Animal Disease Prevention Research Articles

Magnesium content in soil and roughages depending on soil type and forage crops

The aim of this study is to examine the effects of soil type and forage crops on the content of magnesium in soil and roughages, as well as forage quality regarding Mg content for the prevention of animal disease ?tetany?. The trial was carried out on chernozem and humogley under alfalfa and red clover. Samples for determination of Mg content in plant and total Mg content in soil were digested using the apparatus Milestone Ethos 1. The content of Mg was determined using the apparatus ICP-OES Vista Pro-Axial Varian. The average total Mg content in soil of the tested sites was 0.64%. Total Mg content in chernozem was higher than in humogley. A higher total Mg content was in the deeper horizon. A significant positive correlation was found between total Mg content in soil and soil pH as well as the content of CaCO3. The average Mg content in forage crops was 0.28%. A higher Mg content in the dry matter was observed in crops grown on humogley. Mg content was significantly higher in red clover. There was no risk for the occurrence of animal disease ?tetany? regarding Mg content in crops, because the ratio K/(Ca+Mg) was below 2.2, and K and Mg content in the dry matter of crops was below the critical value.

Etiological and pathological analyses of massive mortality in cultured crab Portunus trituberculatus along the coasts of Tianjin and Hebei, China

PDF HTML阅读 XML下载 导出引用 引用提醒 津冀地区养殖三疣梭子蟹大量死亡的病原和病理分析 DOI: 作者: 作者单位: 1. 上海海洋大学 水产与生命学院, 上海 201306;2. 中国水产科学研究院 黄海水产研究所, 青岛海洋科学与技术国家实验室, 海洋渔业科学与食物产出过程功能实验室, 山东 青岛 266071;3. 天津市水生动物疫病预防控制中心, 天津 300221;4. 青岛中仁动物药品公司, 山东 胶州 266300 作者简介: 王印庚(1963-),博士,研究员,主要从事水产动物疾病防控、刺参养殖技术研究.E-mail:wangyg@ysfri.ac.cn;杨洋,共同第一作者 通讯作者: 中图分类号: S941 基金项目: “十二五”国家科技支撑计划课题（2012BAD17B03）；山东省自主创新与成果转化专项（2014ZZCX06205）；山东省海洋经济创新发展区域示范项目——山东省海水养殖重要疾病高效专用药物研发及产业化项目 Etiological and pathological analyses of massive mortality in cultured crab Portunus trituberculatus along the coasts of Tianjin and Hebei, China Author: Affiliation: 1. College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China;2. Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences; Qingdao National Laboratory for Marine Science and Technology, Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao 266071, China;3. Tianjin Aquatic Animal Disease Prevention and Control Center, Tianjin 300221, China;4. Qingdao Zhongren Animal Health Product Company, Jiaozhou 266300, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:2014年7月，津冀沿海地区池塘养殖三疣梭子蟹（）暴发疾病，导致大量死亡。患病梭子蟹有两种不同表现症状：一种症状为停止摄食，空胃、空肠，行动迟缓；肌肉白浊、不透明，最后乳化呈牙膏状；该病死亡率达60%~70%，称之为“肌肉白浊病”。另一种症状为壳软，停止摄食，行动迟缓；肌肉变白浊、水样变化、萎缩；体腔液及组织坏死液化后从组织中大量渗出，不凝固；死亡率可达90%以上，称之为“牛奶病”。通过疾病流行特征、组织病理、病原超微结构等分析，初步判断肌肉白浊病由一种微孢子虫感染而致，虫体大小（1544±250） nm，呈椭球形，极丝圈数8~9圈，具孢壁[厚（130±22） nm]，纤毛（长120~500 nm）、极体[（726±200） nm]、极管、固定盘、质膜、核等结构；牛奶病则是由一种血卵涡鞭虫（sp.）感染而致，虫体大小8~10 μm，卵圆形，体表多皱褶、凸起，由细胞壁、多核、纤毛等组成。两种患病蟹的肌肉组织病变明显不同：患肌肉白浊病的蟹肌纤维断裂、溃散、浆质化，肌束减少并被团状集聚的寄生虫充斥、占据。电镜观察显示肌纤维细胞破碎、融合，出现大量空泡结构；肌纤维细胞的线粒体、内质网等细胞器解体、消失。患牛奶病的蟹肌束间隙变大，大量血卵涡鞭虫或充斥在间隙中或附着在肌纤维上，导致肌纤维断裂、离散解体，甚至溶解性坏死，组织呈水样变化。电镜观察也证实这两种寄生虫可同时感染三疣梭子蟹个体的同一组织；当肌纤维细胞破碎融合后，两种寄生虫均能寄生在融合后的胞浆中。从发病史来看，肌肉白浊病和牛奶病的发生有蔓延趋势，死亡率趋向更高，已逐步成为三疣梭子蟹养殖的重要疾病。 Abstract:In July 2014, the widely cultured pond crab (commonly called Chinese swimming crab) had a disease outbreak along the coasts of Tianjin and Hebei provinces, China, resulting in massive mortalities. Symptoms of two different illnesses appeared in the crabs. One was white muscle disease (WMD), with its symptoms being anorexia, slowed movement, and the muscles turning opaque white and finally emulsifying into a toothpaste-like consistency. Mortality among the crabs displaying WMD was 60%-70%. The other was milky disease (MD), which displayed as a softened carapace, cessation of feeding, slowed movement, and the muscles similarly turning opaque white but then becoming watery (‘milky') and finally shrinking; the coelomic fluid and the deteriorated tissue leaked from the body and had not coagulated. Mortality among the crabs displaying MD exceeded 90%. According to the characteristics of the epidemic, and histopathological and ultrastructural analyses, the supposed cause of WMD was infection with a microsporidian. The parasite was ellipsoid, measured (1544±250) nm, and had the following structure: pole filament (8 or 9 laps), spore wall [thickness (130±22) nm], cilium (length 120-500 nm), polaroplast [(726±200) nm], pole tube, anchoring disk, plasma membrane and nucleus. The MD outbreak was caused by sp., a monad, sized 8-10 μm, with an oval shape, and wrinkled and raised surface; its basic structure was a cell wall, multiple nuclei, cilium and other structures. Histopathological examination showed that the two kinds of diseased crabs had significantly different muscle lesions. The crabs associated with WMD had many microsporidia adhering to their muscle fibers, causing the fibers to break, collapse and necrosis, finally reducing them to muscle bundles. SEM observations showed that the muscle cells became fused and acquired a large number of vacuoles, while the mitochondria and endoplasmic reticulum disintegrated and disappeared. In comparison, the gap in the muscle bundles was bigger in cases of MD, in which numerous parasites occupied or adhered to the muscle fibers, resulting in the fibers rupture, disintegration, and resolvable necrosis. Electron microscopy also confirmed that the two different parasites could infect the same tissue in the same crab, and both parasites could enter the disintegrated cytoplasm after muscle cell fusion. Since the initial epidemic of these diseases, other occurrences of WMD and MD have tended to cause a higher level of mortality, causing concern as significant diseases currently effecting the crab-farming industry. 参考文献 相似文献 引证文献

