Using a system dynamics framework to assess disease risks of pig value chains in Vietnam

In Vietnam, there are more than 4 million households producing pigs and pork. This accounts for 57% of quantity of meat consumed. One of the most critical constraints to pig production is the presence of animal disease. Pig disease outbreaks are a regular occurrence in various parts of the country, with the industry affected by diseases such as foot and mouth disease, porcine reproductive and respiratory syndrome, classical swine fever, porcine high fever disease, and swine influenza. In addition, food safety issues related to pig diseases and pork-borne diseases have also increasingly become more important concerns for consumers. Recent studies have shown significant changes in consumption behaviour in response to disease outbreaks. For instance, at least half of urban consumers stop consuming pork in times of pig disease epidemics and/or shift consumption to other meat substitutes such as poultry or fish. Disease risks thus have both public health and livelihoods impacts that are important to understand for appropriate policy and practice response. A proposed methodology for investigating disease risks uses a system dynamics analysis framework. System dynamics models are particularly relevant in the study of livestock systems, as they capture the diverse actors and feedbacks present in value chains and their interface with disease risk and behaviour. A system dynamics model is developed that will describe different scenarios of disease risks and the consequences of different interventions to mitigate these risks. Data from a sample of 1000 farmers and value chain actors including all actors in the pig value chain in Vietnam was collected with support from an ACIAR-funded project on Reducing Disease Risks and Improving Food Safety in Smallholder Pig Value Chains in Vietnam. We propose to test the hypotheses that disease risk is affected by type of production system, feeding system and types of feed uses, access to inputs and services, and selected socio-demographic variables associated with farmers and location

Market-based approaches to food safety and animal health interventions: Lessons from smallholder pig value chains in Vietnam

Food safety and animal health issues are increasingly important constraints to smallholder pig production in Viet Nam. Recent studies have highlighted the significant prevalence of animal disease and food‐borne pathogens inherent within the Vietnamese pig sector. These in turn have important negative livelihoods effects on smallholder pig producers and other value chain actors, as well as important public health impacts. An important research gap is in identifying ex‐ante appropriate market‐based policy responses that take into account the tradeoffs between improved animal health and food safety outcomes and their associated costs for different value chain actors as a means of developing chain‐level solutions for their control. In this paper, we constructed a system dynamics model of the pig value chain that combines a detailed model of herd production and marketing with modules on short‐ and long‐term investment in pig capacity, and decisions by value chain actors to adopt different innovations. The model further highlights the feedbacks between different actors in the chain to identify both the potential entry points for upgrading food safety and animal health as well as potential areas of tension within the chain that may undermine uptake. Model results demonstrate that interventions at nodal levels (e.g. only at farm or slaughterhouse level) are less cost‐effective and sustainable than those that jointly enhance incentives for control across the value chain, as weak links downstream undermine the ability of producers to sustain good health practices

Exposure to Maternal Diabetes Induces Salt-Sensitive Hypertension and Impairs Renal Function in Adult Rat Offspring

OBJECTIVE—Epidemiological and experimental studies have led to the hypothesis of fetal origin of adult diseases, suggesting that some adult diseases might be determined before birth by altered fetal development. We have previously demonstrated in the rat that in utero exposure to maternal diabetes impairs renal development leading to a reduction in nephron number. Little is known on the long-term consequences of in utero exposure to maternal diabetes. The aim of the study was to assess, in the rat, long-term effects of in utero exposure to maternal diabetes on blood pressure and renal function in adulthood

Household pork consumption behaviour in Vietnam: Implications for pro-smallholder pig value chain upgrading

