Changes in proacrosin levels during preservation of ram semen

The percentual change in the content of pro-acrosin taking place in ram semen preserved for a short and long time was examined in the period from April to October. Two diluents for keeping semen at the temperature of 16 degrees C and one diluent for keeping semen at 3 to 4 degrees C were used in short-time preservation. The content of pro-acrosin was measured 2, 8 and 12 hours after dilution. The lactoso-yolk diluent and the diluent after Milovanov (1980) were used for cryopreservation. The content of pro-acrosin was examined before and after semen freezing. In short-time preservation, no statistically significant decrease of pro-acrosin content was demonstrated in the H Milch diluent (Peter, 1975) at the storage temperature of 16 degrees C and in the diluent after Milovanov (1980) at the temperature of 3 to 4 degrees C. In the diluent prepared after Milovanov (1980) a significant decrease of pro-acrosin content during preservation was recorded at the storage temperature of 16 degrees C. When the short-time preservation diluents were compared, significant differences in pro-acrosin content were found between them. In the long-time preservation diluents a significant difference in pro-acrosin content was found before and after semen freezing; the difference between the short- and long-time preservation diluents was also significant. A positive correlation was found between sperm activity and pro-acrosin content.     

抗氧化剂在哺乳动物精液冷冻保存中的应用

从20世纪50年代哺乳动物精液冷冻研究开始,国内外研究者通过几十年对精液冷冻程序以及冷冻稀释液、解冻液等的筛选,牛、羊等家畜的冷冻精液已经商业化生产,广泛用于人工授精进行优良品种的繁殖.     

Effects of seasons on some semen parameters and bacterial contamination of Awassi ram semen

The objectives of the present study were to determine the effects of season on some semen parameters and bacterial contamination of Awassi ram semen. Semen samples from six mature Awassi rams were used in this study. Semen collection was performed with artificial vagina every week, from September 2009 to October 2010. Volume, sperm concentration, mass motility, individual motility, percentage live sperm and sperm abnormalities were evaluated. Moreover, determination of viable bacterial count of the rams was also recorded weekly. Higher (p < 0.05) semen volume in the hot summer and spring months was observed of August (1.55 ± 0.08 ml) and March (1.27 ± 0.15 ml). Sperm concentration was highest (p < 0.05) in the breeding season (late summer to early autumn) of September (4.21 ± 0.86 × 10(9) sperm/ml). Sperm individual motility and percent of live sperm observed in August (summer) and May (end of spring) when the environmental temperature started to increase were recorded highest values and differed significantly (p < 0.05) from December and January (winter). The highest value of the mean sperm acrosomal defects (13.33 ± 0.63%) was recorded in December. The highest value of the mean viable bacterial count (138.3 ± 21.6) was recorded in July (summer). A significant decrease (p < 0.01) in the mean viable bacterial count was observed from the middle of winter towards the end of spring. The lowest bacterial count was noted in January (60.5 ± 2.98). It could be concluded from the results of the present study that there is an effect of season on ram semen quality, and summer high temperature in northern Iraq has no effect on Awassi ram semen. There is a significant effect of season on bacterial count on Awassi ram semen.     

Kisspeptin injection improved the semen characteristics and sperm rheotaxis in Ossimi ram

The aim of the present study was to investigate the effect of kisspeptin-10 (Kp10) injection on semen characteristics, testosterone (T) production and sperm rheotaxis using microfluidic devices in immature ram. Computer-assisted sperm analysis (CASA) with controlled flow velocity was used to explore the kinetic parameters of sperm and positive rheotaxis (PR %). PR % was defined as the number of PR sperms over the number of motile sperms. Healthy Ossimi rams were randomly divided into two groups; a saline-treated control group and Kp10-treated one (5 µg/kg body weight). Treatments were given by intramuscular injection once a week for 1 month. After 1 month, the semen was collected and evaluated weekly for 6 weeks, while the blood samples were collected every 2 weeks for the next 8 weeks. Semen properties were significantly affected by Kp10 injection (p < .01). The Kp10 increased the volume, sperm concentration and percentages of live sperm compared with those of control. Additionally, sperm trajectories and rheotaxis get improved by the injection of Kp10 with time. Furthermore, kisspeptin improved the secretion of testosterone levels throughout the period of study. In conclusion, injections of the Kp10 had a positive impact on semen characteristics as well as improved sperm rheotaxis of Ossimi rams in subtropics.     

