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61.
Objective To evaluate the pre‐emptive analgesic effect of pre‐incisional epidural ketamine. Study Design A blinded, randomized experimental study. Animals Sixteen mixed breed mares, 7.6 ± 2.8 years old, weighing 352 ± 32 kg. Methods In a pilot study, an incision was made on one lateral thigh using a lidocaine block and no further analgesics, and it was verified that the nociceptive threshold was lower on the incised side than nonincised side (p ≤ 0.05), and that von Frey filaments evoked a pain response. The 16 animals were divided into group A (ketamine, n = 9) and B (saline, n = 7). An epidural catheter was inserted 24 hours before the trials. The thigh was shaved bilaterally, and the right side was blocked (incised side) using lidocaine. Twenty‐five minutes later, ketamine (A) or saline (B) was administered epidurally. Five minutes later, a 10‐cm skin incision was made on the right side, and then sutured. Nociceptive threshold was determined with von Frey filaments at 1, 3, and 5 cm around the incision at 15‐minute intervals for 2 hours, then at 4, 6, and 8 hours. Behavioral alterations, heart and respiratory rates were recorded. Nociceptive thresholds from these points were averaged to obtain mean values at each time, converted to a logarithmic scale, and submitted to a nonparametric analysis (Mann–Whitney and one‐way repeated measures anova test, p ≤ 0.05). Results After 8 hours, the global range score revealed reduced hyperalgesia (p < 0.01) around the incision in 92% (4.65–4.27) of evaluated intervals in group A (ketamine). There were no significant changes in behavior, heart and respiratory rates. Conclusions It was concluded that pre‐emptive epidural ketamine reduced post‐incisional pain in the horse, and that von Frey filaments were able to quantify cutaneous sensitivity after tissue damage. Clinical relevance Epidural ketamine injection can reduce post‐incisional sensitivity in the horse.  相似文献   
62.
应用适应于番鸭胚成纤维细胞(MDEFC)上繁殖,并产生细胞病变的鹅细小病毒(GPV)弱毒疫苗株与番鸭细小病毒(MPV)弱毒疫苗,按适当比例混合,试制了MPV-GPV二联弱毒细胞苗,并测定了各项免疫指标.结果显示试制出的二联苗对1日龄雏番鸭具有良好的安全性和遗传稳定性;免疫后5 d和7 d攻击GPV强毒,保护率分别为75%和100%,同时免疫后7 d血清中MPV-胶乳凝集抑制(LPAI)抗体效价均大于21,21~28 d抗体达高峰,有效免疫期超过60 d.疫苗于-20℃保存期大于12个月.上述结果表明,二联弱毒细胞苗安全有效.  相似文献   
63.
目的:本试验旨在研究铁苋菜提取物对仔猪生长性能、血液生化指标及粪样菌群的影响.方法:选取同一批次的25日龄健康的外三元断乳仔猪120头,平均体重为9.60+0.65 kg/头,随机分为4组,每组3个重复,每个重复10头,公母各半;试验组分别为铁苋菜提取物组Ⅰ和组Ⅱ、抗生素组及对照组,铁苋菜提取物组Ⅰ和组Ⅱ在基础日粮中分...  相似文献   
64.
Reproductive phenology is an important trait subjected to natural selection. Current horses in America belong to the Palearctic original populations after being introduced by European colonizers. Photoperiod variation is the main environmental factor for the adjustment of reproductive timing in horses, but is absent in equatorial areas. Here we hypothesize that seasonality of green‐grass availability may influence breeding phenology in equatorial regions. We used data of 929 services to mares from 2006 to 2011 in a thoroughbred equine exploitation in Ecuador that experienced strong grass seasonality. Actual births could not be used to infer natural phenology because they were influenced by management decisions. Instead, we used variations in the probability of pregnancy after a service as a measure of the natural tendency of mares to show breeding phenology. We found that although managers tended to schedule pregnancies in two periods within the year, mares were more prone to become pregnant after the increase in grass greenness that takes place at the beginning of the year (February). Our finding has potential applications to improve the success of services and the welfare of animals, by providing green‐grass stimuli in the appropriate season.  相似文献   
65.