Pork represents more than 70% of meat consumption in Vietnam, and pig production provides livelihood for more than 4 million small farmers in the country. Understanding pork consumption behaviour is thus important for upgrading the pig value chains in Vietnam. The study is conducted with 416 households in Hung Yen and Nghe An provinces. The results confirm that pork is the most widely eaten animal source food in Vietnam (about 24.7 kg per capita and year), consumed by more than 95% of the population of different ages and gender. A household spends about USD 30 monthly for pork, accounting for 13% of total food expenditure. Meanwhile, other types of meat appear to be weak substitutes to pork. While consumers select market outlets for pork based on cleanliness, trust in sources, and the absence of disease in pork sold, 99% of them still buy meat in traditional, wet markets. This, coupled with the fact that meat quality is not traceable in the value chain and only 3% of respondents trust in their regular meat supply, implies that the pig value chain, especially the formal/ modern retailing sector in Vietnam, has not yet gained consumer trust. Given saturated pork demand with more than 95% of respondents planning to sustain or decrease their pork consumption, it’s unlikely that pork consumption behaviour will significantly change for the majority of Vietnamese consumers. Several potential implications are drawn for upgrading the pig value chains: (i) Organizing small farms into groups applying good practices that allow meat to be traceable and certified by trusted institutions; (ii) Developing a quality assurance system that can be feasibly established under smallholder conditions, and complies with minimum quality and safety standards tailored to Vietnam’s context, (iii) Strengthening capacity to collect appropriate market information to provide pig producers, particularly smallholders, reliable meat demand and supply forecast to better serve their target consumers; and (iv) Improving cost and quality competitiveness in pig value chains. These are important considerations especially when Vietnam becomes deeply integrated into the global and regional markets when the Trans-Pacific Strategic Economic Partnership Agreement is officially put into practice

The XIIIth Banff Conference on Allograft Pathology: The Banff 2015 Heart Meeting Report: Improving Antibody-Mediated Rejection Diagnostics: Strengths, Unmet Needs, and Future Directions.

The 13th Banff Conference on Allograft Pathology was held in Vancouver, British Columbia, Canada from October 5 to 10, 2015. The cardiac session was devoted to current diagnostic issues in heart transplantation with a focus on antibody-mediated rejection (AMR) and small vessel arteriopathy. Specific topics included the strengths and limitations of the current rejection grading system, the central role of microvascular injury in AMR and approaches to semiquantitative assessment of histopathologic and immunophenotypic indicators, the role of AMR in the development of cardiac allograft vasculopathy, the important role of serologic antibody detection in the management of transplant recipients, and the potential application of new molecular approaches to the elucidation of the pathophysiology of AMR and potential for improving the current diagnostic system. Herein we summarize the key points from the presentations, the comprehensive, open and wide-ranging multidisciplinary discussion that was generated, and considerations for future endeavors

Mast Cells in Kidney Transplant Biopsies With Borderline T Cell-mediated Rejection and Their Relation to Chronicity

Background. Mast cells are potential contributors to chronic changes in kidney transplants (KTx). Here, the role of mast cells (MCs) in KTx is investigated in patients with minimal inflammatory lesions. Methods. Fourty-seven KTx biopsies (2009-2018) with borderline pathological evidence for T cell-mediated rejection according to the Banff'17 Update were retrospectively included and corresponding clinical data was collected. Immunohistochemistry for tryptase was performed on formalin-fixed paraffin-embedded sections. Cortical MCs were counted and corrected for area (MC/mm²). Interstitial fibrosis was assessed by Sirius Red staining and quantified using digital image analysis (QuPath). Results. Increased MC number was correlated to donor age (spearman's r = 0.35, P = 0.022), deceased donor kidneys (mean difference = 0.74, t [32.5] = 2.21, P = 0.035), and delayed graft function (MD = 0.78, t [33.9] = 2.43, P = 0.020). Increased MC number was also correlated to the amount of interstitial fibrosis (r = 0.42, P = 0.003) but did not correlate with transplant function over time (r = -0.14, P = 0.36). Additionally, transplant survival 2 y post-biopsy was not correlated to MC number (mean difference = -0.02, t [15.36] = -0.06, P = 0.96). Conclusions. MC number in suspicious (borderline) for acute T cell-mediated rejection is correlated to interstitial fibrosis and time post-transplantation, suggesting MCs to be a marker for cumulative burden of tissue injury. There was no association between MCs and transplant function over time or transplant survival 2 y post-biopsy. It remains unclear whether MCs are just a bystander or have pro-inflammatory or anti-inflammatory effects in the KTx with minimal lesions.</p