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111.
Important infectious diseases in farm animals, such as pneumonia and enteritis, are thought to be associated with the so-called oxidative stress, i.e. a chemical phenomenon involving an imbalance in the redox status of the individual animal. The specifics of oxidative stress and how it may result in disease or be prevented are complex questions with no simple answers. However, the considerable literature on the subject suggests that many researchers consider oxidative stress-related mechanisms to be important early events in disease development. A particularly intriguing aspect is that, at least theoretically, oxidative stress should be easily prevented with antioxidants yet the use of antioxidants as therapy remains controversial. The present knowledge on oxidative stress in farm animals is the topic of this review. 相似文献
112.
吡喹酮脂质体对实验动物的毒性作用研究 总被引:1,自引:0,他引:1
为探明吡喹酮脂质体对实验动物是否具有毒性作用,分别进行了急性和亚急性毒性试验,肝功能及血常规检查,结果表明,吡喹酮脂质体对小白鼠的半数致死量(LD50)为腹腔注射1865mg/kg,分别以1/20和1/10LD50的剂量隔天给小白鼠腹腔注射,连续试验70d,均无临床病理变化,给供试兔耳静脉注射该制剂10mg/kg,给药后1-5d的肝功能和血液生理生化指标同给药前相比均无显著差异。 相似文献
113.
C. KROSSØY R. WAAGBØ P.-G. FJELLDAL A. WARGELIUS E.-J. LOCK I.E. GRAFF & R. ØRNSRUD 《Aquaculture Nutrition》2009,15(6):638-649
The aim of the present study was to elucidate if increasing levels of added vitamin K in the feed influenced fish growth, health or the incidences of bone deformities in Atlantic salmon ( Salmo salar L.) from onset of start feeding to ∼100 g in freshwater. Duplicate groups of Atlantic salmon fry (∼0.20 g) were fed eight levels (0, 2.5, 5, 7.5, 10, 15, 20 and 50 mg menadione kg−1 ) of the vitamin K derivate menadione nicotinamide bisulphite (MNB) in a regression design for 28 weeks. All fish maintained high growth rates throughout the experiment, and showed no significant differences in specific growth rate, condition factor, whole body proximate analysis, blood coagulation time, vertebra morphology or mechanical properties of vertebrae. We found a dose-response between whole body vitamin K concentration and the dietary MNB supplementation level. Analysis of liver γ-glutamylcarboxylase activity revealed significant dose-dependent differences between groups given the 0, 10 and 50 mg MNB kg−1 diets. In conclusion, Atlantic salmon seems to require low levels of dietary vitamin K, and the amount of vitamin K found naturally in the presently used feed ingredients may be enough to maintain optimal growth, health and bone strength in Atlantic salmon fry from start feeding. 相似文献
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鼠疫是鼠疫耶尔森菌借鼠蚤传播为主的甲类传染病,系广泛流行于野生啮齿类动物间的一种自然疫源性疾病,易感动物主要为啮齿动物,人类一旦感染对其生命健康存在极大的危害。榆林地区虽然目前未发生动物间鼠疫疫情流行,但与榆林地区接壤的内蒙、宁夏等地近年来相继报道出现动物间鼠疫疫情传播情况。本文通过对鼠疫的流行特点和传播途径进行论述,对榆林地区目前面临的形势及风险进行研判,并进一步对本地人间鼠疫防控工作进行深入调查研究,为逐步建立系统性的动物间鼠疫监测工作提供科学依据。 相似文献
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Design standards for experimental and field studies to evaluate diagnostic accuracy of tests for infectious diseases in aquatic animals 下载免费PDF全文
E Laurin K K Thakur I A Gardner P Hick N J G Moody M S J Crane I Ernst 《Journal of fish diseases》2018,41(5):729-749
Design and reporting quality of diagnostic accuracy studies (DAS) are important metrics for assessing utility of tests used in animal and human health. Following standards for designing DAS will assist in appropriate test selection for specific testing purposes and minimize the risk of reporting biased sensitivity and specificity estimates. To examine the benefits of recommending standards, design information from published DAS literature was assessed for 10 finfish, seven mollusc, nine crustacean and two amphibian diseases listed in the 2017 OIE Manual of Diagnostic Tests for Aquatic Animals. Of the 56 DAS identified, 41 were based on field testing, eight on experimental challenge studies and seven on both. Also, we adapted human and terrestrial‐animal standards and guidelines for DAS structure for use in aquatic animal diagnostic research. Through this process, we identified and addressed important metrics for consideration at the design phase: study purpose, targeted disease state, selection of appropriate samples and specimens, laboratory analytical methods, statistical methods and data interpretation. These recommended design standards for DAS are presented as a checklist including risk‐of‐failure points and actions to mitigate bias at each critical step. Adherence to standards when designing DAS will also facilitate future systematic review and meta‐analyses of DAS research literature. 相似文献
119.
