The Tapered Element Oscillating Microbalance (TEOM) sampler is an EPA approved Federal Equivalent Method Sampler for measuring PM10 concentrations. The Center for Agricultural Air Quality Engineering and Science (CAAQES) owns two Rupprecht and Patashnick (R&P) Series1400a monitors. The R&P Series 1400a monitor uses the TEOM method to measure particulate matter (PM) concentrations and was approved by EPA in 1990 as an automated equivalent method PM10 sampler. Since its approval, many state air pollution regulatory agencies (SAPRAs) have located R&P Series 1400a monitors at community-oriented monitoring sites. Some SAPRAs have even located TEOM samplers at the property line of major sources to determine if the source is meeting its permit requirements for PMc emissions. This thesis presents the results of PM10 and TSP concentrations measured with TEOM and low-volume gravimetric samplers at two Texas cattle feedlots. The purpose of this research was to compare the performance of the R&P Series 1400a monitor to the low-volume gravimetric sampler when sampling PM from a feedlot. Furthermore, this research was conducted to avoid the inappropriate regulation of cattle feedlots that may occur in the future as a consequence of the TEOM sampler being used to measure PMc emissions. The results of this research demonstrate that relationship between the R&P Series 1400a monitor and the low-volume gravimetric sampler is linear. In general, it was observed that the TEOM sampler measured higher PM10 and TSP concentrations than the low-volume gravimetric sampler when sampling downwind from a cattle feedlot. The opposite results were observed when sampling was conducted upwind from the feedlot. The collected data demonstrates that the concentration difference between the two sampling methods is linearly dependent with the concentration intensity for the upwind sampling locations. This trend was shown to be statistically significant. Another linear relationship was observed between the concentration difference and the particle size (mass median diameter and geometric standard deviation) of the sampled dust. Although this trend was not statistically significant, it is believed that additional downwind concentration measurements would validate this relationship.

Transfer and shedding of a rifampicin-resistant strain of Escherichia coli (RREC) among cattle was studied in a research feedlot comprised of 30 pens of 11 or 12 yearling steers. On 3 separate occasions, 9,6 and 6 of the 12 steers in 3 different peripheral pens in the lot were orally inoculated with 1011 cells of an unmodified RREC isolate from bovine feces. Fecal swabs were preformed on all 360 steers in the feedlot immediately prior to and at approximately 5-week intervals thereafter. Following inoculation, fecal grab samples were collected daily from all 12 pen mates for up to 4 months. In all 3 trials, the inoculated steers each shed RREC within 24 h of inoculation. All 12 steers in each inoculated pen were positive for RREC within 48 h; all 36 steers shed RREC intermittently throughout the three sampling periods. Transfer to 4 steers in an adjacent pen was confirmed only during the first trial (3 steers shed once each on day 8, day 26 or day 40; the fourth shed on 6 occasions between days 8 and 40). Transfer to non-adjacent pens was not detected during any of the 3 trials. All recovered RREC isolates were compared to the inocula using LMX agar and fatty acid methyl ester (FAME) analysis. Additionally, select recovered isolates were subjected to carbon source utilization tests. The three inocula were further subjected to 16S rRNA sequence analysis, minimum inhibitory antibiotic concentration profiles and pulsed-field gel electrophoresis and were determined to be the same strain. It was observed with the exception of the pen floor, that the resistant strain did not move through the animal feedlot environment, as easily or pervasively as other studies suggested. The RREC did not persist in the feedlot environment beyond the 4-month trial period. Fecal contamination form the pen floor, animal-to-animal contact and the chute system may have facilitated transfer of the resistant strain between animals. Animal stress may have facilitated the pen-to-pen transfer observed during trial 1, as the inoculation was conducted within 1 week of the steers' arrival in the feedlot. / xii, 102 leaves : ill. ; 28 cm.