抗氧化剂在猪精液冷冻保存中的作用

随着冷冻精液技术的发展,抗氧化剂作为精液稀释液中必不可少的一类成分,在降低精子的氧化损伤、提高精子活力质量上起到了关键的作用。文章对近些年来国内科研团队所使用的抗氧化剂进行综述,总结其对精液品质提升改善的能力,为猪精液冷冻技术的发展提供理论依据和参考。     

Effect of selenium supplementation on semen characteristics of Brazil's ram

The aim of this study was to investigate the effects of different concentrations of oral supplementation with selenium (Se) upon ram sperm parameters. Thirty rams managed in stall under intensive system were used and divided into five groups (six animals per group) as follows: control group (G1) mineral mixture supplementation without Se, group 2 (G2) mineral mixture supplemented with 5 mg/kg Se, group 3 (G3) supplemented with 10 mg/kg Se, group 4 (G4) supplemented with 15 mg/kg Se and group 5 (G5) supplemented with 20 mg/kg Se. For each group, there was an adjustment period of 14 days. The experimental period was 350 days. Every 56 days, the animals were weighed and semen samples were collected by electroejaculation. Semen analysis included volume, mass moviment, total motility, vigour, concentration and morphology. For plasmatic and acrosomal membrane integrity evaluation and mitochondrial membrane potential were used a combination of fluorescent probes. Differences between means values obtained by analysis of variance were verified by Tukey test with 5% probability. There was no statistical difference between treatment groups in relation to volume, mass moviment, total motility, vigour, concentration, plasma and acrosomal membrane integrity (p > .05). Sperm morphology was different between treatment groups, the G1 (0 mg of selenium) had the highest percentage of major defects (11.11 ± 1.11^a; p < .05). It was concluded that selenium decrease the percentage of sperm defects and did not directly influence on ram sperm volume, mass moviment, total motility, vigour, concentration and membrane integrity.     

A comparison of electro-ejaculation with the artificial vagina for ram semen collection

Nine fertile three-year-old Romney rams were ejaculated both by means of electro-ejaculation and by the artificial vagina. The ram repeatabilities of semen volume, concentration, total sperm number, percentage normal sperm and wave motion score of ejaculates collected by electro-ejaculation were 0.17, 0.08, 0.12, 0.61 and 0.23 respectively compared with the repeatabilities of ejaculates collected by the artificial vagina of 0.28,0.79, 0.56,0.72 and 0.54. The repeatability results showed that it was possible to rank rams on the quantity of sperm produced in a single ejaculate obtained by an artificial vagina, but not on the quantity obtained by electro-ejaculation. The correlation co-efficients between the ram means for the two techniques were for volume 0.05, concentration 0.06, total sperm number -0.21, percentage normal sperm 0.73, and wave motion score 0.35. Only the percentage normal sperm coefficient was significant.     

Sperm viability in ram semen diluted and stored in three different extenders.

Semen was collected with an artificial vagina from 4 one-year-old rams, in order to study the changes in sperm motility and membrane integrity of spermatozoa split-diluted and stored at 5 degrees C during 7 days in sodium citrate, Tris, and milk-based extenders, respectively. Sperm motility was assessed subjectively and sperm membrane integrity was determined using the fluorescent probes Calcein-AM and Ethidium homodimer. Representative samples were studied using scanning electron microscopy (SEM). The average incidence of sperm motility decreased over time in all the extenders (p < 0.001). The incidence of spermatozoa showing progressive motility and intact plasma membrane was significantly higher in semen diluted with sodium citrate than in the other 2 extenders following 4 days of dilution until the end of the study. Evaluation with SEM confirmed the findings obtained with the supra vital fluorescent dyes. The results of the present study indicated that there were no differences between sodium citrate-, Tris- or milk-based extenders when ovine liquid semen was stored at 5 degrees C during a short period (2 days). However, when semen was stored for longer time, spermatozoa in the sodium citrate-based extender sustained its viability better.     

用澳洲美利奴种公羊细管冻精改良当地绵羊试验效果

为了提高五大连池市绵羊的生产性能,解决绵羊种公羊短缺、种质差、近亲繁殖等问题,从1998年引进澳洲美利奴种公羊的细管冻精改良当地绵羊,近几年来,改良效果明显,现将试验效果报告如下。     

浅析抗氧化剂对猪精液保存的影响因素

近年来,随着畜牧业的发展,家畜精液保存技术在生产实践中发挥着重要作用。在精液保存过程中,体内外环境的差异打破了精子所处环境的动态平衡,保存期间产生大量的活性氧（reactive oxygen species,ROS）。过量的ROS会与精子质膜发生氧化反应,破坏精子的功能和结构完整性,使其活力和质量降低,影响受胎率。为了降低ROS对精液的损伤,加入外源抗氧化剂可以有效抑制和清除ROS,避免精子细胞受到破坏,进而提高精液品质。文章对抗氧化剂的作用机制、抗氧化剂的种类以及在猪精液保存上的应用等方面进行综述。     

后备配种条件对托佩克大白猪首胎繁殖成绩的影响

文章通过分析托佩克大白头胎母猪初配日龄、体重、背膘和分娩前体重、背膘以及妊娠期间背膘和体重的变化与首胎繁殖成绩的关系发现,托佩克大白猪繁殖最佳条件为:配种日龄为239～245日龄,配种体重为150～160 kg,妊娠期间体重增加88～95 kg,分娩前体重为240～250 kg,配种背膘为14～20 mm,妊娠期间背膘...     

