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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Regulation and Expression of Nanog, Oct4, and Sox2 in the Bovine Blastocyst following Somatic Cell Nuclear Transfer

Hall, Justin Scott 01 May 2013 (has links)
A live birth from a somatic cell nuclear transfer (SCNT) embryo represents a small percentage of donor cells that survived the reprogramming gauntlet. The inability to reprogram histone modifications in the donor cell line could add to the reprogramming deficiencies associated with SCNT. The effects of two histone modifications associated with transcriptional activation (H3K4m3 and H4K16ac) and two histone modifications associated with repressing transcription (H3K9m2 and H3K27me3) were evaluated in the context of their association to three genes known to contribute to maintaining totipotency: Nanog, Oct4, and Sox2. A µChIP assay was utilized using antibodies specific for each histone modification followed by real time PCR (qPCR) analysis to quantify the percentage of each gene associated with each particular histone modification. Gene expression analysis was followed by immunofluorescence and protein analysis. Results of these analyses suggest that gene association to certain histone modifications did not accurately predict gene expression in bovine blastocyst embryos. Of the three genes studied, only Oct4 expression differed significantly between in vitro fertilized (IVF; control) and SCNT blastocysts. Protein levels detected through immunofluorescence correlated directly with the gene expression analysis. Nanog and Sox2 expression profiles of IVF and SCNT bovine blastocysts are similar, yet the histone modification profiles associated with all three genes differ significantly. Altered expression levels in developmentally important genes will likely result in abnormal activity of the associated cellular pathway. Aberrant histone modifications, along with abnormal Oct4 expression, may contribute to the low percentage of SCNT embryos that result in live offspring.
142

Peromyscus Populations as Related to Seasons and Vefetative Types at the Hardware Ranch, Cache County, Utah

Turner, George Cleveland, Jr. 01 May 1950 (has links)
Members of the genus Peromyscus, White-footed Mice, are known to occur in nearly all habitats of North America. Because of their numerical abundance and widespread distribution, these mice are extensively used in the study of the dynamics of animal populations. Thus, information perteining to the local distruibution and activities of these mice is of value to the more comprehensive studies that are being carried out in the field of zoological research.
143

Evaluation of Casein Hydrolysate as an Alternative Dry-Off Treatment and Milk Quality Management Tool in Dairy Cows

Britten, Justine Elena 01 May 2019 (has links)
Mastitis, an infection of the mammary gland, is the most common and expensive animal health problem for the dairy industry and affects every dairy farm to some degree. This disease complex is painful for dairy cows, increases the on-farm use of antibiotics, presents a threat to milk quality and is a waste of time, money and milk production. Each year, the dairy industry loses as much as a billion dollars to mastitis. Many cows will experience mastitis at least once during a lactation cycle and some animals will develop recurring mastitis episodes in a single mammary quarter. These mastitic quarters can be difficult to manage during the lactation cycle. Cessation of production in the quarter while continuing to milk the other three can be a beneficial management decision in this scenario. However, the current methods available for cessation of lactation in a single quarter are limited. This study investigated the use of casein hydrolysate as a non-antibiotic option for causing cessation of lactation in a quarter. From this preliminary study we were able to apply our results to another aspect of mastitis prevention, which is the routine use of intramammary antibiotics at the end of the lactation cycle. This management practice is known as dry treatment and is a standard practice in the dairy industry with many years of proven efficacy against clearing infections present at the end of the lactation cycle. Increasing pressure from consumers to decrease antibiotic use in food production animals has caused this practice to come under scrutiny. This secondary study investigated the use of casein hydrolysates as a nonantibiotic alternative to standard antibiotic dry cow treatment. Overall, these studies demonstrated that casein hydrolysate has some efficacy in inducing mammary involution of a single quarter mid-lactation and also potentially as an alternative dry cow treatment. None of the animals treated in these studies displayed any symptoms of pain or discomfort, and all treated quarters resumed milk production after the next calving. Additionally, all antimicrobial milk tests on treated animals were negative. Casein hydrolysates may be a useful management tool for milk quality and animal health within the dairy industry.
144