Thesis (MMedVet (Production Animal Studies)--University of Pretoria, 2007. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1963. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Orientador: André Mendes Jorge / Banca: Roberto de Oliveira Roça / Banca: José Roberto Sartori / Banca: Evaldo Antonio Lencioni Titto / Banca: Rubén Roberto Velazco Gutierrez / Resumo: O ultra-som é utilizado também como uma ferramenta para estimar a área de olho de lombo e a espessura de gordura subcutânea em animais de produção. Os trabalhos sobre o uso do ultra-som são direcionados aos bovinos, portanto é imprescindível estudar esta ferramenta na criação dos bubalinos. Foram utilizados 20 bubalinos, da raça Murrah, castrados, descornados, com idade média inicial de 15 meses. Submeteram-se os animais a quatro tratamentos, abatidos aos 75, 100, 125, 150 dias de confinamento. As medidas realizadas foram área de olho de lombo, espessura de gordura subcutânea do dorso (avaliadas entre a 12ª e 13ª costelas) e a espessura de gordura da garupa, mensuradas pelo ultra-som quando os búfalos atingiram o ponto de abate pelo período de confinamento e, na carcaça após o abate, através da. A área de olho de lombo, espessura de gordura do dorso e da garupa, realizadas pelo ultra-som e na carcaça, apresentaram efeito linear crescente (P<0,05). O ultra-som subestimou a área de olho de lombo da carcaça, sendo, a diferença entre as medidas -5,4cm2. A área de olho de lombo para 100kg de carcaça, no último abate foi 27,8cm2 e a espessura de gordura subcutânea do dorso 3,8mm. As correlações medidas pelo ultra-som e na carcaça foram 0,75 (P<0,05) para área de olho de lombo e 0,82 (P<0,05) para espessura de gordura subcutânea no dorso. As características de carcaça medidas por ultra-som, em bubalinos, apresentam boas correlações com as medidas realizadas na carcaça. / Abstract: The ultrasound is used too as estimate the ribeye and fat thickness. The works about the use of ultrasound are managed to cattle, therefore it is essential to study the use of this tool to raise buffaloes. Twenty castrated, hornless, Murrah buffaloes with average initial age of 15 months old. The buffaloes were separated in four groups that were slaughtered in 75, 100, 125, 150 days of feedlot. The measures were ribeye, back fat thickness (between 12ª and 13ª ribs) and fat thickness in rump, measured by the ultrasound when the buffaloes reached the slaughter point by the feedlot stages and in the carcass at the moment of slaughter. The ribeye, back fat thickness and fat thickness in rump presented linear increase effect (P<.05). The average difference between the ribeye in ultrasound and carcass was 5.4 cm2, we observe that the ultrasound underestimated the ribeye in carcass. The ribeye for 100kg of carcass, the last slaughter was 27.8 cmø and back fat thickness 3.8mm. The increase of fat thickness measure for days in feedlot in carcass and ultrasound was similar between back and rump. The correlations measured by the ultrasound and carcass were 0.75 (P<.05) for ribeye and 0.82 (P<.05) for back fat thickness. The characteristics of the measures in ultrasound showed good correlations with measures at the moment of slaughter of the ribeye and back fat thickness in differents stages of feedlot. / Doutor

Made available in DSpace on 2014-06-11T19:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-03-16Bitstream added on 2014-06-13T18:45:27Z : No. of bitstreams: 1 andrighetto_c_dr_botfmvz.pdf: 293280 bytes, checksum: dda49cdd60873926170b0a3b5a781ff1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O ultra-som é utilizado também como uma ferramenta para estimar a área de olho de lombo e a espessura de gordura subcutânea em animais de produção. Os trabalhos sobre o uso do ultra-som são direcionados aos bovinos, portanto é imprescindível estudar esta ferramenta na criação dos bubalinos. Foram utilizados 20 bubalinos, da raça Murrah, castrados, descornados, com idade média inicial de 15 meses. Submeteram-se os animais a quatro tratamentos, abatidos aos 75, 100, 125, 150 dias de confinamento. As medidas realizadas foram área de olho de lombo, espessura de gordura subcutânea do dorso (avaliadas entre a 12ª e 13ª costelas) e a espessura de gordura da garupa, mensuradas pelo ultra-som quando os búfalos atingiram o ponto de abate pelo período de confinamento e, na carcaça após o abate, através da. A área de olho de lombo, espessura de gordura do dorso e da garupa, realizadas pelo ultra-som e na carcaça, apresentaram efeito linear crescente (P<0,05). O ultra-som subestimou a área de olho de lombo da carcaça, sendo, a diferença entre as medidas -5,4cm2. A área de olho de lombo para 100kg de carcaça, no último abate foi 27,8cm2 e a espessura de gordura subcutânea do dorso 3,8mm. As correlações medidas pelo ultra-som e na carcaça foram 0,75 (P<0,05) para área de olho de lombo e 0,82 (P<0,05) para espessura de gordura subcutânea no dorso. As características de carcaça medidas por ultra-som, em bubalinos, apresentam boas correlações com as medidas realizadas na carcaça. / The ultrasound is used too as estimate the ribeye and fat thickness. The works about the use of ultrasound are managed to cattle, therefore