322 research outputs found

    Farm animal health : progress, problems and perspectives

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    Economic Analysis of Johne's Disease Control Strategies in Dairy Herds

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    Infectious diseases play a critical role in determining the profitability of individual farms and maintaining the viability of livestock industries, international trade, and trade policies. Thus, it is critical to analyze the economic consequences of infectious diseases, and the effects of producer strategies to control or eliminate diseases in a cost efficient approach. Also, important is the goal to rally support for the development of public disease control programs. This study examined the long-term feasibility and effectiveness of various producer strategies to prevent and control Johne’s disease in dairy herds, an infectious and incurable disease which has significant economic repercussions for the dairy industry. There are few previous studies available on the economic aspects of Johne’s disease and there remains a knowledge gap with regard to the economics of the disease and the economic justification of the disease controls associated with the biological characteristics of the disease. This study contributes to this body of knowledge. We constructed an optimal control model integrating the biology of animals and disease into an economic framework to estimate the best control method in terms of maximizing an individual farm’s profit and minimizing disease elimination periods. Our results show that any Johne’s disease control method yields a higher net present value compared to no control. Implementing a single control strategy can control the disease, but a combination of control strategies in different categories is the most profitable and effective way to reduce the infection rate in a disease-infected herd. The results of the study are directly applicable to managing this disease on US dairy farms and contribute to controlling a high-priority pathogen in an important industry.Animal disease control, dairy herd model, Johne's disease, optimal control model, paratuberculosis, Agribusiness, Farm Management, Livestock Production/Industries, Research and Development/Tech Change/Emerging Technologies,

    Конституційний статус вітчизняної прокуратури: перспективи подальшого розвитку

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    Статья посвящена современным конституционно-правовым проблемам формирования и развития статуса прокуратуры Украины. В ней проанализировано основные факторы, которые имели влияние на процесс совершенствования организационных и функциональных основ деятельности органов отечественной прокуратуры в нынешних условиях. Особенное внимание уделено значению международных стандартов определения роли прокуратуры в демократическом обществе. Ключевые слова: Конституционная модель, Декларация о государственном суверенитете, Конституция, Генеральный прокурор Украины, институт прокуратуры.The article is devoted the modern constitutional-legal problems of forming and development of status of office of public prosecutor of Ukraine. Basic factors which had an influence on the process of perfection of organizational and functional bases of activity of organs of domestic office of public prosecutor in present terms are analysed in it. The special attention is spared the value of international standards of decision of role of office of public prosecutor in democratic society. Key words: Constitutional model, Declaration about state sovereignty, Constitution, Prosecutor general of Ukraine, institute of office of public prosecutor

    Compartment Model for Controlling Infectious Livestock Disease: Cost-Effective Control Strategies for Johne's Disease In Dairy Herds

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    Replaced with revised version of paper 06/08/11.animal compartment model, dairy cattle disease, Johne’s disease, livestock disease control, Mycobacterium avium subspecies paratuberculosis, Farm Management, Livestock Production/Industries,

    A multispecies model for the transmission and control of mastitis in dairy cows

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    Mastitis in dairy cows is a significant economic and animal welfare issue in the dairy industry. The bacterial pathogens responsible for infection of the mammary gland may be split into two main categories: major and minor pathogens. Infection with major pathogens generally results in clinical illness or strong inflammatory responses and reduced milk yields, whereas minor pathogen infection is usually subclinical. Previous investigations have considered the transmission of these pathogens independently. Experimental evidence has shown cross-protection between species of pathogens. In this study a mathematical model for the coupled transmission of major and minor pathogens along with their interaction via the host was developed in order to consider various methods for controlling the incidence of major pathogen infection. A stability analysis of the model equilibria provides explanations for observed phenomena and previous decoupled modelling results. This multispecies model structure has provided a basis for quantifying the extent of cross-protection between species and assessing possible control strategies against the disease

    Modelling the dynamics of intramammary E. coli infections in dairy cows: understanding mechanisms that distinguish transient from persistent infections

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    The majority of intramammary infections with Escherichia coli in dairy cows result in transient infections with duration of about 10 days or less, although more persistent infections (2 months or longer) have been identified. We apply a mathematical model to explore the role of an intracellular mammary epithelial cell reservoir in the dynamics of infection. We included biological knowledge of the bovine immune response and known characteristics of the bacterial population in both transient and persistent infections. The results indicate that varying the survival duration of the intracellular reservoir reproduces the data for both transient and persistent infections. Survival in an intracellular reservoir is the most likely mechanism that ensures persistence of E. coli infections in mammary glands. Knowledge of the pathogenesis of persistent infections is essential to develop preventive and treatment programmes for these important infections in dairy cows

    Acute systemic loss of Mad2 leads to intestinal atrophy in adult mice

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    Chromosomal instability (CIN) is a hallmark of cancer, leading to aneuploid cells. To study the role that CIN plays in tumor evolution, several mouse models have been engineered over the last 2 decades. These models have unequivocally shown that systemic high-grade CIN is embryonic lethal. We and others have previously shown that embryonic lethality can be circumvented by provoking CIN in a tissue-specific fashion. In this study, we provoke systemic high-grade CIN in adult mice as an alternative to circumvent embryonic lethality. For this, we disrupt the spindle assembly checkpoint (SAC) by alleviating Mad2 or truncating Mps1, both essential genes for SAC functioning, with or without p53 inactivation. We find that disruption of the SAC leads to rapid villous atrophy, atypia and apoptosis of the epithelia of the jejunum and ileum, substantial weight loss, and death within 2-3 weeks after the start of the CIN insult. Despite this severe intestinal phenotype, most other tissues are unaffected, except for minor abnormalities in spleen, presumably due to the lower proliferation rate in these tissues. We conclude that high-grade CIN in vivo in adult mice is most toxic to the high cell turnover intestinal epithelia
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