Revisiting the Economic Impacts of Eimeria and Its Control in European Intensive Broiler Systems With a Recursive Modeling Approach.

Ionophore compounds active against Eimeria species are widely used in intensive broiler systems and have formed the backbone of coccidiosis control for almost 50 years. Producers, however, are under pressure to reduce ionophore use due to consumer concerns over antimicrobial usage in food animals, and antimicrobial resistance. Moreover, current vaccines against Eimeria are commonly considered to be less cost-effective in intensive broiler systems, especially in Europe where attenuated live vaccines are used. An economic assessment of the impact of Eimeria and the disease coccidiosis, including the cost implications of different efficacies of control, is therefore timely to provide evidence for industry and policy development. A mechanistic model of broiler production under varying infection and control states was used to construct a dataset from which system productivity can be measured. Coccidiosis impact increased rapidly as control efficacy decreased. In the total absence of control, median impact was found to maximize at between €2.55 and €2.97 in lost production per meter squared of broiler house over a 33 day growing period. Coccidiosis remains a major risk to intensive broiler systems and the model developed allows investigation of issues related to coccidiosis control, antimicrobial use and the development of antimicrobial resistance.

Providing information about triclabendazole resistance status influences farmers to change liver fluke control practices.

BACKGROUND: Reports of disease and production losses associated with Fasciola hepatica, the common liver fluke, have increased in recent years. Resistance to triclabendazole, one of the principal veterinary medicines used to prevent losses, has been reported and is now considered widespread in fluke endemic regions of the UK. METHODS: Thirteen farmers participated in a trial in 2013 and the triclabendazole resistance status was obtained for each farm. Based on these results, a knowledge exchange programme on fluke control was delivered to nearly 100 farmers in the region. In this follow-up study, 11 farmers involved in the original trial, participated in semistructured in-depth qualitative interviews in July 2017. RESULTS: Overall, participants identified benefits from participating in the 2013 trial, gaining information about triclabendazole resistance on their farms and knowledge about fluke control. The information on their farm's resistance status was a driver for changing their liver fluke control programmes. Factors such as habitual and repetitive behaviours, grazing restrictions due to agri-environmental schemes, economic pressures and climate change were identified that could impede or prevent the adoption of new control strategies. CONCLUSIONS: The study highlights the significance of resistance to triclabendazole and the impact of knowledge exchange programmes in changing liver fluke control practices.

Epithelial changes of congenital intestinal obstruction in a rat model.

INTRODUCTION: Intestinal atresia is a rare congenital affliction that is often associated with severe bacterial infections despite adequate neonatal surgery. Previous studies have focused on enteric nervous system variations. We hypothesized that epithelial systems (ES) may also be involved in the pathophysiology of postnatal disorders. MATERIALS AND METHODS: Global gene expression was measured by transcriptomic analysis in a rat model of induced intestinal atresia. The analyses then focused on genes involved in ES (enterocytes and goblet cells). Rat fetus small intestines at various stages of development (ED15, ED17, ED19, and ED21, n = 22), were used as non-operated controls and compared to the upper and lower segments of rat fetus small intestines with an induced atresia (n = 14; ligature at ED18). The pattern of gene expression was then confirmed by histochemistry, electron microscopy, and RT-qPCR. RESULTS: From ED15 to ED21, the expression of several genes exhibited a physiological increase of ES markers, with a significant increase at the end of gestation. The operated embryos exhibited significantly higher variations of gene expression in the proximal segment than in the distal segment in terms of absorption and the epithelial barrier. An increase in goblet cells and markers was observed in the proximal segment compared to the controls. CONCLUSION: Fetal intestinal obstruction accelerates maturation in the proximal segment and disrupts the intestinal wall in the distal segment, with a decrease in the number of mucosal cells. Moreover, the epithelial cells underwent significant changes, supporting the notion that intestinal disorders involve more than the ENS.

Using economic and social data to improve veterinary vaccine development: Learning lessons from human vaccinology.

