Dynamics of Bovine Leukemia Virus Transmission on a California Dairy

Dynamics of Bovine Leukemia Virus Transmission on a California Dairy PDF Author: Marie-Liesse Lassauzet
Publisher:
ISBN:
Category :
Languages : en
Pages : 386

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Dynamics of Bovine Leukemia Virus Transmission on a California Dairy

Dynamics of Bovine Leukemia Virus Transmission on a California Dairy PDF Author: Marie-Liesse Lassauzet
Publisher:
ISBN:
Category :
Languages : en
Pages : 386

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Field Studies on the Control of Bovine Leukemia Virus in Dairy Cows

Field Studies on the Control of Bovine Leukemia Virus in Dairy Cows PDF Author: Vickie J. Ruggiero
Publisher:
ISBN: 9781392118214
Category : Electronic dissertations
Languages : en
Pages : 154

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Bovine leukemia virus (BLV) is an oncogenic deltaretrovirus of cattle that is estimated to infect more than 40% of U.S. dairy cows and cost the dairy industry hundreds of millions of dollars per year. BLV inserts a DNA copy (provirus) into the host genome and can cause leukemia and lymphoma in 1-5% of infected animals, while around 30% develop a non-malignant lymphocytosis, often coupled with high proviral load. BLV infection in dairy cows has also been associated with a number of economically important effects, such as decreased milk production, longevity, and immune function. The primary goal of this dissertation was to develop management protocols that can be implemented on U.S. dairy operations. We also aimed to further characterize in vivo immunologic effects of BLV infection, especially at mucosal junctions, hypothesizing that BLV+ cows would have lower concentrations of IgA antibody. To test the effect of BLV infection on total IgA concentrations, we analyzed the milk, saliva, and serum of BLV+ cows with varying lymphocyte count and proviral load profiles for comparison with BLV- herd mates. We found that BLV+ cows exhibited numerically lower concentrations of IgA in both milk and saliva, but not serum, in comparison to BLV- cows. Although the observed decreases were not statistically significant, the biological effects remain unknown. We also observed that the lowest concentrations of IgA were seen in the milk and saliva of BLV+ cows without lymphocytosis or high PVL, and these differences were trending toward significance. Our data, if confirmed, suggests that BLV may be disruptive to the immunology of mucosal junctions. We developed and implemented three field trials to evaluate management protocols for control of BLV in dairy herds. The first trial investigated the frequently suggested management intervention of improved medical hygiene by changing from shared needles and reproductive sleeves to single-use items. In this field trial, BLV- herd mates were assigned to control (re-use) or intervention (single-use) groups and the incidence risk was calculated semi-annually. Although we saw no difference in the risk of new infections in our study, medical hygiene may still play a role in the transmission of BLV as well as other diseases. This study also identified an increase in incidence risk in the summer exposure period. Meanwhile, our second field trial was a novel intervention which used milk ELISA screening to identify BLV+ cows for further characterization of their lymphocyte count (LC) and proviral load (PVL). In this manner, we identified cows thought to be the most infectious to their susceptible herd mates, and worked with herd managers to create a priority removal plan to consider when culling cows or implementing segregation measures. Overall, the three enrolled herds significantly reduced both BLV prevalence and incidence risk over a 2 to 2.5 year period. In this study, no significant associations with season were observed. Our final field trial aimed to demonstrate that milk ELISA testing could be used in herds with low BLV prevalence in order to identify and remove the few remaining BLV+ animals and achieve eradication of the virus. Two herds that were able to remove all BLV+ adult cows were generally successful, though the young stock (first lactation heifers) were a reservoir for reintroduction. In addition, we observed 5 first lactation heifers in one herd which had previously tested negative on serum ELISA but later tested positive on milk ELISA after entering the milking herd. This agrees with reports of latent BLV infections, and provides further evidence that long-term surveillance and further research on the infection dynamics of BLV are needed.

Epidemiology, Infection Dynamics and Effective Control of Bovine Leukemia Virus Within Dairy Herds of Argentina

Epidemiology, Infection Dynamics and Effective Control of Bovine Leukemia Virus Within Dairy Herds of Argentina PDF Author: Gustavo Enrique Monti
Publisher:
ISBN: 9789085042341
Category :
Languages : en
Pages : 164

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Bovine Leukemia Virus Infection in Young Dairy Animals

Bovine Leukemia Virus Infection in Young Dairy Animals PDF Author: Eunyoung Lee
Publisher:
ISBN:
Category :
Languages : en
Pages : 288

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A Cross-sectional Survey for Antibodies to Bovine Leukemia Virus (BLV) and Suggestions for a Control Program for Prevention of Infection with BLV in a California Dairy Herd with Multiple Cases of Lymphosarcoma AND (with Co-author Langston) A Cross-sectional Study of Milk Production and Reproductive Efficiency in Bovine Leukemia Virus Antibody-positive and Antibody-negative Cattle in Two California Dairy Herds