A Computerized Performance Record Keeping System for Beef Cattle in Utah

Pierce, John J. 01 May 1973 (has links)
A computer program was developed at Utah State University (USU) to aid in obtaining a more complete individual performance record keeping system for beef cattle in Utah. Some computer programs for beef cattle records presently exist but a program was needed that was readily available to the USU animal science extension and resident staff. The program was written in FORTRAN for use on the Burrogh 6700 computer located at the Utah State University Computer Center. It was designed to read input data for individual animals, perform various calculations (i. e. days of age, adjusted weaning weight and weaning weight ratio), print out the input data and results of the calculations for each animal as well as the average adjusted weight for each sex group (heifer, bull, steer). The computer program will manipulate weights in either the English or metric system and will convert weights from the English to metric system if desired. A unique feature of the program is the ranking of animals from highest to lowest based on the weaning weight ratio with accompanying animal number. The records can be evaluated to identify potential animals to use as replacements and those to be culled. The input data are collected on the ranch by a cooperative arrangement between the ranch operator and the USU Extension Staff. The ranch operator collects the preliminary data such as: birth date, tag number, tattoo number, dam, age of dam, and sire, and records it on the beef cattle performance input record. The extension specialist weights, gives a conformation score and records the information for each calf on the input record. The beef cattle performance input record is arranged in the same order as the data card is key punched thus facilitating the punching of the data cards. The staff can change from using the desk calculator to the use of the computer to improve efficiency and flexibility output as well as having more time available to spend with the public teaching that maintaining accurate records can help improve their herds for production and for inventory control. This can help the beef cattle industry to improve quality and type of beef animal produced in Utah and should improve the potential efficiency and profit. The rancher can transfer his records, with minor modifications, to one of the existing national computer programming organizations if desired. This computer program with or without modification has application for current research and university teaching. The computer program was designated for use with beef cattle, but could be modified to use for any class of livestock. This program is not an end in itself but is a foundation from which to build an improved record keeping system in Utah which could improve the production and quality of the beef cattle industry.
145

In Vitro and In Vivo Comparison of the Pathogenicity of Four Influenza Virus Strains

Hurst, Brett L. 01 May 2012 (has links)
Influenza viruses cause between 3 and 5 million cases of respiratory infection each year and are responsible for between 250 and 500 thousand deaths. There are principally two avenues for the treatment and prevention of influenza. They are vaccination and antiviral regimens. Prevention of infection is largely accomplished through vaccination. While vaccines remain the preferred method for controlling the spread of influenza, treatment with antiviral drugs is important for treatment of severe infections that are caused by viruses that are different from the vaccination strains. The two major classes of antiviral drugs for influenza treatment are the adamantanes and the neuraminidase inhibitors. While most viruses have become resistant to the adamantanes, the neuraminidase inhibitors remain the primary choice for treatment of infections. Oseltamivir is the most important of the neuraminidase inhibitors. Data from an experiment run at Utah State University displayed a characteristic that is reflected in other published data. Oseltamivir, which has been shown to be effective against influenza virus strains in vitro, is unable to sufficiently protect mice from lethal infections. The focus of the present research was to identify viral differences that might explain for this discrepancy. Four viral strains were chosen that display differing susceptibilities to oseltamivir in mice. The viruses used were Influenza A/Duck/MN/1525/81 (H5N1), A/Victoria/3/75 (H3N2), A/NWS/33 (H1N1) and A/California/04/2009 (Pandemic H1N1). Oseltamivir was unable to protect mice that were infected with the A/Duck/MN/1525/81 and A/Victoria/3/75 viruses. These two viruses, along with the A/NWS/33 and the A/California/04/2009 viruses, were compared in vitro using virus replication kinetics, neuraminidase inhibition assays, and antiviral assays in cell culture. The viruses were studied in vivo by comparing survival, weight loss, lung scores and weights, lung virus titers, complete blood counts, cytokine assays, and histopathology. A second in vivo experiment was run to determine the effects of oseltamivir on survival, weight loss, lung scores and weights, lung virus titers, and histopathology. The two in vivo experiments summarized in this study confirmed previous data since oseltamivir was unable to protect mice infected with the influenza A/Duck and A/Victoria viruses. Overall, the virus infections behaved remarkably similar. The most interesting difference was that the A/Duck/MN/1525/81 and A/Victoria/3/75 viruses were able to induce more severe histopathological damage in mouse lungs earlier in the infection. The ability to cause severe disease more quickly might explain why the A/Duck/MN/1525/81 and A/Victoria/3/75 viruses remain lethal, despite oseltamivir treatment.
146

