Download or read book Bovine Leukosis Virus BLV in U S Beef Cattle written by and published by . This book was released on 1999 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bovine Leukosis Virus BLV in U S Beef Cattle written by United States. Animal and Plant Health Inspection Service and published by . This book was released on 1999 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bovine Leukemia Virus in Beef Cattle written by Oscar Javier Benitez Rojas and published by . This book was released on 2019 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chronic lymphoproliferative disorder, bovine leukosis, is caused by the deltaretrovirus bovine leukemia virus (BLV). Surveys indicate that 39% of the US beef cow-calf operations have at least one BLV-infected animal compared with 83% of dairy herds. Most BLV infected cattle remain asymptomatic and act as carriers of the virus while less than 5% progress to lymphosarcoma. There are limited studies on the impact of BLV in beef cattle. Understanding the impact as well as identifying important route of disease transmission in beef cattle enterprises is important to better design intervention strategies. The primary goals of the studies described in this this dissertation were to 1) further understand the risk of breeding bulls in the transmission of BLV and 2) to determine the effect of BLV on the survival of cattle in beef and dairy herds. We first determined BLV prevalence in breeding beef bulls and the presence of BLV provirus DNA in genital secretions (smegma and semen). In our study population, 44.6% of beef bulls were seropositive for BLV and 48.7% of herds had at least 1 BLV-infected bull. Bovine leukemia virus provirus DNA was detected in smegma samples of 4/54 (7.4%) BLV-seropositive bulls and represent a potential risk for the transmission of BLV from infected bulls to uninfected cows during natural service breeding programs. To evaluate this risk, we exposed BLV negative heifers to a BLV positive bull during a defined 38-day breeding period. Although BLV provirus was found in the smegma and blood of the BLV positive bull prior to and after the breeding period, we detected no evidence of seroconversion or presence of BLV provirus DNA in the blood of naive heifers. These results suggest that BLV infected bulls that are healthy and aleukemic may not be a significant risk of BLV transmission during a defined breeding season.We next evaluated the impact of BLV infection on beef and dairy cow' longevity within herds. The presence of BLV antibodies in blood was not associated with a change in beef cow longevity over 2 years monitoring period, but decreased survival was observed in cattle in which BLV infection had advanced clinically as indicated by a high BLV provirusload in blood. In dairy cows, we demonstrated that infected females lived significantly shorter than their negative herd mates and were at a 30% greater hazard of being culled compared with BLV negative cows. In summary, there is high prevalence of BLV in breeding beef bulls which could serve as a source of transmission both within and between herds. Based on our study results, the risk of transmission of BLV from healthy infected bulls to naive heifers is low when bulls are housed with heifers for a defined breeding period, but this scenario should not be considered without risk. BLV does not appear to have an impact on beef cow longevity, but in contrast, is associated with decreased longevity in dairy cows. These studies provide important information for supporting and designing risk based BLV control programs.

Download or read book An Introduction to Survival Analysis Using Stata Second Edition written by Mario Cleves and published by Stata Press. This book was released on 2008-05-15 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: "[This book] provides new researchers with the foundation for understanding the various approaches for analyzing time-to-event data. This book serves not only as a tutorial for those wishing to learn survival analysis but as a ... reference for experienced researchers ..."--Book jacket.

Download or read book Decreasing Perinatal Bovine Leukosis Virus Infection in Calves written by Dusty W. Nagy and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bovine leukosis virus (BLV) is an oncogenic retrovirus of cattle that causes lymphosarcoma in a proportion of infected individuals. Currently the United States estimates are that 44% of dairy cattle and 10% of beef cattle are infected with the virus. Many states have voluntary control programs in place, but no mandatory or federal programs currently exist. This is dramatically different from many other industrialized, cattle producing countries that have government controlled, mandatory control and eradication programs in place. The inability to accurately detect infection in calves by serologic test methods due to the interference of colostral immunoglobulin has led to US control programs focusing on the identification of infected adults. The ease at which serologic methods can be used in adults has also removed attention from the potential role that persistent lymphocytosis may play on an infected premise. The goal of this body of work was to develop alternative methods that may be utilized on heavily infected farms to help in the control of BLV infection. The studies presented here focus on the utility of diagnostic tests in the identification of infected calves and the identification of adults with persistent lymphocytosis. Serology, PCR, and the detection of lymphocytosis all have a place in control programs although the tests should not be used interchangeably. It is possible that providing colostrum with BLV specific antibodies is protective against infection in neonatal calves.

