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Item A PM10 emission factor for free stall dairies(Texas A&M University, 2006-08-16) Goodrich, Lee BarryAmbient concentration measurements of total suspended particulate (TSP) were made at a commercial dairy in central Texas during the summers of 2002 and 2003. The facility consisted of both open pen housing and free-stall structures to accommodate approximately 1840 head of milking cattle. The field sampling results were used in the EPA approved dispersion model Industrial Source Complex Short Term version 3 (ISCST-v3) to estimate emission fluxes and ultimately a seasonally corrected emission factor for a free-stall dairy. Ambient measurements of TSP concentrations for sampling periods ranging from 2 to 6 hours were recorded during the summer of 2002. The mean upwind concentration was 115??g/m3 with a maximum of 231??g/m3 and a minimum of 41.4??g/m3. The mean net downwind TSP concentration was 134??g/m3 with a maximum of 491??g/m3 and a minimum of 14??g/m3. Field sampling at this same dairy in the summer of 2003 yielded significantly more 2 to 6 hour TSP concentration measurements. The mean upwind TSP concentration was 76??g/m3 with a maximum concentration of 154??g/m3. The mean net downwind TSP concentration was 118??g/m3 with a maximum of 392??g/m3 and a minimum of 30??g/m3. The particle size distributions (PSD) of the PM on the downwind TSP filters was determined using the Coulter Counter Multisizer. The results of this process was a representative dairy PM PSD with 28% of TSP emissions being PM10. The reported PM10 24-hour emission factors were 4.7 kg/1000hd/day for the free-stall areas of the facility and 11.7 kg/1000hd/day for the open pen areas of the dairy. These emission factors were uncorrected for rainfall events. Corrections for seasonal dust suppression events were made for the San Joaquin Valley of California and the panhandle region of Texas. Using historical rainfall and ET data for central California, the seasonally corrected PM10 emission factor is 3.6kg/1000hd/day for the free-stalls, and 8.7kg/1000hd/day for the open pens. For Texas, the seasonally corrected emission factor is 3.7kg/1000hd/day for the free-stall areas and 9.2kg/1000hd/day for the open lot areas.Item Development of an ammonia emission protocol and preliminary emission factor for a central Texas dairy(Texas A&M University, 2004-09-30) Rose, Adam JosephA protocol was developed to measure ammonia emission concentrations from dairies using an isolation flux chamber. A hybrid dairy in Comanche county, Texas, was measured for one week each during August 2002 and January 2003. Sixty total ammonia samples were taken from the free stall barn, open lot, mixing tank, separated solids, compost, and two lagoons using the developed protocol. The ammonia concentration measurements were made using a chemiluminescence analyzer located inside a mobile laboratory. From the emission concentrations recorded, it was estimated that 9.68 metric tons of ammonia were produced from this dairy per year. An emission factor of 13.34 ? 28.80 kilograms per day per thousand head of cattle (kg/day/1000 head) was estimated for this dairy (?95% confidence intervals) during summer conditions. For winter conditions the emission factor was 12.05 ? 12.89 kg/day/1000 head. The 11% difference of the emission factors from summer to winter conditions was predominantly from the change in ambient and control volume temperatures (a mean difference of approximately 25 degrees Celsius), differences in source temperatures, and seasonal variability in husbandry. The adsorption of ammonia onto different polymer tubing used in pollutant stream conveyance was researched for possible systematic losses. Teflon and low density polyethylene (LDPE) were tested for ammonia losses with treatments of: temperature, length, and inlet concentration. Inlet concentration and temperature were significant factors used to describe ammonia adsorption for Teflon, whereas LDPE was also affected by tubing length. These factors were used to create a model to correct the summer dairy measurements for ammonia losses, resulting in an emission factor increase of 8.3% over the original value obtained from the flux chamber. A nitrogen mass balance was performed to estimate the amount of nitrogen available for ammonia formation as excreted - 177.5 kilograms per year per animal (wet basis). The amount of ammonia excreted per year was also estimated to be 26.63 kilograms per year. The measured ammonia emitted from the dairy was five times less than the ammonia excreted and thirty-six times less than the total nitrogen excreted.Item Genomic Differences Between Highly Fertile and Sub-Fertile Holstein Dairy Heifers(2012-07-16) Navarrette, Ashley ElizabethInfertility in dairy cattle remains a major economic loss to dairy producers. Identifying dairy cattle with superior genetic potential