Rozprawy doktorskie na temat „Animal waste”

Organic phosphorus (P$ sb{ rm o}$) in farm animal wastes must be mineralized to inorganic P for subsequent plant use. This study was conducted to determine if feed additives affect P$ sb{ rm o}$ mineralization, manure decomposition, and plant growth. Feed additives in aqueous systems affected the P mineralization of inositol hexaphosphate by phytase and of adenosine monophosphate by alkaline phosphatase. Pronounced effects were produced by bacitracin and both enzymes and by neomycin on phytase. Feed additives in dairy cattle (Bos taurus L.) manure produced effects on microbial activity as measured by gas production that differed from those produced on fecal phosphatase activity. Additives applied directly or with manure to Ste. Rosalie clay, Greensboro loam, or silica sand had no effect on barley (Hordeum vulgare L.) yield but did produce additive, rate, growth medium, and manure dependent effects on plant P concentration and soil phosphatase activity. Therefore, each feed additive must be independently evaluated to determine its effect on biological systems.

Co-combustion of animal carcasses and slaughterhouse waste products (animal waste), which are classed as high-risk infectious waste, has been considered as a “fuel opportunity” for waste-to-energy boilers. In this study, the impact of co-combustion of animal waste with municipal solid waste (MSW) on operational issues such as bed agglomeration, deposit formation and emission was investigated, employing experimental and theoretical methods. In the experimental section, a series of full-scale tests in a bubbling fluidised-bed boiler were carried out, to determine the effects of animal waste co-combustion on the issues addressed. Two combustion scenarios were considered, identified as the reference (Ref) case and the animal waste (AW) case. In the Ref case, a solid-waste fuel mix, consisting of sorted and pretreated industry and household waste was combusted. In the AW case, 20 wt% AW was added to the reference fuel mix. The collected samples, which included super-heater deposits, fuel mixes and bed and fly ashes, were analysed, using chemical fractionation, SEM-EDX and XRD. In addition, the flue gases´ emission rate were continuously analysed, using FTIR spectrometry. The results showed positive effects from co-combustion of AW, indicating decreased deposit formation and lower risk of bed agglomeration, as well as reduced emissions of NOx and SO2. Moreover, it was found that the concentrations of P, Ca, S and Cl were enriched in the bed materials. In the theoretical section, thermodynamic calculations, with respect to experimental data, were performed to provide greater understanding of the ash transformation behaviour and the related melting temperature. The calculations mainly focused on bed agglomeration, where addition of AW to the MSW considerably reduced the risk of agglomeration. The results of equilibrium products and phase diagram information for the bed ashes suggested melt-induced agglomeration as a possible cause of the formation of sticky layers on the bed particle in the Ref case. Moreover, it was concluded that higher amounts of calcium phosphate and sulfates increased the first melting temperature of the bed ashes in the AW case.

Sponsorship:

Waste Refinery and Sparbanksstiftelsen Sjuhärad

Six odor-reducing commercial products were tested for their efficacy in reducing odors from dairy and swine wastes. A sensory panel method was utilized for odor evaluations, in which the panel played an important part. Comparisons between products were made for agitated and unagitated conditions and effect of storage time (three weeks in which experiments were performed). Cotton pieces tied to the mouth of the sample jars were useful in absorbing the odors. Odor-treated jars were observed and evaluated by panel members. The odors were rated on a discrete scale of 0-5, with '0' being no odor and '5' the highest odor level of dairy or swine waste. The products were analyzed for their effectiveness on dairy and swine wastes separately. The "General Linear Model" was used for data analyses, and all the products were compared for their effectiveness under each waste storage condition and elapsed storage time. Each product was able to reduce odors. For both dairy and swine wastes, one product stood out and was very effective, whereas another product was less successful. Unagitated storage conditions of swine waste favored the product performance. Unagitated storage conditions were also found to be better for most of the products; only two products were slightly better in effectiveness under agitated storage conditions. The effect of storage time on product-effectiveness for each product for both dairy and swine waste varied. Odor levels from unagitated swine waste was very low in the beginning, but became worse with increasing storage time. Dairy waste in unagitated conditions had slightly higher levels of odors in the beginning, but became a little less with increasing storage time. Under the conditions of this study, it can be recommended that: 1) P2 has a better chance in reducing odors, 2) in general, unagitated conditions favor the reduction in odor levels, and 3) dairy waste should be treated in the first few days following collection, whereas swine waste should be treated when it is old. Testing of these products in actual field conditions would provide stronger support for these findings.
Master of Science

In 1998, two upper North Bosque River segments were designated as impaired due to the nonpoint source (NPS) pollution of phosphorus (P) to these segments in the watershed. As a result, two Total Maximum Daily Loads (TMDLs) were applied which called for the reduction of annual loading and annual average soluble reactive P (Sol P) concentrations by 50 %. This study was conducted to evaluate the efficacy of two prospective new technologies, an Electrocoagulation (EC) system, and a Geotube® dewatering system to potentially aid the dairy farmers in meeting the goals set by the TMDLs. The EC system analyzed in this study used chemical pretreatment to coagulate and separate solids in effluent pumped from the dairy lagoon; the liquid then flowed over charged iron electrodes giving off ions that cause coagulation and precipitation of P and other metals. Overall, the performance of the system was consistently highly effective in reducing total phosphorus (TP) and Sol P, on average, reducing these constituents by 96% and 99.6% respectively from the dairy lagoon effluent. However this consistency did not hold for the rest of the analytes. In the Geotube® dewatering system geotextile tubes were utilized to dewater dairy lagoon effluent. Results showed this system performed very well in filtering solids from the dairy lagoon effluent, removing an average of 93.5 % of the total solids between the two pumping and dewatering events of March and April. It was effective in removing nutrients and metals as well. The average percent reduction of TP and Sol P for the two events were very high at 97% and 85 % respectively.