THE STUDY OF IMMUNOGENIC ACTIVITY OF ANAEROBIC INFECTION’S EXPERIMENTAL VACCINE CAUSED BY CLOSTRIDIUM SORDELLII OF CATTLE

The article presents main results of study of the immunogenic activity of a vaccine for prevention of disease caused by Clostridium sordellii. Obtained promising data that will help in the future to effectively address the specific prevention of animal diseases.

Bacterial bile salt hydrolase: an intestinal microbiome target for enhanced animal health.

To effectively mitigate antimicrobial resistance in the agricultural ecosystem, there is an increasing pressure to reduce and eliminate the use of in-feed antibiotics for growth promotion and disease prevention in food animals. However, limiting antibiotic use could compromise animal production efficiency and health. Thus, there is an urgent need to develop effective alternatives to antibiotic growth promoters (AGPs). Increasing evidence has shown that the growth-promoting effect of AGPs was highly correlated with the reduced activity of bile salt hydrolase (BSH), an intestinal bacterial enzyme that has a negative impact on host fat digestion and energy harvest; consistent with this finding, the population of Lactobacillus species, the major intestinal BSH-producer, was significantly reduced in response to AGP use. Thus, BSH is a key mechanistic microbiome target for developing novel alternatives to AGPs. Despite recent significant progress in the characterization of diverse BSH enzymes, research on BSH is still in its infancy. This review is focused on the function of BSH and its significant impacts on host physiology in human beings, laboratory animals and food animals. The gaps in BSH-based translational microbiome research for enhanced animal health are also identified and discussed.