Download or read book Enzootic Bovine Leukosis and Bovine Leukemia Virus written by A. Burny and published by Springer Science & Business Media. This book was released on 1986-12-31 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume on enzootic bovine leukosis (EBL) and bovine leukemia virus (BLV) is the second in our series "Developments in Veterinary Virology". Each book in this series is devoted to a major virus disease of agricultural significance. The chapters in each volume are planned to supply information on a range of subjects from pathogenesis of the causative virus to vaccination, eradication, and rules regarding disease control. The present volume on enzootic bovine leukosis and bovine leukemia virus updates the reader on the disease and its causative agent and includes the nucleotide sequence of the BLV genome as well as data on its integration into the DNA of the tumor cell. Insights into diagnosis, veterinary legislation, and the economic aspects of EBL are also provided. Intense research conducted on EBL and BLV during the course of a decade is presented in a most concise and in-depth manner, so as to provide the reader with a comprehensive overview of this economically important disease of cattle. I wish to thank the editors, A. Burny and M. Mammerickx, as well as all the authors, for making this excellent book available at a stage when the knowledge on bovine leukemia virus will also contribute to our understanding of the virus causing human AIDS.

Download or read book Proceedings of Bovine Leukosis Symposium May 22 23 1979 at the University of Maryland College Park Md written by and published by . This book was released on 1979 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rebhun s Diseases of Dairy Cattle E Book written by Thomas J. Divers and published by Elsevier Health Sciences. This book was released on 2007-10-25 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: REBHUN'S DISEASES OF DAIRY CATTLE, 2nd Edition is your all-in-one guide to bovine disease management. With thorough, up-to-date coverage of differential diagnosis methods, surgical and therapeutic treatment options, and prevention strategies, it provides vital information for battling bovine diseases in both dairy and non-dairy cattle. The book is organized by body system for quick, convenient reference, and this new edition meets the growing need for management of both diseases of individual cows and problems affecting whole herds. - Individual case presentations provide a valuable tool for differential diagnosis. - Practical overviews for procedures such as blood transfusion, abdominal paracentesis, and ECG give you reliable support for some of the most common procedures in bovine care. - Body systems organization makes diagnosis easier and more effective by isolating system-specific diseases and conditions. - Full-color design and over 200 new photographs depict disease processes in realistic clarity and ensure the most accurate diagnosis and treatment. - Emphasis on herd health addresses the dairy industry's increased concern over population medicine. - Expanded coverage of lameness highlights key problem areas in bovine feet. - Revised drug usage recommendations and legal considerations present the most current information in these critical areas to help you prevent dangerous or costly errors. - Additional public health/safety considerations identify diseases that pose a substantial public threat and detail special measures for related care of dairy cattle. - New, innovative DVD features real-time videos of neurologic case studies, ultrasound and endoscopy procedures, and imaging techniques that familiarize you with the latest technological equipment and protocols. - Features coverage of the latest treatment innovations including antibiotic residue testing, care of individual metabolic disease, troubleshooting, and much more.

Download or read book Current Therapy in Large Animal Theriogenology E Book written by Robert S. Youngquist and published by Elsevier Health Sciences. This book was released on 2006-11-23 with total page 1088 pages. Available in PDF, EPUB and Kindle. Book excerpt: An essential resource for both students and practitioners, this comprehensive text provides practical, up-to-date information about normal reproduction and reproductive disorders in horses, cattle, small ruminants, swine, llamas, and other livestock. Featuring contributions from experts in the field, each section is devoted to a different large animal species and begins with a review of the clinically relevant aspects of the reproductive anatomy and physiology of both males and females. Key topics include the evaluation of breeding soundness, pregnancy diagnosis, diagnosis and treatment of infertility, abortion, obstetrics, surgery of the reproductive tract, care of neonates, and the latest reproductive technology. Includes coverage of all large animal species. All sections provide a review of clinically pertinent reproductive physiology and anatomy of males and females of each species. Complete coverage of the most current reproductive technology, including embryo transfer, estrous synchronization, and artificial insemination. A new section on alternative farming that addresses reproduction in bison, elk, and deer. New to the equine section: stallion management, infertility, and breeding soundness evaluation. New to the bovine section: estrous cycle synchronization, reproductive biotechnology, ultrasonographic determination of fetal gender, heifer development, and diagnosis of abortion. New to the porcine section: artificial insemination, boar/stud management, diseases of postpartum period, and infectious disease control. New to the llama section: infectious disease and nutrition.

