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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.
1

The effects of nutrient uniformity and modified feed processing on animal performance

Clark, Patrick M. January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Keith C. Behnke / A series of experiments were conducted evaluating the effects of marker selection and mix time on feed uniformity, feed uniformity on animal performance, and the addition of cracked corn to a concentrate pellet on broiler performance. Utilizing a common corn-soybean meal based poultry diet, as mix time increased, there was an overall decrease in % Coefficient of Variation (CV) observed, which was independent of which marker was used. Crude protein should be considered to be an inferior marker as several ingredients in the batch contribute some level of protein and overall decreased numerically less than 1% CV. Synthetic amino acids (methionine and lysine) prevailed as the most consistent markers reducing in magnitude by 60.32% and 55.97% (methionine and lysine, respectively). To evaluate the effects of feed uniformity on broiler performance, as determined by CV, methionine was added to a basal diet and mixed for 10, 20, 30, 40, or 120-s, with methionine being the only ingredient varying. During the starter period (d 0 to 16) ADG increased significantly (quadratic P<0.001) as well as F:G (quadratic P<0.001). However, in overall (d 0 to 41) growth performance only ADG improved (quadratic P<.001). Average daily feed intake appeared to be a contributing factor in growth performance for all stages of growth. Cracked corn was added to a concentrated pellet to evaluate growth performance on broilers and potential cost reductions at the feed manufacturing facility. A linear decrease was observed overall (0 to 41 d) for ADG, ADFI, and F:G (P<0.003, respectively). Gizzard weight and gizzard yield were significantly increased (P<0.043 and P<0.008, respectively) as cracked corn level increased.
2

Application of existing statistical models to thermal inactivation of Escherichia coli in a lab-based circulating water bath and investigation of a Salmonella challenge model in a 42-day broiler grow-out in an updated facility

Carroll, Michael 13 August 2024 (has links) (PDF)
The Food Safety Modernization Act has enforced the importance of research in preventative and control measures for known hazards. Experiment 1 applies existing statistical models, Linear and Weibull, to Escherichia coli thermal inactivation in broiler mash feed in a lab-based circulating water bath to simulate conditioning. Linear and Weibull models were determined to be suitable for modeling the thermal inactivation of E. coli in broiler feed. In Experiment 2, a Salmonella challenge model for broilers raised in floor pens in the updated Animal Biosafety Level-2 facility was evaluated over a 42-day grow-out period. Broiler performance and recovery of Salmonella from liver, spleen, ceca, and external bird rinses were measured for Salmonella challenged and unchallenged groups of Ross 708 male broilers in five different rooms. The five different rooms utilized in the study performed similarly to each other and can be used as replicate blocks in future experiments.
3

Evaluating flushing procedures to prevent drug carryover during medicated feed manufacturing

Martinez-Kawas, Adrian January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Leland McKinney / Carryover of medicated feed additives between batches of feed can potentially result in harmful drug residues in the edible tissues of food-animals. Flushing the equipment with an ingredient, such as ground grain, is one method used to remove any residual medicated feed from the system. It is generally recommended that the quantity of flush used be between 5 and 10% of the mixer's capacity. However, there is little data that supports this recommendation. Therefore, two experiments were conducted to 1.)determine which manufacturing equipment is the major source of carryover, 2.)evaluate which flush size adequately prevents drug carryover, and 3.) quantify the interrelationship between flush size and drug concentration. In Experiment 1, feed medicated with nicarbazin (Nicarb 25%®; 0.0125%) was manufactured and conveyed from the mixer, through a drag conveyor and bucket elevator, and then into a finished product bin. The system was then flushed using ground corn in the amount of 2.5, 5, 10, 15, or 20% of the mixer's capacity (454.5 kg). Subsequently, a non-medicated diet was conveyed through the system and samples were collected and analyzed for nicarbazin. No significant (P > 0.05) differences were detected among the flush treatments, and all treatments were effective in preventing nicarbazin carryover to the non-medicated diet. In Experiment 2, feed medicated with three levels of monensin (Rumensin® 80; 100, 600, and 1,200 g/ton) was manufactured and handled in the same manner as in Experiment 1. The flushing treatments examined were: 1, 2.5, and 5% of the mixer's capacity. Samples of the non-medicated diet for each treatment were collected and analyzed for monensin. There was significant interaction (P < 0.05)between drug level and sampling location between treatments. As the drug level in the medicated diet increased, higher concentrations of monensin were detected in the non-medicated diet. Collectively, these studies demonstrate that a 2.5%, even a 1% flush size, is effective in preventing carryover of medicated feed additives. It was also demonstrated that the bucket elevator and finished product bin were the major sources of drug carryover in this particular feed manufacturing system.
4

Effects of feed manufacturing on nutrient metabolism, nutrient retention, and growth performance of broiler chickens

