Computed tomography and magnetic resonance imaging of the equine musculoskeletal conditions.

There is a growing interest in the use of computed tomography (CT) and magnetic resonance (MR) imaging in equine orthopedic patients. It is well established that CT and MR imaging offer superior diagnostic information in a wide variety of musculoskeletal injuries in human beings and small animals. The highly detailed cross-sectional images obtained with these two modalities can often demonstrate pathologic changes undetected with other common imaging techniques. Based on their multiple applications in human beings and small animals, CT or MR imaging may prove to be the optimal diagnostic imaging technique for several types of musculoskeletal disorders of horses.     

Collateral arteries of the aortic arch of the red-rumped agouti (Dasyprocta leporina Linnaeus, 1758)

Detailed knowledge of the arterial system is an important prerequisite when interpreting experimental data in research, as well as in the diagnosis of cardiovascular disease using imaging techniques such as Doppler echocardiography and contrast radiography. Thus, considering the importance of the aortic arrangement, the objective of this study was to describe the collateral arteries of the aortic arch of agoutis in order to establish the standard model, and therefore contribute to studies involving research related to heart disease, and produce information for a more accurate diagnosis in complementary imaging examinations. In this study, 14 adult animals were used, comprising eight males and six females. The vascular system was washed with 0.9% aqueous saline solution and perfused with Neoprene 450 latex coloured with yellow or red pigment, which was subsequently dissected and analysed. One male animal was used for the digital contrast radiography technique perfused with a liquid barium sulphate solution (Bariogel^®) (1 g/ml) and Neoprene 450 latex, both diluted 1/3. The aortic arch of the agouti presented with only the brachiocephalic trunk as collateral branch in all the animals studied. Thus, agouti falls into type 1 for mammalian aortic arch vascular arrangements.     

链烷技术估测放牧动物牧草采食量与消化率

针对链烷技术的具体应用,分别就链烷作为指示剂的依据、链烷含量的分析及采食量与消化率的计算、指示剂选择等作一综述.重点讨论了用此方法估测放牧动物牧草采食量和消化率的影响因素,以使我国放牧动物研究中用此方法测定的采食量与消化率结果准确可靠.     

Accuracy of computed tomographic arthrography for assessment of articular cartilage defects in the ovine stifle

Articular cartilage defects are one of the features of osteoarthritis in animals and humans. Early detection of cartilage defects is a challenge in clinical veterinary practice and also in translational research studies. An accurate, diagnostic imaging method would be desirable for detecting and following up lesions in specific anatomical regions of the articular surface. The current prospective experimental study aimed to describe the accuracy of computed tomographic arthrography (CTA) for detecting cartilage defects in a common animal model used for osteoarthritis research, the ovine stifle (knee, femoropatellar/femorotibial) joint. Joints in cadaver limbs (n = 42) and in living animals under anesthesia (n = 13) were injected with a contrast medium and imaged using a standardized CT protocol. Gross anatomy and histological assessment of specific anatomic regions were used as a gold standard for the evaluation of sensitivity, specificity, negative predictive value, and positive predictive value for CTA identification of articular cartilage defects in those regions. Pooled estimated sensitivity and specificity were 90.32% and 97.30%, respectively, in cadaver limbs, and 81.82% and 95.24%, respectively, in living animals. Pooled estimated positive predictive value and negative predictive values were 98.25% and 85.71%, respectively, in cadaver limbs, and 81.82% and 95.24%, respectively, in living animals. The delineation of cartilage surface was good for anatomical regions most frequently affected by cartilage defects in the ovine stifle: medial femoral condyle, medial tibial condyle, and patella. This study supported the use of CTA as an imaging technique for detecting and monitoring articular cartilage defects in the ovine stifle joint.     