Biosecurity and the management of emergency animal disease among commercial beef producers in New South Wales and Queensland (Australia)

Australia places great importance on the prevention and management of emergency animal diseases (EAD), with strict quarantine measures offshore and at the border. Livestock producers are crucial for disease control onshore; however, limited information is available on commercial livestock producers’ practices in relation to the management of disease risks. The aims of this paper are to investigate how commercial beef producers in Australia’s Northern and Southern beef zones manage EADs and to identify drivers for effective biosecurity and EAD prevention. This paper forms part of a broader mixed methods research project involving an analysis of literature and current policies, qualitative semi-structured interviews with government and industry stakeholders and a cross-sectional study among beef producers. The cross-sectional study used a postal survey (n=182) and face-to-face interviews (n=34) to gather data on beef producers’ knowledge and practices on biosecurity and EADs and their communication networks. Findings indicate that producers are uncertain about the roles and responsibilities of stakeholders involved in biosecurity and EAD management. This uncertainty may create confusion about EAD management and impact upon producers’ willingness to report animal disease, with over 20% reporting the last veterinary contact more than five years ago and an additional 8.5% who had never contacted a veterinarian. Producers had a generally high awareness of the key sources of animal disease risk and they prioritise herd health planning as part of their everyday practices. Over 40% of producers had limited knowledge of the meaning of EAD; and EAD and biosecurity planning was given a low priority, primarily due to the perceived limited likelihood of an EAD event in Australia and the belief that EAD prevention is primarily the role of government. Only a moderate implementation of biosecurity practices, such as isolating incoming animals, having a single property entry point or keeping visitors’ records was reported. If faced with an unusual disease event, most producers would contact their private or government veterinarian; however, in some instances most would also treat themselves and over a third would do nothing. Findings from this study suggest that there is a need for better coordination between stakeholders to encourage a shared biosecurity and EAD understanding and to communicate a consistent message to all stakeholders including producers. Further, there is a need for improving producer awareness of the importance of EAD prevention and biosecurity practices as well as the stakeholders’ roles within the broader animal health system.

Salmonella enterica: a review or the trilogy agent, host and environment and its importance in Chile

Salmonella enterica is a major foodborne pathogen worldwide, being the main cause of outbreaks by food consumption in Chile. Despite all efforts deployed for control and prevention, the high incidence in people still persists, with several factors that could be influencing the epidemiological behavior of this infection. The objective of this review is to identify these factors belonging to the biological agent, the human host and the environment, which probably have a greater importance in Chile. Thus, priority areas for research of S. enterica are inferred, which hopefully will help to understand its spread in nature and its success as a wide host range pathogen. In the future, increased understanding of these determinants will facilitate the implementation of biosecurity and surveillance strategies for the prevention of disease in people and animals.

The use of bacteriophages as One-Health approach to reduce multidrug-resistant bacteria

Multidrug-resistant bacteria are increasingly present in humans, animals and the environment. They pose a serious health risk, especially for hospitalized patients. Policymakers, scientists and industry are called to intensify innovation and research for developing new vaccines, diagnostics and infection treatment options. However, very few new antibacterial drugs have been developed in the last decade and several experts already fear that the supply of new antimicrobial agents will one day dry up. Bacteriophages are viruses that specifically and exclusively attack bacteria. They can be isolated from all environments where their host bacteria exist and can be used for decontamination in all stages of food production, for clinical therapy and for prevention of animal disease in livestock. They can thus help us in terms of a One-Health strategy aiming at reducing the selective pressure for resistant bacteria due to reduced release of antibiotics into the environment. Bacteriophages can also help us to treat human and animal infections caused by multidrug-resistant bacteria.

Pantoea agglomerans: a mysterious bacterium of evil and good. Part IV. Beneficial effects.

