Assessment of Virally Vectored Autoimmunity as a Biocontrol Strategy for Cane Toads

BACKGROUND: The cane toad, Bufo (Chaunus) marinus, is one of the most notorious vertebrate pests introduced into Australia over the last 200 years and, so far, efforts to identify a naturally occurring B. marinus-specific pathogen for use as a biological control agent have been unsuccessful. We explored an alternative approach that entailed genetically modifying a pathogen with broad host specificity so that it no longer caused disease, but carried a gene to disrupt the cane toad life cycle in a species specific manner. METHODOLOGY/PRINCIPAL FINDINGS: The adult beta globin gene was selected as the model gene for proof of concept of autoimmunity as a biocontrol method for cane toads. A previous report showed injection of bullfrog tadpoles with adult beta globin resulted in an alteration in the form of beta globin expressed in metamorphs as well as reduced survival. In B. marinus we established for the first time that the switch from tadpole to adult globin exists. The effect of injecting B. marinus tadpoles with purified recombinant adult globin protein was then assessed using behavioural (swim speed in tadpoles and jump length in metamorphs), developmental (time to metamorphosis, weight and length at various developmental stages, protein profile of adult globin) and genetic (adult globin mRNA levels) measures. However, we were unable to detect any differences between treated and control animals. Further, globin delivery using Bohle iridovirus, an Australian ranavirus isolate belonging to the Iridovirus family, did not reduce the survival of metamorphs or alter the form of beta globin expressed in metamorphs. CONCLUSIONS/SIGNIFICANCE: While we were able to show for the first time that the switch from tadpole to adult globin does occur in B. marinus, we were not able to induce autoimmunity and disrupt metamorphosis. The short development time of B. marinus tadpoles may preclude this approach

The Nutritional Quality of Food Provision at UK Government-Funded Holiday Clubs: A Cross-Sectional Analysis of Energy and Nutrient Content

A large proportion of children are at risk of food insecurity during school holidays in the UK. The government-funded Holiday Activities and Food (HAF) programme provides free holiday clubs offering at least one healthy meal/day to eligible children and adolescents. This study aims at evaluating the nutritional quality of food provision at HAF holiday clubs, particularly hot/cold and vegetarian/non-vegetarian meals. Menu variants (n = 2759) from 49 HAF holiday clubs were assessed for adherence to School Food Standards (SFS) and their notional compositional quality, which was scored utilising a novel nutrient-based meal quality index. The median adherence to SFS across all available menus was 70% (IQR 59–79%). Overall, hot variants scored statistically higher menu quality scores than cold variants for both 5–11y (92.3 (80.7–102.7) vs. 80.4 (69.3–90.6)) and 11–18y (73.5 (62.5–85.8) vs. 58.9 (50.0–70.7)) criteria. Cold and hot menu variants tended to score differentially for quality sub-components. These findings highlight areas for potential future improvement in HAF holiday club provision with a tendency for food provision to appear less ideal for attendees for those aged 11–18. Ensuring that children from low-income households have access to a healthy diet is crucial to reduce UK health inequalities