Use of an induced blanket reactor (IBR) to break down organic matter into methane is a financially attractive method to reduce the environmental impact of animal or industrial waste. In order to better understand the biological processes involved with the conversion of waste to biogas by an IBR, it is necessary to gain a better understanding of the microorganisms and their roles in the reactor. Molecular techniques based on the isolation of 16S rDNA were used in order to avoid the limitations posed by conventional culture-based techniques. Total DNA was extracted and amplified using universal primers specific to eubacteria and archaea with the purpose of identifying the dominant microorganisms in the IBR. The amplified DNA was separated based on its sequence composition by denaturing gradient gel electrophoresis (DGGE). Several bands were then excised, cloned, and sequenced, in order to characterize the phylogenetic affiliation of many of the microorganisms and create a useful molecular fingerprint. By using this approach, close relatives of several microorganisms that are typical in anaerobic digestion have been identified, including species of Clostridium, Flavobacterium, Bacteroides, Spirochaeta, Methanobrevibacter, and Methanosarcina. Several species were also identified whose role in the reactor is not completely understood, consisting of relatives of Dehalococcoides, Planctomyces, Aequorivita, and Sedimentibacter species. The information obtained in this project may enable refinements that promote desirable reactions and enhance reactor efficiency.

Microalgae have a variety of commercial applications, the oldest of which include utilisation as a food source and for use in wastewater treatment. These applications, however, are seldom combined due to toxicity concerns, for ethical reasons, and generally the requirement for cultivation of a single algae species for use as a feed supplement. These problems might be negated if a “safer” wastewater such as that from agricultural and/or commercial food production facilities were to be utilised and if a stable algae population can be maintained. In this investigation preliminary studies were carried out using an Integrated Algae Pond System (IAPS) for domestic wastewater treatment to determine the species composition in the associated High Rate Algae Ponds (HRAPs). The effect of different modes of operation, continuous versus batch, on nutrient removal, productivity and species composition was also investigated. Furthermore, indigenous species in the HRAP were isolated and molecularly identified as, Chlorella, Micractinium, Scenedesmus and Pediastrum. Additionally, the effect of the nor amino acid, 2-hydroxy-4-(methylthio)-butanoic acid (HMTBA) and its Cu-chelated derivative, on the growth and biochemical composition of Chlorella, Micractinium, Scenedesmus, Pediastrum and Spirulina was investigated. Species composition in the HRAP was stable under continuous operation with Micractinium dominating > 90% of the algae population. Under batch operation the population dynamic shifted; Chlorella outcompeted Micractinium possibly due to nutrient depletion and selective grazing pressures caused by proliferation of Daphnia. Higher species diversity was observed during batch mode as slower growing algae were able to establish in the HRAP. Nutrient removal efficiency and biomass productivity was higher in continuous mode, however lower nutrient levels were obtained in batch operation. HMTBA did not significantly affect growth rate, however treatment with 10 mg.L-1 resulted in slightly increased growth rate in Micractinium and increased final biomass concentrations in Chlorella, Micractinium and Spirulina (although this was not statistically significant for Micractinium and Spirulina), which are known mixotrophic species. Algae treated with Cu-HMTBA, showed reduced final biomass concentration with 10 mg.L-1, caused by Cu toxicity. Biochemical composition of the algae was species-specific and differed through the growth cycle, with high protein observed during early growth and high carbohydrate during late growth/early stationary phase. Additionally, 0.1 mg.L-1 HMTBA and Cu-HMTBA significantly reduced protein content in Chlorella, Micractinium, Scenedesmus and Pediastrum. In conclusion, operation of the HRAP in continuous culture provided suitable wastewater treatment with high productivity of an ideal species, Micractinium, for use in animal feed supplementation. This species had 40% protein content during growth (higher than the other species tested) and dominated the HRAP at > 90% of the algae population during continuous mode. Addition of HMTBA (> 1 mg.L-1) to algae cultivation systems and those treating wastewater, has the potential to improve productivity and the value of the biomass by enhancing protein content. Overall, the co-utilisation of microalgae for wastewater treatment and the generation of a biomass rich in protein, for incorporation into formulated animal feed supplements, represents a closed ecosystem which conserves nutrients and regenerates a most valuable resource, water.

Animals with multi-compartmented stomachs, also known as ruminants, are adapted to digest cellulosic materials, which constitute the primary expense on ranches and dairies. Industrial byproducts can be repurposed for livestock diets to decrease these costs. Therefore, finding alternative feedstuffs may benefit the economics of livestock production. The goal of this project was to evaluate alternative uses of ruminal waste from commercial abattoirs. This project addressed two primary objectives. First, ruminal fiber as a potential dietary fiber source was evaluated. Second, the potential for preservation of ruminal fluid for later use was assessed. Results for the first objective indicated harvesting rumen waste from slaughterhouses could be beneficial for sustainable livestock production, while reducing the environmental threat posed by disposal of ruminal waste. Nutritional values of rumen waste in relation to other common livestock roughages sources commonly found in ruminant diets are numberical , such as coastal Bermuda grass hay (Cynodon dactylon ) and alfalfa hay (Medicago sativa). Neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL) and crude protein (CP) values were 68.1%, 39.9%, 10.9% and 15%, respectively. Contribution to variance for NDF, ADF, ADL and CP were 97.2%, 97.9%, 95.4% and 19.1%, respectively. In vitro true digestibility (IVTD) and in vitro neutral detergent fiber digestibility (IVNDFD) were 46.2% and 21.6%, respectively. Results from the second objective showed lower degradation of feeds when frozen or lyophilized rumen fluid was used rather than fresh inoculum; however, differences in IVTD and IVNDFD suggest that, in the absence of fresh inocula, preserved rumen fluid may be a viable option. Implications from this study show rumen content could provide nutrients if fed to livestock and rumen microbes preserved (frozen or lyophilized) are still viable and able to degrade feedstuffs. Therefore, further research is needed to assess the consistency of using inoculum from slaughtered cattle and improve the preservation process.