Pantoea agglomerans, a gammaproteobacterium of plant origin, possesses many beneficial traits that could be used for the prevention and/or treatment of human and animal diseases, combating plant pathogens, promotion of plant growth and bioremediation of the environment. It produces a number of antibiotics (herbicolin, pantocins, microcin, agglomerins, andrimid, phenazine, among others) which could be used for combating plant, animal and human pathogens or for food preservation. Japanese researchers have demonstrated that the low-molecular-mass lipopolysaccharide of P. agglomerans isolated by them and described as 'Immunopotentiator from Pantoea agglomerans 1 (IP-PA1)' reveals the extremely wide spectrum of healing properties, mainly due to its ability for the maintenance of homeostasis by macrophage activation. IP-PA1 was proved to be effective in the prevention and treatment of a broad range of human and animal disorders, such as tumours, hyperlipidaemia, diabetes, ulcer, various infectious diseases, atopic allergy and stress-induced immunosuppression; it also showed a strong analgesic effect. It is important that most of these effects could be achieved by the safe oral administration of IP-PA1. Taking into account that P. agglomerans occurs commonly as a symbiont of many species of insects, including mosquitoes transmitting the Plasmodium parasites causing malaria, successful attempts were made to apply the strategy of paratransgenesis, in which bacterial symbionts are genetically engineered to express and secrete anti-Plasmodium effector proteins. This strategy shows prospects for a successful eradication of malaria, a deadly disease killing annually over one million people, as well as of other vector-borne diseases of humans, animals and plants. Pantoea agglomerans has been identified as an antagonist of many plant pathogens belonging to bacteria and fungi, as a result of antibiotic production, competition mechanisms or induction of plant resistance. Its use as a biocontrol agent permits the decrease of pesticide doses, being a healthy and environmental-friendly procedure. The application of the preparations of this bacterium efficiently protects the stored pome, stone and citrus fruits against invasion of moulds. P. agglomerans strains associated with both rhizosphere and plant tissues (as endophytes) efficiently promote the growth of many plants, including rice and wheat, which are the staple food for the majority of mankind. The promotion mechanisms are diverse and include fixation of atmospheric nitrogen, production of phytohormones, as well as degradation of phytate and phosphate solubilizing which makes the soil phosphorus available for plants. Accordingly, P. agglomerans is regarded as an ideal candidate for an environmental-friendly bioinoculant replacing chemical fertilizers. It has been documented that the Pantoea strains show biodegradation activity on various chemical pollutants of soil and water, including petroleum hydrocarbons and toxic metals. P. agglomerans prevents the penetration of harmful industrial contaminants into deeper parts of soil by biofilm formation, and has an ability to produce hydrogen from waste. Thus, this bacterium appears as a valuable bioremediator which, in some cases, may be acquired as a cheap form of energy. In conclusion, in spite of the proven pathologic role of P. agglomerans in causing occupational diseases of allergic and/or immunotoxic background and accidental infections, the beneficial traits of this species, and of related species of Pantoea genus, are of great value for potential use in many areas of biotechnology. Hence, any restrictions on the use of these organisms and their products should be declined, providing safety precautions at work with the Pantoea biopreparations are maintained.

Treatment of Wastewater Containing Sulfa Drug by Photo Active Anode (Ti/Ru0.3Ti0.7O2) in Photo-assisted Electrochemical Process

Drug residues are unregulated pollutants and are frequently found in the aquatic environment. Due to their extensive use, presence in the aquatic environment and their potential for impacts on wildlife and humans, it is becoming an important environmental issue. The present study evaluates the photo-assisted electrochemical treatment of sulfamethoxazole (SMX), an antibiotic used in the prevention and treatment of human and animal diseases. The experiments were carried out in a photo illuminated flow cell reactor and the effects of current density and concentration of sodium chloride in the supporting electrolyte were determined. The Drug could be removed completely at all current densities while TOC abatement was appreciable during the process. The process followed pseudo-first order kinetics and values of electrical energy-per-order were dependent on current density and sodium chloride concentration. Different reaction intermediates were separated and identified by liquid chromatography coupled with mass spectrometry (LC-MS), thereby providing an insight into the mechanistic details of the degradation pathway. The photo-assisted electrochemical degradation proceeded through competitive reactions such as chlorination, hydroxylation and substitution on the aromatic ring, while further ring opening gave rise to more simple organic compounds and, ultimately, the mineralization of SMX. The possible degradation route were also proposed and discussed. Figure 1

Biological toxicants of alimentary origin

The purpose of this research was to determine the degree of farm animal feed contamination with pathogenic microflora, microscopic fungi, and mycotoxins. Investigation of 16 types of farm animal feeds (barley, wheat, corn, pea, oat, grain mixture, scalpings, oilcakes, fish meal, meat-and-bone meal, combined feeds for pigs of different ages, combined feeds for poultry and cattle, feed additives, and premixes) from 175 farms of different regions of the Russian Federation in the period from 2006 to 2012 revealed the nature of their contamination with pathogenic microflora, microscopic fungi, and mycotoxins. This article provides methods of animal disease prevention when using feeds containing biological contaminants dangerous for animals’ health.

