Adjusted method of penis fixation during boar semi-automatic semen collection aiming to reduce bacterial contamination

Semen collection has an essential role in the initial bacterial load in boar ejaculates and extended semen. The study aimed to explore the efficacy of an adjusted penis fixation in a semi-automatic collection system on reducing bacterial contamination of ejaculates in two-boar studs with different scenarios. Historically, stud A had low levels of bacterial load in raw semen, while stud B had a high level of contamination. A total of 56 mature boars had their semen collected using two methods of penis fixation: (a) Traditional: The penis was fixed directly with the artificial cervix and transferred to the adjustable clamp; (b) Adjusted: The fixation was performed with one gloved-hand, and after exteriorization, the penis was gripped using the artificial cervix with the other gloved-hand and transferred to the adjustable clamp. The bacterial load (p = .0045) and the occurrence of ejaculates >231 CFU/ml (p = .0101) were reduced in the Adjusted compared to the Traditional method. Bacterial load was reduced when using the Adjusted method in stud B (p = .0011), which showed a greater occurrence of critical factors for bacterial contamination (p ≤ .0034). The Adjusted method reduced the occurrence of ejaculates >231 CFU/ml when the preputial ostium was dirty (p = .016) and the duration of semen collection was >7 min (p = .022) compared to the Traditional method. In conclusion, the Adjusted penis fixation was efficient in reducing bacterial load of ejaculates, mainly in boar stud B, which had high contamination challenges.     

猪精液常温保存效果的研究

主要从稀释液配方、抗生素种类、稀释比例等方面研究了猪精液常温保存的效果。结果表明,在6种稀释液中,添加了抗生素的进口BTS和自配的Modena液效果较好,含800-1000IU／mL青霉素、链霉素稀释液的保存效果优于含800-1000IU／mL青霉素、链霉素＋0．24mg/mL庆大霉素稀释液的保存效果,1：1-1：4的稀释比例适合于猪人工授精。     

不同稀释液对猪精液常温保存效果的研究

主要从稀释液的组分、抗生素的种类以及抗氧化剂的添加来研究猪精液常温保存的稀释液配方。结果表明：含有一定量的牛血清白蛋白有利于猪精液的保存。通过恩诺沙星、氧氟沙星、庆大霉素、菌特灵与青、链霉素对精液保存效果的比较，得出添加50μg/mol恩诺沙星的保存效果优于其它药剂。不同浓度的褪黑激素对精液保存有一定的影响，10^-5mol/L的褪黑激素可延长精子的存活时间。     

EGTA对猪精液液态保存的影响

猪精液液态保存体系中,钙离子浓度升高将降低精子活力,缩短精子体外保存时间。常用的金属螯合剂EDTA的溶解度较低,且容易发生沉淀,因此改进螯合剂对于改进猪精液保存液配方,提高猪精液液态保存质量十分重要。本研究中我们在精液液态保存液中分别添加不同浓度(1.5,3,6,12 mmol/L)的钙离子螯合剂EGTA,检测其对猪精子的活力、质膜完整性、顶体完整率、获能情况以及受精能力的影响。结果表明,精液保存液中添加EGTA能显著提高猪精子保存质量,其中添加3 mmol/L EGTA效果最好(P<0.05)。与对照组相比,添加3 mmol/L EGTA时,体外受精率和囊胚率显著提高(P<0.05)。因此,精液保存液中添加EGTA有助于提高猪精液液态保存的质量。     

黄芪多糖对猪精液低温保存的影响

通过在改进的猪精液低温稀释液中添加不同质量浓度的黄芪多糖(0、0.10、0.20、0.30、0.40g/L),对比7d内、4℃低温保存下猪精子的活率、活力、精子畸形率、精子质膜和顶体的完整性等参数,探讨黄芪多糖在猪精液低温保存应用的效果。结果显示,在猪精液低温保存后的质量上,0.10g/L质量浓度组与对照组差异不显著(P0.05),0.40g/L质量浓度组显著差于对照组(P0.05),0.20、0.30g/L质量浓度组显著好于对照组(P0.05),所有各组中0.30g/L质量浓度组效果最好。结果表明,在本试验条件下,适宜质量浓度的黄芪多糖可以明显改善4℃低温条件下猪精液的保存效果,其中最佳添加质量浓度是0.30g/L。     