Biodiesel (BD) is conventionally produced by the transesterification of vegetable oils or animal fats with a monohydric alcohol and base catalyst, and known for its many technical and environmental advantages over petrodiesel. However, these oils are not economically viable feedstock due to their value as edible oils. Alternative, inexpensive feedstocks with minimal to no food value such as the large quantities of fishery and animal processing by-products which are often discarded as waste were explored in this project. Lipase was investigated as an alternative to chemical catalyst due to the tolerance of the former to a wide variety of feedstocks and simpler post-production processes among other advantages. Approximately 23.32-61.53% (on dry weight basis) of salmon skin oil (SSO) was recovered by the various solvent extraction systems evaluated. The quality of SSO stored at 25, 4, -18, and -80oC were assessed over time (1- 45 days) with respect to changes in the fatty acid profile, free fatty acid (FFA) content, peroxide value, and thiobarbituric acid reactive substances. A Fourier transform infrared (FTIR) spectroscopic method was assessed as an alternative to the conventional AOCS titrimetric method for the determination of FFA content. With modifications, the new method was found to be capable of responding linearly to oleic acid (0-6.5%) addition, producing a FFA calibration equation with a S.D. of ±0.014% FFA. Based on the results from the initial assessment of the effects of temperature (25-65oC), oil:alcohol molar ratio (1:1-1:6), alcohol type (ethanol/methanol), and time (8-120 h) on Lipozyme®-IM-catalyzed transesterification of the recovered SSO, a commercial blend of yellow grease and rendered animal fat, and olive oil to fatty acid ethyl ester (FAEE) for use as BD, the process was considered for optimization. In three experiments, the linear, quadratic, and bilinear effects of the reaction variables on FAEE yield were assessed with response surface methodology (RSM) based on central composite rotatable design (CCRD). In each experiment, second-order polynomial models fitted to FAEE yield provided response surfaces at the various reaction times (8-48 h). These models were generally significant and produced reliable and stable predictions. The optimum conditions were found to be close to the centre point of the reaction variables. A high performance liquid chromatography unit equipped with a size exclusion column, and a refractive index detector was used for the simultaneous separation, identification, and quantitation of the reaction components; FAEE, unreacted triacylglycerol, residual diacyl- and monoacylglycerol, and alcohol as well as FFA. The transesterified oils were also tested for various fuel properties. To expand the uses of lipase recovered from fish processing discards to include catalyst for BD production, lipase from crude preparations of delipidated grey mullet (Mugil cephalus) viscera were isolated on para-aminobenzamidine agarose and immobilized on octyl Sepharose CL-4B (o-Sep). A signal in the amide I absorption region of the FTIR spectrum was attributed to the protein layer on o-Sep. Immobilized grey mullet lipase (GMLi) had a 10°C higher optimum temperature compared to the free enzyme (GML) for the hydrolysis of para-nitrophenyl palmitate. Immobilization lowered the enthalpy of activation (ΔH*), and free energy of activation (ΔG*) by more than 313 and 1315 cal/mol, respectively, while it enhanced the reusability, thermal, storage, and organic solvent stabilities of GML.
Le biodiesel (BD), ou des esters d'alkyle, est classiquement produit par la transestérification d'huiles végétales ou de graisses animales avec un monoalcool et un catalyseur de base, et est également connu pour ses nombreux avantages techniques et environnementaux par rapport au pétrodiesel. Toutefois, ces huiles BD ne sont pas des matières premières économiquement viables en raison de leur valeur principale en tant qu'huiles comestibles. Ce projet a exploré des matières premières de substitution, peu coûteuses avec peu ou pas de valeur alimentaire telle que les grandes quantités de sous-produits detransformation du poisson et de sous-produits animaux qui sont souvent jetés avec les déchets. La lipase a été étudiée comme une alternative aux catalyseurs chimiques en raison de la tolérance de la lipase à une grande variété de matières premières ainsi que son processus de post-production beaucoup plus simple entre autres avantages. Environ 23,32 et 61,53% (sur la base du poids sec) de l'huile de peau de saumon (SSO) a été récupéré selon les différents systèmes de solvants évalués. Pour la détermination de la teneur en FFA, une méthode de spectroscopie infrarouge à transformée de Fourier (FTIR) a été évaluée comme une alternative au procédé AOCS conventionnel. Avec des modifications, la nouvelle méthode a été jugée capable de répondre de façon linéaire à l'addition d'acide oléique (0 à 6,5%), avec la production d'une équation d'étalonnage FFA avec une SD de ±0,014% FFA. Sur la base des résultats de l'évaluation initiale des effets de la température de réaction (25-65°C), un rapport l'huile:alcool molaire (1:1-1:6), le type d'alcool (éthanol ou méthanol), et le temps de réaction (8-120 h) sur du la transestérification catalysée Lipozyme®-IM, un mélange commercial de graisse animale jaune et de graisses fondues (RC), et d'huile d'olive (OO) à ester éthylique d'acide gras (EEAG) pour une utilisation comme BD, le procédé a été considéré pour optimisation. Dans trois expériences, les effets linéaires, quadratiques et bilinéaires des variables de la réaction sur le rendement EEAG ont été évalués avec la méthode de réponse de surface (RSM) basée sur la conception centrale composite rotative (CCRD). Dans chaque expérience, des modèles polynomiaux du second ordre équipés d'EEAG ont modelé le rendement des surfaces de réponse fournis aux divers temps de réaction (8-48 h). Ces modèles sont généralement importants et produisent des prévisions fiables et stables. Les conditions optimales ont été trouvées être proche du point de centre des variables de réaction (50°C, charge de l'enzyme 39.06 U, et l'huile:rapport molaire de l'alcool 1:2), et simultanément identifiés, et quantifiés. Les différents composants de la réaction (par exemple: EEAG, triacylglycérol n'ayant pas réagi (TAG), diacyle et résiduelle monoacyle-glycérol (DAG et MAG), et l'alcool ainsi que la FFA), ont été séparés, identifiés et quantifiés en utilisant la chromatographie liquide à haute performance équipé d'unité de colonne d'exclusion de taille, et un détecteur par indice de réfraction. Pour élargir les usages de la lipase récupérée à partir de rejets de transformation du poisson pour inclure un catalyseur pour la production de BD, de la lipase à partir de préparations brutes de délipidé mulet (Mugil cephalus) les viscères ont été isolées sur le para-aminobenzamidine agarose (p-ABA) et immobilisées sur Sepharose CL-octyle 4B (o-Sep). Un signal dans la région d'absorption amide I du spectre FTIR a été attribué à la couche de protéine sur o-Sep. La lipase de mulet immobilisée (GMLi) a eu une température optimale de 10°C plus élevée par rapport à l'enzyme libre (GML) pour l'hydrolyse de para-nitrophényl palmitate (p-NPP). L'immobilisation a abaissé l'enthalpie d'activation (AH*), et l'énergie libre d'activation (AG*) de plus de 313 et 1315 cal/mol, respectivement, alors qu'alla améliorer la capacité thermique, la, réutilisabilité, et la stabilité des solvants des GML.

