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51.
吕春荣  权国波 《中国畜牧兽医》2020,47(11):3611-3617
试验旨在研究白藜芦醇对绵羊冷冻精液质量的改善效果。采用假阴道法采集6只云南半细毛羊精液,用含不同浓度(0、0.1、1、10、20 μmol/L)白藜芦醇的Optidyl稀释液稀释后进行细管分装,低温平衡和液氮气相预冻后,在液氮中保存30 d。解冻后测定精子活力、质膜完整性、磷脂酰丝氨酸(PS)分布、顶体完整性和活性氧等指标。结果表明,解冻后10 μmol/L白藜芦醇组精子总活力、直线运动百分率、精子弯尾率分别为76.14%±0.97%、43.56%±0.91%、43.24%±1.68%,均显著高于其他各组(P<0.05);而20 μmol/L白藜芦醇组精子总活力、直线运动百分率、精子弯尾率分别为21.78%±0.79%、25.23%±1.34%、4.84%±0.68%,均显著低于其他各组(P<0.05)。10 μmol/L白藜芦醇组精子顶体完整性最高,为50.47%±0.91%,显著高于其他各处理组(P<0.05)。PS分布结果表明,10 μmol/L白藜芦醇组正常精子百分率为46.43%±2.95%,显著高于20 μmol/L组(31.14%±3.56%,P<0.05),与其他各组无显著性差异(P>0.05)。20 μmol/L白藜芦醇组PS标记率(39.82%±3.38%)显著高于其他处理组(P<0.05)。活性氧试验结果表明,10 μmol/L白藜芦醇组正常精子(63.57%±0.71%)显著高于其他各组(P<0.05);而20 μmol/L白藜芦醇组正常精子(32.45%±1.42%)显著低于其他各组(P<0.05)。综上,在冷冻稀释液中添加白藜芦醇可以改善绵羊冷冻精液品质,这与白藜芦醇的抗氧化特性有关。但是,白藜芦醇的冷冻保护效果具有明显的浓度依赖性,其最佳作用浓度为10 μmol/L,过高浓度的白藜芦醇反而加重精子的冷冻损伤。此外,对于白藜芦醇对绵羊精子的抗冻保护效果仍然需要体外受精或人工授精验证。  相似文献   
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53.
本研究旨在观察阿勒泰大尾羊尾脂油脂对损伤皮肤是否具有修复作用,并与牛油脂、市售商品做比较。研究选择40 只体重在31 ± 1 g 之间的昆明小鼠,雌雄各半,通过构建小鼠皮肤损伤模型,将小鼠分为4 组(羊尾油组、牛油组、市售商品组和空白组)进行试验观察。小鼠皮肤伤口愈合良好,雌鼠的创面愈合能力强于雄鼠,雌鼠伤口愈合速度:羊尾油组>牛油组>市售商品组>空白对照组。雄鼠伤口愈合速度:羊尾油组>市售商品组>牛油组>空白对照组。皮肤组织病理学结果显示,涂抹羊尾脂、牛油脂、市售商品与空白对照处皮肤相比,创伤修复组织中脂肪细胞、胶原纤维以及其他细胞的数量、排列分布均有差异。羊尾油和牛油均有修复皮肤创伤的作用,且羊尾油修复作用更强,羊尾油可通过促进胶原纤维的生成加速皮肤修复。  相似文献   
54.
为了解陕西省靖边县羊布鲁菌的感染及分布状况,自2010年1月—2012年12月,采集陕西省靖边县羔羊、种羊等55 059只的羊血清样品,通过试管凝集反应对布鲁菌病抗体进行检测,分析羊布鲁菌的分布情况。结果显示,55 059份羊血清样品共检出阳性样品78份,其中羔羊样品阳性71份。种羊养殖场和养殖户因引进布鲁菌隐性种公羊造成2个养殖场出现77只病羊,4个养殖户出现117只病羊。羔羊布鲁菌抗体阳性率呈增高趋势,由2010年的0.04%上升到2012年的0.29%;由于引种造成的布鲁菌感染率较高。  相似文献   
55.
