Butorphanol Tartrate for Partial Reversal of Oxymorphone-Induced Postoperative Respiratory Depression in the Dog

A randomized, blinded, crossover study was designed to evaluate the respiratory, cardiovascular, and behavioral effects of butorphanol given postoperatively to oxymorphone-premedicated and surgically stimulated dogs. Nine healthy adult dogs were premedicated intramuscularly with atropine (0.04 mg/kg), acepromazine (0.10 mg/kg), and oxymorphone (0.2 mg/kg). Anesthesia was induced with thiamylal (12 mg/kg) and maintained with halothane in oxygen. According to the protocol of a concurrent study, all dogs had percutaneous endoscopic gastrostomy (PEG) feeding tubes placed during the first anesthetic episode and removed during the second anesthetic episode. All dogs received postoperatively either butorphanol tartrate (0.2 mg/kg) or an isovol-umetric dose of saline placebo, both given intravenously. Respiratory rate (RR), tidal volume (TV), minute ventilation (MV), end-tidal CO₂ concentration (ET_CO2). heart rate (HR), and indirect diastolic (DP), systolic (SP) and mean arterial (MAP) blood pressures were measured at times 0, 2, 5, 10, 20, 40, 80, and 120 minutes after injection. The time from injection of the test drug until extubation was recorded. RR, MV, HR, and DP were significantly ( P < .05) increased, while ET_co2 was significantly decreased, for a minimum of 30 minutes in butorphanol-treated dogs compared with saline controls. TV, SP, and MAP were transiently (≤15 minutes) increased in butorphanol-treated dogs compared with saline controls. There was no significant difference between the times to extubation in the butorphanol-treated dogs versus the saline control dogs.     

The Hemodynamic Response of Calves to Tiletamine-Zolazepam Anesthesia

Six isoflurane-anesthetized calves were instrumented for hemodynamic studies and allowed to recover from anesthesia. When the mean arterial blood pressure rose to 100 mmHg or when vigorous movement occurred, a 1:1 tiletamine-zolazepam mixture (4 mg/kg) was administered intravenously (IV). Values for cardiac output, cardiac index, stroke index, central venous pressure, and right ventricular stroke work index did not change significantly. Systolic, mean, and diastolic arterial blood pressures and systemic vascular resistance were significantly decreased below baseline at 5 minutes; they were significantly increased above baseline at 20 minutes and remained so throughout the 60 minute study. Changes in left ventricular stroke work index and rate pressure product were similar to those of arterial blood pressure and systemic vascular resistance, although they were not significant. Heart rate and pulmonary capillary wedge pressure decreased significantly but gradually returned to baseline at 40 minutes and then increased significantly above baseline by the end of the study. Minor venous-arterial shunting or perhaps mismatching of ventilation and perfusion appeared to have developed in the later stages of the study. This was reflected in a minor increase in the arterial partial pressure of carbon dioxide (PaCO2) and a decrease in the arterial partial pressure of oxygen (PaO2) and arterial pH. At the dose administered, the hemodynamic changes induced by tiletamine-zolazepam were minimal and were compatible with safe anesthesia in calves.     

The Response of Cattle and Sheep to Feed Contaminated with Rodent Faeces

On farms where rats and mice are present, unprotected livestock feed may become contaminated with rodent faeces, thereby creating a possible source of infection for cattle and sheep. Livestock unable to avoid contaminated feed may choose to eat it entirely, reject it completely or attempt to reject faeces selectively while consuming some of the feed. Two experiments were conducted to investigate which of these three responses were demonstrated by livestock. Ten cattle and ten sheep were presented individually with three repeats of ten feed treatments. Treatments were based on two feed types (meal and pelleted compound), with three levels of contamination (none, 'low' and 'high'), from one of two rodent species (rat and mouse).Avoidance behaviour was greater for feed contaminated with rat faeces compared to feed contaminated with mouse faeces. At low levels of rat contamination there was evidence that livestock actively rejected faeces whilst consuming feed. At higher levels of contamination animals rejected faeces and feed. Livestock could not actively discriminate against mouse faeces and thus rejection of feed was used to avoid faeces ingestion.Despite rejection of contaminated feed and some discrimination against faeces, significant numbers of rodent faeces were ingested illustrating that livestock feeding behaviour cannot prevent ingestion of rodent faeces. Feed contaminated with rodent faeces therefore poses a significant risk of disease infection to livestock.     