Antibiotics are added to animal feeds as prophylactic agents and to encourage weight gain in livestock. However, there is concern that the widespread use of antibiotics in animal agriculture encourages for the selection of resistance genes and has contributed to the rise of multiply antibiotic resistant strains of pathogenic bacteria. For this reason, there is interest in quantifying antibiotics in environmental samples. The determination of three antibiotics in swine waste, namely chlortetracycline, tetracycline and oxytetracycline, using LC-MS with electrospray ionization is presented here in. Antibiotics from swine waste were quantified across the lifespan of the swine. Trends were present in each of the four life stages (gestation, farrowing, nursery, and finishing). The nursery stage of life presented the most dominate concentrations and the most consistent trend in antibiotic concentrations.

The global increase in livestock and poultry production observed in the last decades has led to an increase in animal waste generated. The animal waste contains high levels of nitrogen and may carry antibiotics that can disturb important microbial activities such as denitrification in terrestrial and aquatic ecosystems. Disturbances of microbial denitrification can have detrimental consequences to environmental health. In the terrestrial environment, denitrification is an important source and sink of N2O, a potent greenhouse gas in the atmosphere. In aquatic ecosystems, denitrification is a dominant NO3- removal pathway, contributing to prevent eutrophication. The overall goal of this dissertation is to evaluate the impacts of animal waste and potential antibiotic exposure on microbial communities responsible for denitrification in terrestrial and aquatic ecosystems. To achieve this goal, a combined approach of measuring activity rates and performing a molecular characterization of the microbial communities was used. In Chapter 2, the microbial community changes associated with the impacts of acute antibiotic exposure on denitrification were evaluated in soil microcosms. Antibiotic exposure caused a significant increase in N2O production from denitrification. This increase was paralleled with a greater ratio of fungi:bacteria abundance and lower abundances of particular taxa with N2O reduction capacity. In Chapter 3, the impacts of animal manure and antibiotic contamination on N2O fluxes and the abundance of denitrification genes were investigated in soil mesocosms. N2O fluxes in soils treated with manure fertilizer and tetracycline were considerably higher than in control soils. The manure fertilization and antibiotic exposure had diverse effects on different bacterial taxa responsible for N2O production. In Chapter 4, the denitrification activity and microbial community structure in tidal creek sediments impacted by wastewater discharge from a poultry processing plant were evaluated through a field survey and a microcosm experiment. Denitrification rates were inhibited in the location affected by the wastewater discharge. This decrease in denitrification activity was associated with changes in the microbial community structure, such as a lower relative abundance of bacterial taxa carrying denitrification genes and lower abundance of N2O reducing bacteria. In Chapter 5, the abundance and diversity of antibiotic resistance genes were evaluated in a tidal creek impacted by wastewater discharge from a poultry processing plant. The numbers of antibiotic resistance genes were higher in the location closer to the wastewater discharge, suggesting an historic antibiotic exposure associated with the activity of the poultry processing plant. Overall, this work provides new knowledge of the impacts of animal waste and antibiotics on N2O emissions in terrestrial ecosystems and microbial NO3- removal in aquatic ecosystems. This dissertation emphasizes the functional importance of microbial communities to ecosystem health and their responses to anthropogenic disturbance.

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The greatest management concern with animal wastes is the movement of nitrate into water supplies. Health problems in humans and livestock can result from excessive levels of nitrate in drinking water. This publication outlines the guidelines to minimizing the risk of contaminating your drinking water. It also lists a number of questions to check if your management practices in the collection and storage of animal wastes may pose a risk to your groundwater.

The most cost effective treatment scheme for effluent from Midfield Meats, an abattoir in Warrnambool, Australia, was evaluated via a series of laboratory and commercial scale experiments. Effectiveness was measured in terms of suspended solids (SS) and biological oxygen demand (BOD) reduction. Economic assessment was based on predicted reduction in trade waste charges versus infrastructure and running costs. From the range of potential treatment technologies, those deemed most appropriate for trialling included pre-screening, sedimentation, coagulation and flocculation treatment and dissolved air floatation (DAF). Prior to evaluation of treatment types, flow, loads and contaminant characterisation of the waste streams was conducted to aid in selection of treatment type and capacity. Prescreening was found to be the most cost effective, followed by sedimentation, coagulation and flocculation treatment and finally DAF. The most economical treatment scheme that satisfied the requirements of Midfield Meats included a combination of prescreening and sedimentation. DAF and coagulation and flocculation treatment satisfactorily treated the wastewater, however were not cost effective under the current trade waste agreement.

An extensive 10 year monitoring project was initiated in 1986 to examine the effects of a combination of BMPs on surface water quality within a watershed with complex land use. This research specifically examined bacteriological water quality and BMP impacts. Bimonthly grab samples were collected from four surface water monitoring stations, including the watershed outlet, and analyzed for fecal coliform, total coliform, and fecal streptococcus bacteria. Other data compiled from the watershed included hydrologic, meteorologic, geologic and land use data, also collected on a regular basis. Data were collected continuously throughout the project, and thus included both pre- and post-BMP monitoring data. BMP implementation included animal waste storage facilities, nutrient management plans, conservation tillage, alternative water sources for livestock, fences, vegetative filter strips, runoff diversions, and others.

