Animal Sciences Commons^™

Digestion And Rumen Fermentation In Precision-Fed Dairy Heifers On Low Or High Forage Rations At Four Levels Of Dry Distillers Grain, F. X. Suarez-Mena, G. J. Lascano, A. J. Heinrichs

Dairy Science

No abstract provided.

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 …

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 …

Managing The Lambing Enterprise, Erika Hucal

Animal Science

No abstract provided.

Technical Note: Feeding Zilpaterol Hydrochloride To Calf-Fed Holstein Steers Improves Muscle Conformation Of Top Loin Steaks, T. E. Lawrence, D. M. Allen, R. J. Delmore, J. L. Beckett, W. T. Nichols, M. N. Streeter, D. A. Yates, J. P. Hutcheson

Animal Science

The objective of this research was to evaluate changes in the muscle conformation of subprimal top-loins (M. longissimus lumborum) from calf-fed Holstein steers fed zilpaterol hydrochloride (ZH). Top-loins (n =100) were transversely cut into 2.54 cm-thick steaks, weighed, and objectively evaluated via image analysis software for muscle area, width, and length traits. Top-loin steaks from steers fed ZH were heavier (P < 0.01; 367 vs. 337 g) and average muscle area per steak was greater (P < 0.05; 80.9 vs. 77.2 cm²) as compared to steaks from control steers. Muscle width (medial–lateral) was not different (P = 0.23) between control steers and those fed ZH. However, steaks from steers fed ZH had greater (P < 0.05) depth (dorsal–ventral) than steaks from control steers throughout the top-loin. The increased muscle depth of top-loins from calf-fed Holstein steers fed ZH may improve the center-of-the-plate salability of a cut that has traditionally suffered from poor muscling.

Put Cultured Dairy Products On The School Lunch Menu, Phillip S. Tong

Dairy Science

No abstract provided.

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⁺, b^0,+ and B^0,+ 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 …

Organic Replacement Heifer Enterprise Budget For Walker Dairy, Colton Brodt

Agribusiness

This study was undertaken to determine if Walker Dairy could raise replacement heifers cheaper than the current market price.

The main objective of this report was to calculate how much it costs Walker Dairy to raise a heifer per head. Data collected went into the development of a heifer enterprise budget and determining an average market price. Transfer value in (drop calf price), feed, labor, operating and fixed costs were all factored into the total cost per animal. Also, the data was broken into four different sections of a heifers’ life to aid management in evaluating the cost of raising …

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

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

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 …

The Case For Simplifying Ingredient Statements, Phillip S. Tong

Dairy Science

No abstract provided.

Caffeine Metabolism And Cytochrome P450 Enzyme Mrna Expression Levels Of Genetically Diverse Inbred Mouse Strains, Neal Addicott, Michael Malfatti, Gabriela G. Loots

STAR Program Research Presentations

Cytochrome P450 (CYP) enzymes activate or eliminate medications and other xenobiotics, and Caffeine has been used as an indicator of activity for some CYPs. The natural genetic variation in the human population for caffeine metabolizing CYPs does not yet have an established animal model for comparison, but the natural variation in inbred mouse strains presents an attractive starting point. The project gave four different strains of mice a 40mg/kg dose of caffeine and sampled blood and liver tissue after 30 minutes. Samples were analyzed using High Performance Liquid Chromatography (HPLC), reverse transcription PCR (rtPCR), and quantitative PCR (qPCR). The DBA/2J …

The Effects Of Sexed Semen On Embryonic Development To The Blastocyst Stage, William E. Plummer, D. Beckett, A. Schaffner, B. Layport, J. Norman, C. Grimbleby, P. Wessinger, E. Pace, L. Kirscher, K. Matthews, T. Dorshorst

Animal Science

Sexed semen (SS) exhibits approximately 80% of the fertilizing ability of conventional semen (CS), and studies have shown that this continues through the 8-cell stage of bovine embryo development. At the time of this study, no information could be found that, when used for IVF and intracytoplasmic sperm injection (ICSI) development, had been carried to the blastocyst stage. In addition, questions have arisen regarding which of the measured sperm parameters are responsible for the difference between the SS and CS and contribute to this decline in fertility. The goals of this project were to evaluate the effects of using sexed …

Food Processors Look To Dairy Ingredients, Phillip S. Tong

Dairy Science

No abstract provided.

