Life Sciences Commons^™

Inhibition Of Growth And Ammonia Production Of Ruminal Hyper Ammonia-Producing Bacteria By Chinook Or Galena Hops After Long-Term Storage, Michael D. Flythe, Brittany E. Harlow, Glen E. Aiken, Gloria L. Gellin, Isabelle A. Kagan, Jesse Pappas

Animal and Food Sciences Faculty Publications

Surplus hops (Humulus lupulus L.) that are not needed by the brewing industry could be used as a feed supplement for cattle and other ruminants. Previous research indicates that antimicrobial hops plant secondary metabolites (i.e., α- and β-acids) inhibit methane and ammonia production and promote the growth of ruminant animals. The goal was to determine that hop pellets produced for brewing still possessed the requisite antimicrobial activity after 5-year storage. HPLC (high performance liquid chromatography) analysis indicated that the α- and β-acid concentrations in two varieties of hops were relatively stable after 5 years of storage under N_{2 …}

Mperiod2Brdm1 And Other Single Period Mutant Mice Have Normal Food Anticipatory Activity, Julie S. Pendergast, Robert H. Wendroth, Rio C. Stenner, Charles D. Keil, Shin Yamazaki

Biology Faculty Publications

Animals anticipate the timing of food availability via the food-entrainable oscillator (FEO). The anatomical location and timekeeping mechanism of the FEO are unknown. Several studies showed the circadian gene, Period 2, is critical for FEO timekeeping. However, other studies concluded that canonical circadian genes are not essential for FEO timekeeping. In this study, we re-examined the effects of the Per2^Brdm1 mutation on food entrainment using methods that have revealed robust food anticipatory activity in other mutant lines. We examined food anticipatory activity, which is the output of the FEO, in single Period mutant mice. Single Per1, Per2 …

Pituitary Genomic Expression Profiles Of Steers Are Altered By Grazing Of High Vs. Low Endophyte-Infected Tall Fescue Forages, Qing Li, Raquel Hegge, Phillip J. Bridges, James C. Matthews

Animal and Food Sciences Faculty Publications

Consumption of ergot alkaloid-containing tall fescue grass impairs several metabolic, vascular, growth, and reproductive processes in cattle, collectively producing a clinical condition known as “fescue toxicosis.” Despite the apparent association between pituitary function and these physiological parameters, including depressed serum prolactin; no reports describe the effect of fescue toxicosis on pituitary genomic expression profiles. To identify candidate regulatory mechanisms, we compared the global and selected targeted mRNA expression patterns of pituitaries collected from beef steers that had been randomly assigned to undergo summer-long grazing (89 to 105 d) of a high-toxic endophyte-infected tall fescue pasture (HE; 0.746 μg/g ergot alkaloids; …

Hops (Humulus Lupulus L.) Bitter Acids: Modulation Of Rumen Fermentation And Potential As An Alternative Growth Promoter, Michael D. Flythe, Isabelle A. Kagan, Yuxi Wang, Nelmy Narvaez

Animal and Food Sciences Faculty Publications

Antibiotics can improve ruminant growth and efficiency by altering rumen fermentation via selective inhibition of microorganisms. However, antibiotic use is increasingly restricted due to concerns about the spread of antibiotic-resistance. Plant-based antimicrobials are alternatives to antibiotics in animal production. The hops plant (Humulus lupulus L.) produces a range of bioactive secondary metabolites, including antimicrobial prenylated phloroglucinols, which are commonly called alpha- and beta-acids. These latter compounds can be considered phyto-ionophores, phytochemicals with a similar antimicrobial mechanism of action to ionophore antibiotics (e.g., monensin, lasalocid). Like ionophores, the hop beta-acids inhibit rumen bacteria possessing a classical Gram-positive cell envelope. This …

Glucans And The Poultry Immune System, Jacquie Jacob, Anthony J. Pescatore

Animal and Food Sciences Faculty Publications

With the reduced availability of antibiotics, poultry producers are looking for feed additives to stimulate the immune system of their birds. Some beta-glucans have been shown to improve gut health in poultry subjected to a bacterial challenge, to increase the flow of new immunocytes into the various lymphoid organs, to increase macrophage function, to increase antibody titers after a vaccination and to function as an anti-inflammatory immunomodulator. As a result, beta-glucans may provide a tool for producers trying to reduce or eliminate the use of antibiotics in poultry diets.

