Publications by authors named "Michael S Allen"

This experiment determined the effects of two different starch sources when offered twice a day to cows during the early postpartum period (1 to 23 d postpartum, treatment period) on dry matter intake (DMI), feeding behavior, and milk production. The subsequent effects on milk production in the carryover period (24 to 72 d) where cows received a common diet (grazed perennial ryegrass pasture plus concentrate supplements) were also measured. Thirty-two multiparous dairy cows were offered concentrate feed (8 kg DM/d) containing 5 kg DM of crushed wheat grain or ground corn grain (7 h in vitro starch digestibility of 65.

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The opioid epidemic is an evolving health crisis in need of interventions that target all domains of maladaptive changes due to chronic use and abuse. Opioids are known for their effects on the opioid and dopaminergic systems, in addition to neurocircuitry changes that mediate changes in behavior; however, new research lines are looking at complementary changes in the brain and gut. The gut-brain axis (GBA) is a bidirectional signaling process that permits feedback between the brain and gut and is altered in subjects with opioid use disorders.

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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.

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, the spirochetal agent of Lyme disease, utilizes a variety of strategies to evade and suppress the host immune response, which enables it to chronically persist in the host. The resulting immune response is characterized by unusually strong IgM production and a lack of long-term protective immunity. Previous studies in mice have shown that infection with also broadly suppresses host antibody responses against unrelated antigens.

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The effects of synthetic, free-amino acid diets, similar to those prescribed as supplements for (phenylketonuria) PKU patients, on gut microbiota and overall health are not well understood. In the current, multidisciplinary study, we examined the effects of a synthetically-derived, low-fiber, amino acid diet on behavior, cognition, gut microbiome composition, and inflammatory markers. A cohort of 20 male C57BL/6J mice were randomly assigned to either a standard or synthetic diet ( = 10) at post-natal day 21 and maintained for 13 weeks.

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Energy intake and partitioning are determined by many interacting factors and their prediction is the Achilles' heel of ration formulation. Inadequate energy intake can limit milk yield and reproductive performance, whereas excessive energy intake will increase body condition, increasing the risk of health and reproductive issues in the subsequent lactation. Ration composition interacts with the physiological state of cows, making it difficult to predict DMI and the partitioning of energy accurately.

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Background: Post-mortem microbial communities are increasingly investigated as proxy evidence for a variety of factors of interest in forensic science. The reported predictive power of the microbial community to determine aspects of the individual's post-mortem history (e.g.

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Extreme weather events can temporarily alter the structure of coastal systems and generate floodwaters that are contaminated with fecal indicator bacteria (FIB); however, every coastal system is unique, so identification of trends and commonalities in these episodic events is challenging. To improve our understanding of the resilience of coastal systems to the disturbance of extreme weather events, we monitored water quality, FIB at three stations within Clear Lake, an estuary between Houston and Galveston, and three stations in bayous that feed into the estuary. Water samples were collected immediately before and after Hurricane Harvey (HH) and then throughout the fall of 2017.

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Our objective was to evaluate the effects of corn grain varying in endosperm type and conserved as high-moisture or dry ground corn on dry matter intake (DMI), feeding behavior, ruminal fermentation, and yields of milk and milk components of cows in early to mid-lactation. Seven ruminally and duodenally cannulated Holstein cows (73 ± 39 d in milk; mean ± SD) were used in a duplicated 4 × 4 Latin square design with 21-d periods. A 2 × 2 factorial arrangement of treatments was used with main effects of corn grain endosperm type (floury or vitreous) conserved as high-moisture corn (HMC) or dry ground corn (DGC).

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Our objective was to evaluate the relative effects of endosperm type and conservation method of corn grain on ruminal kinetics, site of nutrient digestion, and flow of nitrogen fractions to the duodenum in lactating dairy cows. Seven ruminally and duodenally cannulated Holstein cows (73 ± 39 d in milk; mean ± SD) were used in a duplicated 4 × 4 Latin square design with 21-d periods. A 2 × 2 factorial arrangement of treatments was used, with main effects of corn grain endosperm type (floury or vitreous) and conserved as dry ground corn (DGC) or high-moisture corn (HMC).

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Our objective was to evaluate effects of corn grain endosperm type and fineness of grind on feed intake, feeding behavior, ruminal fermentation, and productive performance of lactating cows. Eight ruminally and duodenally cannulated Holstein cows in mid lactation (130 ± 42 d in milk; mean ± standard deviation) were used in a duplicated 4 × 4 Latin square design with 21-d periods. A 2 × 2 factorial arrangement of treatments was used with main effects of corn grain endosperm type (floury or vitreous) and fineness of grind of corn grain (fine or medium).

