低温保护剂对4℃保存猪精液活率的影响

本实验采用1%浓度的甘油、乙二醇、二甲基乙酰胺、二甲亚砜作为精液低温保护剂,通过精子降温-冷藏-复苏三个重要步骤,观察第7d保护剂对精子活率的影响。结果表明:在4℃下,乙二醇对精子活率保护作用最好,第7d仍能达到0.6以上;其次是甘油、二甲基乙酰胺和二甲亚砜组;空白对照组活率最低,低于0.2。     

中药“双黄连”涂膜剂的试制及其在兽医临床上的应用

涂膜剂是用高分子化合物(如聚乙烯醇缩甲乙醛)的有机溶媒溶解药物而制成的外用液体涂剂,用时涂于患处,溶媒挥发后形成薄膜,对患处有保护作用,同时能逐渐释放药物而起治疗作用。涂膜剂是近来我国制剂工业中在硬膏剂、火棉胶剂应用的基础上发展起来的一种中西药结合的新剂型。其薄膜材料是聚乙烯醇缩甲乙醛,增塑剂为邻苯二甲酸二丁脂,乙醇、丙酮为溶媒。一年来,我们经过多次试验,成功制成以聚乙烯醇为成膜材料,以甘油为增塑     

不同冷冻剂对鹅精液品质及受精率的影响

本试验在鹅精液稀释液筛选的基础上,利用籽鹅、豁鹅和莱茵鹅的精液对冷冻保存剂进行筛选,并测定了颗粒冻精解冻后的精子活力、畸形率、死亡率及受精率。在所选择的冷冻剂二甲基乙酰胺(dimethylacetamide,DMA)、甘油、二甲基亚砜(dimethyl sulfoxide,DMSO)和乙烯二醇(ethylene glycol,EG)中,以DMA作为冷冻剂的各项指标效果最佳。     

复方氟苯尼考长效注射液制备工艺及稳定性和安全性研究

氟苯尼考是动物专用的广谱抗生素,其应用剂型目前主要有注射剂、预混剂和溶液剂,国内外均为单方制剂。以氟苯尼考配伍甲氧苄啶,利用非水混合溶剂,研究了复方氟苯尼考注射液的制备;通过温度加速试验、光加速试验及长期稳定试验,考察了该复方制剂的稳定性;通过肌内和血管注射刺激性试验,考察了该复方制剂的应用安全性。结果显示:处方用量为60%的二甲基乙酰胺与40%的α-吡咯烷酮是最佳混合溶剂条件。稳定性试验观察外观性状均为淡黄色,澄明度均澄清,主要成分含量稳定。试验表明:该复方制剂处方设计合理,制备工艺易于控制,质量稳定可靠,注射应用安全,为强化氟苯尼考的临床应用效果,提供了可行的产品选择。     

30%土霉素注射液制备工艺的研究

为开发出优质的30%的土霉素注射液,通过在比较不同溶媒下制剂的性状,筛选最佳溶媒,利用正交试验确定注射液的最佳组方,同时对制剂的添加工艺进行探索。最终得出制备30%土霉素注射液最佳配方为:六水合氯化镁11%,甲醛合次硫酸氢钠0.8%,注射用水5%,二甲基甲酰胺60%,聚乙烯吡咯烷酮K17 5%。添加工艺为六水合氯化镁和甲醛合次硫酸氢钠溶解于注射用水中,体系中加入有机溶媒,并依次溶解聚乙烯吡咯烷酮K17和盐酸土霉素,最后调pH,灭菌灌装。结果表明,在本试验条件下所得30%土霉素注射液,符合国家兽药标准,性状稳定,价格经济,工艺简单,适合工业化生产。     

用吉灭素(Димецин)治疗线虫病的疗效试验

全苏兽药制剂科学检查院,合成研究的兽药制剂吉灭素,本品是动物线虫病的有效驱虫剂。吉灭素系橙红色晶末,无吸湿性,溶于一般的有机溶媒中,保存时稳定,在74—75℃的温度条件下溶化。易溶于水,在含有醋酸、盐酸、磷酸的环境下则形成盐。吉灭素对试验动物和农畜进行了毒性研究。将其混于淀粉混悬液中一次内服。18—20克重小白鼠对吉     

土霉素混悬剂的研制及药物质量指标测定

为了研制优质的土霉素混悬剂,试验采用单因素试验及正交试验法,筛选了土霉素混悬剂的理想配方,以土霉素为主药, 以蒸馏水为溶媒,应用分散法成功研制了土霉素混悬型制剂,并评定了混悬剂的质量指标.试验结果表明,测定的4种不同浓度混悬剂样品的平均回收率为100.62%,RSD为0.48%,静置3h的沉降体积比均大于0.9,且混悬剂稳定性好,不易结块,易于重分散.     