This experiment was conducted to evaluate the effect of alfalfa flavonoids (Medicago sativa) on growth performance and serum indexes of sheep.This experiment was performed with hybrid F1 sheep of Suffolk sheep×Small-tailed Han sheep.Twenty-eight sheep with the body weight of (27.02±3.03) kg were randomly divided into 4 groups with 7 replicates in each group and 1 sheep per replicate.Sheep in different groups were fed diets with 0 (group Ⅰ), 0.1% (group Ⅱ), 0.2%(group Ⅲ) and 0.4% (group Ⅳ) alfalfa flavonoids, respectively.The experiment was cosisted of 7-day-preliminary trial and 41-day-formal trial.The results showed as follows:① Dietary supplementation of alfalfa flavonoids had no significant effects on growth performance of sheep(P>0.05).② Dietary supplementation of alfalfa flavonoids had significant effects on the contents of GLB, ASP, BUN, HDL and P in serum (P<0.05).Serum GLB content at the 1st day in group Ⅲ was significantly lower than that in groupsⅠand Ⅱ(P<0.05), serum ASP contents at the 1st and 21th days in group Ⅳ were significantly lower than those in group Ⅰ(P<0.05), serum BUN content at the 1st day in group Ⅳ was significantly lower than that in group Ⅰ(P<0.05), serum HDL content at the 21th day in group Ⅱ was significantly lower than that in groups Ⅰ and Ⅲ (P<0.05), serum P content in group Ⅳ at the 21th day was significantly lower than that in groups Ⅱ and Ⅲ (P<0.05).In conclusion, dietary supplementation of alfalfa flavonoids might modulate lipid metabolism, improve nitrogen utilization, maintain energy metabolic and balance Ca and P contents, and have the potential function for promoting growth and no adverse effect on liver.The results suggested that the appropriate supplemental level of alfalfa flavonoids for sheep was 0.2%.  相似文献   
56.
In order to explore the effect of different L-lysine levels added in semen dilution on the fresh Dorper sheep quality stored at liquid state,3 health Dorper ram were used to collect semen which were equal-packaged and added to solution containing different levels (0,0.1,0.2,0.3,0.4 and 0.5 g) L-lysine in 120 mL diluent and at 0,6,24,30,48,54,72 and 78 h,the sperm motility,membrane integrity and acrosome integrity were detected.The results showed that the sperm motility in groups added 0,0.1 and 0.2 g L-lysine were higher than other groups,and that in 0.4 and 0.5 g L-lysine groups decreased faster than other groups;The sperm motility in 0.5 g L-lysine group reduced to 0 at 30 h,and it reduced to 0 at 48 h in the group added 0.4 g L-lysine;The effective survival time and survival index in the group added 0.1 g L-lysine was higher than other groups (P< 0.05);The membrane integrity of 0.1 g group was the highest,that had no significant difference with control group from 0 to 54 h (P >0.05),while after 72 h the two groups had significant differences (P< 0.05).The membrane integrity in 0.4 and 0.5 g groups were the worst,and that was significant different with other groups (P< 0.05);The acrosome integrity of 0.1 g group was the highest which had no significant difference with control group (P >0.05),0.4 and 0.5 g groups were the worst,the difference between them was not significant (P >0.05),while was extremely significant difference with other groups except for 0 and 6 h (P< 0.01).The results suggested that dilution added a high concentration of L-lysine could inhibit sperm quality,when the count of L-lysine was more than 0.2 g,sperm quality was significantly decreased,adding 0.1 g L-lysine could improve Dorper sheep fresh sperm quality stored at liquid state.  相似文献   
57.
58.
In this study, an indirect ELISA method was established to detect inhibin hormone (INH) epitope peptide vaccine antibody, it would provide oretical reference for the determination of Fine-wool sheep after active immune body INH epitope peptide vaccine antibody. On the basis of the predecessors, using indirect ELISA method to determinate serum INH epitope peptide antibody levels of sheep, and through control different experimental conditions to look for the best experimental conditions. Through explorating the experimental conditions, finally, the testing experiment conditions were determined, which was blocked solution with skimmed milk powder, INH and GnIH synthetic peptides dilution degrees for 20 000 times, the optimum reaction time was 60 min, the best color action time was 15 min. In this experiment, a kind of method to detection antibody in the body after INH active immune sheep was built, it would provide a reference for future research.  相似文献   
59.
