Prolonged anesthesia using sevoflurane,remifentanil and dexmedetomidine in a horse

HistoryA 10–year old Arabian mare had a slow–growing mass on the lower right mandible and required a large partial mandibulectomy.Physical examinationNo abnormalities were detected apart from the mass.ManagementA temporary tracheostomy was performed pre–operatively. Anesthesia was induced with xylazine followed by ketamine and diazepam. For 13 hours, anesthesia was maintained using sevoflurane, dexmedetomidine and remifentanil infusions, with the exception of surgical preparation time. Intra–operatively, ventilation was delivered through the cuffed tracheotomy tube. Heart and respiratory rates, ECG, arterial pressures, inspired and expired gases, pulse oximetry values and body temperature were monitored. Dobutamine and whole blood were necessary, and romifidine was used to control recovery. Post–operatively, phenylbutazone and buprenorphine given systemically and bupivacaine administered through a wound soaker catheter were used to provide analgesia. Head–shaking from buprenorphine was controlled with acepromazine and detomidine once standing after 87 minutes in recovery. For 3 days after surgery, analgesia was provided with butorphanol, phenylbutazone and bupivacaine. The mare recovered well, appeared comfortable and started eating the following day with no signs of ileus.Follow–upSeven months later, the mare was doing well.ConclusionsSevoflurane, dexmedetomidine and remifentanil infusions were suitable for a long and invasive procedure.     

Heavy reliance on surrogate species and historical data may confound estimates of the sustainability of hunting in Papua New Guinea

Birds are among the most widely studied organisms on earth and represent an important indicator group for learning about the effects of climate change – particularly in regard to the effects of climate change on tropical ecosystems. In this review, we assess the potential impacts of climate change on tropical birds and discuss the factors that affect species’ ability to adapt and survive the impending alterations in habitat availability. Tropical mountain birds, species without access to higher elevations, coastal forest birds, and restricted-range species are especially vulnerable. Some birds may be especially susceptible to increased rainfall seasonality and to extreme weather events, such as heat waves, cold spells, and tropical cyclones. Birds that experience limited temperature variation and have low basal metabolic rates will be the most prone to the physiological effects of warming temperatures and heat waves. Mostly unknown species’ interactions, indirect effects, and synergies of climate change with other threats, such as habitat loss, emerging diseases, invasive species, and hunting will exacerbate the effects of climate change on tropical birds. In some models habitat loss can increase bird extinctions caused by climate change by 50%. 3.5 °C surface warming by the year 2100 may result in 600–900 extinctions of land bird species, 89% of which occur in the tropics. Depending on the amount of future habitat loss, each degree of surface warming could lead to approximately 100–500 additional bird extinctions. Protected areas will be more important than ever, but they need to be designed with climate change in mind. Although 92% of currently protected areas are likely to become climatically unsuitable in a century, for example only 7 or 8 priority species’ preferred climatic envelopes are projected to be entirely lost from the African Important Bird Area network. Networks of protected areas need to incorporate extensive topographical diversity, cover wide elevational ranges, have high connectivity, and integrate human-dominated landscapes into conservation schemes. Most tropical bird species vulnerable to climate change are not currently considered threatened with extinction, often due to lack of knowledge; systematically and regularly gathering information on the ecology, and current and future distributions of these species is an urgent priority. Locally based, long-term tropical bird monitoring and conservation programs based on adaptive management are essential to help protect birds against climate change.     

标准型、缺口型和螺旋缺口型圆盘耙性能比较（摘选）

对标准型、缺口型和螺旋缺口型圆盘耙性能分别在室内3个装有沙壤土的土槽测试耕作圆盘的性能。实验室测试设置包括土槽系统和数据采集系统。双扩展八角形环（DEOR）传感器和滑环扭矩传感器,用于三维应力和扭矩测量。圆盘角和旋转速度是研究对象。对于所有型式的圆盘耙而言,使用外源动力驱动都可以减少土壤作用在耕作圆盘耙上的合力。形态各异的切割边缘显著影响耕作圆盘耙的受力和对土壤的切削作用。螺旋缺口圆盘耙表现出比缺口和标准圆盘耙低的土壤作用。螺旋切削刃提供剪切割行动,消除冲击载荷,提供流畅的操作。由于其能对作物残留物进行有效切割,因此,螺旋缺口圆盘耙是适合保护性耕作作业最具潜力的机具。      

Cardiopulmonary effects of pleural insufflation with CO2 during two-lung ventilation in dorsally recumbent anesthetized horses

Objective

To record the cardiopulmonary effects of pleural CO₂ positive pressure insufflation in anesthetized horses.