各类家禽精液冷冻保存方法试验

（１）试验用二甲基乙酰胺（ｄｉｍｅｔｈｙ－ｌａｃｅｔａｍｉｄｅ）冷冻（－１９６℃）保存的鸡、火鸡、鹅、鸭精液的受精率。（２）输精试验结果，冷冻—解冻精液受精率分别为：鸭６９％～９０％，鹅８１％～９０％，火鸡８０％～９０％，鸡７５％～８５％。     

二甲基乙酰氨在鸡精液冷冻中的作用分析

用二甲基乙酰氨（ＤＭＡ）及甘油作为冷冻保护剂，对鸡精液进行冷冻保存，解冻后观察精子活力，并进行输精试验，发现以ＤＭＡ作为冷冻保护剂冷冻的精子解冻后活力及人工输精后的受精率都显著高于以甘油作冷冻保护剂的结果。经过毒性试验、冷冻试验及输精试验，发现ＤＭＡ的确是一种效果较好的冷冻保护剂。它在许多方面比甘油更为理想。本文还叙述了ＤＭＡ的性质及作用机理     

各类家禽精液冷冻保存方法试验

（１）试验用二甲基乙酰胺）ｄｉｍｅｔｈｙ－ｌａｃｅｔａｍｉｄｅ）冷冻（－１９６℃）保存的鸡、火鸡、鹅、鸭精液的受精率。（２）输精试验结果，冷冻一解冻精液受精率分析为：鸭６９％－９０％，鹅８１％－９０％，火鸡８０％－９０％，鸡７５％－８５％。     

Evaluation of intratesticular injection of glycerol for nonsurgical sterilization of dogs

OBJECTIVE: To determine efficacy of intratesticular injection of glycerol as a means to sterilize dogs. ANIMALS: Six 2- to 4-year-old sexually intact male dogs. PROCEDURE: Testicular volume, serum testosterone concentration, and number of sperm in ejaculate were determined before and at weekly intervals for 12 weeks following intratesticular injection of a 70% glycerol solution (1 ml/testis). Testicular tissue specimens for histologic evaluation were obtained 4, 8, and 12 weeks following injection. RESULTS: Number of sperm in ejaculate following glycerol injection was not significantly different from number before injection. Compared with preinjection values, serum testosterone concentrations were significantly less 5, 9, and 10 weeks following injection, although libido and ejaculate characteristics were unchanged. Testicular swelling was evident 24 to 48 hours following injection, and testicular volume decreased starting on week 5 following treatment. Seminiferous tubules and evidence of normal spermatogenesis were detected in testicular biopsy specimens obtained from all dogs 12 weeks following injection. CONCLUSION AND CLINICAL RELEVANCE: Intratesticular injection of a 70% glycerol solution did not result in azoospermia and sterility in dogs.     

影响精液冷冻和人工授精效果的因素

通过对精液冷冻保存的细胞反应原理的阐述 ,指出冷冻保护剂甘油对精液保存具有利弊效应 ,提出精子膜脂组成的差异使得不同品种的精子对冷冻损伤的易感性不同。雌性生殖道解剖结构的品种差异 ,精子形态 ,精子运行机制的细微差异 ,人工授精时间及精子的运行能力 ,采精方式等因素对精液冷冻保存和人工授精的成功有决定性作用。研究精子质膜的生物学特性可解决低活力精子的问题 ,然而这并不能解决冷冻后精子质量的个体差异。对精细胞基因组的研究可以找出这些个体的遗传差异。因此 ,冷冻精子和精原细胞 (用于细胞外注射 )的差异已经成为完整基因组问题。     

Preservation of fowl semen in liquid nitrogen--an improved method

1. An improved method of storing fowl semen in liquid nitrogen is described. It uses glycerol as a cryopotectant and the degree of fertility obtained with semen stored for up to 2 1/4 years was very promising. 2. The essential features of the method are a slow freezing rate, a reduction of temperature to - 35 degrees C before the semen is plunged into liquid nitrogen and insemination within 15 min of thawing and removing the glycerol from the diluent. 3. It seems likely that further improvements in the technique may be expected through better control of the injection of liquid nitrogen into the freezing chamber, thereby minimising localised, rapid temperature changes around the ampoules during freezing. 4. Preliminary results suggest that it may prove possible to select males for the ability of their spermatozoa to withstand freezing. 5. The importance of recognising differences between males in the initial quality of semen and between females in the physiology of the reproductive organs in determining the fertilising ability of stored semen is discussed.     