Download or read book The Geographical Distribution of Animal Viral Diseases written by Stewart Hal and published by Elsevier. This book was released on 2012-12-02 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Geographical Distribution of Animal Viral Diseases attempts to shed some light on the global distribution of 110 different viral diseases, mainly of livestock and companion animals. The world literature was screened for 110 different viruses, and maps were prepared. These maps delineate the global distribution of pathogenic viruses based on authenticated reports from a variety of reliable sources. Four viruses were categorized as affecting more than one species to a significant degree (astrovirus, rabies, rotaviruses, and Rift Valley fever). The largest number of maps involved viruses that affect humans. Of the 28 viruses a large number were from the California encephalitis group. Ten of the 28 viruses were reported only in the Eastern Hemisphere, 14 only in the Western Hemisphere, and four were worldwide. Birds were the next most frequently affected group with the 15 viruses, followed by pigs with 14 viruses. Overall the vector-borne viruses appear to have much sharper and clear-cut geographical boundaries than the others.

Download or read book Investigation of Genetic Responses to Bovine Leukemia Virus Infection in Beef and Dairy Cattle written by Ciarra LaHuis and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The USDA estimated 78% of US beef operations and 89% of US dairy operations are seropositive for Bovine Leukemia Virus (BLV). Cattle infected with BLV may suffer reduced immune function and productivity. Animals with advanced BLV infections may develop lymphoma, leading to carcass condemnation at slaughter. Research has revealed growing evidence of host genetic markers associated with BLV infection. While research on BLV in beef cattle is limited, BLV research in dairy cattle is plentiful. In dairy cattle, evidence of an association between the Bovine Leukocyte Antigen (BoLA)-DRB3 gene locus and proviral load (PVL) has been reported. However, these associations have not been explored in beef cattle. Chapter 1 investigates associations between BoLA-DRB3 alleles and BLV PVL in upper Midwest beef cattle populations (n=157). Associations between BLV PVL and BoLA-DRB3 alleles was determined. Alleles DRB3*033:01 and DRB3*002:01 were found to be associated with lower PVL and DRB3*026:01 with higher PVL. Chapter 2 explores epigenetic relationships between dam and her calf. Epigenetics can be studied through microRNAs (miRNA), a small noncoding RNA species involved in post-transcriptional gene regulation. Variations in maternal environment have long been associated with fetal development and health. The study will measure differential expression of circulating miRNAs in calves born to BLV infected dams (n=24). The study found four miRNAs in 14-day old calves born to BLV infected dams. Literature indicates the miRNAs are associated with immunological response, skeletal muscle development, and cardiac development. The presented thesis provides some of the first insights of allelic and epigenetic regulations associated with BLV infections in cattle.

Download or read book Farm Animal Surgery E Book written by Susan L. Fubini and published by Elsevier Health Sciences. This book was released on 2016-03-01 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: **Selected for Doody's Core Titles® 2024 in Veterinary Medicine** Master the surgical techniques needed to treat large animals! A comprehensive resource, Farm Animal Surgery, 2nd Edition provides clear, step-by-step guidelines to performing common, field-tested surgical procedures. Coverage includes key information such as patient examination and preparation, diagnostic imaging, surgical procedures by body system, anesthesia concerns, fluid therapy, and postoperative management. Written by large animal specialists Susan Fubini and Norm Ducharme, along with a team of expert contributors, this resource is also an invaluable tool in preparing for ACVS or ECVS board exams. - Consistent, logical organization makes it easy to find important information, with each section devoted to a single animal and chapters organized by body system. - Step-by-step guidelines cover bovine, sheep and goat, and swine surgeries by body system. - 775 full-color photographs and anatomic drawings illustrate common disorders, techniques, and equipment for large animal surgery. - Up-to-date information on key surgical techniques keeps you aware of advances in the field and practical knowledge of animal care. - 35 expert contributors provide a diverse, authoritative perspective on the many aspects of large animal surgery. - References are provided for very specialized procedures. - NEW surgical procedures are included for each species — many with illustrated, step-by-step instructions. - NEW coverage of the physical examination includes cow, swine, goats, and sheep, to facilitate more accurate diagnoses of medical or surgical conditions.