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Our objective was to evaluate effects of corn grain endosperm type and fineness of grind on feed intake, feeding behavior, and productive performance of lactating cows. Eight ruminally and duodenally cannulated Holstein cows in mid lactation (130 ± 42 d in milk; mean ± standard deviation) were used in a duplicated 4 × 4 Latin square design with 21-d periods. A 2 × 2 factorial arrangement of treatments was used with main effects of corn grain endosperm type (floury or vitreous) and fineness of grind (fine or medium).

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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 ( = 11) and non-PKU controls ( = 21).

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Our objective was to determine the effects of uncouplers of oxidative phosphorylation on the metabolism of propionate in liver tissue of dairy cows in the postpartum period. A total of 8 primiparous dairy cows were biopsied for liver tissue explants in 2 block-design experiments. Cows were 5.

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Our objective was to determine the temporal effects of increasing supply of propionate on propionate metabolism in liver tissue of dairy cows in the postpartum (PP) period. A total of 6 dairy cows [primiparous: n = 3, 9.00 ± 1.

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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.

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Chagas disease, caused by the hemoflagellate protist , affects nearly 6 million people worldwide, mainly in Latin America. Hematophagous triatomine insects ("kissing bugs") are the primary vectors of throughout the Americas and feed on a variety of animals, including humans. Control of triatomines is central to the control of infection.

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Air pollution exposure is known to contribute to the progression of cardiovascular disease (CVD) and there is increasing evidence that dysbiosis of the gut microbiome may also play a role in the pathogenesis of CVD, including atherosclerosis. To date, the effects of inhaled air pollution mixtures on the intestinal epithelial barrier (IEB), and microbiota profiles are not well characterized, especially in susceptible individuals with comorbidity. Thus, we investigated the effects of inhaled ubiquitous air-pollutants, wood-smoke (WS) and mixed diesel and gasoline vehicle exhaust (MVE) on alterations in the expression of markers of integrity, inflammation, and microbiota profiles in the intestine of atherosclerotic Apolipoprotein E knockout (ApoE) mice.

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Our objective was to determine the effects of uncouplers of oxidative phosphorylation on feeding behavior of lactating dairy cows. We hypothesized that uncouplers of oxidative phosphorylation would increase meal size and meal length and performed 2 experiments to test our hypothesis. In experiment 1, 4 late-lactation cows (345 ± 48.

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A faster rate of infusion of propionic acid into the rumen of cows in the postpartum period increased meal size compared with a slower rate of infusion in a previous experiment. Because propionate is anaplerotic and stimulates oxidation of acetyl coenzyme A (CoA) in the liver, and hepatic oxidation has been linked to satiety, this result was opposite to our expected response. We then hypothesized that the faster rate of infusion might have saturated the pathway for propionate metabolism in hepatocytes resulting in lower first-pass extraction by the liver.

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The objective of this research was to identify potential short-term metabolic bottlenecks of propionate metabolism in the liver of dairy cows in the postpartum (PP) period and how such bottlenecks are affected by feeding status. Propionate, produced primarily from the fermentation of starch, decreases dry matter intake for cows in the postpartum period, likely by stimulating oxidation of acetyl-CoA in the liver. In this study, 8 dairy cows [2 blocks of 4 cows each, 6.

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Background: The blacklegged tick, Ixodes scapularis, is the primary vector of the Lyme disease spirochete Borrelia burgdorferi in North America. Though the tick is found across the eastern United States, Lyme disease is endemic to the northeast and upper midwest and rare or absent in the southern portion of the vector's range. In an effort to better understand the tick microbiome from diverse geographic and climatic regions, we analysed the bacterial community of 115 I.

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The objective of this study was to determine the effects of 2 amounts of propionic acid (PA) infused intraruminally at 2 rates of infusion at the initiation of meals on the feeding behavior of Holstein cows in the postpartum period. We hypothesized that the amount and length of time of infusions would interact to affect feeding behavior: rapid infusion of a higher dose of PA would result in larger meal size with greater time between meals compared with a slower rate, whereas faster infusion of a lower dose of PA would reduce meal size and the time between meals compared with a slower infusion of the same dose. Eight ruminally cannulated, multiparous Holstein cows were used in a 4 × 4 Latin square design experiment.

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The global public health impact of relapsing fever (RF) spirochetosis is significant, since the pathogens exist on five of seven continents. The hallmark sign of infection is episodic fever and the greatest threat is to the unborn. With the goal of better understanding the specificity of B-cell responses and the role of immune responses in pathogenicity, we infected rhesus macaques with (a new world RF spirochete species) by tick bite and monitored the immune responses generated in response to the pathogen.

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OBJECTIVE To determine whether Mycobacterium bovis remains viable in ensiled forages. SAMPLE Alfalfa, mixed mostly grass, and corn silages. PROCEDURES For each of 10 sampling days, six 250-g replicate samples of each feedstuff were created and placed in a film pouch that could be vacuum sealed to simulate the ensiling process.

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