Rude, Christopher Mark January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / R. Scott Beyer / Broiler chicken feed is processed. Cereal grains are ground to reduce particle size and the feed usually is pelleted. When pelleted, broiler diets are steam conditioned and forced through a die causing varying levels of starch gelatinization. Cereal grain particle size and starch gelatinization can be controlled during feed manufacturing. Earlier research has shown that starch gelatinization negatively affects growth performance of 0 to 21 d of age. An experiment was conducted to determine the effects of corn particle size and starch gelatinization on growth performance, dressing percentage, and gizzard size when fed to 22 to 42 d of age broilers. Increasing particle size from 470 to 1240 μm increased body weight gain, dressing percentage, and relative gizzard size. Starch gelatinization increased relative gizzard size. No interaction effects were detected. To expand on previous experiments, a trial was conducted to investigate the effect of starch gelatinization on broiler chick gastrointestinal pH, glucose absorption, and glucoregulation. Starch gelatinization level affected jejunum pH, with a higher pH reported at 20% starch gelatinization. Increases in starch gelatinization decreased blood glucose and increased glucagon level. Highest measured glucagon level was reported in broiler chicks fed the diet with 20% starch gelatinization level diet after 6 hours of starvation. A third experiment was conducted to determine the effect of starch gelatinization on metabolizable energy and amino acid digestibility. Increasing starch gelatinization from 0 to 100% increased true metabolizable energy and fecal output in roosters. No effect was found on apparent metabolizable energy or amino acid digestibility, with an increase in starch gelatinization from 0 to 20%. Increasing particle size from 470 to 1240 μm had a positive effect on 22 to 42 d growth performance. A starch gelatinization level of 20% or lower had no effect on metabolizable energy or amino acid digestion. Older broilers with larger gastrointestinal tracts are unaffected by 20% gelatinized starch; whereas, 20% gelatinized starch reduced blood glucose and increased glucagon levels of young broilers. Lower blood glucose and increased glucagon are indicative of lower glucose storage, and could cause reduced young broiler growth performance when fed diets with gelatinized starch.
5

Evaluation of surface sanitation to prevent biological hazards in animal food manufacturing

Muckey, Mary Beth January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Cassandra K. Jones / Animal food manufacturing facilities need to evaluate biological hazards within their facility due to their severity and probability to cause illness or injury in humans or animals. Control of biological hazards, including Salmonella and Porcine Epidemic Diarrhea Virus (PEDV), in animal food manufacturing facilities may require a preventative control to mitigate the risk of the hazard. Thermal processing is an effective point-in-time control, but does not prevent cross-contamination during drying, cooling, and packaging/load-out of animal food. Therefore, it may be appropriate to sanitize surfaces to prevent cross-contamination of animal food during manufacturing. The objective of the first experiment was to evaluate surface decontamination strategies for Porcine Epidemic Diarrhea Virus (PEDV) using chemical disinfectants to reduce viral RNA on various manufacturing surfaces. Concentrated liquid formaldehyde and sodium hypochlorite reduced the quantity of viral PEDV RNA on all tested surfaces. Rubber belting from a bucket elevator retained the most PEDV RNA, while the polyethylene tote bag retained the least. In the second experiment, surface decontamination was evaluated for Salmonella Typhimurium using liquid and dry chemical sanitizers on various manufacturing surfaces. Surfaces treated with concentrated commercial formaldehyde had no detectable Salmonella after treatment, and surfaces treated with medium chain fatty acids (MCFA) had at least a 4-log reduction compared to the control. The dry commercial acidulant, sodium bisulfate, was the most effective dry sanitizer tested, but had limited efficacy depending on surface type. Experiment 3 further tested the application of two chemical sanitizers against Salmonella Enteritidis on residual surface and feed contamination in pilot-scale mixers. Manufacturing sequence, but not treatment impacted feed and surface contamination of Salmonella Enteritidis. Specifically, there was Salmonella-positive residue in the batch of feed manufactured immediately after the positive control batch. However, no Salmonella residue was detected in batches of feed treated with either concentrated commercial essential oil blend or rice hulls treated with 10% MCFA. Low levels of Salmonella residues were observed from feed and surfaces manufactured after Sequence 1, but no residues were observed by Sequence 2. This data suggests that sequencing of feed during manufacturing can reduce Salmonella-positive contamination within animal food and on manufacturing surfaces, particularly after the second batch or with the use of chemical treatments. In summary, liquid sanitizers have been shown to be effective at reducing Salmonella spp. and PEDV contamination on a variety of animal food manufacturing surfaces, but application and practicality may be limited.
6

Evaluation of an alternative organic waste disposal system in Chevron-Escravos : a case study / O.I. Bojor

Bojor, Olire Innocent January 2008 (has links)
Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
7

Evaluation of an alternative organic waste disposal system in Chevron-Escravos : a case study / O.I. Bojor