it is essential to study the use of this tool to raise buffaloes. Twenty castrated, hornless, Murrah buffaloes with average initial age of 15 months old. The buffaloes were separated in four groups that were slaughtered in 75, 100, 125, 150 days of feedlot. The measures were ribeye, back fat thickness (between 12ª and 13ª ribs) and fat thickness in rump, measured by the ultrasound when the buffaloes reached the slaughter point by the feedlot stages and in the carcass at the moment of slaughter. The ribeye, back fat thickness and fat thickness in rump presented linear increase effect (P<.05). The average difference between the ribeye in ultrasound and carcass was 5.4 cm2, we observe that the ultrasound underestimated the ribeye in carcass. The ribeye for 100kg of carcass, the last slaughter was 27.8 cmø and back fat thickness 3.8mm. The increase of fat thickness measure for days in feedlot in carcass and ultrasound was similar between back and rump. The correlations measured by the ultrasound and carcass were 0.75 (P<.05) for ribeye and 0.82 (P<.05) for back fat thickness. The characteristics of the measures in ultrasound showed good correlations with measures at the moment of slaughter of the ribeye and back fat thickness in differents stages of feedlot.

Master of Science / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Large cattle feedlots in Kansas are often considered to be large sources of particulate matter (PM), including PM with equivalent aerodynamic diameter of 10 micrometers or less (PM[subscript]10). To control PM emissions from cattle feedlots, water sprinkler systems can be implemented; however, limited data are available on their PM control efficiency. This research was conducted to determine the control efficiency of a water sprinkler system in reducing PM[subscript]10 emission from a cattle feedlot. This was accomplished by monitoring the PM[subscript]10 concentrations, with tapered element oscillating microbalance (TEOM™) PM[subscript]10 monitors, at the upwind and downwind boundaries of a cattle feedlot (KS1) from January 2006 to July 2009. The feedlot was equipped with a sprinkler system that can apply up to 5 mm of water per day. It had approximately 30,000 head of beef cattle and total pen area of approximately 50 ha. The control efficiency of the sprinkler system was determined by considering the PM[subscript]10 data during sprinkler on/off events, i.e., the sprinkler system was operated (on) for at least one day and either followed or preceded by at least one day of no water sprinkling (off). For each of the selected sprinkler on/off events, the percentage reduction in net PM[subscript]10 concentration was calculated and considered to be a measure of the control efficiency. Net PM[subscript]10 concentration was defined as the difference between downwind and upwind PM[subscript]10 concentrations. The control efficiency for PM[subscript]10 ranged from 32% to 80%, with an overall mean of 53% based on 24-h PM[subscript]10 values for 10 sprinkler on/off events. In general, the effect of the water sprinkler system in reducing net PM[subscript]10 concentration lasted for one day or less. The percentage reduction in net PM[subscript]10 concentration at KS1 due to rainfall events was also determined using a similar approach. In addition, a second cattle feedlot (KS2) that was not equipped with a sprinkler system and with approximately 25,000 head of beef cattle and 68 ha pen area was considered. Percentage reductions in net PM[subscript]10 concentrations due to rainfall events were mostly in the range of 60% to almost 100% for both feedlots, with overall means of 75% for KS1 and 74% for KS2. The effects of rainfall events (with rainfall amounts > 10 mm/day) lasted for three to seven days, depending on rainfall amount and intensity. Limited data are also available on PM[subscript]10 emission rates from cattle feedlots in Kansas. This research quantified PM[subscript]10 emission rates from the two feedlots (KS1 and KS2) and a third cattle feedlot (KS3) in Kansas by using inverse dispersion modeling with the AMS/EPA Regulatory Model (AERMOD), which is the US EPA preferred regulatory atmospheric dispersion model. PM[subscript]10 emission rates were back-calculated using the resulting PM[subscript]10 concentrations modeled by AERMOD, together with measured PM[subscript]10 concentrations (24 months of data for KS1 and KS2, 6 months of data for KS3). Overall mean PM[subscript]10 emission fluxes for the 2-year period were 1.29 g/m[superscript]2-day (range: 0.04 – 4.98 g/m[superscript]2-day) for KS1, 1.03 g/m[superscript]2-day (range: 0.07 – 4.52 g/m[superscript]2-day) for KS2, and 2.48 g/m[superscript]2-day (6-months; range: 0.05 – 5.00 g/m[superscript]2-day) for KS3. The corresponding mean PM[subscript]10 emission factors were 21, 29, and 48 kg/1,000 hd-day for KS1, KS2, and KS3, respectively. The emission factors for KS1 and KS2 were considerably smaller than the published US EPA emission factor for cattle feedlots (i.e., 42 kg/1000 hd-day). The emission factor for KS3 was slightly greater than the US EPA emission factor; however, it was a biased estimate because it was based only on a six-month period.