Impact of Basal Diet on Obesity Phenotype of Recipient Mice Following Fecal Microbiome Transfer from Obese or Lean Human Donors

Rodriguez Jimenez, Daphne Michelle 01 August 2018 (has links)
The composition of the gut microbiome can be affected by environmental factors, such as diet. The Western dietary pattern is associated with microbiome dysbiosis and adverse health outcomes, including obesity and metabolic disorders. The objective of this study was to examine the effect of gut microbiota from lean or obese human donors on metabolism and weight gain in recipient mice fed one of three basal diets: 1) the standard AIN93G diet, which promotes rodent health; 2) the total Western diet (TWD), which mimics the American dietary pattern and promotes inflammation-associated colorectal carcinogenesis; and 3) a 45% high fat diet-induced obesity (DIO) diet, which promotes excessive weight gain and symptoms of metabolic syndrome. We hypothesized that fecal microbiome transfer (FMT)from obese human donors would lead to an obese phenotype with symptoms of metabolic syndrome in recipient mice, and that consumption of TWD or DIO diets would further exacerbate the metabolic syndrome phenotype. The experiment design consisted of two main factors: body type of the human donor (obese or lean) and experimental diet (AIN, DIO or TWD), which was fed to mice for 22 weeks. Prior to FMT, the resident gut microbiome in mice was depleted using an established broad spectrum antibiotic/antifugal oral dosing regimen. Interestingly, human donor body type did not significantly affect final body weight or body composition in recipient
147

The Use of Lactic Acid in the Manufacture of Cheddar Cheese from Milk Containing an Antibiotic

George, Elmer, Jr. 01 May 1955 (has links)
The manufacture of cheddar cheese is greatly dependent on bacterial growth for acid production. The quality of cheese depends upon the type and extent of microbial activity. An important function of the lactic fermenting bacteria is the production of acid resulting from cellular metabolism. If little or no acid is production of acid resulting from cellular metabolism. If little or no acid is produced the resulting cheese will have an inferior body, flavor, and texture and may even cause the cheese to be used as grinders. The major causes for inhibited lactic bacterial growth are poor starter handling procedures, antibiotic in mild coming from cows treated for mastitis, quaternary ammonium compounds used in plant sanitation, and bacteriophage. The occurrence of bacteriophage contamination and the increased use of quaternary ammonium compounds and antibiotics have caused a serious problem in cheese manufacturing. Purpose of project. The purpose of this project is to determine if cheddar cheese, comparable to normal cheese, can be made from slow or non-acid milk with the use of added lactic acid. Lactic acid will be used for the purpose of substituting for the acid that is normally produced by bacterial metabolism in the manufacture of cheddar cheese.
148

