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Full-Text Articles in Life Sciences

Conjugated Linoleic Acids Alter Body Composition Differently According To Physiological Age In Moulard Ducks, Jeff Fesler, Daniel Peterson Dec 2013

Conjugated Linoleic Acids Alter Body Composition Differently According To Physiological Age In Moulard Ducks, Jeff Fesler, Daniel Peterson

Master's Theses

Conjugated linoleic acids (CLA) have been shown to have remarkable yet inconsistent metabolic effects in mice, rats, hamsters, chickens, cattle, and humans. In particular, effects on lipogenesis vary with tissue, physiological state and specie. In this study we tested the hypothesis that CLA would differentially affect ducks of the same genetic background but of differing age. Growing (7 wk) and maintenance (11 wk) Moulard ducks were grouped by age and fed a standard diet supplemented with either 5% soybean oil (control) or 5% CLA isomer mixture. Animals were harvested after 3 weeks or 6 weeks for assessment of body composition …


In Vivo And In Vitro Digestibility Of A Complete Pelleted Feed In Horses, Cassandra Renee Sweeney Aug 2012

In Vivo And In Vitro Digestibility Of A Complete Pelleted Feed In Horses, Cassandra Renee Sweeney

Master's Theses

ABSTRACT

COMPLETION OF AN IN VIVO DIGESTIBILITY TRIAL IN HORSES AND IN VITRO DIGESTIBILITY ASSAY DEVELOPMENT

Cassandra Renee Sweeney

In vivo analysis of equine feed digestibility has been the gold standard since the late 1800's, although it can be time consuming, costly, and labor intensive. In vitro digestibility analysis may be more economical and beneficial to both feed manufacturers and consumers. The availability of accurate in vivo data is crucial for critical evaluation and validation of any potential in vitro method (Coles et al., 2005). Ten adult American quarter horse geldings were used in the in vivo digestibility evaluation of …


The Ma-10 Cell Line As A Model Of Insl3 Regulation And Leydig Cell Function, Mary E. Strong Jun 2011

The Ma-10 Cell Line As A Model Of Insl3 Regulation And Leydig Cell Function, Mary E. Strong

Master's Theses

Leydig cells produce testosterone in response to luteinizing hormone (LH) via the cyclic adenosine monophosphate (cAMP)/protein kinase A pathway. Additionally, these cells are responsible for producing insulin-like peptide 3 (INSL3), a peptide hormone that is essential for testicular descent. The insl3 promoter in Leydig cells can be activated by cAMP through the transcription factor Nur77, which has also been shown to regulate the promoters of the steroidogenic enzymes, cyp17 and 3b-hsd. While the mechanism of LH action on testosterone production is well characterized, the effect of LH on insl3 abundance has yet to be shown directly. The MA-10 …


Studying Milk Coagulation Kinetics With Laser Scanning Confocal Microscopy, Image Processing, And Computational Modeling, Richard Joseph Hennessy Jun 2011

Studying Milk Coagulation Kinetics With Laser Scanning Confocal Microscopy, Image Processing, And Computational Modeling, Richard Joseph Hennessy

Master's Theses

The kinetics of milk coagulation are complex and still not well understood. A deeper understanding of coagulation and the impact of the relevant factors would aid in both cheese manufacturing and also in determining the nutritional benefits of dairy products. A method using confocal microscopy was developed to follow the movement of milk fat globules and the formation of a milk protein network during the enzyme-induced coagulation of milk. Image processing methods were then used to quantify the rate of coagulation. It was found that the texture of the protein network is an indicator of the current status of the …


Nitric Oxide Synthesis By Chicken Macrophages Results In Coordinated Changes Of Multiple Arginine Transporters, Michael Moulds Apr 2011

Nitric Oxide Synthesis By Chicken Macrophages Results In Coordinated Changes Of Multiple Arginine Transporters, Michael Moulds

Master's Theses

Arginine transport is primarily mediated by the cationic amino acid transporters (CATs) in mammalian cells, but in aves the y+, b0,+ and B0,+ transport systems have also been observed. Arginine is the limiting catabolic substrate required for the production of nitric oxide (NO), a highly reactive compound that acts as a signaling molecule or killing compound. NO is synthesized by inducible nitric oxide synthase (iNOS) by macrophages for pathogen clearance. In mammals, CAT-2B is responsible for ARG import in the macrophage for NO synthesis, but the chicken CAT-2B isoform does not transport ARG. Therefore the objective …


The Development Of A Novel Technique To Evaluate Binding Between Probiotic Bacteria And Phospholipids, And The Creation Of A Dairy-Based Food Product Rich In Milk Bioactives, Megan Ann Cleveland Mar 2011

The Development Of A Novel Technique To Evaluate Binding Between Probiotic Bacteria And Phospholipids, And The Creation Of A Dairy-Based Food Product Rich In Milk Bioactives, Megan Ann Cleveland

