Fish lymphocystis disease virus (FLDV) has been tentatively classified as a separate genus of the iridovirus family. Iridoviruses were previously called icosahedral cytoplasmic deoxyriboviruses (ICDV). The Iridoviridae family contains four genera including lymphocystis disease virus (proposed name Lymphocystivirus, Willis, 1989 (1». FLDV is a causative agent of lymphocystis disease (LD) which frequently appears in Pleuronectidae (flatfish) such as Pleuronectes platessa (plaice), Platichtys flesus (flounder), Limanda limanda (dab), and Trigla gurnardus (gurnard). Fish lymphocystis disease is characterized by papilloma-like lesions, which can be induced experimentally in Lepomis macrochirus (bluegill) (2) and by subdermal injection of plaice and flounder (3). The mechanisms of this nonmalignant tumor induction are unknown. Since the discovery of LD in 1874 by Lowe (4), attempts have been made to isolate and propagate FLDV in vitro with limited success (5-7). As a first step towards understanding of the underlying mechanisms of this infectious disease the structure and properties of the causal virus must be eluciated. These basical molecular biological studies provide new facilities for investigation of virus host interactions which is necessary for understanding the molecular mechanisms of the viral pathogenesis. MATERIALS AND METHODS A total of 30 fish with LD lesions caught near the Doggerbank areas were analyzed individually, including 20 flounders, six dabs, and four plaice. Virions of FLDV from LD lesions of each species of fish were isolated, purified, and examined by electron microscopy as 205 described previously (8). Fig.

This is the first book on ranaviruses. Ranaviruses are double-stranded DNA viruses that cause hemorrhagic disease in amphibians, reptiles, and fish. They have caused mass die-offs of ectothermic vertebrates in wild and captive populations around the globe. There is evidence that this pathogen is emerging and responsible for population declines in certain locations. Considering that amphibians and freshwater turtles are suitable hosts and the most imperiled vertebrate taxa in the world, ranaviruses can have significant impacts on biodiversity and ecosystem function. Additionally, many fish that are raised in aquaculture facilities and traded internationally are suitable hosts; thus, the potential economic impact of ranaviruses is significant. Ranaviruses also serve as a model for replication and gene function of large double-stranded DNA viruses. There is an urgent need to assemble the contemporary information on ranaviruses and provide guidance on how to assess their threats in populations. Through the Global Ranavirus Consortium, 24 experts from six countries were organize to write this volume, the first book on ranaviruses. The book begins with a discussion on the global extent of ranaviruses, case histories of infection and disease in ectothermic vertebrates, and current phylogeny. Basic principles of ranavirus ecology and evolution are covered next, with a focus on host-pathogen interactions and how the virus emerges in its environment. There are two chapters that will discuss the molecular biology of ranaviruses, host response to infection, and the genes responsible for immune system evasion. One chapter establishes standards for testing for infection and diagnosing ranaviral disease. The book ends by providing guidance on how to design ranavirus surveillance studies and analyze data to determine risk, and discussing the role of the Global Ranavirus Consortium in organizing research and outreach activities.

The successful reproduction of cultured brood stock is essential to the sustainable aquaculture of aquatic organisms. This book describes recent advances in the field of finfish reproductive biotechnology. The chapters in this volume are written by eminent scientists who review the progress and assess the status of biotechnology research that is applicable to the reproduction of finfish species for aquaculture. A wide range of topics is included starting with broodstock technologies such as broodstock genetics, broodstock nutrition, environmental control of maturation and impacts of stress on broodstock, gametes and progeny. The volume includes technologies for induction of ovulation and spermiation using synthetic hypothalamic peptides. Gamete technologies which are described include cryopreservation, chromosome set manipulation, disease prevention and control for gametes and embryos and the development of transgenic fish with enhanced production characteristics. Genetic and endocrine technologies for the production of monosex male and female fish stocks are also described.The closing chapter summarizes the discussion of each topic at the workshop, provides recommendations to industry and describes priorities of research and development. Researchers as well as teaching faculty in the aquaculture field will find this volume of great value.

Aquaculture Virology, Second Edition covers all the known virus families, and specific diseases that affect each aquatic organism. Descriptions of each disease includes disease name, structure and composition of virus, classification and virus replication, epidemiology, pathology and immunity, diagnostic methods (gross pathology, histopathology, cell culture, PCR, sequencing, ELISA, etc.) and prevention and control. This is an excellent reference of updated foundational and practical knowledge from experts in both academia and research.Those interested in fish viral diseases will find the book an excellent source for high quality illustrations of viral structure, diagrams of pathogenesis of diseases, and many images of gross pathology and histopathology lesions, using the same format in all chapters to facilitate the reading and studying. This second edition of the book will cover all virus families and the specific diseases relevant to aquaculture with current information delivered in a systematic and succinct way to the researcher, teacher, student, diagnostic laboratory staff, clinical veterinarian, aquaculture disease practitioner, farmer, and all people that are interested in viruses in general. - Provides unique, comprehensive information on animal pathogens and viruses found in aquaculture and fisheries - Presents high-quality illustrations of viral structure, diagrams of viral disease processes, gross pathology, and histopathology lesions to aid in understanding - Incorporates all updated changes in taxonomy since the first edition - Includes a new chapter on the impact of climate change on the manifestations of different aquatic animal viral diseases - Describes aquatic viruses of the major aquatic animals, fish, crustaceans, and mollusks

New viral diseases are emerging continuously. Viruses adapt to new environments at astounding rates. Genetic variability of viruses jeopardizes vaccine efficacy. For many viruses mutants resistant to antiviral agents or host immune responses arise readily, for example, with HIV and influenza. These variations are all of utmost importance for human and animal health as they have prevented us from controlling these epidemic pathogens. This book focuses on the mechanisms that viruses use to evolve, survive and cause disease in their hosts. Covering human, animal, plant and bacterial viruses, it provides both the basic foundations for the evolutionary dynamics of viruses and specific examples of emerging diseases. - NEW - methods to establish relationships among viruses and the mechanisms that affect virus evolution - UNIQUE - combines theoretical concepts in evolution with detailed analyses of the evolution of important virus groups - SPECIFIC - Bacterial, plant, animal and human viruses are compared regarding their interation with their hosts

The past decade has witnessed an explosion of information on the molecular biology of insect viruses and a frenzy of activity in applying this information to medicine and agriculture. Genetically engineered baculoviruses are presently being tested for commercial use as pesticides, and the study of such viruses is also revealing remarkable insights into basic cellular processes such as apoptosis. This comprehensive volume provides readers with knowledge of basic and applied baculovirology so that current literature in the field can be appreciated.