Disappearance And Appearance Of An Indigestible Marker In Feces From Growing Pigs As Affected By Previous- And Current-Diet Composition, Brandy M. Jacobs, John F. Patience, Merlin D. Lindemann, Kenneth J. Stalder, Brian J. Kerr

Animal and Food Sciences Faculty Publications

Background: Indigestible markers are commonly utilized in digestion studies, but the complete disappearance or maximum appearance of a marker in feces can be affected by diet composition, feed intake, or an animal’s BW. The objectives of this study were to determine the impact of previous (Phase 1, P1) and current- (Phase 2, P2) diet composition on marker disappearance (Cr) and appearance (Ti) in pigs fed 3 diets differing in NDF content.

Results: When pigs were maintained on the 25.1, 72.5, and 125.0 g/kg NDF diets, it took 5.1, 4.1, and 2.5 d, respectively, for Cr levels to decrease below the …

Reactivity Of Ketyl And Acetyl Radicals From Direct Solar Actinic Photolysis Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The variable composition of secondary organic aerosols (SOA) contributes to the large uncertainty for predicting radiative forcing. A better understanding of the reaction mechanisms leading to aerosol formation such as for the photochemical reaction of aqueous pyruvic acid (PA) at λ ≥ 305 nm can contribute to constrain these uncertainties. Herein, the photochemistry of aqueous PA (5-300 mM) continuously sparged with air is re-examined in the laboratory under comparable irradiance at 38° N at noon on a summer day. Several analytical methods are employed to monitor the time series of the reaction, including (1) the derivatization of carbonyl (C═O) functional …

Exogenous Lactobacilli Mitigate Microbial Changes Associated With Grain Fermentation (Corn, Oats, And Wheat) By Equine Fecal Microflora Ex Vivo, Brittany E. Harlow, Laurie M. Lawrence, Patricia A. Harris, Glen E. Aiken, Michael D. Flythe

Animal and Food Sciences Faculty Publications

Cereal grains are often included in equine diets. When starch intake exceeds foregut digestion starch will reach the hindgut, impacting microbial ecology. Probiotics (e.g., lactobacilli) are reported to mitigate GI dysbioses in other species. This study was conducted to determine the effect of exogenous lactobacilli on pH and the growth of amylolytic and lactate-utilizing bacteria. Feces were collected from 3 mature geldings fed grass hay with access to pasture. Fecal microbes were harvested by differential centrifugation, washed, and re-suspended in anaerobic media containing ground corn, wheat, or oats at 1.6% (w/v) starch and one of five …

Inhibition Of Listeria Monocytogenes On Ready-To-Eat Meats Using Bacteriocin Mixtures Based On Mode-Of-Action, Paul Priyesh Vijayakumar, Peter M. Muriana

Animal and Food Sciences Faculty Publications

Bacteriocin-producing (Bac⁺) lactic acid bacteria (LAB) comprising selected strains of Lactobacillus curvatus, Lactococcus lactis, Pediococcus acidilactici, and Enterococcus faecium and thailandicus were examined for inhibition of Listeria monocytogenes during hotdog challenge studies. The Bac⁺ strains, or their cell-free supernatants (CFS), were grouped according to mode-of-action (MOA) as determined from prior studies. Making a mixture of as many MOAs as possible is a practical way to obtain a potent natural antimicrobial mixture to address L. monocytogenes contamination of RTE meat products (i.e., hotdogs). The heat resistance of the bacteriocins allowed the use of pasteurization to …

Development And Evaluation Of A Low-Cost Probe-Type Instrument To Measure The Equilibrium Moisture Content Of Grain, Paul R. Armstrong, Samuel G. Mcneill, Naomi Manu, Augustine Bosomtwe, James K. Danso, Enoch Osekre, George Opit

Biosystems and Agricultural Engineering Faculty Publications

Storage of grain in bags is common in Africa, Asia, and many other less developed countries making a bag probing method well-suited for moisture content (MC) measurement. A low-cost meter was developed under a USAID project to reduce post-harvest loss (PHL). The meter, referred to as the PHL meter, measures the MC of maize and other grains based on relative humidity (RH) and temperature (T) measurements obtained by a small digital sensor located in the tip of a tubular probe that can be inserted into bags of grain or other grain bulks. Measurements are used by equilibrium moisture content (EMC) …

Controlled Oxidative Modification With Glucose Oxidase To Enhance The Rheological And Gelling Properties Of Myofibrillar Proteins, Xu Wang