for improved fertility would increase dairy farm profitability. Dairy heifers were classified into two groups based upon services per conception (SPC); those animals with a single SPC were determined to be highly fertile and animals with greater than or equal to 4 SPC were classified as sub-fertile. Whole genome association analysis was performed on 20 individual heifers from each group utilizing a 777K highly density (HD) single nucleotide polymorphism (SNP) chip. Genomic data were evaluated utilizing PLINK, a whole genome association analysis toolset, and 570,620 SNP were available for analysis with a total of 39 samples being analyzed. Forty-four SNP were determined to be associated with fertility classification (P <= 0.00001) and were located on Bos taurus chromosome (BTA) 2, 4, 9, 19, and 26. The SNP and ranges between SNP were analyzed using BLAST-Like Alignment Tool (BLAT); SNP were associated with 5 candidate genes for reproduction. The SNP on BTA 2 were located within the region coding for the non-imprinted Prader-Willi/Angelman syndrome 2 (NIPA2) gene, which is involved in gestational magnesium transport. Also on BTA 2, SNP were identified within the region encoding for cytoplasmic fragile X mental retardation 1 (FMR1) interaction protein 1 (CYFIP1). The CYFIP1 gene is involved with the functionality of FMR1 and has been linked to premature ovarian failure in humans. Additionally, 3 SNP on BTA 9 were located near monofunctional C1-tetrahydrofolate synthase (MTHFD1L), which has been linked to neural tube defects during gestation in humans A difference in allele frequency was observed between the two groups for SNP located on BTA19 in proximity to two genes, zinc finger 18 (ZNF18) and mitogen activated protein kinase 4 (MAP2K4). The ZNF18 motif and MAP2K4 were found to be involved in heart development of the early embryo and associated with toll-like receptors (TLR) involved in gonadotropin releasing hormone (GnRH) signaling, respectively. The involvement of one or all of these genes may further explain reduced fertility in dairy cattle.Item National Beef Quality Audit - 2011: Survey of Instrument Grading Assessments of Beef Carcass Characteristics(2012-11-16) Gray, Gatlan 1989-The instrument grading assessments for the NBQA-2011 evaluated seasonal trends of beef carcass quality and yield attributes over the course of the year. One week of instrument grading data?HCW, gender, USDA QG, and YG factors?were collected every other month (n = 2,427,074 carcasses) over a 13-month period (November 2010 through November 2011) from four beef processing corporations, encompassing 17 federally inspected beef processing facilities, to create an overview of carcass quality and yield attributes and trends from carcasses representing approximately 8.5% of the U.S. fed steer and heifer population. Mean yield traits were: YG (2.86), HCW (371.3 kg), FT (1.19 cm.), and LM area (88.39 cm^2). The YG distribution was YG 1 (15.7%), YG 2 (41.0%), YG 3 (33.8%), YG 4 (8.5%), and YG 5 (0.9%). Distribution of HCW was <272.2 kg (1.6%), 272.2 kg to 453.6 kg (95.1%), ?453.6 kg (3.3%). Monthly HCW means were: November 2010 (381.3 kg), January 2011 (375.9 kg), March 2011 (366.2 kg), May 2011 (357.9 kg), July 2011 (372.54 kg), September 2011 (376.1 kg), and November 2011 (373.5 kg). The mean FT for each month was November 2010 (1.30 cm), January 2011 (1.22 cm), March 2011 (1.17 cm), May 2011 (1.12 cm), July 2011 (1.19 cm), September 2011 (1.22 cm), and November 2011 (1.22 cm). The mean marbling score was Small49. USDA QG distribution was Prime (2.7%), Top Choice (22.9%), Commodity Choice (38.6%), and Select (31.5%). Interestingly, from November to May, seasonal decreases (P < 0.001) in HCW and FT were accompanied by increases (P < 0.001) in marbling. These data present the opportunity to further investigate the entire array of factors that determine the value of beef. Datasets utilizing the online collection of electronic data will likely be more commonly used when evaluating the U.S. fed steer and heifer population in future studies. These data indicate the wide array of carcasses produced by the beef cattle industry, and how the frequency of both YG and QG traits change from month-to-month.Item Non-Reacting Flow Characteristics and Emissions Reduction on Blends of Coal and Dairy Biomass in 30 kW_(t) Low NO_(x) Down-Fired Furnace(2014-08-07) Tiyawongsakul, TiyawutRecently, coal-fired power plants have considered either to retire themselves or to use natural gas as the main energy source instead of coal due to more stringent air pollution regulations for nitrogen oxides (NO_(x)), mercury (Hg) and more recently the required CO_(2) reduction of 30% by 2030. Clean coal technology must be continuously developed in order to prevent people from losing their jobs and to decrease the negative impacts of firing coal on environment. The present research focuses on