Statistical analysis of the monthly precipitation data indicated no significant difference in rainfall quantity between the pre-BMP and post-BMP monitoring periods. Monthly runoff totals increased 39% from the pre- to the post-BMP periods at the watershed outlet. Increases at all of the subwatershed outlets occurred as well (B, 40%; C, 38%; D, 16%). Statistical analysis did not show a significant difference in runoff between the two monitoring periods, except at station C, where post-BMP runoff was significantly greater than the values measured during the pre-BMP period.

Overall reductions in the mean (geometric) levels of total coliform, fecal coliform and fecal streptococcus bacteria observed at the watershed outlet were 81%, 30% and 76%, respectively. Both parametric and nonparametric statistical analysis techniques were applied to the bacteriological data. Regression analysis of the fecal coliform data showed an increase during the pre-BMP period followed by a decrease post-BMP and a statistically significant difference between the two periods (p=0.004). No trends were evident. Only one of the four stations had a statistical difference between pre- and post-BMP fecal streptococcus data, however, a downward trend was present at every station. No statistically significant difference between the pre- and post-BMP total coliform bacteria was evident, although a downward trend was present at the watershed outlet. These findings indicate that the combination of BMPs implemented in the watershed were effective in reducing the loss of fecal bacteria to receiving streams via overland flow.
Master of Science

Orientador: Jorge de Lucas Junior
Banca: Sergio Campos
Banca: Mônica Sarolli S. de Mendonça Costa
Resumo: O Brasil apresenta grandes potencialidades na produção de alimentos, porém as formas empregadas para atendimento desta demanda têm levado ao aumento da geração de resíduos, fato que justifica o estudo de práticas de reciclagem, tais como a compostagem e a biodigestão anaeróbia desses materiais, pois, além da agregação de valor devido à transformação de resíduos potencialmente poluidores em adubo orgânico e geração de energia (biogás) ainda contribui para um saneamento eficaz. No desenvolvimento deste trabalho foi realizada a caracterização dos resíduos produzidos no sistema de abate de bovinos em dois ensaios: avaliação dos resíduos sólidos (conteúdo ruminal) e caracterização dos resíduos líquidos (água residuária). No primeiro ensaio, avaliação dos resíduos sólidos, foi realizada a compostagem, durante a qual monitorou-se diariamente a temperatura das leiras confeccionadas com o resíduo de abatedouro de bovinos. Foram avaliadas quatro leiras, divididas em dois ciclos: verão e outono. Para tanto, foram avaliados os teores de sólidos totais (ST) e de sólidos voláteis (SV), carbono orgânico (C) e quantificação dos teores nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg), cobre (Cu), ferro (Fe), manganês (Mn), zinco (Zn) e sódio (Na). Com os resíduos sólidos in natura previamente secos, foram determinados o poder calorífico superior com agregação de sebo, também produzido no processo nas concentrações de 0%, 10%, 20%, 30% e 40%. No segundo ensaio, caracterização dos resíduos líquidos, realizaram-se coletas e análise de amostras compostas de oito pontos do processo de tratamento de resíduos do abatedouro: antes do flotador, depois do flotador, antes da peneira, depois da peneira, efluente do biodigestor 1, efluente do biodigestor 2, afluente das lagoas de polimento e efluentes das lagoas de polimento.
Abstract: Brazil has feed production high potential, but the way used to attend its demand had led to an increasing of generated residues. This fact justifies the recycling practices study like composting and anaerobic biodigestion. More over value aggregation due the residues potentially pollutants transformation to organic fertilizers and energy (biogas) still contributes to an efficient sanitation.'During the experiment the bovine slaughter residues characterization was done in two experiments: solid residues evaluation (ruminal content) and liquid residues characterization (residual water). At first experiment a composting was done using solid residues from cattle slaughter, which the pile temperature was checked daily. Four piles were analyzed, divided in two cycles: summer and autumn. Was analyzed Total Solids (TS) Volatile Solids (VS), Organic Carbon (C), Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Cupper (Cu), Iron (Fe) Manganese (Mn), Zinc (Zn), and Sodium (Na). With in natura residues priory dried, superior calorific power was determined adding fat also produced in the slaughtering process, at 0%, 10%, 20%, 30% and 40% concentrations. The second experiment was done collecting eight small samples per sample at the residue treatment process: before floater, after floater, before sieve, after sieve, biodigestor effluent 1, biodigestor effluent 2, polishing pond affluent, and polishing pond effluent. TS, VS, pH, Chemical Oxygen Demand, (COD) Biochemical Oxygen Demand (BOD), N, P, K, Ca, Mg, Co, Fe, Cu, Zn, Mn elements quantification plus affluent and polish pond effluent Na and Ni content. Viable helminth eggs, Salmonella sp., total and fecal coliform were analyzed in the polish pond affluent and effluent. About the autumn compost piles, they had 10% more volume reduction than the summer ones. The average temperatures were 40ºC during summer and 33ºC during autumn.
Mestre