本试验通过比较不同饲养标准杜寒杂交肉用绵羊增重、器官发育、屠宰性能及肉品质的差异,确定适宜的饲养标准。采用单因素试验设计,选取体重为(28.30±0.86)kg的杜寒杂交F1代肉羊600只,随机分为4组,每组3个重复,每个重复50只。4组分别饲喂按照以下饲养标准配制的饲粮:本实验室(中国农业科学院饲料研究所农业部饲料生物技术重点实验室)提出的杜寒杂交肉用绵羊饲养标准、美国NRC(2007)、英国AFRC(1993)以及我国农业行业标准的《肉羊饲养标准》(NY/T 816—2004),分别记为CARS、NRC、AFRC和HB。试验期81 d,每3 d记录1次采食量,每20 d进行1次称重,当CARS组羊只的平均体重达到44 kg时,每组选取10只羊进行屠宰,测定其屠宰性能、组织器官重量和肉品质等指标。结果表明:不同组羊只的实际干物质采食量,NRC组AFRC组CARS组HB组,其中NRC组与CARS和HB组间差异显著(P0.05),其他组间差异均不显著(P0.05);平均日增重和胴体重,CARS、HB、AFRC组间差异均不显著(P0.05),且均显著高于NRC组(P0.05);饲料转化率各组间存在显著差异(P0.05),CARS组HB组AFRC组NRC组;屠宰率,CARS组显著高于NRC组(P0.05),与HB、AFRC组间差异均不显著(P0.05);CARS组羊只的心脏、肝脏、肾脏重量占宰前活重比例显著高于其他组(P0.05);背最长肌失水率、肌肉色亮度、红度和黄度值,各组间均无显著性差异(P0.05)。结果提示,杜寒杂交肉羊在不同饲养标准下的实际日增重200~220g,从增重和屠宰性能上来看,CARS制订的饲养标准与国外饲养标准相比具有明显优势。  相似文献   
60.
5 male Small-tail Han sheep with the body weight of 45 kg at 1.5 years old,fitted with permanent rumen fistula,to study of the effect of the supplement of the untreated commercial lysine on the rumen microbiocoenosis,rumen metabolism and whole body metabolism by 5×5 Latin square design (5 groups:control,control with low urea (equal nitrogen),low lysine,control with high urea (equal nitrogen),high lysine).The amounts of lysine-HCl supplement were 0,4.0 and 8.0 g/kg diet (as DM basis) in each group respectively,with two urea supplement control groups of equal amount of nitrogen.The results showed that by supplement of 4.0 and 8.0 g/kg of lysine-HCl diet (as DM basis) respectively,the voluntary intake of dry matter of sheep were increased by 5.5%(P>0.05) and 11.8%(P<0.05) respectively.The total amount of rumen bacteria were increased by 18.9%(P<0.01) and 23.9%(P<0.01) respectively,as the amount of rumen Coccus was increased by 21.2%(P<0.01) and 30.1%(P<0.01) respectively.The amount of rumen big Bacillus was decreased by 16.7%(P<0.05) and 33.3%(P<0.01) respectively.The total VFA of was increased by 9.6%(P<0.05) and 12.2%(P<0.01) respectively,as the butyric acid was increased by 12.8%(P>0.05) and 20.2%(P<0.01) respectively.The apparent digestibility of organic matter was increased by 6.4%(P>0.05) and 10.0%(P<0.05) respectively,the apparent digestibility of crude protein was increased by 7.0%(P>0.05) and 18.3%(P<0.01) respectively;And nitrogen retention was increased by 46.4%(P>0.05) and 110.7%(P<0.01) respectively.However,there was no effect of lysine supplement on the amounts of the rumen protozoa and fungi,and the concentration of rumen ammonia nitrogen.It was concluded that the supplement of untreated commercial lysine to adult sheep would increase the voluntary intake,digestibility,nitrogen retention the rumen microbiocoenosis and the total amount of rumen bacteria,especially the rumen Coccus of adult sheep.The effect of lysine supplement could not be replaced by urea supplement completely.  相似文献   
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