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Development of new semen cryopreservation techniques improving sperm survival and ensuring availability of viable spermatozoa for a prolonged time‐period after AI is promising tools to reduce sensitivity of timing of AI and enhance overall fertility. The SpermVital® technology utilizes immobilization of bull spermatozoa in a solid network of alginate gel prior to freezing, which will provide a gradual release of spermatozoa after AI. The objective of this study was to compare post‐thaw sperm quality and in vitro sperm survival over time of Norwegian Red bull semen processed by the SpermVital® (SV) technology, the first commercialized production line of SpermVital® (C) and by conventional procedure applying Biladyl® extender (B). Post‐thaw sperm motility was not significantly different between SV, C and B semen (p > .05). However, sperm viability and acrosome intactness were higher for SV than C and B semen (p < .05). Small differences in DNA quality were observed (p < .05). Sperm viability after storage in uterus ex vivo was higher for SV than for C semen (p < .05). Furthermore, sperm survival in vitro over time at physiological temperature was significantly higher for SV semen than C semen as well as B semen during the incubation period of 48 hr (p < .05). In conclusion, the SpermVital® technology is improved and is more efficient in conserving post‐thaw sperm quality and results in higher sperm viability over time in vitro for SV than for C and B semen.  相似文献   
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为研究硒浸种对春小麦种子活力和幼苗生长特性的影响,分别设置0,0.5,1.0,2.5,3.5,5.0,10.0,50.0 mg/L共8个亚硒酸钠溶液浓度,通过发芽试验,比较研究了不同浓度的亚硒酸钠浸种对春小麦种子萌发和幼苗生长的影响.结果表明:随着亚硒酸钠溶液浓度升高,春小麦种子的发芽率、发芽势、发芽指数、活力指数、幼苗和根长以及干鲜重等指标均呈先升高后下降的趋势;1.0 mg/L的亚硒酸钠溶液对小麦种子萌发和幼苗生长有促进作用;随着亚硒酸钠浓度的升高(≥2.5 mg/L),其各项指标显著下降,并对根和苗的生长表现出抑制作用;因此在实际生产中,掌握合适的硒浸种浓度非常关键.  相似文献   
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享尔 《国际木业》2007,37(3):28-29
近两年,我国木制家具出口可以说是超常规发展。2004年我国出口木制家具为129亿件,到了2005年,达到了1.49亿件,增幅高达16%;至2006年,尽管国际上欧美一些发达国家对我国家具出口“反倾销”和知识产权侵权诉讼接连不断,国内下半年又有国家出口退税率下调等显然不利于家具出口的政策出台,但所有这些内外在因素的合力,似乎都未能构成对我国家具出口大潮本质上的阻扼。  相似文献   
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INTODUCTION: Anaesthesia in lambs undergoing experimental surgery may develop problems associated with age-related immune incompetency: a postoperative complication in a 3 week old Scottish blackface lamb after spinal surgery is presented. CASE HISTORY AND MANAGEMENT: Both lamb and ewe were in good condition. The ewe was vaccinated against Clostridium perfringens and Clostridium tetani 5 weeks pre-partum. There were no apparent problems with the lamb's intake of colostrum. Pre-anaesthetic medication was intramuscular medetomidine (10 μg kg(-1)). Anaesthesia was induced and maintained with sevoflurane in oxygen. Morphine (0.5 mg kg(-1)), meloxicam (0.6 mg kg(-1)) and ketamine (1 mg kg(-1) followed by 10 μg kg(-1) minute(-1)) were administered intravenously (IV) for perioperative analgesia. Atracurium (0.5 mg kg(-1) IV, followed by 0.17 mg kg(-1) injected when the first twitch of the four, train-of four count was palpated) was used to improve muscle relaxation. The lamb's trachea was intubated and the lungs mechanically ventilated to maintain normocapnia. Intrathecal morphine (0.2 mg kg(-1)), IV meloxicam (0.3 mg kg(-1)) and edrophonium (0.5 mg kg(-1)) were administered before recovery. Operative and initial recovery periods were unremarkable. Three hours after surgery the lamb became depressed. Tachycardia (180-250 beats minute(-1)), tachypnoea (30 breaths minute(-1)), poor peripheral perfusion and cold pelvic limb extremities were present mimicking severe pain, and/or hypovolaemic shock. Analgesics - morphine (total dose 1.3 mg kg(-1)) - and IV fluid therapy boluses - crystalloids (300 mL), colloids (120 mL) and fresh whole blood (60 mL) - failed to ameliorate clinical signs and so the lamb was euthanized 10 hours after surgery. Post-mortem findings supported a possible diagnosis of peracute Clostridium perfringens enterotoxaemia. CONCLUSION: Clostridium perfringens enterotoxaemia should be considered when clinical signs of severe pain and/or hypovolaemic shock fail to respond to analgesics and fluid resuscitation in lambs after major surgery.  相似文献   
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Objective To identify the incidence of adverse effects caused by morphine 100–170 µg kg?1 administration during surgery in horses. Design Retrospective case record analysis (1996–2000). Animals Eighty‐four healthy (ASA 1 or 2) horses, mean age 5.5 ± 3.1 (SD) years (2 months to 16 years), mean weight 524 ± 14 kg (100–950). Methods Physiological data and evidence of complications were collected from the anaesthetic records of all animals anaesthetized with romifidine, ketamine, diazepam and halothane and undergoing laryngeal surgery or orchiectomy at the Royal (Dick) School of Veterinary Studies. Cases were divided into those receiving (group M+; n = 18) and those not receiving morphine (M?; n = 29), and the data compared. Values for heart and respiratory rate and mean arterial pressure were compared at 15‐minute intervals between 30 and 120 minutes after induction using anova for repeated measures. The incidence of intraoperative problems was compared using Fisher's exact test. Recovery scores were compared using Student's unpaired t‐test. The records of a further 37 horses undergoing umbilical herniorrhaphy (n = 5), arthroscopy (n = 29) or tarsal arthrodesis (n = 3) were also studied but not analysed statistically due to disparate treatment distribution. Results There were no significant differences between the M+ and M? groups. The incidence of post‐operative complications such as box‐walking and colic were similar in each group. Conclusions Morphine doses of 100–170 µg kg?1 do not increase the risk of problems when used to provide perioperative analgesia in horses anaesthetized with romifidine, ketamine, diazepam and halothane. Clinical relevance Morphine provides an acceptable and relatively inexpensive way to provide perioperative analgesia in horses.  相似文献   
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