La indústria càrnia genera enormes quantitats de deixalles, que s'han de tractar i gestionar adequadament per evitar problemes ambientals i de salut. El reciclatge de residus i subproductes animals en productes de valor afegit podria ajudar a revertir aquest problema. Per tant, diversos enfocaments han estat adaptats per la ciència i la tecnologia, acoblant-los amb els coneixements del mercat, la legislació i els consumidors per a la valorització amb èxit d'aquests residus en el marc de l'Economia Circular. Aquesta Tesi Doctoral s'enfoca en un residu subestimat i sense explotar produït durant el procés de tractament de subproductes carnis, anomenat fins. Donat el seu alt contingut en lípids i proteïnes, aproximadament del 37 i 46% respectivament, la investigació es va centrar en la recuperació d'aquests components per a futures aplicacions. Es van establir tres etapes principals: 1.a recuperació de la fracció lipídica, 2.a recuperació de proteïnes en forma de hidrolitzats de proteïnes i 3.a aplicacions potencials dels hidrolitzats de proteïnes. En primer lloc, els fins es van sotmetre a cinc mètodes diferents per extreure la fracció lipídica: mètode de Soxhlet, mètode de Folch, extracció amb ciclopentil metil èter, extracció aquosa i extracció enzimàtica aquosa. Després de l'avaluació de les metodologies emprades en termes de rendiment i l'assignació de punts de penalització en base a l'Eco-Scale, es va triar l'extracció aquosa com el mètode més ecològic. Aquest mètode permet superar els principals inconvenients dels mètodes clàssics, com la generació de gran quantitat de residus i les emissions de vapors orgànics. Atès que l'aigua no és un solvent perillós, el greix es va extreure amb èxit i alhora es van obtenir fins parcialment desgreixats (PDF) per a la següent fase. Finalment, la consistència del greix extret es va optimitzar, obtenint un producte semi-sòlid, a punt per a la seva aplicació com a ingredient en l'alimentació animal. En segon lloc, es van utilitzar dues proteases disponibles comercialment, Alcalasa 2.4L i Neutrasa 0.8L, per recuperar la fracció proteica present en els PDF. Es van optimitzar les condicions d'hidròlisi amb l'objectiu de maximitzar el grau d'hidròlisi (DH) i el procés es va monitoritzar mitjançant el reactiu o-ftalaldehid (OPA). El DH màxim assolit amb l'enzim Alcalasa 2.4L va ser 21,4 % en les següents condicions òptimes: ràtio E/S 5%, pH 8, temperatura 55 °C y temps 24 h. L'enzim Neutrasa 0.8L va exhibir una menor eficiència en la hidròlisi de les proteïnes presents en els PDF i, per tant, una menor recuperació de proteïna. Després de l'optimització de quatre variables (ràtio E/S, pH inicial, temperatura i temps) a través de la metodologia de superfície de resposta (RSM), el DH màxim aconseguit va ser 7,2% en les següent condicions: ràtio E/S 15%, pH inicial 8, temperatura 40 °C i temps 10,5 h. Els perfils peptídics de les hidròlisi es van determinar mitjançant electroforesi (SDS-PAGE) i cromatografia d'exclusió molecular (SEC), mostrant el predomini dels pèptids < 5 kDa en els hidrolitzats obtinguts. La hidròlisi enzimàtica va tenir un gran impacte en el perfil dels compostos volàtils i els grups funcionals. No obstant això, es van observar similituds entre els perfils aminoacídics dels hidrolitzats i els PDF. A més, es van determinar els factors de conversió de nitrogen a proteïna (NPCF) per a les diferents fraccions obtingudes. Finalment, el procés es va escalar (10 vegades), realitzant el pas de matràs a reactor amb èxit, demostrant la viabilitat de l'escalat. Finalment, es va avaluar la utilitat dels hidrolitzats de proteïnes produïts com a font de nitrogen de baix cost. Els hidrolitzats de proteïnes es van incorporar com a font de proteïna en medis de cultius per a microbiologia com a substituts de les peptones, o com a bioestimulants per a plantes. La capacitat dels hidrolitzats de proteïna per sustentar el creixement bacterià va ser excel·lent, fins i tot van superar la capacitat de les fonts de nitrogen comercials en alguns casos. En el cas dels llevats, els efectes van ser dependents de la soca: una de les soques va mostrar un bon rendiment mentre que l'altra va exhibir menor creixement i capacitat de fermentació en presència dels hidrolitzats de proteïna de baix cost. La suplementació amb els hidrolitzats de proteïna obtinguts va tenir un efecte positiu per diverses soques de fongs, millorant la seva capacitat per transformar el 5-hidroximetilfurfural quan aquests microorganismes es van emprar com a biocatalitzadors. Finalment, els hidrolitzats de proteïna no van millorar el creixement de les plantes de tomàquet i rave. En conclusió, la present Tesi Doctoral proporciona una visió de les oportunitats per extreure compostos de valor afegit dels fins a través de pràctiques sostenibles.
La industria cárnica genera enormes cantidades de desechos, que deben tratarse y gestionarse adecuadamente para evitar problemas ambientales y de salud. El reciclaje de residuos y subproductos animales en productos de valor añadido podría ayudar a revertir este problema. Por lo tanto, diversos enfoques han sido adaptados por la ciencia y la tecnología, acoplándolos con los conocimientos del mercado, la legislación y los consumidores para la valorización exitosa de estos residuos en el marco de la Economía Circular. Esta Tesis Doctoral se centra en un residuo subestimado y sin explotar que se produce durante el proceso de tratamiento de subproductos cárnicos, llamado finos. Dado su alto contenido en lípidos y proteínas, aproximadamente del 37 y 46% respectivamente, la investigación se focalizó en la recuperación de estos componentes para futuras aplicaciones. Se establecieron tres etapas principales: 1.a recuperación de la fracción lipídica, 2.a recuperación de proteínas en forma de hidrolizados de proteínas y 3.a aplicaciones potenciales de los hidrolizados de proteínas. En primer lugar, los finos se sometieron a cinco métodos diferentes para extraer la fracción lipídica: método de Soxhlet, método de Folch, extracción con ciclopentil metil éter, extracción acuosa y extracción enzimática acuosa. Después de la evaluación de las metodologías empleadas en términos de rendimiento y la asignación de puntos de penalización en base al Eco-Scale, se eligió la extracción acuosa como el método más ecológico. Este método permite superar los principales inconvenientes de los métodos clásicos, como la generación de gran cantidad de residuos y las emisiones de vapores orgánicos. Dado que el agua no es un solvente peligroso, la grasa se extrajo con éxito mientras se obtuvieron finos parcialmente desgrasados (PDF) para la siguiente fase. Por último, la consistencia de la grasa extraída se optimizó, obteniendo un producto semisólido, listo para su aplicación como ingrediente en la alimentación animal. En segundo lugar, se utilizaron dos proteasas disponibles comercialmente, Alcalasa 2.4L y Neutrasa 0.8L, para recuperar la proteína presente en los PDF. Se optimizaron las condiciones de hidrólisis con el objetivo de maximizar el grado de hidrólisis (DH) y el proceso se monitorizó mediante el reactivo o-ftalaldehído (OPA). El DH máximo alcanzado con la enzima Alcalasa 2.4L fue 21,4 % en las siguientes condiciones óptimas: ratio E/S 5%, pH 8, temperatura 55 °C y tiempo 24 h. La enzima Neutrasa 0.8L exhibió una menor eficiencia en la hidrólisis de las proteínas presentes en los PDF y, por consiguiente, una menor recuperación de proteína. Después de la optimización de cuatro variables (ratio E/S, pH inicial, temperatura y tiempo) a través de la metodología de superficie de respuesta (RSM), el DH máximo alcanzado fue 7,2% en las siguientes condiciones: ratio E/S 15%, pH inicial 8, temperatura 40 °C y tiempo 10,5 h. Los perfiles peptídicos de las hidrólisis se determinaron mediante electroforesis (SDS-PAGE) y cromatografía de exclusión molecular (SEC), mostrando el predominio de los péptidos < 5 kDa en los hidrolizados obtenidos. La hidrólisis enzimática tuvo un gran impacto en el perfil de los compuestos volátiles y los grupos funcionales. Sin embargo, se observaron similitudes entre los perfiles aminoacídicos de los hidrolizados y los PDF. Además, se determinaron los factores de conversión de nitrógeno a proteína (NPCF) para las diferentes fracciones obtenidas. Por último, el proceso se escaló (10 veces), realizando el paso de matraz a reactor exitosamente, demostrando la viabilidad del escalado. Finalmente, se evaluó la utilidad de los hidrolizados de proteínas producidos como fuente de nitrógeno de bajo coste. Los hidrolizados de proteínas se incorporaron como fuente de proteína en medios de cultivos para microbiología como substitutos de las peptonas, o como bioestimulantes para plantas. La capacidad de los hidrolizados de proteína para sustentar el crecimiento bacteriano fue excelente, incluso superaron la capacidad de las fuentes de nitrógeno comerciales en algunos casos. En el caso de la levadura, los efectos fueron dependientes de la cepa: una de las cepas probadas mostró un buen rendimiento mientras que la otra exhibió menor crecimiento y capacidad de fermentación en presencia de los hidrolizados de proteína de bajo coste. La suplementación con los hidrolizados de proteína obtenidos tuvo un efecto positivo para varias cepas de hongos, mejorando su capacidad para transformar el 5-hidroximetilfurfural cuando estos microorganismos se emplearon como biocatalizadores. Finalmente, los hidrolizados de proteína no mejoraron el crecimiento de las plantas de tomate y rábano. En conclusión, la presente Tesis Doctoral proporciona una visión de las oportunidades para extraer compuestos de valor añadido de los finos a través de prácticas sostenibles.
Meat industry generates vast amounts of waste, which must be properly treated and managed to avoid environmental and health concerns. The recycling of animal co- and by-products into added-value products could help turn this problem around. Hence, diverse science and technology-driven approaches have been coupled with market, legislative, and consumer knowledge for the successful valorization of these residues in the frame of Circular Economy. This Ph.D. thesis addresses an underestimated and therefore unexploited waste produced during the rendering process, called fines. Given its high content in lipids and protein, of around 37 and 46%, respectively, the focus was placed on the recovery of these components for further applications. Thus, three main phases were established: 1st fat recovery, 2nd protein recovery as protein hydrolysates, and 3rd potential applications of protein hydrolysates. Firstly, fines were submitted to five different methods to extract the lipidic fraction: Soxhlet method, Folch method, extraction with cyclopentyl methyl ether, aqueous extraction, and aqueous enzymatic extraction. After evaluating the employed methodologies in terms of yield and assigning penalty points based on the Eco-Scale approach, the aqueous extraction was chosen as the greenest method. It allows overcoming the main drawbacks of classical methods, such as the generation of a high amount of waste and organic vapor emissions. Since water is a non-hazardous solvent, the fat was successfully extracted while preparing partially defatted fines (PDF) for the next phase. The consistency of the extracted fat was optimized, obtaining a semi-solid product ready for application as an ingredient in animal feed. Secondly, two commercially available proteases, Alcalase 2.4L and Neutrase 0.8L were used to recover the protein from PDF. Hydrolysis conditions were optimized aiming to maximize the degree of hydrolysis (DH), monitored using the o-phthaldialdehyde (OPA) assay. The maximum DH achieved with Alcalase 2.4L was 21.4% under optimal conditions: E/S ratio 5%, pH 8, temperature 55 °C, and time 24 h. Neutrase 0.8L exhibited lower efficiency in hydrolyzing the protein present in PDF and therefore, lower protein recovery. After optimizing four variables (E/S ratio, initial pH, temperature, and time) through Response Surface Methodology (RSM), the maximum DH achieved was 7.2% with the variables set at: E/S ratio 15%, initial pH 8, temperature 40 °C, and time 10.5 h. Peptides profiles were displayed using electrophoresis (SDS-PAGE) and size exclusion chromatography (SEC), indicating that most of the peptides in the hydrolysates were < 5 kDa. Enzymatic hydrolysis had a significant impact on the volatiles profile and functional groups. However, the amino acid profiles of the hydrolysates and PDF were very similar. In addition, nitrogen-to-protein conversion factors (NPCF) were determined for the different fractions obtained. Lastly, the process was scaled-up (10-fold) from shake-flask to a reactor successfully, demonstrating the feasibility for future scale-up. Finally, the usefulness of the obtained protein hydrolysates as a low-cost nitrogen source was assessed. The protein hydrolysates were incorporated as protein ingredients in microbiological growth media replacing peptones or as biostimulants for plants. The capacity of protein hydrolysates to support bacterial growth was excellent, even outperforming commercial ones in some cases. In the case of yeast, the effects were strain-dependent: one of the tested strains displayed good performance while the other one exhibited lower growth and fermenting capacity in the presence of the low-cost protein hydrolysates. Several fungi strains took advantage of the low-cost protein hydrolysates, improving their capability to transform 5-hydroxymethylfurfural when used as whole-cell biocatalysts. Finally, the protein hydrolysates did not improve tomato and radish plants growth. In conclusion, the present Doctoral Thesis provides an insight into the opportunities for extracting compounds with added-value from fines through sustainable practices.