牛卵母细胞浆内单精子注射的研究进展

卵母细胞浆内单精子注射（ICSI）技术是20世纪80年代发展起来的一种人工辅助生殖技术。目前，ICSI技术已经成功的用于生产试管婴儿，治疗人类的男性不育。在牛上，ICSI技术主要用于生产性控胚胎以及受精机理和转基因的研究。作者综述了牛ICSI技术的研究现状和研究进展，重点讨论了牛ICSI技术的各种影响因素，阐述了ICSI技术目前存在的问题，并展望了ICSI技术的应用前景。     

Embryo transfer: its uses and recent developments

The technique of embryo transfer is now routinely employed in several species and with several objectives. In laboratory animals the technique is used mainly in investigations of reproductive biology, whereas in human beings it is used to overcome specific forms of impaired fertility. Because embryo transfer combined with superovulation of the donor can significantly increase the female reproductive rate its greatest application to date has been in farm animals, in which it is widely used in both research and commercial production. Within the past few years there have been many advances in the techniques used in farm animals, particularly in the area of embryo manipulation. The supply of embryos can now be increased by repeated superovulation and by embryo bisection and there has been significant progress in in vitro fertilisation technology. Deep freeze (-196 degrees C) storage of embryos is now routine and may be combined with direct one-step thawing and removal of cryoprotectant. This technique allows the routine non-surgical transfer of embryos in the field. There is also evidence that a routine non-traumatic procedure for sexing embryos may soon be developed. Identical multiplets or clones have been produced by the microdissection of embryos and more recently by the transfer of nuclei from embryos into unfertilized oocytes. Transgenic animals have been produced by the microinjection of recombinant DNA into one of the pronuclei of single-cell unfertilized ova.     

免疫组织化学技术在兽医诊断中的应用

免疫组织化学技术是利用抗原抗体特异性结合的原理,将物质标记在抗体上,通过标记来显示抗原抗体复合物的存在。随着免疫组织化学技术的发展和成熟,已被广泛应用于兽医诊断中,除用于对病原体准确的检测外,主要用于病原在机体组织中的定位和动态分布特点研究、新病原的发现、活体动物中病原的检测、以及对固定组织进行回顾性研究等,是广泛使用的现代病理学研究手段之一。     

FORENSIC RADIOLOGY AND IMAGING FOR VETERINARY RADIOLOGISTS

Imaging studies are often of evidentiary value in medicolegal investigations involving animals and the role of the veterinary radiologist is to interpret those images for courts as an expert or opinion witness. With progressing interest in prosecuting animal crimes and strengthening of penalties for crimes against animals, the participation of veterinary radiologists in medicolegal investigations is expected to increase. Veterinary radiologists who are aware of radiographic and imaging signs that result in animal suffering, abuse, or neglect; knowledgeable in ways radiology and imaging may support cause of death determinations; conversant in postmortem imaging; comfortable discussing mechanisms and timing of blunt or sharp force and projectile trauma in imaging; and prepared to identify mimics of abuse can assist court participants in understanding imaging evidence. The goal of this commentary review is to familiarize veterinary radiologists with the forensic radiology and imaging literature and with the advantages and disadvantages of various imaging modalities utilized in forensic investigations. Another goal is to provide background information for future research studies in veterinary forensic radiology and imaging.     

Cardioversion of atrial fibrillation in a dog with structural heart disease using an esophageal-right atrial lead configuration

Atrial fibrillation is a common arrhythmia in dogs with structural cardiac disease and can result in significant clinical signs. Several methods of electrical cardioversion of atrial fibrillation have been described. Biphasic transthoracic cardioversion of atrial fibrillation in dogs with naturally occurring heart disease has been described in veterinary medicine and has been shown to be highly successful. In humans and research animals intracardiac and transesophageal cardioversion of atrial fibrillation has been described as an alternative to transthoracic cardioversion. While transesophageal cardioversion is very successful in humans and research animals, this technique has not been previously described in a clinical patient with naturally occurring heart disease in veterinary medicine. This report describes the use of transesophageal cardioversion in a dog with atrial fibrillation and structural cardiac disease. Cardioversion was unsuccessful using two electrodes positioned within the esophagus. Cardioversion of atrial fibrillation to normal sinus rhythm was successfully achieved and maintained using one electrode positioned within the esophagus and one electrode positioned within the right atrium using a synchronized monophasic shock of 50 J.     