Master's Theses

Probiotic bacteria are increasingly prevalent in food and nutritional products today. These remarkable microorganisms are capable of imparting exceptional health benefits on their host, including prevention of infection by pathogens and stimulation of immune system function. Their most common mode of delivery is through dairy products (e.g. yogurt), which are also one of their preferred habitats. The interactions between probiotic bacteria and dairy systems have been studied, but are still not well discerned. There is a need for better understanding of these associations, as well as those surrounding the mode of bacterial transfer from the food product to the human …


Intake, Apparent Digestibility, And Digesta Passage In Leopard Tortoises (Geochelone Pardalis) Fed A Complete, Extruded Feed, Laura Evelyn Lickel Mar 2011

Intake, Apparent Digestibility, And Digesta Passage In Leopard Tortoises (Geochelone Pardalis) Fed A Complete, Extruded Feed, Laura Evelyn Lickel

Master's Theses

The influence of feeding juvenile female leopard tortoises (Geochelone pardalis, n=18) a commercially available, complete, extruded feed three (3) or seven days (7) per week on dry matter and digestible energy intake, apparent digestibility of dry matter, organic matter, gross energy and fiber fractions, animal body weight and measurements, digesta transit time, rate of passage, and indigestible fill was evaluated. Both feeding frequencies are commonly practiced with captive tortoises. When fed 7 compared to 3 days per week, dry matter and digestible energy intake was greater. Tortoises gained more g BW, but not when adjusted per kg initial …


Characterization Of The Equine Spermadhesin Hsp-7 Found On Stallion Spermatozoa As It Relates To Stallion Fertility And Sperm Capacitation, Melodee Kathleen Heidmiller Mar 2011

Characterization Of The Equine Spermadhesin Hsp-7 Found On Stallion Spermatozoa As It Relates To Stallion Fertility And Sperm Capacitation, Melodee Kathleen Heidmiller

Master's Theses

Equine spermadhesin HSP-7 is a 14 kDa protein isolated from stallion seminal plasma and present on the surface of spermatozoa. HSP-7 displays carbohydrate and zona-pellucida binding properties, but the physiological role in equine fertilization is not well defined. HSP-7 has 98% amino acid sequence homology with the well-studied boar spermadhesin, AWN. Currently, these two proteins are considered to have the same reproductive function. Immunofluorescence studies presented here show that the stallion and boar spermadhesins are localized to different segments on spermatozoa. The variation in molecular compartmentalization of spermadhesin molecules in different species suggests that these structurally related proteins could be …


Comparisons Of Fish Species Inside And Outside Of Marine Protected Areas Off The South Central Coast Of California, David E. Rasmussen Oct 2010

Comparisons Of Fish Species Inside And Outside Of Marine Protected Areas Off The South Central Coast Of California, David E. Rasmussen

Master's Theses

COMPARISONS OF FISH SPECIES INSIDE AND OUTSIDE OF MARINE PROTECTED AREAS OFF THE SOUTH CENTRAL COAST OF CALIFORNIA

David E. Rasmussen

From 2004-2008 and 2008-2009 Cal Poly University researchers conducted two separate tag and recapture studies of nearshore fish populations along California’s central coast. Three locations were sampled that have experienced different degrees of fishing pressure. Big Creek MPA has been closed to all fishing from 1993 onwards and is the farthest from port of all locations. Cambria lies closest to port of the three locations and because of this has the highest fishing pressure. Piedras Blancas lies midway between …


Effect Of Feeding Zilpaterol Hydrochloride For 20 Days To Calf-Fed Holstein Steers With A 3 Or 10 Day Withdrawal Period Antemortem On Carcass Characteristics And Tenderness, Andrew D. Hosford Aug 2010

Effect Of Feeding Zilpaterol Hydrochloride For 20 Days To Calf-Fed Holstein Steers With A 3 Or 10 Day Withdrawal Period Antemortem On Carcass Characteristics And Tenderness, Andrew D. Hosford

Master's Theses

The effect of feeding Zilpaterol hydrochloride (ZH) with a 3 or 10 d withdrawal (WD) period to calf-fed Holstein steers (N=2993) on carcass characteristics and tenderness were evaluated in a feed lot experiment. Cattle were fed 0 or 8.3 mg/kg of ZH for the final 20 d of the feeding period, each treatment level was assigned a WD period of either 3 or 10 d. Treatment groups consisted of Control 3 d WD (C3) and 10 d WD (C10), and ZH fed 3 day WD (Z3) and 10 d WD (Z10). Cattle were slaughtered at a commercial facility, carcasses chilled …


Growth Hormone Alters Components Related To Differentiation, Metabolism And Milk Synthesis And Secretion In Mac-T Cells, Tasha Lynn Johnson Jun 2010

Growth Hormone Alters Components Related To Differentiation, Metabolism And Milk Synthesis And Secretion In Mac-T Cells, Tasha Lynn Johnson

Master's Theses

The mammary alveolar cell-T (MAC-T) cell line is able to uniformly differentiate and secrete casein proteins in response to dexamethasone, insulin and prolactin and is extensively used to study bovine mammary epithelial cell function. Growth hormone (GH) has been shown to increase milk protein synthesis both in vivo and in mammary cell models, and induce cytoskeletal rearrangement in 3T3 fibroblast cell line and a Chinese hamster ovary (CHO) cell line. Few studies have focused on identifying the mechanisms involved in differentiated MAC-T cells’ response to GH. We tested the hypothesis that MAC-T cells would respond directly to GH and that …


