Relative gut lengths of coral reef butterflyfishes (Pisces: Chaetodontidae)

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Coral Reefs 30 (2011): 1005-1010, doi:10.1007/s00338-011-0791-x.Variation in gut length of closely related animals is known to generally be a good predictor of dietary habits. We examined gut length in 28 species of butterflyfishes (Chaetodontidae), which encompass a wide range of dietary types (planktivores, omnivores, corallivores). We found general dietary patterns to be a good predictor of relative gut length, although we found high variation among groups and covariance with body size. The longest gut lengths are found in species that exclusively feed on the living tissue of corals, while the shortest gut length is found in a planktivorous species. Although we tried to control for phylogeny, corallivory has arisen multiple times in this family, confounding our analyses. The butterflyfishes, a speciose family with a wide range of dietary habits, may nonetheless provide an ideal system for future work studying gut physiology associated with specialisation and foraging behaviours.This project was funded in part by a National Science Foundation (USA) Graduate Research Fellowship to MLB.2012-06-1

Food habits of the farmer damselfish Stegastes nigricans inferred by stomach content, stable isotope, and fatty acid composition analyses

The territorial damselfish, Stegastes nigricans, maintains algal farms by excluding invading herbivores and weeding unpalatable algae from its territories. In Okinawa, Japan, S. nigricans farms are exclusively dominated by Polysiphonia sp., a highly digestible filamentous rhodophyte. This study was aimed at determining the diet of S. nigricans in Okinawa and its dependency on these almost-monoculture algal farms based on stomach content and chemical analyses. Stomach content analyses revealed that all available food items in the algal farms (i. e., algae, benthic animal inhabitants, trapped detritus) were contained in fish stomachs, but amorphous organic matter accounted for 68% of the contents. Therefore, carbon and nitrogen stable isotope ratios and fatty acid (FA) compositions were analyzed to trace items actually assimilated in their bodies. Stable isotope analyses showed that benthic animals were an important food source even for this farmer fish. Two essential fatty acids (EFAs), 20:4n6 and 20:5n3, which are produced only by rhodophytes among available food items, were rich in the muscle tissue of S. nigricans as well as in algal mats and detritus, suggesting that algal mats contribute EFAs to S. nigricans directly and indirectly through the food web. In conclusion, S. nigricans ingested algal mats, detritus, and benthic animals maintained within its farm. Algae and detritus were original sources of EFAs, and benthic animals, which were much more abundant in the farms than in outside territories, provided a nitrogen-rich dietary source for the fish

Changes in sodium levels of processed foods among the International Food and Beverage Association member companies in Australia: 2013-2017

Excess dietary sodium is a modifiable cause of high blood pressure. The World Health Organization has targeted a 30 % reduction in mean population sodium consumption by 2025. In 2008, members of the International Food and Beverage Alliance (IFBA) made commitments to lower sodium content in their products. The aim of this study was to determine recent changes in sodium levels between 2013 and 2017 in foods and beverages produced by companies that are IFBA members (n = 10) and non-IFBA members (n = 6) that were included in the 2018 Global Access to Nutrition Index operating in Australia. Independent Samples t-tests and Mann Whitney U tests were used to test the differences in sodium levels. There was no clear difference in sodium content between 2013 and 2017 detectable for the IFBA members (mean difference 17 mg/100 g, 95 % confidence interval (CI), –82 to +48; p = 0.612; median difference 27 mg/100 g, p = 0.582). For the non-IFBA companies there was a decrease in median sodium content (−30 mg/100 g; P = 0.002) but not mean sodium content (−52 mg/100 g, 95 % CI −106 to +3; p = 0.064). Sodium reduction in IFBA companies appear to have had slow progress in Australia. Stronger implementation and monitoring programs are needed to drive industry action

Nutritional Immunology: A Multi-Dimensional Approach

Nutrition is critical to immune defence and resistance to pathogens, with consequences that affect the health, welfare, and reproductive success of individual organisms [1], [2], and also has profound ecological and evolutionary implications [3]–[5]. In humans, under-nutrition, notably of protein, is a major contributor to morbidity and mortality due to infectious diseases, particularly in the developing world [1]. Likewise, over-nutrition and its associated metabolic disorders may impair immune function, disrupt the relationship with symbiotic and commensal microbiota, and increase susceptibility to infectious disease [6]. Despite the undoubted importance of nutrition to immune defence, the challenge remains to capture the complexity of this relationship. There are three main aspects to this complexity: (i) nutrition is a complex multi-dimensional problem for hosts, pathogens, and commensals; (ii) host immunity is a complex, multi-dimensional trait; and (iii) nutrition and immunity interact via multiple direct and indirect pathways, including involvement of the host's microbiota