish whether lysozyme, or possibly TIC, could be used in predicting conception at foal heat.

Acetylglucosaminidase↗