Call number: LD2668 .T4 1959 W84

Master of Science / Department of Agricultural Economics / Ted C. Schroeder / Very rapid growth in the ethanol industry has led to a void of information regarding price dynamics and utilization of distiller's grains. Understanding market conditions is essential for livestock producers to make informed decisions in the procurement of feedstuffs, especially as grain price levels have recently increased substantially. In this study, distiller's grain price discovery dynamics are evaluated to develop an understanding of spatial price relationships. The knowledge of price relationships reveals that users of distiller's grain should shop around when procuring the feedstuff. Additionally, because animal performance may be altered with increased inclusion of distiller's grains, regional competitive advantages could shift fed cattle production to geographic regions characterized by high of ethanol production plants. Therefore, the cost of current grain processing methods are evaluated to enhance the awareness of regional competitiveness and long term sustainability. The combination of these two objectives allows producers to better realize the implications of the ethanol industry on their ability to maintain their operations into the near future.

Thesis (MScAgric)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: The Dorper is numerically the second most abundent of all the sheep breeds in South Africa. It is the most numerous sheep breed in the dry arid areas of South Africa which make out a very big portion of the natural grazing in South Africa. In this study the feedlot performance was specifically investigated since so little research has been done in this regard. In the first study (Chapter 1), the production efficiency, body components and commercial yield of 13 Dorper and 12 Merino lambs were investigated. A pelleted diet was fed ad lib and the water intake per day was measured. Lambs were slaughtered at 30kg and at 40kg live weight and cut up according to the South African commercial cuts. The weights of the organs, head, feet, skin and carcass were also recorded. Results from the first study showed that Dorpers had a lower (P<0.05) water efficiency (285.97 mVkgO75/day) than the Merinos (240.07 mVkg075/day), but had a higher (P<0.05) nitrogen retention. The head, feet, skin, heart, lungs, kidneys and diaphragm of Merino lambs were heavier (P<0.05). Merinos had heavier (P<0.05) breast and shank and thick rib (only at 40kg live weight) cuts. But the Dorper had a significantly heavier hindquarter (buttock and loin) which is the high-priced cut of any carcass. It seems that the Dorper will do well under feedlot conditions, and would possibly make a better commercial meat producer than the Merino under all circumstances. In the second study (Chapter 2), the free-ranging Dorper on natural grazing were compared with 7 Dorper lambs in the feedlot study. The essential amino acids in the duodenal contents were compared. The free-ranging Dorpers were randomly slaughtered at 40 kg live weight and a duodenal sample was collected. The feedlot Dorpers were also slaughtered at 40 kg live weight and a duodenal sample was taken. The second study indicated no significant differences between the EAA composition of the duodenal samples, whether protein quantity was taken into account (gAA/100g crude protein (CP)) or not (expressed as % of lysine). The chemical scores indicated that the two most limiting amino acids in the duodenal digesta for whole empty body growth were: arginine and histidine. Excess levels of amino acids tend to be present in all three duodenal digesta samples (isoleucine, leucine, lusine, methionine, phenylalaline, threonine and valine). The whole empty body EAA composition (g AA/100 g crude protein) was