Equine cardiovascular pathology: an overview

The few data collections that evaluate the involvement of organ systems in horse diseases are in agreement that the locomotor, gastrointestinal and nervous systems are the sites of primary disease in the vast majority of sick horses. When compared with diseases of these organ systems, equine cardiovascular diseases occur infrequently. The most detailed and comprehensive survey of equine cardiac pathology was reported in 1972 by Else and Holmes, who summarized the gross and microscopic cardiac findings from 1500 abattoir horses. This paper reviews the pathology of the cardiovascular diseases typically encountered in horses. Most of the pathological examples are from the files of the Veterinary Medical Teaching Hospital at the University of Florida, encompassing 24 years (1978-2002) and some 6000 equine necropsy cases. Preceding the specific topics are principles of the anatomy and function of the normal equine heart. Pathological entities include equine congenital cardiovascular diseases, acquired diseases of the pericardium, myocardium, endocardium and valves, cardiac neoplasms, and common equine vascular diseases and vascular neoplasms. Extensive use is made of photographs to illustrate the features of individual case examples.     

Swine vesicular disease: an overview

Swine vesicular disease (SVD) is a notifiable viral disease of pigs included on the Office International des Epizooties List A. The first outbreak of the disease was recognized in Italy in 1966. Subsequently, the disease has been reported in many European and Asian countries. The causative agent of the disease is SVD virus which is currently classified as a porcine variant of human coxsackievirus B5 and a member of the genus enterovirus in the family picornaviridae. From a clinical point of view, SVD is relatively unimportant, rarely causing deaths and usually only a minor setback to finishing schedules. However, the clinical signs which it produces are indistinguishable from those caused by foot-and-mouth disease, and its presence prevents international trade in pigs and pig products. This article reviews recent findings on all aspects of the virus and the disease which it causes.     

Electrophysiology in neuromuscular disease.

Electrophysiologic assessment of the peripheral nervous system is an integral part of the diagnostic workup for neuromuscular disease. This article is designed to provide insight into the importance and limitations of the various testing procedures now available in veterinary electrophysiology and to provide the reader with an understanding of the theory behind each of these procedures. The article also provides a guideline for the interpretation and clinical significance of each of the available tests.     

Caliciviruses: an overview.

Several caliciviruses are known to cause diseases in animal and man. Amongst them are vesicular exanthema virus of swine (VESV), feline calicivirus, rabbit hemorrhagic disease virus (RHDV), and Norwalk and Sapporo-like viruses; the latter viruses cause gastroenteritis in man. In this paper, an overview of caliciviruses is presented, with particular emphasis on the molecular aspects. The unique properties as compared to other related families of positive-stranded RNA viruses will be discussed. Many findings about the molecular biology of caliciviruses came from systems that are difficult to work with, such as RHDV, which can thus far only be propagated either in animals or in primary rabbit hepatocyte cultures. Therefore, the review will concentrate on RHDV.     

Equine arteritis virus: an overview.

The causative agent of the respiratory disease equine viral arteritis is a small, single-stranded RNA virus with a genome organization and replication strategy related to that of coronaviruses and toroviruses. Clinical signs of infection in horses vary widely and severe infection can lead to pregnant mares aborting. Infected horses generally make good recoveries but stallions may become semen shedders of equine arteritis virus (EAV). These carrier stallions play an important role in the dissemination and perpetuation of EAV. Laboratory tests exist to detect virus and the equine immune response to infection. However, vaccines are not currently licensed in the UK to combat viral arteritis, the incidence of which may increase due to changes in European legislation.     

Fungal diseases of amphibians: an overview.

Clinicians should be familiar with the most common fungal diseases of amphibians. Because lesions in mycotic diseases are nonspecific, a diagnosis cannot be established solely on the basis of clinical presentation. Bacterial, mycobacterial, chlamydial, and parasitic infections, and toxic or environmental conditions may mimic mycotic disease to various extents. Furthermore, mycoses may be masked by overwhelming secondary bacterial infection and therefore remain undiagnosed. Skin scrapings, impression smears, biopsies, and fungal culture are all useful tools in confirming or dismissing a diagnosis of mycosis. Whenever possible, an effort should be made to forward samples and biopsies for culture to appropriate laboratories. Providing the laboratory with a tentative etiologic diagnosis may allow for specific selection of more specific agars and culture conditions and maximize the chances of recovering the fungus from lesions. Identification to species level should also be encouraged, if progress is to be made in the understanding of mycoses in amphibians. The morphology of an isolate should be consistent with the microscopic features of the fungus in histological sections of affected tissues, if it is to be firmly incriminated as the cause of disease. A complete necropsy should be conducted on animals that die or are found dead, and, ideally, isolates from confirmed cases of fungal infection should be deposited in scientific collections, so that they are available for later studies. In addendum, readers should be aware that there is recent evidence to suggest that at least some published cases of amphibian basidiobolomycosis were in fact cases of chytridiomycosis [38], and therefore the validity of basidiobolomycosis as a disease entity in amphibians may be revisited in the years to come.     