Neurotoxic effects of ivermectin administration in genetically engineered mice with targeted insertion of the mutated canine ABCB1 gene

Objective-To develop in genetically engineered mice an alternative screening method for evaluation of P-glycoprotein substrate toxicosis in ivermectin-sensitive Collies. Animals-14 wild-type C57BL/6J mice (controls) and 21 genetically engineered mice in which the abcb1a and abcb1b genes were disrupted and the mutated canine ABCB1 gene was inserted. Procedures-Mice were allocated to receive 10 mg of ivermectin/kg via SC injection (n = 30) or a vehicle-only formulation of propylene glycol and glycerol formal (5). Each was observed for clinical signs of toxic effects from 0 to 7 hours following drug administration. Results-After ivermectin administration, considerable differences were observed in drug sensitivity between the 2 types of mice. The genetically engineered mice with the mutated canine ABCB1 gene had signs of severe sensitivity to ivermectin, characterized by progressive lethargy, ataxia, and tremors, whereas the wild-type control mice developed no remarkable effects related to the ivermectin. Conclusions and Clinical Relevance-The ivermectin sensitivity modeled in the transgenic mice closely resembled the lethargy, stupor, disorientation, and loss of coordination observed in ivermectin-sensitive Collies with the ABCB1-1Δ mutation. As such, the model has the potential to facilitate toxicity assessments of certain drugs for dogs that are P-glycoprotein substrates, and it may serve to reduce the use of dogs in avermectin derivative safety studies that are part of the new animal drug approval process.     

乙酰丙酮分光光度法测定甘油缩甲醛中游离甲醛含量

乙酰丙酮与甲醛在乙酸-乙酸铵介质中形成黄色化合物,该化合物在411 nm波长处有最大吸收。甲醛在比色液中含量小于4μg/mL时,符合比尔定律,线性相关系数R2=0.999 9。对样品平行6次测定相对标准偏差为0.68%~1.62%,回收率为91.2%~93.8%。该方法测定甘油缩甲醛中游离甲醛含量简便、快捷,准确可靠。     

Improving the quality of rooster semen frozen in straws by screening the glycerol concentration and freezing rate

ABSTRACT

• 1. This study examined different glycerol concentrations (GC) and freezing rates to improve the quality of rooster spermatozoa frozen in straws, and to determine the effect of varying GC on post-thawed spermatozoa quality, as evaluated by fertility and hatchability.

• 2.The experiment included two tests. In test 1, rooster semen straws containing 2, 4, 6, 8 and 11% glycerol were put in a rack (nine tiers with a 1 cm interval between every two tiers, 1 to 9 cm above liquid nitrogen (LN) source), and gradually frozen. The semen straws located in different tiers experienced different temperatures and freezing rates. The straws were then thawed and live sperm numbers determined. In test 2, rooster semen straws containing 2, 4, 6, 8 and 11% glycerol were put on optimal tiers (identified in test 1) for freezing, and stored at ?196°C. Hens were inseminated with the frozen semen (post-thawed and glycerol removed, about 4.0 × 10⁸ sperm per hen), and eggs incubated.

• 3. The numbers of live sperm in the 11% glycerol group was higher than that in 2, 4 or 6% glycerol group (P < 0.05) for the semen straws on tiers 1 to 9, while that on tiers 1 to 5 was lower than that on tier 6 to 8 (P < 0.05). GC, freezing rate and the interaction between GC and freezing rate had a significant effect on live sperm numbers (P < 0.01). The highest fertility was in the 6% glycerol group and occurred on day 5 after insemination. The lowest fertility occurred in the 2% glycerol group on day 10 after insemination.

• 4. The optimal combination was 11% glycerol in straws located 6 cm above the LN surface (on tier 6). The 6% glycerol group achieved the highest fertility (77.6%), which surpassed that reported in recent years.

     

Effects of Rapid Cooling Prior to Freezing on the Quality of Canine Cryopreserved Spermatozoa