瘤胃液移植在反刍动物中的研究进展

瘤胃液移植是一种将健康供体动物的瘤胃液转移给受体动物的技术。目前，针对瘤胃液移植的报道还相对有限，但越来越多的研究结果显示，瘤胃液移植可以影响反刍动物的干物质采食量、产奶量等，还具有重建瘤胃菌群结构的潜力。本文综述了瘤胃液移植的方法及实践中的应用研究，分析其对反刍动物生长性能、瘤胃发酵、瘤胃微生物区系的影响以及在治疗某些疾病方面的作用，为反刍动物瘤胃液移植的研究提供参考。     

Clinical Update on Diagnosis and Management of Disorders of the Digestive System of Reptiles

The diagnosis and treatment of digestive system disorders in reptile species continues to provide challenges owing to the differences in anatomy and physiology in this diverse group of animals. Continued research efforts into diagnostic techniques, in particular imaging (e.g., contrast radiography and ultrasonography), of gastrointestinal tract have resulted in clinical advancements for practicing veterinarians. The aim of this article is to provide veterinarians up-to-date and clinically relevant summaries on the diagnosis and therapy of digestive system disorders of reptiles commonly maintained as companion animals.     

家畜性别控制技术的研究进展

在畜牧生产中,人为控制出生家畜的性别可以降低生产成本,提高经济效益。随着科技的进步和研究的不断深入,家畜性别控制技术也在不断的完善。作者综述了X、Y精子的分离和胚胎性别鉴定这两项家畜性控技术的发展历程和研究现状,并对其今后的研究方向及应用前景进行了展望。     

Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis

In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals.     

Current concepts in the diagnosis and treatment of brain tumours in dogs and cats

Intracranial tumours occur relatively frequently in dogs, and less commonly in cats. With the availability of computed tomography (CT) and magnetic resonance imaging, more accurate determination of the location and extent of brain tumours in companion animals has become possible. Following these advances in imaging, precise CT-guided stereotactic techniques for both tumour biopsy and intratumoral drug delivery have been developed for use in cats and dogs. Also, tumour identification methods, such as crush preparation examination, have facilitated rapid tumour identification. The use of improved diagnostic techniques has resulted in an increasing demand for effective therapies for brain tumours. While surgical removal and irradiation remain important treatment considerations in the management of brain tumours of cats and dogs, the development of gene therapy strategies for treatment of intracranial tumours offers much promise, although research in this area is still at an early stage.     

DCE‐MRI: a review and applications in veterinary oncology

Dynamic contrast enhanced magnetic resonance imaging (DCE‐MRI) is a functional imaging technique that assesses the physiology of tumour tissue by exploiting abnormal tumour microvasculature. Advances made through DCE‐MRI include improvement in the diagnosis of cancer, optimization of treatment choices, assessment of treatment efficacy and non‐invasive identification of prognostic information. DCE‐MRI enables quantitative assessment of tissue vessel density, integrity, and permeability, and this information can be applied to study of angiogenesis, hypoxia and the evaluation of various biomarkers. Reproducibility of DCE‐MRI results is important in determining the significance of observed changes in the parameters. As improvements are made towards the utility of DCE‐MRI and interpreting biologic associations, the technique will be applied more frequently in the study of cancer in animals. Given the importance of tumour perfusion with respect to tumour oxygenation and drug delivery, the use of DCE‐MRI is a convenient and powerful way to gain basic information about a tumour.     

Optical coherence tomography for the evaluation of retinal and optic nerve morphology in animal subjects: practical considerations

Optical coherence tomography (OCT) is a noninvasive, noncontact imaging technique capable of producing high-resolution images of the retina and optic nerve. These images provide information that is useful for following the progression and/or resolution of posterior segment disease. Rapid advances in OCT technology allow the acquisition of increasingly detailed images, approaching the original goal of providing in vivo histopathology. Increases in scan acquisition speeds and axial resolution enhance the clinical diagnostic value of this modality. Adapting instrumentation designed for use in human patients for use in animals can be challenging. Each species has a unique set of adjustments that need to be made but it is possible to obtain reproducible, high-quality OCT images in a variety of animals, including rodents, dogs, cats, pigs, and monkeys. Deriving quantitative measurements from OCT instruments is hindered by software algorithm errors in detecting the edges of the distinct retinal layers. These segmentation errors occur in scans of human eyes as well in other species and arise with similar frequency with each of the different OCT instruments. Manual segmentation methods to derive optic nerve head and other structural indices have been developed for several species.     