Applications of Bayesian Phylodynamic Methods in a Recent U.S. Porcine Reproductive and Respiratory Syndrome Virus Outbreak.

Classical phylogenetic methods such as neighbor-joining or maximum likelihood trees, provide limited inferences about the evolution of important pathogens and ignore important evolutionary parameters and uncertainties, which in turn limits decision making related to surveillance, control, and prevention resources. Bayesian phylodynamic models have recently been used to test research hypotheses related to evolution of infectious agents. However, few studies have attempted to model the evolutionary dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) and, to the authors' knowledge, no attempt has been made to use large volumes of routinely collected data, sometimes referred to as big data, in the context of animal disease surveillance. The objective of this study was to explore and discuss the applications of Bayesian phylodynamic methods for modeling the evolution and spread of a notable 1-7-4 RFLP-type PRRSV between 2014 and 2015. A convenience sample of 288 ORF5 sequences was collected from 5 swine production systems in the United States between September 2003 and March 2015. Using coalescence and discrete trait phylodynamic models, we were able to infer population growth and demographic history of the virus, identified the most likely ancestral system (root state posterior probability = 0.95) and revealed significant dispersal routes (Bayes factor > 6) of viral exchange among systems. Results indicate that currently circulating viruses are evolving rapidly, and show a higher level of relative genetic diversity over time, when compared to earlier relatives. Biological soundness of model results is supported by the finding that sow farms were responsible for PRRSV spread within the systems. Such results cannot be obtained by traditional phylogenetic methods, and therefore, our results provide a methodological framework for molecular epidemiological modeling of new PRRSV outbreaks and demonstrate the prospects of phylodynamic models to inform decision-making processes for routine surveillance and, ultimately, to support prevention and control of food animal disease at local and regional scales.

Assessment of practices, capacities and incentives of poultry chain actors in implementation of highly pathogenic avian influenza mitigation measures in Ghana.

The animal health services‐seeking behaviour of animal owners related to prevention and control of animal diseases may influence their decisions as to whether or not to use services provided by the public or private sectors. The specific objective of this paper was to assess the practices, capacities and incentives of actors involved in highly pathogenic avian influenza (HPAI) control to provide information for prevention and control in Ghana. Questionnaires were designed based on specific practices, incentives and capacities associated with each mitigation measure that was being assessed. Two peacetime preventive mitigation measures (biosecurity and reporting) and two outbreak containment measures (culling with compensation and movement control) were selected for evaluation. Supply chain actors were characterised based on baseline information. Tables were generated showing proportions of respondents in the various response categories in Likert‐scale type itemised questionnaire. Mean scores (and their standard deviations) for the various actors with regard to mitigation measures were calculated. Pair‐wise comparisons were done using t‐ratio statistic and significance of differences were determined at a Bonferroni adjusted P‐value of 0.0024. The study found statistically significant differences between certain actors for practices (biosecurity, reporting, culling and compensation and movement controls), incentives (reporting and movement control) and capacities (reporting and movement control). The findings provide lessons to help improve education and messages on HPAI and to help provide technical assistance targeted at specific actors to prevent and control future HPAI H5N1 outbreaks in Ghana.

Establishment of a method to detect sulfonamide residues in chicken meat and eggs by high-performance liquid chromatography

Sulfonamides are a group of antimicrobials used for treatment and prevention of infectious diseases in humans and animals. In veterinary practice, sulfonamides are extensively used due to its broad spectrum of activity and low cost. A multi-residue analysis of seven sulfonamides (sulfadiazine, sulfathiazole, sulfapyridine, sulfamerazine, sulfamethazine, sulfamethizole, and sulfamethoxypyridazine) in chicken and eggs using HPLC- DAD detection method has been proposed. Chicken and egg samples were homogenized and extracted with distilled water:ethyl acetate (1:3, v/v) liquid-liquid extraction. The extracts were defatted with n-heptane and dried under nitrogen flow at 55 °C. The dry residue was dissolved in 500 μL methanol:acetic acid:water mixture with a ratio of 10:4:36 (v/v/v) and 10 μL of the sample was subjected to HPLC determination under the following conditions: column, Luna 5 μ C18; particle size, 5 μm; mobile phase, 17 mM acetic acid: methanol: acetonitrile (83:10:7, v/v/v); flow rate, 1.0 mL/min; and detection, 270 nm. The specificity was evaluated by analyzing 30 different blank samples of chicken and eggs in order to verify the absence of potential interfering compounds. No interfering peaks were found around the retention time of analytes in the matrices under investigation. The linear correlation coefficients (r2) for 50–250 ppb range were above 0.99 for all sulfonamides tested. The mean recoveries for chicken and eggs spiked at 50, 100, and 150 ppb were in the range of 86–108% for all analytes. Repeatability and within laboratory reproducibility of the developed method was determined at 100 ppb and quantified as the relative standard deviation was lower than 15%. The decision limits were between 108 and 116 ppb for all analytes whilst the detection capability of all analytes ranged from 129 to 140 ppb. An inexpensive and simple liquid-liquid extraction with isocratic elution mode for rapid analysis of residues of seven sulfonamides in chicken and egg samples using HPLC-DAD detection was established in this study.