A Literature Review On Crossbreeding In Dairy Cattle, Philip Owens

Dairy Science

The objective of the literature review was to determine whether or not crossbreeding is a profitable and a viable option for the dairymen of today by reviewing the literature and experiments that have been conducted throughout the world by today’s dairy professionals and leaders. The Dairy market today is increasingly competitive and more and more dairymen are considering crossbreeding to decrease health costs and increase profitability. Price premiums from cheese plants are given to milk producers for high components like protein and fat. In recent studies done by universities and research facilities around the world, results have found promising numbers …

Burning Manure As An Economical Energy Source, Ron Machado

Dairy Science

The dairy industry is under pressure from increasing environmental regulations, falling prices, as well as very aggressive foreign competition. Manure management and electrical costs are one area dairymen can look to cut costs. My objective for this project was to determine how cost effective biomass gasification of manure is at generating electricity. The proposed project was designed for a manure production equal to a 3,000 cow herd. I used standard capital budgeting techniques to determine the efficiency of the project, primarily focusing on the net present value, internal rate of return, and payback period.

Institution Of Presynch Protocol, Justin Breedyk

Dairy Science

The objective of this study was to compare factors of reproductive efficiency between two separate ovulation synchronization programs, with one that includes presynchronization of all fresh cows and one that does not ovsynch cows until they have been found open after initial insemination. In recent years, reproductive efficiency has declined as other areas of the dairy business have continued to excel. The investigation was performed on two dairies in Hart, Texas, White River Ranch and VB Dairy. The dairies include herds of 5,000 and 3,000 milking cows, respectively. Data was retrieved using Dairy Comp 305 and covered a two month …

Effectiveness Of A Presynchronization Program Implemented On A Modern Dairy Facility, R. (Robert) E. Thommen

Dairy Science

The objective of this study was to determine the success of a presynchronization program implemented on a modern dairy facility. The study was conducted on a 1,400 cow dairy in the central valley of California. 86 cows were involved in the study during the summer months of June through September. Cows were either assigned in the synchronization program or placed in a control group based on the last digit of their identification. At 43 DIM, presync cows were injected with their first treatment of the synchronization program. Estrous cycles of the presync group were manipulated with treatments of Prostaglandin and …

Genotype And Breed Trend Influences On Citric Acid And Coagulation Times Of Raw Milk, Melissa Looney

Dairy Science

The objective of the study was to determine if citric acid levels measured in milk was related to genetic variants identified in Holstein and Jersey cows. The data used were milk samples collected from both Holstein and Jersey cows at Cal Poly, San Luis Obispo. Citric acid levels and other constituents were measured using FTIR methods with the FOSS MilkoscanTM FT2 on each sample. Genotypes were obtained for the DGAT 1 locus using polymerase chain reaction and an enzymatic digestion using the MWO I restriction enzyme. Observations were obtained on 13 Holsteins and 12 Jersey cows. Results indicated that citric …

Ultraviolet Light As An Adjunct Treatment To Pasteurization For Microbial Reduction In Milk Intended For Extended Shelf Life, Jacob Zonneveld

Dairy Science

The objective of this study was to determine whether ultraviolet light treatment of milk could be used in adjunct with pasteurization and to determine whether the microbial count in bulk tank raw milk was sufficient enough to receive significant results. Samples were collected from a bulk tank filled with 1600 gallons of raw Holstein and Jersey milk from the Cal Poly Dairy throughout the course of a week. Control (library) samples were also taken from the raw milk tank and stored without air or agitation for comparison. These samples were plated each day and examined 24 and 48 hours after …

Use Of An Activity Monitoring System As Part Of The Cal Poly Dairy Breeding Protocol, Trevor Nutcher

Dairy Science

The objective of this study, is to determine the effectiveness of an activity monitoring system as an integral part of the Cal Poly Dairy breeding protocol. Dairy herd reproductive efficiencies have dropped in the past 40 years. Increased milk production, and genetic advancements towards more milk production, have led to reproductive rates declining. An advanced breeding program is needed to become more efficient in this area. The study consisted of the evaluation of one option, Heatime™ by MICRO Dairy Logic, and comparing it to the commonly used programs in dairies today such as synchronization methods, pedometers, and other electronic detection …

Use Of Endovac-Bovi In Pre-Weaned Calves, Jena Glasgow

Dairy Science

No abstract provided.

Cal Poly Embryo Recovery Record System, Kelsey Donahoo-Cheda

Dairy Science

No abstract provided.