CARDIAC MAGNETIC RESONANCE IMAGING IN NORMAL DOGS AND TWO DOGS WITH HEART BASE TUMOR

We describe the technique for in vivo cardiac‐gated magnetic resonance imaging (MRI) in normal dogs and its application in two dogs with a large right atrial tumor. The dogs with a cardiac tumor were also imaged using contrast‐enhanced magnetic resonance angiography (CE‐MRA). Cardiac‐gated MRI and CE‐MRA are both feasible in animals with short acquisition times compatible with breath‐hold imaging under anesthesia, and provide detailed two‐ and three‐dimensional (3D) depiction of the cardiac anatomy and great vessels with or without contrast medium. Although cardiac MRI will not replace echocardiography, it is a powerful alternative technique to use when knowledge of the 3D anatomy of the vasculature is required, when precise volume measurements are needed or when myocardial characterization is indicated. As opposed to contrast‐enhanced computed tomography angiography, cardiac MRI does not use ionizing radiation or iodinated contrast medium.     

Pulmonary thromboembolism

Objective – To review the pathophysiology, clinical signs, diagnosis, and treatment of pulmonary thromboembolism (PTE) in small animals. Data Sources – Human and veterinary clinical studies, reviews, texts, and recent research in canine and feline PTE diagnosis and thromboembolic therapeutics. Human Data Synthesis – In humans, clinical probability assessment and point‐of‐care D‐dimer‐based algorithms are widely used. Computed tomography pulmonary angiography is the gold standard for PTE diagnosis in humans. Echocardiography is increasingly used for bedside assessment of affected patients. In low‐risk human patients anticoagulants alone are recommended while patients with cardiogenic shock are treated with thrombolytics followed by anticoagulation. Veterinary Data Synthesis – PTE is associated with numerous predisposing conditions causing hypercoagulability, blood flow stasis, or endothelial injury. Identifying at‐risk patients is key to diagnosis in small animals. Thromboelastography provides a method for identifying hypercoagulable patients. Computed tomography pulmonary angiography may replace selective pulmonary angiography as the imaging technique of choice for PTE diagnosis. PTE therapy consists of supportive treatment combined with appropriate, individualized thromboembolic pharmacotherapy for acute treatment and chronic management. Thrombolytic therapy for PTE remains controversial but may be indicated in hemodynamically unstable acute PTE. Thromboprophylaxis in specific conditions is rational although evidence of efficacy is limited. Prognosis depends upon degree of cardiopulmonary compromise and patient response to therapy. Mortality rates in small animals are unknown. Conclusions – New diagnostic techniques and advances in therapy offer significant potential for improvements in the identification and treatment of PTE in small animals. Further study must be directed to validating new diagnostic modalities and evaluating therapeutic regimes.     

Computed tomography in small animals--basic principles and state of the art applications

Since its clinical introduction, computed tomography (CT) has revolutionized veterinary medicine and is considered to be one of the most valuable tools for the imaging work-up of neurological, oncological and orthopaedic canine and feline patients. In small animals with acute trauma, particularly those involving complex anatomic areas such as the head, spine or pelvis, CT has been established as a standard imaging method. With the increasing availability of radiation therapy in veterinary medicine, CT has also become the principal tool to stage a tumour, assess response, and guide radiation therapy. The increasing availability of helical CT in veterinary medicine has allowed novel techniques such as spiral CT angiography and high-resolution CT. This review provides a brief overview of the historical and technical development of CT and literature reviews of the major clinical CT applications in small animals such as intracranial and extracranial lesions, the spine, the appendicular skeleton, and abdominal and thoracic diseases.