NO_(x) emissions which arise mainly due to oxidation of fuel-bound nitrogen using low NO_(x) burner (LNB) when fired with Wyoming Powder River Basin coal (PRB) and blends of coal and dairy biomass (DB). The DB was selected as co-fired fuel for possible elimination of DB from dairy feedlots which result in land, air and water pollution if not properly disposed of. LNB adopts staged air introduction in order to limit the availability of oxygen when nitrogen from fuel is released. To achieve the objective, the mixing patterns between fuel particle and air were predicted using non-reacting flow (NRF) simulation inside the cylindrical combustion chamber. The effects of varying burner parameters, fuel particle sizes, main burner equivalence ratios (ER_(mb)) and overall equivalence ratios (ER_(oa)) on mixing characteristics were investigated. Then, the LNB components were modified based on the results from NRF simulation. The modified main burner is a partially premixed swirl burner (fuel mixes with the primary air inside the fuel/primary air nozzle, and the secondary air is swirled by the straight-vane swirler) whose swirl angle and secondary air swirl number are 59? and 1.42 respectively. The circular over-fire air (OFA) nozzles are located 484 mm below the main burner exit, and the OFA is injected into the combustion chamber in the radial direction. The fuels used in the research were: 1) pure PRB and 2) the fuel blend of PRB and DB with the PRB-to-DB ratio of 90 to 10 on mass basis (90-10 PRB-DB blend). Fuel characteristics were first obtained, and empirical chemical formulae were deduced. The CO_(2), O_(2) and NO were measured as a function of ER_(oa) and ER_(mb) (ER_(mb) based on air flow without inclusion of OFA). The gas analyses were used to obtain the burnt fraction, respiratory quotient (RQ, = CO_(2) moles produced/O_(2) moles consumed) and equivalence ratio which is then checked against measured values. Uncertainty analyses were also performed. The optimum conditions for minimum NO_(x) emission that pass the EPA limit (210 g/GJ) were obtained as follows. With ER_(oa) = 0.95, firing pure PRB produced NO_(x) 220 g/GJ without OFA, and 179 g/GJ with OFA (ER_(mb) = 1.10) which is about 18.6 % reduction. Under same conditions, the co-firing of 90-10 PRB-DB blend decreased NO_(x) by 3.6% without OFA, and 22.2% with OFA (ER_(mb) = 1.10) compared to firing pure PRB at ER_(oa) = 0.95 without OFA. Furthermore, co-firing 90-10 PRB-DB blend with OFA at ER_(mb) = 1.10 and ER_(oa) = 0.95 (excess air 5.26%) emitted NO_(x) approximately 171 g/GJ whilst firing pure PRB without OFA at ER_(oa) = 0.85 (excess air 17.65%) emitted NO_(x) approximately 330 g/GJ which is 48% reduction and less than 210 g/GJ (the current EPA limit). This reduction could benefit 500-MWt power plants approximately $113,500 per year in case the efficiency of power plants is 35% and NO_(x) are traded at $15.89 per short ton.Item Prevalence and spatial distribution of antibodies to Salmonella enterica serovar Typhimurium O antigens in bulk milk from Texas dairy herds.(Texas A&M University, 2004-09-30) Graham, Sherry LynnThe purpose of this study was to describe the herd antibody status to Salmonella Typhimurium as estimated from co-mingled milk samples and to describe the resulting geographical patterns found in Texas dairy herds. Bulk tank milk samples were collected from 852 Grade A dairies throughout Texas during the summer of 2001. An indirect enzyme-linked immunosorbent assay (ELISA) using S. Typhimurium lipopolysaccharide was performed with signal to noise ratios calculated for each sample. The ELISA ratio was used in fitting a theoretical variogram and kriging was used to develop a predicted surface for these ratios in Texas. A spatial process with areas of higher risk located in the panhandle and near Waller County was apparent. Lower risk areas included Atascosa, Cooke, Collin, Titus, Comanche and Cherokee Counties. Subsets representing large dairy sheds in northeast Texas, the Erath County area, and the Hopkins County area were also evaluated individually. Each result illustrated a spatial process with areas of low and high ELISA ratio predictions. Cluster analysis was performed for the entire state with cases defined as herds having milk ELISA ratios greater than or equal to 1.8. Using this cutoff, the prevalence of herds with positive bulk tank milk ELISAs was 4.3%. Significant clustering of cases was demonstrated by the Cuzick and Edward's test. The spatial scan statistic then identified the two most likely clusters located in and near the Texas Panhandle. This study demonstrated that the distribution of S. Typhimurium antibodies in bulk tank milk in Texas is describable by a spatial process. Knowledge of this process will help elucidate geospatial influences on the presence of S. Typhimurium in dairy herds and enhance our understanding of the epidemiology of salmonellosis.