The Presence Of Micropterus Salmoides (Largemouth Bass) Influences The Populations Of Rana Draytonii (California Red-Legged Frog) And Pseudacris Regilla (Pacific Treefrog) In Two Ponds In Santa Barbara County, California, Kenneth Lee Gilliland Feb 2010

The Presence Of Micropterus Salmoides (Largemouth Bass) Influences The Populations Of Rana Draytonii (California Red-Legged Frog) And Pseudacris Regilla (Pacific Treefrog) In Two Ponds In Santa Barbara County, California, Kenneth Lee Gilliland

Master's Theses

Alien fish have been implicated in the decline of Rana draytonii (California red-legged frog) and Pseudacris regilla (Pacific treefrog) populations. Micropterus salmoides (largemouth bass) is a common sport fish that has been introduced into the sympatric range of these two anuran species; however, no studies have investigated the individual influence that this alien fish has on these two species. I conducted M. salmoides control or eradication experiments during a four year study in two ponds within the Transverse Mountain Range of Santa Barbara County, California. Changes in the densities of all life stages of R. draytonii and P. regilla were …


Impact Of Dietary Arginine On Immunity In Broiler Chicks, Jennifer Lynn D'Amato Oct 2009

Impact Of Dietary Arginine On Immunity In Broiler Chicks, Jennifer Lynn D'Amato

Master's Theses

Arginine (ARG) is an immunologic modulator due in part to its role as a substrate for leukocytes. Therefore, the objective of these studies was to evaluate the impact of dietary ARG on ARG utilization in peripheral blood mononuclear cells (PBMC) and thymocytes in broiler chicks as they provide a model that is not confounded by de novo ARG synthesis. Several experiments were performed to measure: 1) ARG transporters as markers of ARG utilization by leukocytes; 2) thymocyte proliferation; 3) PBMC phenotype, and 4) ARG’s impact on the acute phase response (APR). In experiment 1, chicks were fed diets containing 1.20% …


Impact Of Weed Management Practices On Grapevine Growth, Yield Components, Plant And Arthropod Abundance, And Carabid Seed Predation In Paso Robles Vineyard, Paolo Sanguankeo Sep 2009

Impact Of Weed Management Practices On Grapevine Growth, Yield Components, Plant And Arthropod Abundance, And Carabid Seed Predation In Paso Robles Vineyard, Paolo Sanguankeo

Master's Theses

In the Central Coast of California, USA, wine grape growers are making efforts to identify weed control practices that promote biodiversity in their vineyards while maintaining yields. A field study was conducted in Paso Robles, CA in 2006 and 2007 evaluating the effect on Zinfandel grape-vine growth and production, groundcover plant, and ground dwelling arthropod communities of five weed control practices: 1) flumioxazin, 2) simazine, 3) cultivation, 4) cover crop, and 5) untreated control.

The herbicide treatments had the lowest weed biomass followed by the cultivation, being approximately 10 and 2 times lower than the weed biomass of either the …


Viability Of Alternative Genetic Improvement Strategies Using Whole Genome Selection On Commercial Dairy Operations, Levi W.M. Gassaway Jun 2009

Viability Of Alternative Genetic Improvement Strategies Using Whole Genome Selection On Commercial Dairy Operations, Levi W.M. Gassaway

Master's Theses

The objective of this thesis was to determine the viability of alternative genetic improvement strategies (GIS). Each alternative GIS combined the use of whole genome selection (WGS) with common reproductive methods (non-sexed semen artificial insemination (AI), sexed semen AI, embryo transfer utilizing non-sexed semen AI) that can be found on a commercial dairy operation. The viability of each GIS was determined using a discounted gene flow model, designed with parameters of a typical western dairy operation, to evaluate the following variables: reproductive method, selection intensity, accuracy of prediction and female age-class. Of the GIS investigated, a heifer-based strategy that used …


Effects Of Filtration Temperature And Heat Treatment On Composition And Rheological Properties Of Whole Milk Ultrafiltration Retentates, John W. Montella Oct 2008

Effects Of Filtration Temperature And Heat Treatment On Composition And Rheological Properties Of Whole Milk Ultrafiltration Retentates, John W. Montella

Master's Theses

ABSTRACT

Effects of Filtration Temperature and Heat Treatment on Composition and Rheological Properties of Whole Milk Ultrafiltration Retentates

John William Montella

For the first part of my thesis, the effects of filtration temperature and heat treatment on the compositional properties of whole milk Ultrafiltration retentate (UF) were studied. Ultrafiltration is primarily run at temperatures in the range of 50-55°C but more and more plants are starting to filter at refrigeration temperatures. In the ultrafiltration of milk, filtration temperature can affect the composition of the retentate by affecting the chemistry of milk components. The application of a pasteurization step can also …