The aim of this study was to evaluate the effects of rapid cooling prior to freezing on frozen-thawed canine sperm quality. In experiment 1, centrifuged ejaculates from 6 dogs were pooled, split into 4 aliquots and cryopreserved by the Uppsala procedure using different cooling rates (control, cooling speed 18 C/90 min and average cooling rate 0.2 C/min; rapid, cooling speed 18 C/8 min and average cooling rate 2.25 C/min) in combination with 2 glycerol addition protocols (fractionated or unfractionated). In experiment 2, centrifuged ejaculates from 4 dogs were processed individually using the same cooling rates described in experiment 1 in combination with an unfractionated glycerol addition protocol. Each of the experiments was replicated 5 times. Sperm quality was evaluated after 30 and 150 min of post-thawing incubation at 38 C. Total motility (TM), progressive motility (PM) and quality of movement parameters were assessed using a computerized system, and sperm viability (spermatozoa with intact plasma and acrosome membranes) was assessed using flow cytometry (H-42/PI/FITC-PNA). Values for TM, PM, viable spermatozoa and the quality of movement parameters after thawing were not significantly affected by the cooling rate. The interaction between the cooling rate and the added glycerol protocol was not significant. There were significant differences among the males (P<0.01) in the sperm quality parameters evaluated after thawing. The interaction between the males and the cooling rate was not significant. In conclusion, canine spermatozoa can be cryopreserved using the Uppsala method at an average cooling rate of 2.25 C/min prior to freezing together with addition of fractionated or unfractionated glycerol.     

Effects of transforming growth factor‐β1 treatment on muscle regeneration and adipogenesis in glycerol‐injured muscle

Transforming growth factor (TGF)‐β1 is associated with fibrosis in many organs. Recent studies demonstrated that delivery of TGF‐β1 into chemically injured muscle enhances fibrosis. In this study, we investigated the effects of exogenous TGF‐β1 on muscle regeneration and adipogenesis in glycerol‐injured muscle of normal mice. Tibialis anterior (TA) muscles were injured by glycerol injection. TGF‐β1 was either co‐injected with glycerol, as an ‘early treatment’ group, or injected at day 4 after glycerol, as a ‘late treatment’ group and the TA muscles were collected at day 7 after initial injury. Myotube density was significantly lower in the early treatment group than in the glycerol‐injured group (without TGF‐β1 treatment). Moreover, the Oil red O‐positive area was significantly smaller in the early treatment group than in the late treatment group and glycerol‐injured group. Furthermore, TGF‐β1 treatment increased endomysial fibrosis and induced immunostaining of α‐smooth muscle actin. The greater inhibitory effects of early TGF‐β1 treatment than that of late TGF‐β1 treatment during regeneration in glycerol‐injured muscle suggest a more potent effect of TGF‐β1 on the initial stage of muscle regeneration and adipogenesis. Combination of TGF‐β1 with glycerol might be an alternative to enhance muscle fibrosis for future studies.     

The role of maternal triglycerides in the supply of lipids to the ovine fetus.

Maternal and fetal blood samples were obtained for up to 20 min after the injection of an emulsion of 14C-labelled glycerol tripalmitate into the circulation of pregnant ewes. No evidence was obtained for the direct transfer of intact triglycerides across the placenta. Results obtained suggest that there was a very rapid uptake of the triglyceride from the maternal circulation followed by hydrolysis and release of free fatty acids back into the maternal circulation.     

谷氨酰胺替代部分甘油对冻融猪精子获能和体外受精能力的影响

本试验旨在探索用谷氨酰胺（Gln）替代部分甘油对冻融猪精子体外获能和受精能力的影响，试验分为6组：3%甘油对照组和5个处理组（Ⅰ~Ⅴ组：2%甘油＋谷氨酰胺（0、20、40、80和100 mmol/L））。对冻融松辽黑猪精子的精子活力、质膜完整性、顶体完整性、线粒体膜电位、鱼精蛋白水平、获能及体外受精等指标进行了检测。结果显示，用谷氨酰胺替代部分甘油均对冻融精子质量有一定的改善作用，改善的程度受谷氨酰胺浓度的影响。与对照组相比，Ⅰ组精子的质量参数均显著下降（P<0.05）；与Ⅰ组相比，Ⅱ组精子活力、顶体完整性和活率显著提高（P<0.05），Ⅲ组精子线粒体膜电位显著提高（P<0.05），Ⅴ组精子活力、质膜完整性、顶体完整性、活率和线粒体膜电位均显著提高（P<0.05）。说明用谷氨酰胺替代部分甘油对精子质量具有很大的影响，且当谷氨酰胺为100 mmol/L时可得到更高质量的精子，因此，后续试验使用浓度为100 mmol/L的谷氨酰胺进行研究。与对照组相比，2%甘油＋100 mmol/L谷氨酰胺处理组精子鱼精蛋白缺失率显著下降（P<0.05），精子获能无显著差异（P>0.05），但胚胎卵裂率显著提高（P<0.05）。综上所述，谷氨酰胺可作为一种新型冷冻保护剂替代部分甘油来提高猪精液的质量，并降低甘油对猪精液的毒性作用，为猪精液的冷冻保存及商业化生产提供技术支撑。