Anesthesia and Cardiopulmonary Bypass Technique in Calves and Sheep

The number of research institutions using calves and sheep as models for open heart surgical procedures is increasing. The Artificial Heart Laboratory of the University of Utah has developed an effective protocol for thoracic procedures in these animals. Routine barbiturate induction and maintenance with fluothane and a pressure-regulated ventilator have minimized anesthetic problems. A membrane oxygenator with blood flows of 50 to 75 ml/kg body weight/min. seems to give adequate circulatory support during heart-lung bypass. Although animals implanted with total artificial hearts do not have problems with arrhythmias, changes in pulmonary function and peripheral vascular tone can alter their cardiac performance. The judicious use of ventilatory support and specific vasoactive drugs can significantly improve the animal's intraoperative blood pressure and postoperative arterial gases. A summary of the techniques and drugs which were used successfully in 187 of 189 animals during a 2 year period are presented.     

Cardiovascular and Pulmonary Effects of Sevoflurane Anesthesia in Horses

The effects of 1.0, 1.5, and 2.0 minimum alveolar concentration (MAC) of sevoflurane on hemodynamic, pulmonary and blood chemistry variables were measured during spontaneous and controlled ventilation in healthy horses. Sevoflurane was the only anesthetic drug administered to the horses. In a dose-dependent manner, sevoflurane significantly decreased ( P <.05) mean arterial blood pressure, cardiac output, and stroke volume. There was a progressive decrease in peripheral vascular resistance and an increase in heart rate as the concentration of sevoflurane was increased, but the differences were not significant. During spontaneous ventilation there was a dose-dependent decrease in respiratory rate that caused a decrease in the minute volume. As the dose of sevoflurane increased, the arterial carbon dioxide tension also increased ( P <.05). All blood chemistries remained within normal limits. Recovery from anesthesia was without incident. In conclusion, sevoflurane induces a dose-dependent decrease in hemodynamic variables and pulmonary function in horses that is not greatly different from that of other approved inhalant anesthetics.     

羊口疮疫苗对兔体液免疫和细胞免疫的影响

为深入研究羊口疮疫苗诱导机体产生免疫效应的分子机理,用羊口疮疫苗免疫兔,并对其血清中的特异性抗体水平和外周血免疫相关细胞因子的表达水平进行研究。将500 m L灭活的羊口疮病毒感染细胞毒液和经超声波破碎的灭活羊口疮病毒感染细胞毒液分别浓缩至100 m L,按照佐剂说明书比例,分别与弗氏佐剂、201VG、1313VG、GEL01、11R VG混匀。另外,取灭活的羊口疮痂皮毒液10 m L与201 VG混匀,制备成疫苗。用所制备的不同佐剂疫苗各免疫2只兔子。在免疫后不同时间采集外周血,应用琼脂免疫扩散方法检测血清中特异性抗体效价,同时应用实时荧光定量PCR方法检测外周血中细胞因子表达水平。结果显示:在兔子接种羊口疮疫苗后期,血清中抗体效价除了"1313VG+未破碎病毒"组为1:8之外,其他组别的抗体效价均达到1:16或1:32;各组别外周血中Th1型细胞因子(IL-2、IFN-γ、TNF-α)的表达量与对照组相比总体上升,而Th2型细胞因子(IL-4、IL-6)的表达量总体呈下降趋势。结果表明,羊口疮疫苗可以同时诱导机体产生细胞免疫应答和体液免疫应答,但对该两种免疫应答的诱导水平不同。     

国产赛福丁对绵羊的毒性及治疗绵羊痒螨病的效果

应用国产赛福丁对3组绵羊(每组3只)分别以10、20、40 mg/kg剂量进行了毒性试验。结果,10、20 mg/kg剂量的绵羊,药后临床未出现任何毒性反应;40 mg/kg剂量的绵羊,均于药后40～60 min出现了典型的有机磷中毒症状。全血胆碱酯酶对赛福丁非常敏感,但其抑制程度与中毒靠状的出现并无直接关系。中毒后血清GOT和GPT无变化。以50、100、200、250 ppm浓度的赛福丁溶液分别药浴患痒螨绵羊,均可迅速地治愈患羊,浴后24 h即可杀灭全部螨虫,24～72 h痒觉消失,2周后脱痂,长毛。近期疗效同于倍特和林丹.而远期疗效优于倍特和林丹。证明国产赛福丁是一种高效、低毒的杀螨剂。     

绵羊生产系统对不同放牧制度的响应

在1990～1997年定量放牧基础上,分别就绵羊生产性能对放牧率的反应、草-畜互作关系对放牧管理方式的响应、不同放牧制度对绵羊食性的影响、放牧绵羊的食量与营养需要进行了论述.     