Multiplex PCR for the detection of Brucella ovis, Actinobacillus seminis and Histophilus somni in ram semen

OBJECTIVE: To develop a multiplex polymerase chain reaction (PCR) assay for the rapid detection of Brucella ovis, Actinobacillus seminis, Histophilus somni in fresh ram semen samples. DESIGN: The multiplex assay was based on the single PCR assays published for the detection of A seminis and B ovis, and the forward primer published for the detection of H somni; an alternative reverse primer for H somni was designed in this study. PROCEDURE: Culture and PCR of 295 fresh semen samples were carried out. RESULTS: The multiplex PCR was far more successful in the detection of H somni (45/295) than culture (23/295). A seminis was also detected in more semen samples by multiplex PCR (29/295) than culture (13/295) and B ovis was detected in three samples using both PCR and culture. No amplifications were detected with DNA from a range of bacterial isolates including species associated with epididymitis in rams. CONCLUSION: This PCR could be used as a complementary test, or alternative to culture of ram semen and other biological samples for the detection B ovis, H somni and A seminis.     

Effect of heterologous seminal plasma and semen extenders on motility of frozen-thawed ram spermatozoa

Ram seminal plasma increases the fertility of frozen-thawed ram spermatozoa deposited into the cervix. The aim of the current study was to compare the effect of ram seminal plasma to that of bull seminal plasma, dog prostatic fluid, protein-free TALP TrilEq (Triladyl with 0.5 mt of Equex STM paste added to each 100 mt) and heat-treated skim milk on longevity and percentages of progressively motile and aberrantly motile frozen-thawed ram spermatozoa. Three ejaculates from each of 6 rams were extended in TrilEq, pooled and frozen in straws as a single batch per ram. One hundred and eight straws (3 straws from each ram for each fluid) were thawed in random order. Once thawed, a straw was emptied into a tube with 0.85 ml of the appropriate fluid at 37 degrees C and kept at that temperature for 6 h. Motility was assessed at x200 magnification immediately (time zero) and 2, 4 and 6 h after thawing. Progressive motility decreased from each time to the next (P < 0.05) and was 39.0 % (0 h), 26.0 % (2 h), 19.6 % (4 h) and 12.6 % (6 h); SEM 1.24, n = 108 for each group. Ram seminal plasma resulted in higher progressive motility than bull seminal plasma, lower than milk, and similar to the other fluids. Ram seminal plasma resulted in lower aberrant motility than protein-free TALP and similar aberrant motility to other fluids. The effect of ram seminal plasma and dog prostatic fluid was very similar. The effect of ram seminal plasma on the fertility of frozen-thawed ram spermatozoa deposited into the cervix is not due an exceptionally beneficial effect on the motility of spermatozoa.     

Cryopreservation of ram semen: Manual versus programmable freezing and different lengths of equilibration

The aim of our study was to examine effects of the length of semen equilibration as well as two freezing techniques on ram sperm post-thaw quality. The ejaculates of Wallachian sheep rams (n = 12) were collected by an electro-ejaculation, equilibrated in a Triladyl® (0, 2, 4, 6, and 8 h) containing glycerol and egg yolk and frozen by programmable freezing (PF) or manual freezing (MF). After thawing, sperm samples were subjected to the motility (computer-assisted sperm analysis [CASA]), viability (SYBR-14/PI), and fertilizing ability (FA) (in vitro penetration/fertilization test on bovine oocytes) assays. It was found that the equilibration of 6 h (E-6) ensured higher post-thaw sperm motility and progressive movement compared with other lengths tested, irrespective of a freezing technique. The E-6 sperm viability did not differ between PF and MF but was lower (P < 0.05) than control. Sperm FA (E-6) was similar in PF (60.44%) and MF (62%) but slightly lower than in fresh (72.8%). Our data demonstrate that the use of MF was comparable with PF, which can be applied in the field conditions without need in a piece of cost-expensive equipment, which can greatly benefit the gene bank of animal genetic resources.