as follows 7.10 arginine; 2.40 histidine; 3.31 isoleucine; 7.22 leucine; 6.61 lysine; 1.62 methionine; 3.91 phenylalanine; 3.77 threonine and 4.85 valine. The composition can serve as an example of the ideal EAA requirements for whole empty body growth between 30 and 40 kg live weight of Dorper ram lambs. The duodenal amino acid concentrations of the free-ranging Dorper compared well with those of the feedlot Dorpers which suggests that the microbial organisms have a big influence on the amino acid concentration which reaches the intestines. / AFRIKAANSE OPSOMMING: Die voerkraal prestasie en essentiele aminosuur behoeftes van groeiende Dorper lammers: The Dorper is getalgewys die tweede mees talryke skaapras in Suid-Afrika. Dit is die mees talryke skaapras wat in die drce woestynagtige gebiede van Suid-Afrika aangetref word. Die gebiede beslaan die grootste oppervlakte van Suid-Afrika se natuurlike weiveld. In die studie is voerkraal prestasie van die Dorper nagevors, spesifiek omdat daar so min navorsing op hierdie gebied gedoen is. In die eerste studie (Hoofstuk 1) is die produksie doeltreffendheid, liggaams komponente en kornrnersiele produksie van 13 Dorper- en 12 Merino lammers ondersoek. 'n Verpilde rantsoen is ad lib gevoer en die water inname per dag is ook gekontroleer. Die lammers is geslag op 30 en 40 kg lewende gewig en die karkasse is daarna opgesny volgens die Suid-Afrikaanse kornmersiele karkassnitte. Die resultate van die eerste studie het getoon dat Dorpers 'n laer water potentiaal (P<0.05) (285 97 mflkgO 75/dag) as die Merinos (240.07 mVkg075/dag) het. Dorper lammers het ook 'n hoer (P<0.05) stikstof retensie. Die kop, vel, pote, hart, longe, niere en diafragma van Merino lammers was swaarder (P<0.05). Merinos se brisket en dikrib snitte weeg ook swaarder (P<0.05). Die Dorper het 'n beduidende swaarder agterkwart (len de en boud) gehad, wat die duurste snit is van enige karkas. Die Dorper het baie goed gedoen in die voerkraal toestande en sal waarskynlik onder aile omstandighede 'n hcer vleisproduksie op die Merino lewer. In die tweede studie (Hoofstuk 2), is die vryweiende Dopers op natuurlike weiding vergelyk met die Dorpers in 'n voerkraal. Die twee groepe Dorpers se essensiele aminosuur samestelling in hul dunderms is bepaal en vergelyk om te bepaal of daar enige tekorte teenwoordig is. Die Dorpers in die veld en in die voerkraal is op 40 kg lewende gewig geslag en monsters van die dunderm inhoud is gekollekteer. Die monsters is ontleed om te bepaal of daar enige betekenisvolle verskille in die essensiele aminosure van die dunderm inhoud tussen die veld Dorpers en voerkraal Dorpers was. Die tweede studie het geen betekenisvolle verskille getoon tussen die dunderm monsters se essensiele aminosure, of die hoeveelheid proteien (gAA/100g) in aanmerking geneem is of nie (uitgedruk as % lisien). Die chemiese telling dui aan dat die twee mees beperkende aminosure in die dunderm inhoud vir lee liggaam groei arginien en histidien was. Oormaat vlakke van aminosure kom voor in al drie dunderm inhoud monsters (isoleusien, leusien, lisien, metionien, femielalanien, treonien en valien). Die totale lee liggaam essensiele aminosuursamestelling (g aminosuur/100g ruprotein) was soos volg: 7.10 arginien; 2.40 histidien; 3.31 isoleusien; 7.22 leusien; 6.61 lisien; 1.62 metionien; 3.91 fenielalanien; 3.77 treonien en 4.85 valien. Hierdie aminosuursamestelling kan as 'n aanduiding dien vir die ideale aminosuurbehoeftes van Dorper ram lammers vir totale lee liggaamsgroei vanaf 30 tot 40 kg lewende massa. Die dunderm aminosuur konsentrasie van die Dorper in die veld stem goed ooreen met die van die voerkraal Dorper. Dit toon waarskynlik dat die mikrobe organismes in die rumen In groot invloed het op die aminosuur samestelling wat die dunderm bereik.