Assessment of Expert Opinion: Seasonal Sheep Preference and Plant Response to Grazing

Expert opinion was sought on 2 issues relating to herbivory: seasonal sheep preferences for plant species and seasonal plant response to grazing. Expert opinion is commonly used to parameterize models: it is therefore important to assess its quality. Understanding the limitations of expert knowledge can allow prioritization of future research. Nine experts in plant or grazing ecology from Scotland/Northern England were individually interviewed. The experts ranked sheep preferences for species in 4 rangeland vegetation types and provided categorical information on plant response to grazing. For both issues, seasonal information was collected. Uncertainty (unanswered questions) on plant responses was much higher than uncertainty on sheep preferences. Uncertainty on sheep preference was significantly negatively correlated with plant species commonness, but not with quantity of scientific literature. Uncertainty on plant responses was significantly negatively correlated with both plant commonness and literature. There was agreement among experts on sheep preferences; standardized seasonal information for selected plant species is presented. In general, experts considered graminoids to be preferred over dwarf shrubs, with forbs and other species groups intermediate. Seasonal variation in sheep preference was greater for heath and mire than for grasslands. There was limited agreement among experts on seasonal plant responses. Some experts considered grazing in summer to affect growth more than grazing in winter, whereas others thought season had little effect. Sufficient agreement was found at the species level to present results on plant responses. Experts considered graminoids more resilient to grazing than dwarf shrubs. Experts agreed on sheep preference at different times of year, and on the overall resilience of plant species to grazing. However, the experts held 2 paradigms on the impact of seasonal grazing. Further research is required to explore this, because seasonal grazing regimes are currently promoted as conservation management tools.     

Response of Corriedale and Crioula Lanada Sheep to Artificial Primary Infection with Haemonchus Contortus

Clinical, parasitological and biochemical parameters were evaluated in Corriedale and Crioula Lanada sheep after a single experimental infection with Haemonchus contortus. Ten 4-month-old worm-free lambs, of each breed, were infected with 200 L₃ H. contortus per kg live weight and four uninfected animals of each breed were used as controls. Every week, the animals were weighed and blood and faecal samples were collected for measurement of packed cell volume (PCV), total serum protein (TSP) and albumin (ALB), and the number of eggs per gram of faeces (EPG), respectively. Twelve weeks after infection, the animals were slaughtered. The worm burden was determined and samples of the abomasal mucosa were processed for determination of the number of eosinophils, mast cells and globule leukocytes. No significant differences in PCV, TSP, ALB, parasite burden or the cell populations of the abomasal mucosa were observed between breeds, but Crioula lambs had a lower EPG count. The comparison of the infected groups with their respective controls revealed significant alterations in PCV, TSP and ALB in the Corriedale lambs and in PCV, TSP, ALB and the density of eosinophils and mast cells in the Crioula lambs.     

Feed Intake and Performance of Sheep Grazing Semiarid Grassland in Response to Different Grazing Systems

Effects of grazing management systems (GS) on biomass production and nutritional quality of rangeland vegetation in semiarid regions are extensively studied; however, limited information is available regarding their effects on diet digestibility and feed intake of grazing livestock. We therefore analyzed digestibility of ingested organic matter (dOM), organic matter intake (OMI), and live weight gain (LWG) of sheep in a grazing experiment established in the Inner Mongolian steppe of China, where two GS were tested for six different grazing intensities (GI) from very light to heavy grazing. For the continuous grazing system, sheep grazed the same plots each year, and for the alternating system, grazing and hay making were alternated annually between two adjacent plots. In July, August, and September 2009 and 2010, feed intake and live weight of sheep were determined. The GS did not affect dOM (P = 0.101), OMI (P = 0.381), and LWG of sheep (P = 0.701). Across both GS LWG decreased from 98 g · d^-1 for GI1 to 62 g · d^-1 for GI6 (P &spilt; 0.001; R² = 0.42). There were no interactions between GS and GI for all measured parameters (P ≥ 0.061), indicating that alternating grazing did not compensate for negative effects of heavy grazing even after 4 yr of grassland use. In summary, our study showed that irrespective of GI, alternating grassland use does not improve dOM, OMI, and hence, LWG of sheep. However, it might enhance revenues and ecological sustainability in the long term when compared to the common practice of continuous grazing at very high stocking rates.     