The drivers of vaccine development are many and varied. They include, for example, recognition of the burden of a vaccine-targeted disease, prioritisation of the multiple problems associated with a disease, consideration of the differing socio-economic situations under which vaccines are used, the influence of advocacy groups, and assessment of the feasibility of large-scale vaccine manufacture and distribution. In the field of human health, data-driven development of vaccines is becoming increasingly common through the availability of reliable information on the Global Burden of Disease (GBD) and stringent evaluations of vaccination programmes utilising empirical data on costing and effectiveness, and standardised cost-effectiveness thresholds. The data generated from such analyses allow policymakers, implementing partners, industries and researchers to make decisions based on the best, and most contextually relevant, available evidence. In this paper, we wish to explore the current use of economic and social data for the development of veterinary vaccines. Through comparison with the development of human vaccines, we will look for opportunities in animal health sciences to better integrate socio-economic data and analyses into the process of veterinary vaccine selection, development, and field implementation. We believe that more robust animal health impact assessments could add value to veterinary vaccine development by improving resource allocation and animal disease management.

Preventative services offered by veterinarians on sheep farms in England and Wales: Opinions and drivers for proactive flock health planning.

Recent independent UK government reports and studies have highlighted the importance, but lack, of flock health services provided by veterinarians. Qualitative interviews were analysed by thematic analysis to construct belief statements to understand veterinarians' opinions on preventative advice and drivers for current services to sheep farmers. A postal questionnaire was sent to 515 sheep practices registered with the Royal College of Veterinary Surgeon (RCVS) in England and Wales in 2012 to gather quantitative data on these belief statements and to gather demographic information and current services provided by the veterinarian. Exploratory factor analysis with heuristic approaches was conducted on the respondents' belief statements to identify common factors of veterinarian beliefs. Three main factors were identified: motivation for proactiveness, perceived capability to offer preventative services and perceived opportunity to deliver these services. A beta regression model was built to identify the factors significantly associated with the time veterinarians spent in an advisory role. The relative proportion of time increased by 10% (1.01-1.19), 16% (1.03-1.30) and 29% (CI: 1.09-1.53) for each unit increase in score for factor 1 motivation, factor 2 capability and factor 3 opportunity respectively, indicating that these latent factors explained time veterinarians spent in an advisory role with sheep clients. There was a significant correlation between these factors suggesting influence of the associated beliefs between factors. This study provides insight into the nature and drivers of veterinarians' current behaviour and beliefs. These results could be further tested in behaviour intervention studies and help in designing efficient strategies aiming at promoting proactive health services offered by veterinarians on sheep farms in England and Wales.

A capture-recapture analysis in a challenging environment: assessing the epidemiological situation of foot-and-mouth disease in Cambodia.

We performed a two-source capture-recapture analysis for estimating the true number of villages that experienced clinical cases of foot-and-mouth disease (FMD) in 2009 in Svay Rieng province, Cambodia, and assessing the completeness of the official case-reporting procedure. As a first source, we used the 2009 official dataset made up of the 15 FMD-infected villages that were reported to the provincial authorities, and enlarged this list by assuming that all the villages located at less than 4 km from one of these villages also experienced clinical cases in 2009. In addition, we created a retrospective detection protocol using participatory tools cross-checked against a serological survey that detected 13 infected villages. The capture-recapture analysis of these two detection sources led us to the conclusion that 315 (CI(95%) 117-514) villages experienced clinical cases of foot-and-mouth disease in Svay Rieng province in 2009, corresponding to a village-level annual prevalence rate of 0.46 (CI(95%) 0.17-0.74). The official reporting rate to provincial authorities could therefore be evaluated at 0.05 (CI(95%) 0.03-0.13). An analysis of the sensitivity of the estimation of the number of cases to the radius used for enlargement of Source 1 was performed, indicating its low influence. This study clearly highlights the highly enzootic situation of Cambodia regarding foot-and-mouth disease and the substantial underreporting of clinically affected villages to veterinary authorities. We propose explanations for this low notification rate, stress the importance of accurate reporting procedures and, finally, discuss the potential of capture-recapture techniques as a tool for the quantitative evaluation of animal disease surveillance systems.