Download or read book Trends and Advances in Veterinary Genetics written by Muhammad Abubakar and published by BoD – Books on Demand. This book was released on 2017-03-22 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is very important to understand the recent advances and basic concepts of veterinary genetics to explore the possibilities for control of diseases in animals. They are also significant for enhancing animal production and reproduction. Our book Trends and Advances in Veterinary Genetics provides a concise introduction and details to the aspects of genetics relevant to animal science and production. This is the first edition of the book so it covers the introductory level of topics which are ideal for veterinary students, classroom use, and practitioners who require more guidance with genetics. The book coverage includes the following main sections: Biotechnology and Reproductive Genetics, Advances in Embryonic Genetics, Conservation and Basic Genetics, and Veterinary Genetics and Future. Each book section comprises two chapters from renowned experts from the area and gives readers a unique opportunity to explore the topic.

Download or read book Alteration in Lymphocyte Subpopulations in Bovine Leukosis Virus infected Cattle written by Bernadette Clare Taylor and published by . This book was released on 1991 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Genetic Analysis of Leukosis Incidence in the US Holstein and Jersey Dairy Populations written by and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bovine leukemia virus (BLV) is an oncogenic retrovirus that causes bovine leukosis (BL), a multicentric cancer of B lymphocytes. The BLV affects B lymphocytes in cattle and sheep. Bovine leukemia, lymphosarcoma, and malignant lymphoma are also names given to BL. BLV is an oncogenic that infects approximately 96% of all dairy herds in the US. Among dairy and beef operations surveyed in mid-1990, 89% and 38%, respectively, had BLV present in their herds. In 75% of the positive US dairy herds, at least 25% of the animals were BLV-positive. However, 10.3% of the animals tested in beef cattle were seropositive. Infection with BLV is endemic in US dairy herds, with at least 50% and usually more than 70% of animals within those herds having antibodies to the virus. Continuous scores and binary milk ELISA results for 13,217 Holstein cows from 114 dairy herds across 16 US states and 642 Jersey cows from eight dairy herds were considered. The objectives of this study were to estimate: 1) the heritability of BL incidence in Holstein and Jersey populations, 2) the genetic merit of sires for leukosis susceptibility in dairy cattle, 3) the genetic correlation of BL incidence with milk yield and SCS, and 4) to determine potential genomic regions and gene pathways that might be associated with BL incidence. In summary, this study presented the first, comprehensive genetic study of BL incidence in commercial dairy herds in the US. Estimates of heritability obtained with the two approaches were approximately 8% for both breeds. Genetic correlations among BL, MY and SCS obtained from the linear model were moderate, and higher than those from the threshold model. Estimated SNP effects obtained from the two models indicated some genomic regions that might be associated with BL incidence, such as in chromosomes 1, 14, 16 and 17. Although many additional studies are still necessary to better understand BLV infection and BL, the results found so far indicate an important genetic component contributing to BL incidence, which could be potentially explored to attenuate the economic losses and public health concerns caused by the BL.

Download or read book Emerging and Re emerging Infectious Diseases of Livestock written by Jagadeesh Bayry and published by Springer. This book was released on 2017-02-07 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides comprehensive knowledge on diseases in livestock that are caused by viruses, parasites and bacteria. Emerging and re-emerging pathogens are presented in detail for various animal groups and in-depth insights into pathogenesis and epidemiology will be provided for each of them. In addition, state-of-the-art treatment possibilities, control measures as well as vaccination strategies are discussed. The recent years have witnessed a sharp increase in the number of emerging and re-emerging infectious diseases of livestock and many of these, including Influenza, Corona and Hanta are of public health importance. The reasons for this development are manifold:changes in the climate, life cycle of vectors and increased global travel. Also, due to extensive deforestation, livestock are increasingly coming in direct contact with wild animals that are reservoirs of many emerging pathogens. Recent progress in diagnosis and management of emerging infectious diseases are also topic of this book.

Download or read book Bovine Medicine written by Peter Cockcroft and published by John Wiley & Sons. This book was released on 2015-06-02 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly updated to reflect recent changes in the industry, Bovine Medicine, 3rd Edition, offers practicing large animal veterinarians and veterinary students a comprehensive reference to core aspects of contemporary cattle health and husbandry. New edition of a classic text, featuring thoroughly rewritten text, with coverage shifted to the core aspects of everyday cattle practice Includes new focus on both applied skills and application of knowledge, along with many more full-colour illustrations than in previous editions Represents a toolkit of skills that will support the delivery of contemporary cattle practice Presents a seamless integration of information on husbandry, nutrition, and disease Written by a wide range of experts from around the world