披碱草属四种植物主要形态特征的变异性比较   总被引:2,自引:1,他引:2  
应用变异系数、主成分分析、系统聚类分析方法,对披碱草属四种不同生境来源的18个居群的180份材料进行形态特征比较分析.变异系数分析结果表明:(1)披碱草属4种植物的不同居群在形态特征上具有变异性;(2)不同居群内及居群间的形态特征存在一定程度的变异;(3)穗部形态特征中的颖及稃特征是种间和种以下分类的重要依据.主成分分析结果表明:颖长、颖脉数、外稃长、内稃长、小穗长、小穗宽等是种间分类的重要特征指标.系统聚类分析法分析表明:在欧式距离等于5时可将来自不同生境的18个居群分为3类,经鉴定第一类为披碱草和老芒麦,第二类为麦宾草,第三类是圆柱披碱草;其中麦宾草的归类清晰.  相似文献   
66.
Early embryonic loss (EEL) negatively affects the reproductive efficiency of equine reproduction. A sign of future EEL is when the embryo proper (EP) fails to develop within the embryonic vesicle after 30 days of gestation. The earlier the identification of impending EEL, the earlier the mare can be rebred to allow a second chance of pregnancy. The objectives of this study were to determine the percentage of embryonic vesicles with a visible EP at 18-28 days of gestation and to study the association between the presence/absence of the EP at different days of gestation and the future viability of the pregnancy. A total of 1,256 pregnancies were identified and followed by transrectal B-mode ultrasonography 12-45 days post ovulation in mares of the same Thoroughbred farm. The identification of the EP was attempted once during days 18-28. Pregnancy reconfirmation was performed on days 35-45. The percentage of vesicles with an EP increased gradually from days 18 (2.8%) to 21 (86.9%) (P < .05). From day 20 onward, the EEL rate of mares with vesicles without an EP was significantly higher (P < .05) than that of vesicles with a positive identification of an EP. In conclusion, the EP of the equine vesicle can be identified reliably with B-mode ultrasonography in the majority of mares (>71%) on day 20 of gestation. The lack of a positive identification of an EP from day 20 onward is associated with a higher EEL rate.  相似文献   
67.
采用常规尸解,石蜡切片、苏木精-曙红染色(H—E)、绦虫整体醋酸明矶洋红染色等方法’对一只病死蓝眼葵花鹦鹉的绦虫病原及肠道组织病理进行了初步研究。结果表明:该蓝眼葵花鹦鹉肠道内寄生有大量瑞氏绦虫,集结成团堵塞了肠道。肠道组织病理分析发现肠牯膜上皮部分组织坏死、脱落,小肠绒毛固有层、黏膜下层及浆膜内有充血、炎细胞浸润,显示该种绦虫对鹦鹉肠道组织造成了一定损伤,影响了鹦鹅对营养物质的消化吸收。  相似文献   
68.
羊肠毒血症又称软肾病,类快疫,是由D型魏氏梭菌在羊肠道内繁殖产生毒素所引起的羊急性传染病。2000年2月首先在我市小集镇赵庄发生,而后扩散到宋营、张庄、古庄、马庄等9个自然村,时有零星发生。现将诊治情况报道如下:1临床症状发病急,死亡快,大多数表现急剧水泻,行走不稳,继而卧地不起,双目凝视,呼吸困难,头向后仰,四肢伸直做急促的游泳动作。全身抽缩,有腹痛表现,最后哀叫痉挛而死。2剖检变化死尸迅速腐败膨胀,可视粘膜充血呈暗紫色。主要见真胃出血性炎症,胃底部及幽门部粘膜可见大小不等的出血斑点及坏死区。…  相似文献   
69.
作者从1999-2000年共解剖鄱阳湖草洲钉螺87146只,先后发现裸头类、矛口类、单盘类、微尾类、叉尾类、对盘类、无尾类尾蚴共15种,本文将各种尾蚴的形态特征予以简介。  相似文献   
70.
半干旱草原主要植物光能和水分利用特征的研究   总被引:15,自引:13,他引:15  
在植物生长季内测定了内蒙古半干旱草原6种主要植物的光合和水分利用特征,比较了植物之间在光能和水分利用方面的差异,认为水分利用效率难以反应植物对干旱的适应性,而其倒数-水分竞争系数是较好的表征指标;植物的光能利用效率和水分竞争系数之间存在补偿关系;半干旱草原主要植物适应环境的方式不同,它们在光能和水分资源生态位上存在分离。  相似文献   
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