Naturally occurring plant derived phenols can be degraded through bacteria in swine waste. Chlorinated phenols, which are not naturally present in the environment, are toxic and generated from industrial activities as such petrochemical, pharmaceutical, plastic, rubber, pesticide, iron, steel, paper production, coal conversion, wood preserving, and cellulose bleaching. Large scale coal gasification and carbonization plants are another source of chlorinated phenols. Although not normally present in the environment, chlorinated phenols are structurally similar to many plant derived phenolics. It is our hypothesis that bacteria located in swine wastes may also have the ability to degrade chlorinated phenols. Identifying situations (and organisms) in which degradation of pollutants occurs is important field of research. Experimental work was focused on measuring the degradation of seven chlorinated phenols in swine waste using solid-phase micro-extraction (SPME) and gas chromatography(GC). Microbes in the waste perform respiration or fermentation to obtain the energy they need to carry out their life processes. Fermentation is a process in which electrons are transferred from one organic substrate to another and which results in incomplete degradation of organic compounds. Anaerobic respiration is a process in which organic substrates are degraded completely to CO2, but using substances other than oxygen as the terminal electron acceptor (such as Fe(III), NO3- or SO42-). Anaerobic respiration using these alternative electron acceptors provides an easier pathway for degradation of aromatics than fermentation alone. Usually the abundance of these electron acceptors in waste is low since microbes consume them readily and thus they must be added to the mixture. Our work focused on development of methods for the quantification of chlorinated phenols in swine wastes and results of bioremediation research. In this study, chlorophenols were extracted by SPME and analysed by GC. This research project mainly focused on the anaerobic degradation of chlorophenols in swine waste. It was observed that the decreased concentration of the chlorophenols was likely due to partitioning of the chlorophenols to solids, sticking to glass bottles and by bacteria present in the swine waste. In summary, it was observed that by ANOVA and gas production analysis 2,6-dichlorophenol and 2,4,5-trichlorophenol were likely to be degraded by bacteria present in swine waste.