Cardiovascular Function and Serum Catecholamine Concentrations after Anesthesia and Surgery in the Dog

Peripheral vasoconstriction and plasma catecholamine concentrations were studied in 37 dogs after cervical disc fenestration and salivary gland excision, laparotomy for intestinal anastomoses and cystotomy, or laparotomy for repair of diaphragmatic rupture, gastrotomy, and pyloromyotomy. Meperidine (4.4 mg/kg) was administered before extubation of 12 dogs undergoing laparotomy. Heart rate, respiratory frequency, indirect blood pressure, rectal temperature, toe web temperature, and plasma concentrations of epinephrine and norepinephrine were determined before induction of anesthesia, after intubation, after extubation, at sternal recumbency, and at standing. All dogs were hypothermic during surgery. After surgery, peripheral hypothermia (large rectal-toe web temperature gradients) increased from a mean of 4.6 degrees C after intubation to a mean of 10.4 degrees C when the dogs initially stood. Heart and respiratory rates and blood pressures during recovery were similar to those before anesthesia. Mean plasma catecholamine concentrations were neither significantly higher during recovery than before surgery nor were they increased in any surgical group, including the dogs not treated with meperidine. After anesthesia, 15% of the epinephrine and 12% of the norepinephrine samples were more than two standard deviations above the mean of the preanesthetic concentrations of all dogs. The ratio of all dogs with an epinephrine concentration more than two standard deviations above the mean of baseline epinephrine concentrations was greater at sternal recumbency than before anesthesia and the ratio of dogs with an increased epinephrine concentration at sternal recumbency was greater in the laparotomy dogs (9 of 24) than in the cervical surgery dogs (0 of 12).(ABSTRACT TRUNCATED AT 250 WORDS)     

Sedation and Pain Management with Intravenous Romifidine−Butorphanol in Standing Horses

The objective of this study was to determine the sedation, analgesia, and clinical reactions induced by an intravenous combination of romifidine and butorphanol in horses. The study was conducted on six saddle horses weighing 382 to 513 kg (mean ± SD; 449 ± 54 kg) and aged 6 to 14 years. The horses each underwent three treatments: intravenous romifidine 0.1 mg/kg body weight (RM; mean dose, 4.5 mL); intravenous butorphanol 0.05 mg/kg body weight (BT; mean dose, 2.4 mL); and intravenous romifidine 0.1 mg/kg body weight plus butorphanol 0.05 mg/kg body weight (RMBT; mean dose, 7.0 mL). The order of treatments was randomized. Heart rate, arterial pressure, respiratory rate, rectal temperature, sedation, and analgesia were measured at two times before treatments, 15 minutes apart (times –15 and 0) and at 5, 10, 15, 30, 45, 60, 75, 90, 120, 150, and 180 minutes after drug administration. The onset of sedation was approximately 5 minutes after intravenous injection of RM and RMBT, whereas BT did not present this effect. The duration of complete sedation was approximately 60 minutes for RMBT and approximately 35 minutes for RM. The RMBT treatment provided 30 minutes and the RM treatment 20 minutes of complete analgesia. Heart rate decreased significantly (P < .05) from basal values in the RM and RMBT treatments. Only RM caused significant decreases (P < .05) in the respiratory rate. Arterial pressure did not change significantly (P > .05) in any treatment. Intravenous administration of a romifidine−butorphanol combination to horses resulted in longer duration of sedation and analgesia than administration of romifidine or butorphanol alone. These effects probably resulted from a synergistic effect of the two drugs.     

荒漠草原短花针茅表型性状对模拟绵羊采食的可塑性响应

为探讨短花针茅(Stipa breviflora)表型性状对模拟绵羊采食的可塑性响应,本研究设置对照(CK)、刈割(C)、模拟绵羊采食(CS)三个处理,测定短花针茅叶长、叶宽、单叶面积等11个表型性状,分析其不同处理下的差异性及可塑性。结果表明：与对照相比,刈割显著增加了短花针茅的比叶面积(P<0.05),模拟绵羊采食显著增加了短花针茅的单叶面积、比叶面积和株丛茎,显著降低了单叶质量、比叶质量和地上生物量(P <0.05);地上生物量、单叶质量和比叶质量是对刈割和模拟绵羊采食响应的敏感性状;单叶面积、平均叶长,株高及株丛径是对刈割和模拟绵羊采食响应的惰性性状;短花针茅地上生物量与分蘖数、单叶质量、比叶质量及株丛径呈极显著正相关(P<0.01),与株高呈显著正相关(P <0.05)。由此可见,短花针茅在模拟绵羊采食下产生的可塑性是其生存繁殖的重要反应机制之一。     

无角陶赛特羊与藏系羊杂交试验

无角陶赛特公羊杂交藏系母羊 3 5 0 0只 ,受胎率为 87% ,产羔 2 95 5只 ,羔羊繁活率为 75 % ;藏羊繁活率为 80 %。陶×藏F1的初生重、断奶重和 6月龄重比同龄藏系羊羔羊分别高 8 15 %、4 76%和 2 4 5 0 % ,差异显著 (P <0 0 5 )。陶×藏F1的屠宰前活重和胴体重比同龄藏系羊羔羊分别高 3 68kg和 2 2 4kg ,差异显著 (P <0 0 5 ) ,屠宰率提高了 4 1个百分点。