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Evaluation Of Anthelmintic Therapies In A Fall Calving Beef Cowherd, Laine Zammit May 2020

Evaluation Of Anthelmintic Therapies In A Fall Calving Beef Cowherd, Laine Zammit

Graduate Theses and Dissertations

Internal parasitism inevitability prompts economic loss in beef cattle production by decreasing growth performance and reproductive traits. Today, the most widely used class of anthelmintic used to treat parasitism, is the macrocyclic lactone. Many studies have conflicting results on the efficacy of macrocyclic lactones (ML) efficacy against internal parasitism. The objective of this study was to evaluate the effectiveness of moxidectin and eprinomectin, two of the MLs, on cow performance. Multiparous fall calving, crossbred beef cows (n = 106) were allocated randomly to 1 of 3 anthelmintic treatments: 1) Negative control (CON), in which cows did not receive an anthelmintic, …


Associations Among Beef Cattle Genotypes, Neospora Caninum Infection, And Reproductive Performance, Ryan James Page May 2020

Associations Among Beef Cattle Genotypes, Neospora Caninum Infection, And Reproductive Performance, Ryan James Page

Graduate Theses and Dissertations

Reproductive performance is crucial for sustained financial success in the beef cattle industry. This dissertation includes a population study that quantified the incidence of Neospora caninum infections in the central region of the United States and tested its relationship with reproductive performance in beef cattle. Trial one of that study concluded that 6.9% of open, replacement heifers (n = 1306) tested seropositive. The second trial in that project found that 9.6% of the breeding age females (n = 500) tested were seropositive for Neospora caninum; and that state in which the cattle lived and age impacted (P < 0.05) infection rate. Breed composition, number of farm dogs on the ranch, and use of total mixed rations were not associated (P > 0.1) with seropositive …


Effects Of Lasalocid And Energy Supplementation On Forage Intake, Energy Metabolism, And Performance Of Cattle Grazing Wheat Pasture, Autumn Tayler Pickett May 2020

Effects Of Lasalocid And Energy Supplementation On Forage Intake, Energy Metabolism, And Performance Of Cattle Grazing Wheat Pasture, Autumn Tayler Pickett

Graduate Theses and Dissertations

Cattle grazing wheat pasture have the potential to gain BW exceptionally well, but excessive nitrogen intake results in increased excretion and increased greenhouse gas (GHG) emissions. Supplemental concentrates with the addition of an ionophore given to ruminants grazing wheat is a potential practice for producers to increase nitrogen efficiency while decreasing GHG emissions. Therefore, the objective of this experiment was to quantify the effects of energy (2.95 kg/d) and lasalocid (200 mg/hd/d) supplementation on nutrient intake, energy metabolism, respiratory gas fluxes, and performance of grazing cattle. Methane emissions were not affected (P = 0.58) by treatment, hence methane intensity (P …


Establishing An Ideal Inclusion Rate Of Fermented Soybean Meal And Sodium Butyrate On Growth Performance, Complete Blood Cell Count, And Nutrient Utilization In Nursery Pigs, Kristopher A. Bottoms Dec 2019

Establishing An Ideal Inclusion Rate Of Fermented Soybean Meal And Sodium Butyrate On Growth Performance, Complete Blood Cell Count, And Nutrient Utilization In Nursery Pigs, Kristopher A. Bottoms

Graduate Theses and Dissertations

To evaluate increasing levels of sodium butyrate (SB) in nursery diets on growth performance (Experiment 1 & 2), complete blood cell count (Experiment 2), and the optimal level of fermented soybean meal for maximum performance in weanling pigs (Experiment 3), weaned pigs were blocked with initial body weight (BW) and allotted to dietary treatments. Treatments were: 1) Control (C) moderately complex corn-soybean-meal based supplemented with 0.05% benzoic acid (BA), but devoid of SB; C diet supplemented with 0.05%, 0.10%, or 0.15% SB (Experiment 1). Treatments in experiment 2 consisted of 1) a moderately complex corn-soybean-meal based diet devoid of SB …