Veterinary drugs in the environment and their toxicity to plants.

Veterinary drugs used for treatment and prevention of diseases in animals represent important source of environmental pollution due to intensive agri- and aquaculture production. The drugs can reach environment through the treatment processes, inappropriate disposal of used containers, unused medicine or livestock feed, and manufacturing processes. Wide scale of veterinary pharmaceuticals e.g. antibiotics, antiparasitic and antifungal drugs, hormones, anti-inflammatory drugs, anaesthetics, sedatives etc. enter the environment and may affect non-target organisms including plants. This review characterizes the commonly used drugs in veterinary practice, outlines their behaviour in the environment and summarizes available information about their toxic effect on plants. Significant influence of many antibiotics and hormones on plant developmental and physiological processes have been proved. However, potential phytotoxicity of other veterinary drugs has been studied rarely, although knowledge of phytotoxicity of veterinary drugs may help predict their influence on biodiversity and improve phytoremediation strategies. Moreover, additional topics such as long term effect of low doses of drugs and their metabolites, behaviour of mixture of veterinary drugs and other chemicals in ecosystems should be more thoroughly investigated to obtain complex information on the impact of veterinary drugs in the environment.

Passive immunization with hyperimmune egg-yolk IgY as prophylaxis and therapy for poultry diseases--A review.

Passive immunization with pathogen-specific egg yolk antibodies (IgY) is emerging as a potential alternative to antibiotics for the treatment and prevention of various human and animal diseases. Laying hens are an excellent source of high-quality polyclonal antibodies, which can be collected noninvasively from egg yolks. The use of IgY offers several advantages in that it is environmentally friendly, nontoxic, and reduces the numbers of animals required for antibody production. This paper reviews the use of IgY antibodies in the treatment and prevention of enteric pathogen infections in poultry. Brief descriptions of the production, structure, and properties of IgY are also presented. Some limitations of the technology and future perspectives are discussed.

Selenium Deficiency Deteriorate the Inflammation of S. aureus Infection via Regulating NF-κB and PPAR-γ in Mammary Gland of Mice.

Selenium (Se) is an essential micronutrient contributing to a strong immune system for the prevention of infections and diseases in humans and animals. Dietary Se regulates the immune status and mediates anti-inflammatory action. Mastitis is an inflammation in the mammary gland typically induced through the major pathogen S. aureus. The aim of the present study was to determine the regulating effect of Se on S. aureus-induced inflammation using a mouse mastitis model. Immunofluorescence staining was used to detect histopathological injury. ELISA was used to detect cytokine expression, while protein and mRNA levels were analyzed through Western blotting and qPCR analysis, respectively. The results showed that Se deficiency increased inflammatory lesions in individuals with S. aureus infection in the mammary gland. The NO levels showed a significant increase in Se-deficient mice with S. aureus mastitis. Se deficiency accelerated the production of pro-inflammatory factors and reduced IL-10 expression. Furthermore, the results of the present study showed that the regulating effect of Se on S. aureus-induced mastitis was associated with the NF-κB pathway. Indeed, Se deficiency suppressed PPAR-γ activity and promoted NF-κB pathway activation. Thus, Se supplementation could improve the effect on PPAR-γ and NF-κB. These results suggest that Se deficiency could aggravate the inflammatory injury resulting from S. aureus-induced mastitis. Moreover, the results of the present study contribute to the development of new prevention or treatment methods for S. aureus-induced mastitis and other infectious diseases.