两种抗菌药对猪精液常温保存效果的影响

通过添加不同浓度的恩诺沙星和庆大霉素对猪精液进行常温保存试验,对猪精子的有效存活时间、总存活时间及生存指数进行评价.结果表明,含400 IU/mL恩诺沙星和480 IU/mL庆大霉素的精液常温保存效果较好.     

The effect of photoperiod on selected parameters of boar semen

The objective of the present research was to determine the effect of increasing and decreasing natural photoperiods on selected parameters of boar ejaculates. The study material consisted of 17 boars: six Polish Large White (PLW) breed, five Polish Landrace (PL) breed, and six Duroc×Pietrain (D×P) crossbreed, all aged between 8 and 12 months at the beginning of the research. Analyses were conducted on 612 ejaculates, which were collected in two experimental periods: an increasing photoperiod (IP) (January–June) and a decreasing photoperiod (DP) (July–December). A statistically proven impact of photoperiod on the volume of semen was observed in all the studied breeds (P=0.004). During the decreasing photoperiod the mean volume of semen was 261.16±75.20 ml and this was almost 17 ml higher than that for the increasing period. For boars involved in the experiment, day length also had a significant impact on the total number of motile spermatozoa (P=0.037). In the increasing photoperiod the mean number was 3.26×10⁹ lower. A decreasing photoperiod has a positive affect on both boars and the parameters of the collected ejaculates, which were observed in the higher number of insemination doses per ejaculate. Between the different breeds, the reactions of boars to photoperiod differed and the most significant influence of photoperiod on semen parameters was noted among D×P breed boars. Least susceptible to changes in day length were PLW breed boars.     

浅析猪精液常温保存技术的研究现状

为了更好地将常温保存的猪精液最大限度地利用,提高猪人工授精的效率。文章结合团队近些年的研究成果,介绍了猪精液常温保存的原理,影响猪精液保存的物理因素、微生物因素,精液稀释方法以及精液稀释液成分等,对提高猪精液常温保存的质量和延长保存时间提供技术支持,为将来猪精液低温保存,乃至冷冻精液保存技术的发展和完善提供参考和帮助。     

抗生素对猪精液常温保存效果的影响

采集9头公猪的精液（其中长白4头、大白4头、杜洛克1头）,对精液进行稀释后,分别加入9种抗生素,在18℃保存,测定精子保存时间和精子存活指数.结果表明：磺胺抗菌效果最好,其有效保存时间为4.38 d,精子存活指数为3.14.恩诺沙星、阿奇霉素、林肯霉素的抗菌效果次之,庆大霉素、青链霉素的抗菌效果再次之,新霉素、卡那霉素的抗菌效果最差.     

Supplemental effect of different levels of taurine in Modena on boar semen quality during liquid preservation at 17°C

Peroxidation damage induces sublethal injury to boar sperm during the storage process. Taurine has already been demonstrated to protect cells effectively from oxidant‐induced injury. This study was aimed to evaluate the effect of different concentrations of taurine (0.5, 1, 5 and 10 mmol/L) in Modena diluent on boar sperm quality during liquid storage at 17°C. Ejaculates from sexually mature Duroc pigs were collected, pooled and preserved in the Modena containing different concentrations of taurine. Sperm motility, plasma membrane integrity, acrosome integrity, total antioxidative capacity (T‐AOC) activity and malondialdehyde content (MDA) were examined every 24 h. Modena diluent containing taurine suppressed the reduction in sperm qualities during the process of liquid preservation compared with those of the control group. After 5 days of liquid preservation, the addition of taurine at 5 mmol/L had the optimal effect on survival time as well as maintenance of motility, plasma membrane integrity, acrosomal integrity, T‐AOC activity and MDA content. These results may suggest the possibility that the proper addition of taurine to the semen extender improves the swine production system using artificial insemination by the suppressing of sperm damage and subsequent dysfunction during liquid preservation.     

