It costs money to improve the welfare of farm animals. For people with animals under their care, there are many factors to consider regarding changes in practice to improve welfare, and the optimal course of action is not always obvious. Decision support systems for animal welfare, such as economic cost–benefit analyses, are lacking. This review attempts to provide clarity around the costs and benefits of improving farm animal welfare, thereby enabling the people with animals under their care to make informed decisions. Many of the costs are obvious. For example, training of stockpeople, reconfiguration of pens, and administration of pain relief can improve welfare, and all incur costs. Other costs are less obvious. For instance, there may be substantial risks to market protection, consumer acceptance, and social licence to farm associated with not ensuring good animal welfare. The benefits of improving farm animal welfare are also difficult to evaluate from a purely economic perspective. Although it is widely recognised that animals with poor welfare are unlikely to produce at optimal levels, there may be benefits of improving animal welfare that extend beyond production gains. These include benefits to the animal, positive effects on the workforce, competitive advantage for businesses, mitigation of risk, and positive social consequences. We summarise these considerations into a decision tool that can assist people with farm animals under their care, and we highlight the need for further empirical evidence to improve decision-making in animal welfare.
The wMel strain of Wolbachia bacteria is known to prevent dengue and Zika virus transmission in the mosquito vector Aedes aegypti. Accordingly, the release of wMel-infected A. aegypti in endemic regions has been recommended by the World Health Organization as a potential strategy for controlling dengue and Zika outbreaks. However, the utility of this approach could be limited if high temperatures in the aquatic habitats where A. aegypti develop are detrimental to Wolbachia. We exposed wMel-infected A. aegypti eggs and larvae to fluctuating daily temperatures of 30–40°C for three, five, or seven days during their development. We found that Wolbachia levels in females emerging from heat treatments were significantly lower than in the controls that had developed at 20–30°C. Notably, seven days of high temperatures starting at the egg stage reduced Wolbachia levels in emerging females to less than 0.1% of the wMel control levels. However, after adult females returned to 20–30°C for 4–7 days, they experienced differing degrees of Wolbachia recovery. Our findings suggest that the spread of Wolbachia in wild A. aegypti populations and any consequent protection from dengue and Zika viruses might be limited in ecosystems that experience periods of extreme heat, but Wolbachia levels recover partially after temperatures return to normal. The proposed arbovirus biocontrol strategy of releasing mosquitoes infected with the wMel strain of Wolbachia bacteria promises to reduce the transmission of dengue and Zika viruses, but its utility in the field may be limited by the local environment. We show that when Aedes aegypti infected with wMel experience high temperatures during egg and larval development, they have lower Wolbachia levels as emerging adults. High temperatures starting at the egg stage and lasting for seven days reduce Wolbachia levels in emerging females to less than 0.1% of control levels. However, partial recovery of Wolbachia occurs by 4–7 days of age. The spread of Wolbachia in wild A. aegypti populations and any resulting impacts on dengue and Zika transmission could be limited by periods of extreme heat, but Wolbachia levels may subsequently recover.
In this review, we discuss animal welfare as a complex and contested issue facing society and outline why collaborative, multi-stakeholder approaches are critical for effective policy development. Using the lens of “wicked problems” and drawing upon governance literature on policy networks, we identify important factors for working with the inherent complexity of animal welfare through the inclusion of various stakeholder perspectives. We present two case studies that illustrate policy network approaches to animal welfare and highlight the value of fostering collaboration among various stakeholder groups from the industry, community, research, and government sectors. We suggest that the influence of stakeholder networks will likely increase in coming years as newer forms of participatory governance become common. By understanding how collaborative stakeholder networks establish participatory governance, productive communication, and collective priorities, leaders in the field of animal welfare can more productively engage with stakeholders and achieve long-lasting improvements in animal welfare.
With malaria control in Latin America firmly established in most countries and a growing number of these countries in the pre-elimination phase, malaria elimination appears feasible. A review of the literature indicates that malaria elimination in this region will be difficult without locally tailored strategies for vector control, which depend on more research on vector ecology, genetics and behavioural responses to environmental changes, such as those caused by land cover alterations, and human population movements. An essential way to bridge the knowledge gap and improve vector control is through risk mapping. Malaria risk maps based on statistical and knowledge-based modelling can elucidate the links between environmental factors and malaria vectors, explain interactions between environmental changes and vector dynamics, and provide a heuristic to demonstrate how the environment shapes malaria transmission. To increase the utility of risk mapping in guiding vector control activities, definitions of malaria risk for mapping purposes must be standardized. The maps must also possess appropriate scale and resolution in order to become essential tools in integrated vector management (IVM), so that planners can target areas in greatest need of control measures. Fully integrating risk mapping into vector control programmes will make interventions more evidence-based, making malaria elimination more attainable.