A Cross-sectional Survey for Antibodies to Bovine Leukemia Virus (BLV) and Suggestions for a Control Program for Prevention of Infection with BLV in a California Dairy Herd with Multiple Cases of Lymphosarcoma AND (with Co-author Langston) A Cross-sectional Study of Milk Production and Reproductive Efficiency in Bovine Leukemia Virus Antibody-positive and Antibody-negative Cattle in Two California Dairy Herds PDF Author: Gabriel Ferdinand
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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A Cross-sectional Study of Milk Production and Reproductive Efficiency in Bovine Leukemia Virus Antibody-positive and Antibody-negative Cattle in Two California Dairy Herds AND (with Co-author Ferdinand) A Cross-sectional Survey for Antibodies to Bovine Leukemia Virus (BLV) and Suggestions for a Control Program for Prevention of Infection with BLV in a California Dairy Herd with Multiple Cases of Lymphosarcoma

A Cross-sectional Study of Milk Production and Reproductive Efficiency in Bovine Leukemia Virus Antibody-positive and Antibody-negative Cattle in Two California Dairy Herds AND (with Co-author Ferdinand) A Cross-sectional Survey for Antibodies to Bovine Leukemia Virus (BLV) and Suggestions for a Control Program for Prevention of Infection with BLV in a California Dairy Herd with Multiple Cases of Lymphosarcoma PDF Author: Althaea Langston
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Milk Production and Reproduction Efficiency in Bovine Leukemia Virus (BLV) Infected and Susceptible Cows in One California Dairy Herd

Milk Production and Reproduction Efficiency in Bovine Leukemia Virus (BLV) Infected and Susceptible Cows in One California Dairy Herd PDF Author: Bachir Fekar
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Enzootic Bovine Leukosis and Bovine Leukemia Virus

Enzootic Bovine Leukosis and Bovine Leukemia Virus PDF Author: A. Burny
Publisher: Springer Science & Business Media
ISBN: 9780898388466
Category : Medical
Languages : en
Pages : 314

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Book Description
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.

Large Animal Internal Medicine - E-Book

Large Animal Internal Medicine - E-Book PDF Author: Bradford P. Smith
Publisher: Elsevier Health Sciences
ISBN: 032355444X
Category : Medical
Languages : en
Pages : 2279

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Book Description
**Selected for Doody’s Core Titles® 2024 with "Essential Purchase" designation in Veterinary Medicine** Utilize a problem-oriented approach to the diagnosis of diseases of horses, cattle, sheep, and goats. Large Animal Internal Medicine, 6th Edition covers the diagnosis and management of disease in both ruminant and equine internal medicine. As the first veterinary internal medicine text to use a problem-based approach, it offers discussions of over 150 clinical signs and manifestations, as well as comprehensive coverage of laboratory and diagnostic testing. New to this edition is a versatile online reference platform and coverage of conditions that exist in Europe, Central and South America, Australia, and New Zealand. In addition, thoroughly revised and updated content includes new vaccines and vaccination protocols; the most current laboratories for DNA, genetic, and PCR testing; and colostrum supplements and replacers. It’s everything you need to stay up to date with the latest information on preventing and treating disease in large animals. Discussions of over 150 clinical signs or manifestations of disease provide you with a problem-based approach to diagnosis based on what you’ve observed and what laboratory tests reveal. Causes of Presenting Signs boxes offer quick access to the common, less common, and uncommon diseases associated with manifestations or signs of disease. Causes of Abnormal Laboratory Values boxes highlight the possible interpretations of abnormalities in clinical chemistry, hematology, blood proteins, and clotting tests. More than 200 expert authors contribute information in their areas of expertise for the most current, authoritative information on each topic. NEW! Expert Consult platform provides a versatile digital resource including bonus content, useful references, and videos to meet the needs of practicing equine and large animal veterinarians. NEW! Global conditions of importance are covered, including those previously not discussed, that exist in Europe, Central and South America, Australia, and New Zealand. NEW! Coverage of emerging and re-emerging diseases includes the new pathogen discovery. NEW! Assessment of vaccination status and susceptibility to infection discusses how antibody titers can predict protection for some pathogens. NEW! Description of epigenetics and metagenomics provides detailed coverage of these emerging areas of interest. NEW! Table of zoonoses obtained from large animals includes symptoms and disinfection needs. NEW! Videos demonstrate how to perform ultrasound imaging on an equine and cow abdomen clearly showing where to position the probe, and what depth to use for scans of the kidneys, liver, and bowel. NEW! Coverage of genetic disorders, Hydrocephalus in Fresians and Pulmonary hypoplasia with Anasarca in Dexter cattle help you to treat these disorders. NEW! Extensively updated content clarifies the latest research and clinical findings on the West Nile Virus, therapeutic drug monitoring, muscle disorders, GI microbiota, the genetic basis for Immune-mediated myositis in Quarter Horses, discoveries in antimicrobial drugs, anthelmintic, and vaccines, and more!

Acta Veterinaria Scandinavica

Acta Veterinaria Scandinavica PDF Author:
Publisher:
ISBN:
Category : Veterinary medicine
Languages : en
Pages : 726

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