A Comparison of Three Estrous Detection Management Schemes for Dairy Heifers

Lagerstedt, Ann 01 May 1990 (has links)
Heifers should represent the greatest genetic potential within a dairy herd. To maximize this potential, heifers must be inseminated to proven sires, a practice requiring management changes on many dairies. Holstein heifers (n=115) were allotted to one of three groups to compare alternatives to daily estrous detection that may facilitate the management of a program of artificial insemination for heifers. Group 1 heifers (Controls) received no treatment but were observed twice daily for signs of estrus. Group 2 heifers (2X-PGF) were synchronized with two injections of prostaglandin F2 alpha given 11 days apart and observed for estrus. Group 3 heifers (MGA+PGF) were synchronized with 9 days of melengestrol acetate feeding and an injection of prostaglandin F2 alpha 14 days after the last feeding and observed for estrus. Comparisons were made on the effectiveness of each treatment in estrous response and pregnancy rates and on the management requirements and economics associated with each program. Estrous response was significantly higher for the 2X-PGF group, while synchronized pregnancy and first-service conception rates did not differ. On an annual basis, the MGA+PGF group was calculated to require three-quarters of the labor input as compared to the 2X-PGF group and less than a fifth of the labor required for the Control group. A program of daily estrous detection was calculated to have an economic advantage over synchronization the frequency estrous synchronization programs was scheduled four times per year. was increased to six times per when When year, synchronization had a slight economic advantage over daily estrous detection when animal numbers were low and labor costs were high. The economic advantage of daily estrous detection is reduced when synchronization is performed more frequently throughout the year.
149

Analysis of Single Nucleotide Polymorphism Panels for Bovine DNA Identification

Blanchard, Kimberly A. 01 May 2013 (has links)
Single nucleotide polymorphisms (SNPs) are single base-pair variations that exist between individuals. There are approximately a million or more SNPs located throughout the genome of each individual animal. Therefore, by taking advantage of these unique polymorphisms, SNPs can be used to resolve questions of unknown parentage in the livestock industry. Currently a panel of 88 SNPs, obtained from a panel of 121 SNPs originally created by USDA-MARC, is commercially available from Fluidigm®. The objective of this study was to determine whether the number of SNPs from the 88-SNP marker panel could be reduced to form a smaller, more cost-efficient parentage-testing SNP panel. A smaller panel would benefit farmers and researchers alike in reducing the time spent in running and analyzing the test, as well as reducing the overall cost for the procedure. Genotype data from over 3000 cattle samples containing offspring and potential parents were examined using two parentage calling software packages. Parentage assessment was analyzed using nine SNP panels of varying size. It was determined that a panel of 71 SNPs, chosen from the original 88 SNPs, was the minimum number required to maintain statistical accuracy and reliability.
150

Production and Intake Responses of Dairy Cows Fed Four Levels of Malic Acid

Martinez Alferez, Juan Carlos 01 May 1978 (has links)
Thirty-two lactating cows were assigned at random to four treatments of malic acid to determine if these levels had an effect on milk production, milk composition, feed intake, and efficiency of feed utilization. Malic acid allotment for each treatment consisted of 1) 15.4, 2) 11.6, 3) 7.7, and 4) 0 grams of malic acid fed per kilogram of concentrate. Concentrate was fed according to production at a rate of one kilogram per two kilograms of milk in excess of 9.1 kilograms of milk per cow daily. Alfalfa hay was fed free choice and corn silage at a rate of 11.4 kilograms daily. The cows were on the trial for 8 weeks. Intake of concentrates, silage, dry matter, and digestible energy was highest for cows receiving the 11.6 g level of malic acid. These intakes were significantly higher than for the 7.7 g level but not for the other treatments. However, cows on the 7.7 g level consumed only slightly less feed than control cows. There was no significant effect on hay or crude protein intake. Production of total milk, fat corrected milk, and milk fat was significantly higher for cows receiving the 11.6 g level of malic acid than from the 7.7 g level or control cows. Production of protein solids-not-fat was significantly higher for the 11.6 g level than from the 7.7 g level and approached this level of significance when the 11.6 g level was compared to the controls. Cows receiving the 11.6 g level of malic acid were significantly more efficient in converting dry matter or digestible energy from feed into milk than were the controls. Intakes and production of cows on the 15.4 g level was slightly less than for the 11.6 g level.

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