Survey of farmer knowledge and attitudes to endemic disease management in South Australia, with a focus on bovine viral diarrhoea (bovine pestivirus)

We aimed to establish the attitudes of South Australian cattle farmers towards endemic animal disease prevention and control, with a particular focus on the awareness of and attitudes towards bovine viral diarrhoea (BVD). This cross-sectional postal survey involved mailing a questionnaire to all South Australian cattle owners with 35 or more head of cattle. Worms and lice were the most common animal disease concerns. Less than half of responding farmers were adequately vaccinating their herds against clostridial diseases, but 53.0% stated that they utilised quarantine procedures. Less than 20% of respondents had actively taken part in BVD educational opportunities, or had vaccinated or tested their herd for BVD; less than 20% of respondents were actively involved in any systematic control of Johne's disease. Overall, farmers' actual knowledge of BVD was lower than their perceived understanding, although their interest in BVD and its control was high. Disease prevention measures such as vaccination, quarantine and participation in systematic control schemes were used by a minority of respondents. The results suggest that respondents acknowledge BVD as an important and relevant disease, despite many believing it was not a problem in their herd. Interest in BVD appears to be high and it is likely that an education program would be well received.

Asymmetric Information, Externalities and Incentives in Animal Disease Prevention and Control

AbstractIncentives influence behaviour while an understanding of farmer behaviour facilitates the control and prevention of infectious livestock disease. This paper lays out several perspectives on how information problems and other externalities affect biosecurity incentives. We use the principal–agent framework to examine livestock disease management in the presence of potential moral hazard and adverse selection. Moral hazard may apply to biosecurity decisions while adverse selection may apply to disease reporting. The example of compensation policies illustrates the importance of creating appropriate incentives: compensation must be sufficient to ensure early reporting but not so large as to discourage appropriate levels of biosecurity effort. Other cases of externalities are more diffuse than those modelled using principal–agent analysis, placing emphasis on third‐party effects and coordination problems. Three examples are provided. One concerns free‐riding when facing an endemic disease pool that can be managed by limiting sources and flows. Another regards coordination failure when securing against an exotic disease where farmer efforts complement and communicating actions are important. The last arises from absence of a risk market where an adverse infrastructural support externality could be managed by disease outbreak insurance.

Comparison of sampling procedures and microbiological and non-microbiological parameters to evaluate cleaning and disinfection in broiler houses

Cleaning and disinfection of the broiler stable environment is an essential part of farm hygiene management. Adequate cleaning and disinfection is essential for prevention and control of animal diseases and zoonoses. The goal of this study was to shed light on the dynamics of microbiological and non-microbiological parameters during the successive steps of cleaning and disinfection and to select the most suitable sampling methods and parameters to evaluate cleaning and disinfection in broiler houses. The effectiveness of cleaning and disinfection protocols was measured in six broiler houses on two farms through visual inspection, adenosine triphosphate hygiene monitoring and microbiological analyses. Samples were taken at three time points: 1) before cleaning, 2) after cleaning, and 3) after disinfection. Before cleaning and after disinfection, air samples were taken in addition to agar contact plates and swab samples taken from various sampling points for enumeration of total aerobic flora,Enterococcus spp., andEscherichia coli and the detection ofE. coli andSalmonella. After cleaning, air samples, swab samples, and adenosine triphosphate swabs were taken and a visual score was also assigned for each sampling point. The mean total aerobic flora determined by swab samples decreased from 7.7 ± 1.4 to 5.7 ± 1.2 log CFU/625 cm2 after cleaning and to 4.2 ± 1.6 log CFU/625 cm2 after disinfection. Agar contact plates were used as the standard for evaluating cleaning and disinfection, but in this study they were found to be less suitable than swabs for enumeration. In addition to measuring total aerobic flora,Enterococcus spp. seemed to be a better hygiene indicator to evaluate cleaning and disinfection protocols thanE. coli. All stables wereSalmonella negative, but the detection of its indicator organismE. coli provided additional information for evaluating cleaning and disinfection protocols. Adenosine triphosphate analyses gave additional information about the hygiene level of the different sampling points.

Brucellosis control in northeast China: a long way to go

X. Zhang , Z. Wang , G. Mu , T. Wang d,e a Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun 130062, China b First Institute of Prevention and Treatment on Endemic Diseases of Jilin Province, Baicheng 137000, China c Jilin Provincial Center for Animal Disease Control and Prevention, Changchun 130062, China d Baicheng Normal University, Baicheng 137000, China e Military Veterinary Research Institute of Academy of Military Medical Sciences, Changchun 130122, China