Biochemistry, Biophysics, and Structural Biology Commons^™

Plant Cell Wall Composition And In Vitro Fermentation Characteristics Of Cool-Season Forage Grasses From Two Growing Seasons In Central Kentucky, Sophia Danielle Newhuis

Theses and Dissertations--Animal and Food Sciences

Grass cell walls are rich in cellulose, hemicellulosic arabinoxylan (AX) polysaccharides, and lignin. AX structural differences such as degree and pattern of branching and the ester-linked phenolic acid content could affect plants’ digestibility when used as forage for livestock. However, there is little information about how these structural elements change over the growing season in the vegetative tissue of cool-season perennial grasses. Enhanced information about the cell wall composition and carbohydrate structure of forage material will provide a foundation for expanding our knowledge of how forage cell wall carbohydrate structures are utilized by ruminants. The objectives of this study were …

Arabinoxylan Structural Profiling Of Cool-Season Pasture Grasses Via High-Performance Anion-Exchange Chromatography With Pulsed Amperometric Detection (Hpaec-Pad) Analysis Of Endoxylanase Digests, Glenna Erin Joyce

Theses and Dissertations--Animal and Food Sciences

Arabinoxylan (AX) is a major structural polysaccharide found in the cell walls of monocots such as cereal grains and pasture grasses. The variety of AX structural components and substitution patterns contribute to AX structural diversity between different monocot species as well as plant tissues.

The rumen is the first digestion site of masticated food material in cattle and provides 70% of energy to host through fermentation of forage. There are many species of pasture grasses that act as a forage source. Differences in AX structure found in these pasture grasses may impact rumen microbial fermentation. Understanding the AX structure of …

Trade-Offs Shape Carotenoid-Based Color Variation In Redheaded Pine Sawfly (Neodiprion Lecontei) Larvae, Maranda Gaines

Lewis Honors College Capstone Collection

Carotenoids serve various ecological roles in animals including coloration, immune responses, and vision. Carotenoid-derived coloration is greatly emphasized in the literature, particularly relating to mate choice and aposematic warning. However, the trade-offs between the color and non-color functions of carotenoids are not thoroughly explored. In the redheaded pine sawfly (Neodiprion lecontei), some larval populations have yellow pigmentation, using carotenoids derived from their diets for aposematic warning coloration. Other larval populations are white in color, having genetically lost the ability to produce the yellow pigment. Because carotenoids are essential to life functions in both the yellow and white populations, we aim …

Contractile Response Of Bovine Lateral Saphenous Vein To Ergotamine Tartrate Exposed To Different Concentrations Of Molecularly Imprinted Polymer, Manoj B. Kudupoje, James L. Klotz, Alexandros Yiannikouris, Karl A. Dawson, Kyle R. Mcleod, Eric S. Vanzant

Animal and Food Sciences Faculty Publications

Ergot alkaloids, in their active isomeric form, affect animal health and performance, and adsorbents are used to mitigate toxicities by reducing bioavailability. Adsorbents with high specificity (molecularly imprinted polymers: MIP) adsorb ergot alkaloids in vitro, but require evaluation for biological implications. Using ex vivo myography, synthetic polymers were evaluated for effects on the bioactivity of ergotamine tartrate (ETA). Polymers were first evaluated using isotherms. Lateral saphenous veins were collected from 17 steers for four independent studies: dose response of ETA, adsorbent dose response, validation of pre-myograph incubation conditions and MIP/ non-molecularly imprinted polymer (NIP) comparison. Norepinephrine normalized percent contractile response …

Influence Of Dietary Ractopamine And Supranutritional Supplementation Of Vitamin E On Proteome Profile Of Postmortem Beef Longissimus Lumborum Muscle, Hyun Mok Kim

Theses and Dissertations--Animal and Food Sciences

The effects of dietary ingredients on the proteome profile of postmortem beef longissimus lumborum (LL) muscle were evaluated. In the first experiment, the influence of dietary ractopamine on the whole-muscle proteome of beef LL was examined. Five proteins were differentially abundant between ractopamine-fed (RAC) and non-ractopamine fed (CON) groups. The differentially abundant proteins were over-abundant in RAC and were related to muscle structure development (F-actin-capping protein subunit beta-2 and PDZ and LIM domain protein-3), chaperone (heat shock protein beta-1), oxygen transportation (myoglobin), and glycolysis (L-lactate dehydrogenase A chain). These findings indicated that ractopamine influences the abundance of proteins associated with …

Progesterone Receptor And Prostaglandins Mediate Luteinizing Hormone-Induced Changes In Messenger Rnas For Adamts Proteases In Theca Cells Of Bovine Periovulatory Follicles, Erin L. Willis, Phillip J. Bridges, Joanne E. Fortune

Animal and Food Sciences Faculty Publications

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non‐rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin‐releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle‐stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post‐GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, ‐2, …

Use Of Genomic Tools To Discover The Cause Of Champagne Dilution Coat Color In Horses And To Map The Genetic Cause Of Extreme Lordosis In American Saddlebred Horses, Deborah G. Cook

Theses and Dissertations--Veterinary Science

Champagne dilution of coat color in horses is caused by dominant gene action. Three sire families were identified as segregating for this trait. Genome wide linkage analysis using 104 microsatellite DNA markers was used to map the gene to ECA14 (LOD > 11.0). Four genes, namely SPARC, SLC36A1, SLC36A2 and SLC36A3, were selected from the region implicated by linkage and their exons sequenced. DNA sequences were compared for two homozygotes for Champagne dilution, two heterozygotes and two horses without dilution. A single base change in exon 2 of SLC36A1 was found unique to horses exhibiting Champagne dilution. This change in base …

Sex Determination In Beetles: Production Of All Male Progeny By Parental Rnai Knockdown Of Transformer, Jayendra Nath Shukla, Subba Reddy Palli

Entomology Faculty Publications

Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms of T. castaneum transformer (Tctra) were identified. RNA interference-aided knockdown of Tctra in pupa or adults caused a change in sex from females to males by diverting the splicing of Tcdsx pre-mRNA to male-specific isoform. All the pupa and adults developed from Tctra …