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.     

Qualitative changes and the fertilizing capacity of sperm after 6 years of preservation of boar semen

Sperm motility, acrosome morphology, changes determined by the vital-lethal test and aspartate aminotransferase (AST) concentration in semen plasma were evaluated in the semen of four boars; the semen was stored for six years. No statistically significant changes in the percentage of motile spermatozoa were indicated when sperm motility was evaluated after four and six years of semen storage in liquid nitrogen. Neither did the fluctuation of the changes found on the basis of the vital-lethal test go beyond statistically insignificant values. After semen sample thawing in the BTS medium, the motility of spermatozoa was found to be somewhat higher than after thawing in the INRA-ITP medium, but after the termination of the thermoresistance test both media appeared to be equally effective. The AST level of the semen samples stored for four years was just slightly up on the initial values. After thawing in the BTS medium, AST level increased by 0.03 microcatal per litre of semen plasma, and in the INTRA-ITP medium by 0.06 microcatal per litre of semen plasma. The insemination of five sows with the semen stored for six years results in conception of two sows, i. e. 40%, and the average litter size was 7.5 piglets. It can be derived from the results that six years of boar semen storage in liquid nitrogen cause no further substantial changes in the structural and functional characteristics of spermatozoa.     

The effects of different levels of superoxide dismutase in Modena on boar semen quality during liquid preservation at 17°C

This study was conducted to investigate the influence of superoxide dismutase (SOD) on the quality of boar semen during liquid preservation at 17°C. Semen samples from 10 Duroc boars were collected and pooled, divided into five equal parts and diluted with Modena containing different concentrations (0, 100, 200, 300 and 400 U/mL) of SOD. During the process of liquid preservation at 17°C, sperm motility, acrosome integrity, membrane integrity, total antioxidant capacity (T‐AOC) activity, malondialdehyde (MDA) content and hydrogen peroxide (H₂O₂) content were measured and analyzed every 24 h. Meanwhile, effective survival time of boar semen during preservation was evaluated and analyzed. The results indicated that different concentrations of SOD in Modena showed different protective effects on boar sperm quality. Modena supplemented with SOD decreased the effects on reactive oxygen species on boar sperm quality during liquid preservation compared with that of the control group. The added 200 U/mL SOD group showed higher sperm motility, membrane integrity, acrosome integrity, effective survival time and T‐AOC activity. Meanwhile, the added 200 U/mL SOD group showed lower MDA content and H₂O₂content. In conclusion, addition of SOD to Modena improved the boar sperm quality by reducing oxidative stress during liquid preservation at 17°C and the optimum concentration was 200 U/mL.     

The effect of Curcuma longa extracted (curcumin) on the quality of cryopreserved boar semen

The aim of this study was to determine the optimal concentration of curcumin needed for cryopreservation of boar semen. Semen samples (n = 9) were collected from nine Duroc boars which having proven fertility were used for routine artificial insemination. Semen samples were collected and divided into six groups (groups A‐F) according to various concentrations of curcumin in freezing extender (i.e. 0, 0.125, 0.25, 0.50, 0.75 and 1.0 mmol/L, respectively). The semen was frozen by traditional liquid nitrogen vapor method and stored at ?196°C in the liquid nitrogen tank. After storage, frozen semen samples were thawed at 50°C for 12 s and evaluated for progressive motility, viability and acrosome integrity. The present results indicated that the addition of curcumin at 0.25 (group C) or 0.50 mmol/L curcumin (group D) yielded the higher percentage of progressive motility (33.3 and 36.1%, respectively) (P < 0.001). A significantly higher percentage of acrosome integrity was found in groups B (29.7%), C (31.1%) and D (30.2%) than in the other groups (P < 0.01). However, there was no significant difference in percentage of viability among groups. In conclusion, addition to the freezing extender of curcumin during cryopreservation at a concentration of 0.25 or 0.50 mmol/L is the optimal concentration of curcumin for improving the quality (i.e. increased progressive motility and acrosome integrity) of cryopreserved boar semen.     