Cystic Ovaries In Dairy Cattle, Lacey Morgan Rosenberg

Dairy Science

The objective of this literature review was to determine the potential causes and factors affecting the incidence of ovarian cysts in dairy cattle as well as to examine functionality of various preventative methods and treatments of cysts. The end product was to be a document outlining all the information available on the three different types of cysts that can develop on the bovine ovary, follicular cysts, luteal cysts, and cystic corpora lutea. The literature that was reviewed, most in the forms of research papers, articles, and reviews, came primarily from scientific journals and published books. The literature reviewed was only …

Controlling The Mineral Content Of Sweet Whey Powder In An Industrial Setting, Matthew W. Sawyer

Dairy Science

The objective of this project was to reduce the final ash content of sweet whey powder. The data for this project was collected over a two-week period, from July 13th to July 27th 2010 in a dairy plant in the Mid-West of the United States. The data is composed of particle size test, ash test, and pH test. The conclusions of this study are that multiple pre-heat treatment tank changes contribute to mineral content by requiring more buffering than usual. The low pH of this pre-heat liquid forces a need for more buffering. Particle segregation may play a role in …

A Comparison Between The Dhia Test For Somatic Cell Counts Compared To Porta Side Test On The Individual Quarters Of The High Scc Cows At The Cal Poly Dairy, Melissa Zimmer

Dairy Science

The objective of my senior project is to determine if California Mastitis Test (CMT) and the Porta Side Somatic Cell Count (SCC) Test is equivalent to the DHIA laboratory somatic cell test. The data was taken from the Cal Poly Dairy on October 19th, 2010. Samples were taken from eight Holstein cows during milking time and the tests were run in the barn. These eight cows were the highest somatic cell count cows at the Cal Poly Dairy on the previous test day October 9, 2010. During milking the cows were pre and post dipped before the samples were taken. …

Rangeland Condition Assessment Of A Portion Of The Cal Poly Sheep Unit, Colin S. Mckim

Animal Science

This rangeland condition assessment was conducted as part of the Cal Poly Rangeland Condition Assessment Project. Five pastures comprising 31.7 acres at the Cal Poly sheep unit were assessed to collect baseline ecological information. Methods used were Line-point Intercept, Belt Transect, Residual Dry Matter, and the rangeland health indicators recommended by Pyke et al., 2002. Additionally, a preliminary species list was collected. The rangeland health assessment method found all pastures to have no to slight departure from the local reference area when evaluated for soil and site stability, hydrologic function, and biotic integrity.

A Novel Method For Evaluating The Release Of Fermentable Sugars From Cellulosic Biomass, Rafael Jiménez-Flores, Gina Fake, Jennifer Carroll, Elizabeth Hood, John Howard

Dairy Science

Efficient hydrolysis of cellulosic biomass into free sugars for the production of bioethanol would allow utilization of an abundant and renewable natural resource. However, complex microcrystalline cellulose in biomass resists digestion. A preferred method to deconstruct cellulose is using enzyme cocktails, but the presence of multiple enzymes with synergistic outcomes for this process complicates direct biochemical analysis as a reliable indicator of deconstruction. Methods to detect release of free sugars rather than direct measurement of enzymatic activity are available but are time-consuming, and do not reflect the production of metabolic inhibitors of microbial growth which may interfere with the subsequent …

Lutein Exposure, In Ovo Or In The Diet, Reduces Parameters Of Inflammation In The Liver And Spleen Laying-Type Chicks (Gallus Gallus Domesticus), L.S. Meriwether, B. D. Humphrey, D. G. Peterson, K. C. Klasing, E. A. Koutsos

Animal Science

These trials examined whether the demonstrated effects of embryonic and dietary carotenoid exposure on the inflammatory immune response in fast growing chickens also occur in slow growing chickens. The systemic and local inflammatory responses of chicks were examined in two experiments with two in ovo lutein levels (C+, carotenoid replete; or C−, carotenoid-deplete), two dietary lutein levels (0 or 40 mg lutein/kg diet), and two inflammatory challenges [no exposure or lipopolysaccharide (LPS)-vaccinated]. At 24 h after LPS vaccination, spleen weight was not affected by diet or in ovo lutein, but liver weight increased from C+ eggs (p < 0.01), and in LPS-vaccinated chicks fed 0 mg lutein (p < 0.05), but not in chicks fed 40 mg lutein. Plasma carotenoids and liver carotenoids were reduced post-LPS (p < 0.05). Splenic IL-6 mRNA abundance was the greatest post-LPS in C− chicks fed 40 mg lutein vs. C+ chicks fed 40 mg lutein (p < 0.05). Hepatic IL-6, iNOS and TGFβ and splenic iNOS and TGFβ were not …