Molecular diagnosis of inherited neuromuscular disease.

Prevention of inherited disease in companion animals is largely dependent on prebreeding identification of carriers of autosomal recessive disease traits. Molecular diagnosis is emerging as a convenient and reliable method of carrier detection, but few molecular diagnostic tests of inherited neuromuscular disease are readily available. New test development depends on investigations to determine disease genes and the disease causing mutations. A general approach to molecular diagnosis of inherited disorders is discussed.     

The clinical examination for neuromuscular disease.

Neuromuscular disease can present even the most astute clinician with a challenging diagnostic dilemma. This article focuses on the neuroanatomy and the historical, physical, and neurologic examination findings observed in many of the neuromuscular disorders affecting dogs and cats. In addition, some common laboratory tests and imaging modalities used in the diagnosis of neuromuscular disease, including routine radiography, computed tomography, and magnetic resonance imaging, are discussed. A brief discussion of sensory nerve disorders is also presented.     

Foot and mouth disease in Tanzania: an overview of its national status

The presence of foot-and-mouth disease (FMD) in Tanzania is a major obstacle to the development of the national livestock industry because of its adverse effects on livestock production and on trade of animals and animal products into lucrative export markets. FMD is endemic in Tanzania, the affected area is extensive and lack of funding makes eradication unrealistic. Uncontrolled livestock movements, the presence of large populations of wildlife in regular contacts with livestock, and the general lack of enthusiasm for FMD control among the key stakeholders, are some of the factors favouring the persistence of FMD in Tanzania. This review examines the epidemiology, dynamics and socio-economic significance of FMD in the national herd. Various control options available in Tanzanian context are also explored.     

Equine heart disease. An overview

The clinician must appreciate unique aspects of equine cardiovascular physiology in order to distinguish normal variation from a pathophysiologic state. Cardiovascular problems in the horse include auscultation of cardiac murmurs, identification of cardiac arrhythmias, and recognition of congestive heart failure. A cardiac data base including history, general and cardiovascular examination, and resting and postexercise electrocardiogram are necessary to evaluate most horses for significant heart disease. Additional studies, such as echocardiography and cardiac catheterization, are useful in selected cases. Because some types of heart disease are amendable by therapy, an accurate diagnosis is needed to direct treatment and offer a realistic prognosis.     

Prevalence of heart disease in symptomatic cats: an overview from 1998 to 2005

A total of 408 cats with various cardiovascular problems has been presented to two investigational clinics during the last 8 years. The number of yearly examinations has steadily increased during this period. Definitive cardiovascular disease was diagnosed in 287 cats, whereby hypertrophic cardiomyopathy (HCM) was the most common diagnosis with 67.6%. Congenital cardiovascular malformations were found in 11.8% of the cases. Ventricular septal defect (VSD) was the most frequent anomaly, in contrast to previously published studies. The ECG was found to be relatively non-specific and insensitive for the diagnosis of heart disease: Its usefulness lies in the recognition and diagnosis of cardiac arrhythmias. The radiographically recognized changes were also non-specific for certain heart diseases. Radiographs of the thorax are especially useful in the evaluation of cardiomegaly, and secondary signs of congestion.     

Antibiotic resistance: an overview

The results of large scale surveys have indicated that in general terms antibiotic resistance in bacteria has not increased, especially in Europe and North America. When the prevalence of resistance in specific bacteria has increased the increase has usually been associated with the introduction of a novel antimicrobial agent, whether in human or veterinary clinical practice, but the prevalence of resistance that is recognised may be very small. It would appear that the use of antibiotics in livestock farming during the past 20 years has not compromised public health. Any problems in human medicine which are due to bacterial resistance have resulted from the use of antibiotics in man and not from their use in agriculture. Similarly, any problems in veterinary medicine which are due to bacterial resistance have resulted from the use of antibiotics in animals and not from their use in man.     

BVD diagnosis: an overview

The first step and a crucial condition for the success of a control or eradication program for BVD (bovine viral diarrhea) is the identification and elimination of animals persistently infected with the virus. For this, besides detailed knowledge of the epidemiology, efficient diagnostic tests are necessary. This review summarizes the presently available diagnostic tests for detection of antibodies against the virus or for detection of viral components. Their performance and their applicability in eradication programs is discussed.