Influence of boar and semen parameters on motility and acrosome integrity in liquid boar semen stored for five days

Ninety ejaculates from a total of 76 AI boars were extended in Beltsville Thawing Solution (BTS). Boar identity, breed, weight of the ejaculate and sperm concentration were registered. Motility and acrosome integrity were assessed after storage at 16-18 degrees C for 6, 30, 54, 78, and 102 h. Storage time had a significant influence on both motility (p < 0.01) and acrosome integrity (p < 0.001). The Least Square Means for percentage of motility showed a small decline from 79.8% after 6 h of storage to 78.4% at 102 h. Motility at 78 and 102 h was significantly different from motility at 6 h (p < 0.05). The percentage of sperm cells with normal acrosomes declined throughout the experiment. The Least Square Means for 6, 30, 54, 78, and 102 h of storage were 93.9%, 90.6%, 88.0%, 84.8%, and 78.2%, respectively. The decrease in acrosome integrity from one storage time to the next was highly significant throughout the trial (p < 0.001). There was a significant influence of boar (p < 0.001) and sperm concentration (p < 0.01) on motility, while acrosome integrity was affected only by boar (p < 0.001). Breed of the boars and weight of the ejaculate did not influence the dependent variables.     

褪黑素、谷胱甘肽对猪精液冷冻保存效果的影响

本试验旨在研究褪黑素、谷胱甘肽两种抗氧化剂对精子冷冻的保护效应。以成年杜洛克公猪为研究对象,在猪精液冷冻稀释液中先后单独、联合添加褪黑素、谷胱甘肽,解冻后精子质量通过检测活率、活力、顶体完整性、线粒体活性以及活性氧（ROS）含量来判定。结果表明：分别单独添加0.25mg/mL褪黑素、5mmol/L谷胱甘肽,或联合添加0.125mg/mL褪黑素和1mmol/L谷胱甘肽,均能减少精液冷冻过程中ROS的生成,显著提高冷冻精子解冻后的质量（P〈0.05）,其中联合添加效果显著优于单独添加效果。     

安普霉素对雏鸡生产性能的影响

选用60只1日龄健康罗曼褐雏鸡,随机分成3组,Ⅰ组饮水给药5mg/kg安普霉素,Ⅱ组饮水给药10mg/kg安普霉素,Ⅲ组凉白开水对照,检测雏鸡的生产性能。结果说明持续添加安普霉素可使雏鸡的日增重和料重比大大提高,其中低剂量安普霉素对雏鸡日增重和饲料报酬的改善显著高于对照组(p<0.05)。     

水蛭素对猪精液冻后质量的影响

试验用含不同浓度(0、0.02%、0.04%、0.06%、0.08%、0.10%、0.12%)水蛭素的稀释液稀释美系公猪精液,并以0.25mL细管分装冷冻。结果显示:(1)水蛭素浓度为0、0.02%时在冻后精子畸形率或水蛭素浓度为0、0.12%时冻后精子顶体完整率上存在明显的品种效应(P0.05);(2)3种公猪各浓度组(除大约克和杜洛克公猪0.02%浓度组外)冻后精子活力均显著高于对照组(P0.05),且均在浓度为0.08%时最高;除了长白公猪0.02%浓度组冻后精子畸形率显著低于对照组(P0.05)外,3种公猪各浓度组与对照组差异均不显著(P0.05);大约克公猪各试验组、杜洛克公猪0.08%浓度组及长白公猪0.02%、0.06%及0.08%浓度组冻后精子顶体完整率显著高于对照组(P0.05),且均在浓度为0.08%时最高,长白及杜洛克公猪其他试验组与对照组差异均不显著(P0.05)。结果表明,适宜浓度的水蛭素可以显著提高猪精液冻后质量,效果最好的浓度为0.08%。