Detection of Neospora caninum tachyzoites in cerebrospinal fluid of a dog following prednisone and cyclosporine therapy

Abstract: A 9‐year‐old female spayed Shetland Sheepdog was presented to the Kansas State University Veterinary Medical Teaching Hospital for evaluation following a 3‐week history of left rear limb lameness that had progressed to generalized ataxia. Multifocal or diffuse brain lesions were suspected based on physical examination findings. Cerebrospinal fluid (CSF) contained 52 nucleated cells/μL composed of mixed inflammatory cells. Treatment with prednisone and cyclosporine was initiated based on a presumptive diagnosis of granulomatous meningoencephalitis. Thirteen days later the dog was nonambulatory and mentally obtunded. Repeat CSF analysis revealed 298 nucleated cells/μL with 61% eosinophils. Rare protozoal tachyzoites consistent with Neospora caninum, Toxoplasma gondii, or Sarcocystis spp. were found extracellularly and within macrophages and an eosinophil. Despite cessation of prednisone and cyclosporine therapy and provision of supportive care, the dog died 6 days later. Examination of brain tissue sections revealed multifocally extensive, necrotizing, histiocytic, and lymphoplasmacytic meningoencephalitis with numerous protozoal zoites and cysts. Immunohistochemical analysis of brain tissue using a monoclonal antibody specific for N. caninum confirmed the diagnosis of neosporosis. Similar but less severe lesions were noted in the spinal cord, although organisms were not found. This case emphasizes the value of repeated CSF analysis when therapy is ineffective and the importance of excluding infectious causes of meningoencephalitis before commencement of immunosuppressive therapy.     

Defoliation induces root exudation and triggers positive rhizospheric feedbacks in a temperate grassland

The facilitating effect of the exudation of carbon (C) compounds from roots on rhizospheric processes has been shown in controlled experiments; however, it still remains unclear how important this pathway of C from plants to the soil may be in energy and nutrient processes in grazed grasslands under natural conditions. Root exudation may be a particularly important C pathway in grazed grasslands and help promote positive feedbacks between large herbivores and plants. In this study we performed a ¹³C pulse-chase experiment on plots that were clipped or left unclipped in a mesic grassland in Yellowstone National Park. The dominant grass species in the plots was Poa pratensis and it was used to measure the effect of defoliation on root C exudation, the rhizospheric microbial community, and feedbacks on plant nutrient uptake over a time period of 24–72 h. Defoliation stimulated C exudation from roots by 1.5-fold, which concomitantly increased rhizospheric microbial biomass by the same factor. The facilitating effects of defoliation on rhizospheric processes resulted in positive feedback on soil inorganic N pools and leaf N content, which increased by 1.2- and 1.5-fold respectively. Changes in soil inorganic N pools during the experiment indicated that the effect of the C flush on the rhizospheric decomposer community of defoliated plants resulted in a 5-fold increase in rhizospheric daily net N mineralization rate. These findings demonstrate that in a natural grassland community defoliation-induced stimulation of C exudation stimulates rhizospheric N-mineralization which ultimately benefits defoliated plants. The results also indicate the important role that short-term root–rhizospheric microbe interactions play in the C and N processes in grazed grasslands.     

Evaluation of Culicoides insignis (Diptera: Ceratopogonidae) as a vector of bluetongue virus.

Based upon epidemiological evidence, Culicoides insignis Lutz is a probable biological vector of bluetongue viruses (BTV) in South Florida, the Caribbean Region and Central America. The vector potential of this species for BTV was evaluated in the laboratory in a series of experiments using insects caught in the field. Although there was great variation in the percentage of flies that fed from any one catch, it was demonstrated that C. insignis became infected after membrane feeding on a mixture of blood and virus. The infection rates ranged from 20 to 62.5%. Following intrathoracic inoculation, BTV replicated to high titres in C. insignis. Such flies were also shown to be capable of transmitting BTV to susceptible sheep and embryonated chicken eggs. This series of experiments provides the first conclusive evidence that C. insignis is a biological vector of bluetongue virus. This is the first proven vector of BTV in the neotropics.