Matias Bermann Daniela Lourenco Vivian Breen Rachel Hawken Fernando Brito Lopes Ignacy Misztal 《Journal of animal science》2021,99(4)
The introduction of animals from a different environment or population is a common practice in commercial livestock populations. In this study, we modeled the inclusion of a group of external birds into a local broiler chicken population for the purpose of genomic evaluations. The pedigree was composed of 242,413 birds and genotypes were available for 107,216 birds. A five-trait model that included one growth, two yield, and two efficiency traits was used for the analyses. The strategies to model the introduction of external birds were to include a fixed effect representing the origin of parents and to use unknown parent groups (UPG) or metafounders (MF). Genomic estimated breeding values (GEBV) were obtained with single-step GBLUP using the Algorithm for Proven and Young. Bias, dispersion, and accuracy of GEBV for the validation birds, that is, from the most recent generation, were computed. The bias and dispersion were estimated with the linear regression (LR) method,whereas accuracy was estimated by the LR method and predictive ability. When fixed UPG were fit without estimated inbreeding, the model did not converge. In contrast, models with fixed UPG and estimated inbreeding or random UPG converged and resulted in similar GEBV. The inclusion of an extra fixed effect in the model made the GEBV unbiased and reduced the inflation. Genomic predictions with MF were slightly biased and inflated due to the unbalanced number of observations assigned to each metafounder. When combining local and external populations, the greatest accuracy can be obtained by adding an extra fixed effect to account for the origin of parents plus UPG with estimated inbreeding or random UPG. To estimate the accuracy, the LR method is more consistent among scenarios, whereas the predictive ability greatly depends on the model specification. 相似文献
120.
Paolo Borghetti Roberta Saleri Eugenio Mocchegiani Attilio Corradi Paolo Martelli 《Veterinary immunology and immunopathology》2009,130(3-4):141-162
The Central Nervous (CNS) and Immune Systems (IS) are the two major adaptive systems which respond rapidly to numerous challenges that are able to compromise health. The defensive response strictly linking innate to acquired immunity, works continuously to limit pathogen invasion and damage. The efficiency of the innate response is crucial for survival and for an optimum priming of acquired immunity. During infection, the immune response is modulated by an integrated neuro-immune network which potentiates innate immunity, controls potential harmful effects and also addresses metabolic and nutritional modifications supporting immune function. In the last decade much knowledge has been gained on the molecular signals that orchestrate this integrated adaptive response, with focus on the systemic mediators which have a crucial role in driving and controlling an efficient protective response. These mediators are also able to signal alterations and control pathway dysfunctions which may be involved in the persistence and/or overexpression of inflammation that may lead to tissue damage and to a negative metabolic impact, causing retarded growth.This review aims to describe some important signalling pathways which drive bidirectional communication between the Immune and Nervous Systems during infection. Particular emphasis is placed on pro-inflammatory cytokines, immunomodulator hormones such as Glucocorticoids (GCs), Growth hormone (GH), Insulin-like Growth Factor-1 (IGF-1), and Leptin, as well as nutritional factors such as Zinc (Zn).Finally, the review includes up-to-date information on this neuroimmune cross-talk in domestic animals. Data in domestic animal species are still limited, but there are several exciting areas of research, like the potential interaction pathways between mediators (i.e. cytokine-HPA regulation, IL-6-GCS-Zn, cytokines-GH/IGF-1, IL-6-GH-Leptin and thymus activity) that are or could be promising topics of future research in veterinary medicine. 相似文献