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Dietary Regimes (dietary + regime)
Selected AbstractsBrief communication: Mass spectroscopic characterization of tetracycline in the skeletal remains of an ancient population from Sudanese Nubia 350,550 CEAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Mark L. Nelson Abstract Histological evidence of tetracycline use has been reported in an ancient X-Group population (350,550 CE) from Sudanese Nubia (Bassett et al., 1980). When bone samples were examined by fluorescent microscopy under UV light at 490 Å yellow,green fluorophore deposition bands, similar to those produced by tetracycline, were observed, suggesting significant exposure of the population to the antibiotic. These reports were met skeptically with claims that the fluorescence was the result of postmortem taphonomic infiltration of bacteria and fungi. Herein, we report the acid extraction and mass spectroscopic characterization of the antibiotic tetracycline from these samples. The bone samples were demineralized in anhydrous hydrogen fluoride which dissolved the bone-complexed tetracycline, followed by isolation by solid phase extraction on reverse-phase media. Chemical characterization by high pressure liquid chromatography mass-spectroscopic procedures showed that the retention times and mass spectra of the bone extract were identical to tetracycline when treated similarly. These results indicate that a natural product tetracycline was detectable within the sampled bone and was converted to the acid-stable form, anhydrotetracycline, with a mass + H of 427.1 amu. Our findings show that the bone sampled is labeled by the antibiotic tetracycline, and that the NAX population ingested and were exposed to tetracycline-containing materials in their dietary regime. Am J Phys Anthropol 143:151,154, 2010. © 2010 Wiley-Liss, Inc. [source] Studies on feed digestibilities in captive Asian elephants (Elephas maximus)JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3-4 2003M. Clauss Summary In order to test the suitability of the horse as a nutritional model for elephants, digestibility studies were performed with six captive Asian elephants on six different dietary regimes, using the double marker method with acid detergent lignin as an internal and chromium oxide as an external digestibility marker. Elephants resembled horses in the way dietary supplements and dietary crude fibre content influenced digestibility, in calcium absorption parameters and in faecal volatile fatty acid composition. However, the absolute digestibility coefficients achieved for all nutrients are distinctively lower in elephants. This is because of much faster ingesta passage rates reported for elephants. No answer is given to why elephants do not make use of their high digestive potential theoretically provided by their immense body weight. Differences in volatile fatty acid concentrations between these captive elephants and those reported from elephants from the wild are in accord with a reported high dependence of free-ranging elephants on browse forage. Zusammenfassung Untersuchungen zur Verdaulichkeit von Futtermitteln bei Asiatischen Elefanten (Elephas maximus) Um zu überprüfen, ob das Pferd als ernährungsphysiolgisches Modelltier für Elefanten herangezogen werden kann, wurden Verdaulichkeitsstudien an sechs im Zoo gehaltenen Indischen Elefanten mit sechs verschiedenen Futterrationen durchgeführt. Dabei wurde die Doppelindikatormethode mit Lignin als internem und Chromoxid als externem Marker verwendet. Elefanten ähnelten Pferden hinsichtlich der Art und Weise, wie sich Ergänzungsfuttermittel und der Rohfasergehalt der Ration auf die Verdaulichkeit auswirkten, hinsichtlich der Kalziumabsorption, und hinsichtlich der Zusammensetzung der flüchtigen Fettsäuren im Kot. Die von Elefanten erzielten absoluten Verdaulich-keitswerte sind jedoch für alle Nährstoffe deutlich niedriger als bei Pferden, was auf die schnellere Passage der Ingesta durch den Verdauungstrakt der Elefanten zurückzuführen ist. Die Frage, warum Elefanten ihr großes Potential zu hohen Verdauungleistungen nicht ausnutzen, das ihnen theoretisch aufgrund ihrer immensen Körpermasse gegeben ist, ist noch nicht beantwortet. Unterschiede in den Konzentrationen von flüchtigen Fettsäuren im Kot zwischen diesen Zoo-Elefanten und Elefanten aus freier Wildbahn spiegeln den hohen Laubanteil in der Nahrung freilebender Tiere wieder. [source] VIRULENCE RESPONSE OF A SALMONELLA TYPHIMURIUM HILA:LACZY FUSION STRAIN TO SPENT MEDIA FROM PURE CULTURES OF SELECTED BACTERIA AND POULTRY CECAL MIXED CULTUREJOURNAL OF FOOD SAFETY, Issue 3 2002J.D. NUTT ABSTRACT Virulence gene expression in Salmonella is triggered by a variety of environmental factors including changes in the gastrointestinal environment of birds during different dietary regimes. The objective of this study was to determine if growth of specific microorganisms alters the environmental conditions sufficiently to signal Salmonella Typhimurium virulence response. Spent media was obtained from a Salmonella Typhimurium hilA:lacZY fusion strain, a poultry Salmonella Typhimurium strain, Eschcrichia coli K12, and Lactobacillus caseii Spent media samples were collected after 2, 4, 8 and 24 h of growth in brain heart infusion broth (BHI) and M9 media, ,-galactosidase assays were performed on the samples to determine virulence expression. Virulence response to Salmonella, spent media was 2-fold greater than Lactobacillus spent media at 4, 8 and 24 h growth (P < 0.05). Virulence expression almost doubled when exposed to Salmonella Typhimurium (NONA) spent media compared to mixed culture spent media at 4 h, and Salmonella Typhimurium (NONA) was significantly higher than mixed culture spent media at 24 h (P < 0.05). Based on these results, it appears that growth of similar bacterial species may alter the composition of rich media sufficiently to influence virulence. [source] On the relationship of dental microwear to dental macrowearAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Christopher W. Schmidt Abstract Dental microwear analysts have demonstrated that hard diets leave numerous microscopic pits on occlusal surfaces. The relationship between occlusal pitting and gross macrowear, however, is not well known. The current study seeks to elucidate the relationship between dental microwear and macrowear by determining if microscopically pitted teeth are associated with greater expressions of macrowear. This study examined microwear and macrowear on mandibular second molars from 60 prehistoric adult Native Americans representing three dietary regimes (foraging, mixed economy, and agriculture). Initially, two dental microwear feature variables were studied: percentage of pits and mean scratch width. Standard macrowear scores ranged from 4 to 40. ANOVAs suggested that neither of the microwear variables was affected by age or sex, but age affected macrowear scores. Because of this, the sample had a balanced number of young and old adults (i.e., those below and above skeletal age 35). A Pearson's correlation showed no covariation between scratch width and the percentage of pits. Regression analysis indicated that macrowear was not a function of the percentage of pits. However, a significant positive relationship was found between dental macrowear and scratch width. A post priori test found a significant negative relationship between macrowear and the total number of scratches. It is concluded, then, that wide scratches remove more enamel and dentin than do numerous pits, although both cause dental wear. It is suggested here that the term "abrasive" be used to describe those microwear profiles that lead to heavy macrowear and have relatively wide scratches. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] | ||||||||||