Theses and Dissertations--Animal and Food Sciences

This study investigated the feasibility of oxidative modification with glucose oxidase (GluOx) to enhance the rheological and gelling properties of myofibrillar protein. Differential oxidative modifications of myofibrillar protein (MP) by hydroxyl radicals generated in an enzymatic system with glucose oxidase (GluOx) in the presence of glucose/FeSO₄ compared to a Fenton system (H₂O₂/FeSO₄) were investigated. Firmer and more elastic MP gels were produced by the GluOx-oxidizing system than by the Fenton system at comparable H₂O₂ levels due to an altered radical reaction pathway.

The study further explored the effect of GluOx-mediated …

Equilibrium Moisture Content Of Kabuli, Chickpea, Black Sesame, And White Sesame Seeds, Paul R. Armstrong, Elizabeth B. Maghirang, Bhadriraju Subramanyam, Samuel G. Mcneill

Biosystems and Agricultural Engineering Faculty Publications

Sesame and chickpea are important crops in Ethiopia because both are major export crops that generate much revenue for both small farmers and the country as a whole. However, there is a lack of information about the fundamental equilibrium moisture content (EMC) relationships among these crops, which would help facilitate better monitoring and storage. Therefore, EMC adsorption and desorption prediction models based on temperature (T) and relative humidity (RH) were developed for the modified Chung-Pfost and modified Henderson models for Kabuli chickpea (KC), black sesame (BS), and white sesame (WS) seeds. The samples for conducting the adsorption and desorption tests …

The Survival Of Various Pathogenic Organisms In Fats And Oils, Kelsey Ellen Lamb

Theses and Dissertations--Animal and Food Sciences

The research within this thesis sought to determine the ability of various animal derived fats and plant derived oils to support the survival of several pathogenic cocktails over a multitude of storage times. The Salmonella study explored the survival rate of a four strain Salmonella cocktail in beef tallow, pig lard, duck fat, coconut oil, and extra virgin olive oil over seven days at 26˚C and 37˚C storage. The animal fats and the coconut oil supported the survival of the bacteria until the conclusion of the study. The Shiga-toxin producing Escherichia coli study explored the survival rate of a five …

Proteome Basis Of Muscle‐Specific Beef Color Stability, Mahesh Narayanan Nair

Theses and Dissertations--Animal and Food Sciences

Fresh beef color is critical to consumers’ purchase decisions, and beef color stability is muscle-specific. Sarcoplasmic proteome plays a critical role in beef color stability. This dissertation focuses on the proteome basis of inter- and intra-muscular variations in beef color.

The first experiment examined the sarcoplasmic proteome of three beef muscles with differential color stability, i.e., longissimus lumborum (LL), psoas major (PM), and semitendinosus (ST), during wet-aging. LL, PM, and ST (n = 8) were subjected to wet-aging for 0, 7, 14, and 21 days. On each aging day, steaks were fabricated, and color and other biochemical attributes were evaluated …

The Use Of Lactobacillus Salivarius L28 As A Bioprotective Culture In Dry Fermented Sausages, Kathy Flynt Collins

Theses and Dissertations--Animal and Food Sciences

A challenge study to validate a 5 log₁₀ CFU/g reduction of non-O157 Shiga-toxin producing Escherichia coli (STEC) in dry fermented sausage (DFS) was performed. A 4.49 ± 0.474 log₁₀ CFU/g was achieved over two trials. The results indicated that the process was not effective in reducing the pathogen to the level required of most pathogens by the USDA.

Lactobacillus salivarius L28 (L28) was screened in vitro for the ability to inhibit STEC utilizing the paper disk diffusion method. This strain is a known bacteriocin producer. The results revealed that L28 would be a good candidate for use as …

Feeding The Soul: Voices Of Kentucky Women Combating Child Hunger, Mya Oneisha Price

Theses and Dissertations--Community & Leadership Development

This study addresses the overarching topic of food insecurity by giving voice to individuals who are dedicating their careers toward combating child food insecurity throughout their communities. Voices are uplifted through the representation of narratives by volunteer coordinators overseeing child feeding programs, which have been established throughout Kentucky as an effort to help alleviate child hunger. This study is guided by London’s theory on career motivation, with the outcomes of this study serving as a pilot for future research centered around individuals working to combat child food insecurity. The narratives collected from this study will be used as a resource …