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The physiology of ticks supports a diverse community of non-pathogenic and pathogenic organisms. This study aims to initially characterize the microbial community present within colony-reared Amblyomma americanum using PCR of the variable region 5 of the 16S rRNA gene followed by semiconductor sequencing and classification of sequence data using the Ribosomal Database Project and MG-RAST analysis tools. Comparison of amplicon library datasets revealed changes in the microbiomes in newly engorged nymphs, newly-molted adults, and aged adults, as well as ticks exposed to different environmental conditions. These preliminary data support the concept that microbe survivorship and diversity are partially dependent upon environmental variables and the sequence of blood feeding, molting, and aging. The maintenance and/or emergence of pathogens in ticks may be dependent in part on temporal changes in the microbial community of the tick microbiome. [ABSTRACT FROM AUTHOR]

Rates of fatty acid biohydrogenation and passage were determined for fat supplements varying in saturation using lactating dairy cows. First-order fractional passage rates were determined by dividing the duodenal flux of fatty acids by their respective ruminal pool sizes. The determination of rates of biohydrogenation required the development of a model to account for the transfer of fatty acids among pools. Ruminally and duodenally cannulated multiparous Holstein cows (n = 8) were used in a replicated 4 x 4 Latin square design with 21-d periods. Treatments were control and a linear substitution of 25 g/kg supplemented fatty acids varying in saturation as follows: saturated (prilled hydrogenated free fatty acids), intermediate mix of saturated and unsaturated (calcium soaps of long-chain fatty acids), and partially unsaturated fatty acids. Passage rates of 16:0, 18:0, and total 18-carbon fatty acids were linearly decreased with increasing unsaturated fatty acids and the trans-18:1 fractional passage rate was quadratically affected with a maximum for the intermediate treatment. Increasing unsaturated fatty acids increased the extent of 18:2 and 18:3 biohydrogenation and decreased the extent of 18:1 and trans-18:1 biohydrogenation. Calcium salts did not protect PUFA from ruminal biohydrogenation despite a mean ruminal pH of 6.0, and unsaturated fatty acids decreased ruminal biohydrogenation of trans-18:1, resulting in increased duodenal flow of these fatty acids. The model allows a mechanistic description of ruminal biohydrogenation and determination of the extent of 18:1 biohydrogenation. [ABSTRACT FROM AUTHOR]

Gluconeogenic capacity may be an important factor regulating dry matter intake (DMI) in lactating dairy cows. To determine whether increased glucose demand affects feed intake and hepatic gene expression, lactating Holstein cows were treated with phlorizin or vehicle (propylene glycol) for 7 d. Multiparous cows (n = 12; 269 ± 65 d in milk, mean ± SD) were randomly assigned to treatment sequence in a crossover design and were adapted to a common diet for 7 d before the beginning of the experiment. Phlorizin injected s.c. at 4 g/d caused glucose excretion in urine at the rate of 474 g/d. Although phlorizin decreased lactose synthesis and milk production (both P < 0.01), DMI and 3.5% fat-corrected milk production were not altered by treatment. A net deficit of 383 g glucose/d in milk and urine for phlorizin (relative to control) was likely replaced partially through increased gluconeogenesis. The molar insulin:glucagon ratio was decreased 17% by phlorizin (P < 0.001) and hepatic phosphoenolpyruvate carboxykinase, glucose-6-phosphatase, and pyruvate carboxylase mRNA abundance increased (all P < 0.05). Late-lactation dairy cows adapted quickly to an increase in peripheral glucose demand; adaptation mechanisms likely included enhanced gluconeogenic capacity, whereas DMI was not altered. [ABSTRACT FROM AUTHOR]