Bojor, Olire Innocent January 2008 (has links)
The research presented in this dissertation focuses on the waste management techniques currently used by Chevron-Escravos Nigeria Limited (CENL), as background knowledge of the existing waste disposal system practiced by the company. Investigation has shown that more than four tons (4tons) of organic food waste that CENL generates daily is being disposed of by using incineration and landfilling of the resulting residues. The high recoverability and economic values in form of nutrients and stored energy is not being considered. The main dissertation problem was to develop an alternative means of promoting the economic and environmental recoverability of these huge amounts of organic wastes, by developing a disposal technique other than the current incineration and landfill methods. The mechanism considered to achieve this objective was laid out in the customized organic waste converter or processor that provides one of the baselines for this dissertation. It also presents a procedural description of converting organic food waste to bio-feeds and feedstock of high quality. This alternative processing and utilization of organic food waste was carried out to provide information about tradeoffs to the current practice of incineration and landfill management systems. This was done to guide decision making and to serve as a framework within which the plausibility of the proposed solution could be examined. A comparative analysis of the two scenarios of waste to feed and waste to incineration system, the environmental impact, economic viability, and opportunity cost of recycling organic food waste produce of animal bio-feed was assessed by using: • Life cycle analysis (LCA) • By-products Breakeven Sale Product (BBSP) model. The BBSP model evaluates the opportunity of recycling the organic food waste in production of animal bio-feed to waste incineration. The outcome of the dissertation indicates that incineration is an important contributor to human and environmental toxicity and global warming. The proposed solution (recycling approach) balances the socio-economic, political and environmental safety by producing renewable, clean and eco-friendly feed and by-products. It was also concluded that there are alternative possibilities for the utilization of industrial organic food waste, where both the energy and nutrients are completely utilized, rather than the norms of conversion through chemical, biological, and thermal or other forms of energy fuels), which typically utilizes only one of these (calorific contents) categories at a time. The above mentioned utilization can be achieved by transforming the current waste disposal system. By introducing an alternative model for the recycling of plant and animal nutrients and the utilization of energy, renewable energy can be saved, human health and the environment can be protect and a sustainable economy can be maintained. In summary, it was demonstrated that there is huge capital losses and environmental contamination due to the current waste management practices. Recycling of OF W for feed production would be cost effective method that contributes towards protecting the environment achieving economic sustainability. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
8

Evaluation of an alternative organic waste disposal system in Chevron-Escravos : a case study / O.I. Bojor

Bojor, Olire Innocent January 2008 (has links)
The research presented in this dissertation focuses on the waste management techniques currently used by Chevron-Escravos Nigeria Limited (CENL), as background knowledge of the existing waste disposal system practiced by the company. Investigation has shown that more than four tons (4tons) of organic food waste that CENL generates daily is being disposed of by using incineration and landfilling of the resulting residues. The high recoverability and economic values in form of nutrients and stored energy is not being considered. The main dissertation problem was to develop an alternative means of promoting the economic and environmental recoverability of these huge amounts of organic wastes, by developing a disposal technique other than the current incineration and landfill methods. The mechanism considered to achieve this objective was laid out in the customized organic waste converter or processor that provides one of the baselines for this dissertation. It also presents a procedural description of converting organic food waste to bio-feeds and feedstock of high quality. This alternative processing and utilization of organic food waste was carried out to provide information about tradeoffs to the current practice of incineration and landfill management systems. This was done to guide decision making and to serve as a framework within which the plausibility of the proposed solution could be examined. A comparative analysis of the two scenarios of waste to feed and waste to incineration system, the environmental impact, economic viability, and opportunity cost of recycling organic food waste produce of animal bio-feed was assessed by using: • Life cycle analysis (LCA) • By-products Breakeven Sale Product (BBSP) model. The BBSP model evaluates the opportunity of recycling the organic food waste in production of animal bio-feed to waste incineration. The outcome of the dissertation indicates that incineration is an important contributor to human and environmental toxicity and global warming. The proposed solution (recycling approach) balances the socio-economic, political and environmental safety by producing renewable, clean and eco-friendly feed and by-products. It was also concluded that there are alternative possibilities for the utilization of industrial organic food waste, where both the energy and nutrients are completely utilized, rather than the norms of conversion through chemical, biological, and thermal or other forms of energy fuels), which typically utilizes only one of these (calorific contents) categories at a time. The above mentioned utilization can be achieved by transforming the current waste disposal system. By introducing an alternative model for the recycling of plant and animal nutrients and the utilization of energy, renewable energy can be saved, human health and the environment can be protect and a sustainable economy can be maintained. In summary, it was demonstrated that there is huge capital losses and environmental contamination due to the current waste management practices. Recycling of OF W for feed production would be cost effective method that contributes towards protecting the environment achieving economic sustainability. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.

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