Estimation Of Genetic Components Related To Infectious Bovine Keratoconjunctivitis Susceptibility In Angus And Angus Derived Cattle Produced In The Southern United States, Eric Oxford Dec 2019

Estimation Of Genetic Components Related To Infectious Bovine Keratoconjunctivitis Susceptibility In Angus And Angus Derived Cattle Produced In The Southern United States, Eric Oxford

Graduate Theses and Dissertations

The economic impact of infectious bovine keratoconjunctivitis (IBK) has been documented in many parts of the world. Many researchers have observed that prevention of this disease is very difficult given current methodologies. This is primarily due to the multifactorial nature of this disease. The objective of this dissertation was to determine the impact of IBK on calf performance and estimate genetic parameters, heritability and estimated breeding values for IBK susceptibility. Data were analyzed using PROC GLIMMIX of SAS; while genetic parameters were estimated using a linear animal model for both single- and two-traits through MTDFREML. Additional evaluations calculated heritability using …


Characterization Of The Swine Gut Microbiome Dynamics, Culturomics And Probiotics, Xiaofan Wang Aug 2019

Characterization Of The Swine Gut Microbiome Dynamics, Culturomics And Probiotics, Xiaofan Wang

Graduate Theses and Dissertations

The gastrointestinal tract is a critical place where the immune system concentrates many of its protective functions. It exerts both physical and biochemical defenses against invading foodborne pathogens and other hazards. In pigs, the gut microbiota community assembled postnatal plays a very important role in the development of multiple physiologic aspects, such as development of the gastrointestinal tract, nutrient exchange, immune defense against foreign pathogens and growth performance. Microbiome-host communication changes with age. Despite recent advances in understanding the swine gut microbiome at different growth stages, a comprehensive longitudinal study of the lifelong dynamics of the swine gut microbiome is …


The Impacts Of Administering Metabolites Of Saccharomyces Cerevisiae On Broiler Performance, Yields And Salmonella Content Of Component Portions, Bill Douglas Potter May 2019

The Impacts Of Administering Metabolites Of Saccharomyces Cerevisiae On Broiler Performance, Yields And Salmonella Content Of Component Portions, Bill Douglas Potter

Graduate Theses and Dissertations

The impacts of using health-promoting Saccharomyces cerevisiae fermentation metabolites in poultry production and processing can be measured in respect to multiple measures of success. Traditionally this yeast-based compound has been administered to poultry, livestock, poultry, and other species to improve animal performance and production volume output. In addition, Saccharomyces cerevisiae fermentation metabolites have also been shown in more recent research to reduce colonization of pathogenic bacteria in the host organism’s gastro-intestinal tract. In this dissertation, the impacts of administering a functional ingredient containing Saccharomyces cerevisiae metabolites on broiler performance measures and pathogen reduction were measured. One of the studies in …


Study Of Three Potential Variables That May Impact The Maximum Shear Force And Shear Variation During The Growth And Transport Of Mixed Sex Broilers Grown In Commercial Poultry Houses, Mark Christie Dec 2018

Study Of Three Potential Variables That May Impact The Maximum Shear Force And Shear Variation During The Growth And Transport Of Mixed Sex Broilers Grown In Commercial Poultry Houses, Mark Christie

Graduate Theses and Dissertations

Temperature conditions during the transportation to the processing facility of commercial broilers have a direct impact on the meat texture, specifically maximum shear force and shear variation of cooked breast meat. Analysis of a calendar year of flock data (N=346), reveals that the largest impact of transport conditions, specifically temperature, is on the standard deviation of the flocks range of cooked shear values. The optimal transport temperature that yields broiler breast meat with average flock minimum shear and standard deviation values is approximately 60°F. The shear values for flocks at or near 60°F are on average 1 kg less than …