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Two experiments were conducted to evaluate how dose-response effects of intraruminal infusion of propionate on feeding behavior and plasma metabolites are altered by diets differing in fermentability. Twelve ruminally cannulated Holstein cows were used in each experiment. Cows were fed diets containing either steam flaked corn or dry cracked corn (30% of dietary dry matter) in expt. 1, and diets differing in forage-to-concentrate ratio (66:34 vs. 36:64) in expt. 2. For both experiments, the experimental design was a crossover for dietary treatment, and a 6 x 6 Latin square for infusion treatment within a diet for each period. Infusion treatments were mixtures of sodium propionate and sodium acetate, containing propionate at 0, 0.2, 0.4, 0.6, 0.8 and 1.0 as a fraction of total volatile fatty acids infused. Treatment solutions were infused into the rumen continuously for 18 h starting 6 h before feeding at a rate of 23.1 mmol/min. Although propionate production from ruminal fermentation was expected to be different, dietary treatments did not affect dry matter intake (DMI) responses to propionate infusion for either experiment. However, propionate infusion decreased DMI linearly in expt. 1, but did not decrease DMI at lower rates of propionate infusion, which were much more effective at increasing plasma glucose concentration in expt. 2. Propionate had a smaller hypophagic effect at low concentrations of plasma glucose and had a greater hypophagic effect at elevated concentrations of plasma glucose, which could be explained by changes in the metabolism of propionate in the liver. [ABSTRACT FROM AUTHOR]

The dose-response effects of intraruminal infusion of propionate on feeding behavior of lactating dairy cows were evaluated with eight ruminally cannulated Holstein cows past peak lactation. Treatments were mixtures of propionic acid and acetic acid containing propionic acid at eight different concentrations in Experiment 1, and mixtures of sodium propionate and sodium acetate containing sodium propionate at 4 different concentrations in Experiment 2. Experimental designs were an 8 x 8 and duplicated 4 x 4 Latin squares, respectively, for Experiments 1 and 2. Treatment solutions were infused into the rumen continuously for 14 h at a rate of 16.7 and 25 mmol/min, respectively, for Experiments 1 and 2. Infusion started 2 h before feeding and ended 12 h after feeding; feeding behavior was monitored for 12 h after feeding using a computerized data acquisition system. Total metabolizable energy (ME) intake was calculated by adding the energy of infusates to dietary energy intake. In both experiments, as the proportion of propionate of the infusates increased, total ME intake and dry matter intake decreased linearly. As infusion of propionate increased, meal size tended (P < 0.09) to decrease linearly and intermeal interval tended (P < 0.07) to increase linearly in Experiment 1; meal size decreased linearly and number of meal bouts tended (P < 0.08) to decrease linearly in Experiment 2. These observations indicate that the reduction in dietary energy intake from propionate infusion was greater than the energy supplied from infusates, and that propionate plays an important role in feed intake regulation by affecting both satiety and hunger. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to determine interactions between hypophagic effects of propionate and ammonium in lactating dairy cows. Eight ruminally cannulated Holstein cows in mid-lactation were used in a duplicated 4 x 4 Latin square design experiment with a 2 x 2 factorial arrangement of treatments. Factors evaluated were type of volatile fatty acid (VFA; acetate vs. propionate) and type of salt (sodium vs. ammonium). Treatment solutions were infused continuously into the rumen at a rate of 16.7 mmol of VFA salts/min starting 2 h before feeding and ending 12 h after feeding. Hypophagic effects of ammonium were significantly greater for cows infused with propionate (4.3 vs. 12.1 kg/12 h; SEM = 1.3) compared with acetate (13.5 vs. 15.3 kg/12 h; SEM = 1.3; interaction P < 0.01). This interaction was attributed to a greater reduction in meal frequency for ammonium treatment compared with sodium treatment when infused with propionate (3.9 vs. 7.2/12 h; SEM = 0.8) compared with acetate (6.6 vs. 7.0/12 h; SEM = 0.8), indicating that infusion of ammonium propionate reduced hunger. Meal size was decreased by infusion of propionate compared with acetate, but was not affected by ammonium compared with sodium, indicating that ammonium did not affect satiety. Mechanisms to explain the interactions between ammonium and propionate on meal frequency and feed intake warrant further investigation. [ABSTRACT FROM AUTHOR]

A decision process has proven effective in three activities that are key to value creation: choosing an excellent strategy, actually bringing about change, and operating effectively with the new strategy. The dialogue is between a decision board and the strategy team as they work through six steps of a decision process. This process is focused on alternatives and implementation and is founded in decision analysis. Strategy frameworks and structuring tools are key to assessing the business situation. Risk and value trade-offs are made explicit, leading to concrete proposals to add value and reduce risk. Explicit plans for action are developed as the strategic alternative is chosen. Companies have developed strategy insights using this process, as we illustrate with examples from the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Phenylketonuria (PKU) is an inborn error of phenylalanine metabolism primarily treated through a phenylalanine-restrictive diet that is frequently supplemented with an amino acid formula to maintain proper nutrition. Little is known of the effects of these dietary interventions on the gut microbiome of PKU patients, particularly in adults. In this study, we sequenced the V4 region of the 16S rRNA gene from stool samples collected from adults with PKU (n = 11) and non-PKU controls (n = 21). Gut bacterial communities were characterized through measurements of diversity and taxa abundance. Additionally, metabolic imputation was performed based on detected bacteria. Gut community diversity was lower in PKU individuals, though this effect was only statistically suggestive. A total of 65 genera across 5 phyla were statistically differentially abundant between PKU and control samples (p < 0.001). Additionally, we identified six metabolic pathways that differed between groups (p < 0.05), with four enriched in PKU samples and two in controls. While the child PKU gut microbiome has been previously investigated, this is the first study to explore the gut microbiome of adult PKU patients. We find that microbial diversity in PKU children differs from PKU adults and highlights the need for further studies to understand the effects of dietary restrictions. [ABSTRACT FROM AUTHOR]

Studies have demonstrated that environmental, host genetic, and socioeconomic factors influence the breast cancer prevalence landscape with a far-reaching influence on racial disparity to subtypes of breast cancer. To understand whether breast tissue harbors race-specific microbiota, we performed 16S rRNA gene-based sequencing of retrospective tumor and matched normal tissue adjacent to tumor (NAT) samples collected from Black non-Hispanic (BNH) and White non-Hispanic (WNH) women. Analysis of Triple Negative Breast cancer (TNBC) and Triple Positive Breast Cancer (TPBC) tissues for microbiota composition revealed significant differences in relative abundance of specific taxa at both phylum and genus levels between WNH and BNH women cohorts. Our main findings are that microbial diversity as measured by Shannon index was significantly lower in BNH TNBC tumor tissue as compared to matched NAT zone. In contrast, the WNH cohort had an inverse pattern for the Shannon index, when TNBC tumor tissue was compared to the matched NAT. Unweighted Principle Coordinates Analysis (PCoA) revealed a distinct clustering of tumor and NAT microbiota in both BNH and WNH cohorts. [ABSTRACT FROM AUTHOR]

Maternal separation with early weaning (MSEW) is a popular early life stress (ELS) model in rodents, which emulates childhood neglect through scheduled mother-offspring separation. Although variations of ELS models, including maternal separation and MSEW, have been published for the mouse species, the reported results are inconsistent. Corticosterone is considered the main stress hormone involved in regulating stress responses in rodents—yet generating a robust and reproducible corticosterone response in mouse models of ELS has been elusive. Considering the current lack of standardization for MSEW protocols, these inconsistent results may be attributed to variations in model methodologies. Here, we compared the effects of select early wean diet sources—which are the non-milk diets used to complete early weaning in MSEW pups—on the immediate stress phenotype of C57BL/6J mice at postnatal day 21. Non-aversive handling was an integral component of our modified MSEW model. The evaluation of body weight and serum corticosterone revealed the early wean diet to be a key variable in the resulting stress phenotype. Interestingly, select non-milk diets facilitated a stress phenotype in which low body weight was accompanied by significant corticosterone elevation. Our data indicate that dietary considerations are critical in MSEW-based studies and provide insight into improving the reproducibility of key stress-associated outcomes as a function of this widely used ELS paradigm. [ABSTRACT FROM AUTHOR]