Optimizing Methods To Determine Metabolizable Energy Values Of Feed Ingredients For Broilers, Skyler P. West Dec 2018

Optimizing Methods To Determine Metabolizable Energy Values Of Feed Ingredients For Broilers, Skyler P. West

Graduate Theses and Dissertations

Determination of metabolizable energy (ME) and amino acid (AA) digestibility values of single feed indigents continues to be two of the most important aspects for successful least-cost poultry feed formulation. It would be advantageous if a common diet type could be utilized to determine both ME and AA digestibility values of feed ingredients within a single assay. Two experiments were conducted to evaluate the effect of basal diet type and excreta collection method on the ME value of single feed ingredients determined in broiler chicks using the regression method. In experiment 1, the objective was to investigate the influence of …


Efficacy Of Natural Compounds With Novel Carrier Systems For Controlling Campylobacter Jejuni In Post-Harvest Poultry, Sandip Shrestha Dec 2018

Efficacy Of Natural Compounds With Novel Carrier Systems For Controlling Campylobacter Jejuni In Post-Harvest Poultry, Sandip Shrestha

Graduate Theses and Dissertations

Campylobacter jejuni, a leading cause of bacterial gastroenteritis worldwide, is strongly associated with the consumption and/or mishandling of raw contaminated poultry products. Thus, interventions aiming to reduce C. jejuni counts on poultry products could greatly reduce the incidence of human campylobacteriosis. In the first study, the efficacy of a generally recongnized as safe (GRAS) compound, carvacrol (CR; derived from oregano oil), as an antimicrobial wash treatment to reduce C. jejuni on chicken skin was evaluated. Three delivery systems of CR: suspension, emulsion and nanoemulsion were used. C. jejuni counts were reduced up to 4 log10 cfu/sample by 2% dose of …


The Use Of Probiotics To Control The Microbial Load Present In Commercial Broiler Chicken Hatch Cabinets As An Alternative To Formaldehyde Fumigation, Lucas Elzie Graham May 2017

The Use Of Probiotics To Control The Microbial Load Present In Commercial Broiler Chicken Hatch Cabinets As An Alternative To Formaldehyde Fumigation, Lucas Elzie Graham

Graduate Theses and Dissertations

Formaldehyde has been used for decades as a disinfectant in the poultry hatchery. Hatch cabinets are treated with formaldehyde to control the microbial bloom that occurs inside of the hatch cabinet as the hatch progresses. Even with formaldehyde being a known human carcinogen and the detriment that it has on living creatures millions of chicks are exposed to formaldehyde in the hatch cabinet. In these experiments we tested a lyophilized probiotic spray inside of the hatch cabinets from day nineteen to day twenty one to control the microbial bloom that occurs. Hatch cabinet environments were sampled in six experiments. Media …


In Ovo Evaluation Of Floramax-B11 On Marek's Disease Hvt Vaccine Protective Efficacy, Hatchability, Microbiota Composition, Morphometric Analysis, And Salmonella Enteritidis Infection In Broiler Chickens, Kyle Dean Teague May 2017

In Ovo Evaluation Of Floramax-B11 On Marek's Disease Hvt Vaccine Protective Efficacy, Hatchability, Microbiota Composition, Morphometric Analysis, And Salmonella Enteritidis Infection In Broiler Chickens, Kyle Dean Teague

Graduate Theses and Dissertations

It has previously been shown that effective probiotics can accelerate gut maturation and the development of a normal microflora in poultry. This results in increased resistance to enteric pathogens encountered by chicks early in life. Our objective in experiments 1 and 2 was to evaluate the effect of in ovo administration of FloraMax®-B11 (FM) on Marek’s disease (MD) herpesvirus of turkeys (HVT) vaccine protective efficacy. In Exp. 1, day 18 White Leghorn embryos were randomly distributed in four groups, 1) HVT vaccinated, no MDV challenge, 2) HVT + FM vaccinated, no MDV challenge, 3) HVT vaccinated, challenge with virulent MDV, …