Integrating an intermittent aeration for the treatment of combined dilute and anaerobic digested swine wastewater in a field swine wastewater treatment system was investigated. Four operations models in term of ratio of aeration to no-aeration of 60:36, 5:1, 4:2 and 3:3 hour were evaluated. At the HRT of 3.2 days and ration of aeration to non-aeration of 3:3, the removal efficiency of BOD5, Total-N, TSS and Total-P of 98.0%, 92.4%, 95.6% and 59.4% could be achieved, respectively. The effluent quality of BOD5, NO3ˉ–N, NH4+–N and TSS concentrations were 35±12mg/l, 2.6±0.8 mg/l, 36±28 mg/l and 78±13 mg/l, respectively. The operational criteria were developed for integrating the intermittent aeration in the swine wastewater treatment system (including anaerobic reactors and sedimentation unit). Economical evaluation of the swine wastewater treatment system integrating the intermittent aeration unit was conducted. It was found that break even point was the operation of 166 pigs if the biogas and stabilized sludge were utilized. If the byproducts were not utilized, the cost of the treatment system are $12.30, $7.92, $7.21, $7.06 and $6.09 for the operation of 300, 1000, 2000, 3000 and 5000 pigs per year, respectively. Integrating the intermittent aeration unit in the swine waste treatment system provides the effective odor control, reduction of energy cost and treated wastewater reuse without creating the deterioration of environmental quality.
Thesis (M. S.)--University of Hawaii at Manoa, 1997.
Includes bibliographical references (leaves 172-180).UHM: Has both book and microform.
U.S Geological Survey/ Water Resource Research Institute (FY 95/96)

Two metabolism trials were conducted with 15 wethers surgically equipped with duodenal and ileal cannulas to study the absorption of P and certain other minerals from swine waste and broiler litter. The effect of source and level of P on rumen cellulytic bacterial populations was also determined. Animals were fed a low P basal diet until serum inorganic P averaged 5.5 mg/dl, then randomly assigned to the following diets: low P basal alone, or supplemented with swine waste, broiler litter, dicalcium phosphate, or soybean meal. Trials consisted of a 7-d preliminary period, a 7-d collection of urine and feces and a 6-d sampling of duodenal and ileal digesta, and feces. Animals fed the waste diets tended to absorb more P than those fed the conventional supplements. Calculated by difference, sheep absorbed more P from swine waste and broiler litter than from dicalcium phosphate and soybean meal (P< .1). Less Ca was absorbed from the waste diets than from the conventionally supplemented diets (P< .05). Expressed as g/d, there was no difference in Mg absorption between waste and conventional diets. Sheep fed waste tended to digest more dry matter and a higher percentage of ADF in the large intestine. Lignin was primarily digested in the large intestine of all sheep. More cellulytic bacteria were isolated from the rumen of sheep fed the supplemented diets (P< .05). Both P intake and P recycling appear to be important influences on cellulytic bacteria in the rumen. Both broiler litter and swine waste appear to be good sources of P and Mg for ruminants.
Ph. D.

Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2017.
Pre-treatment of wastewater such as that from poultry slaughterhouses, which contains fats, oil,and grease (FOG) is necessary prior to the primary biological treatment of the wastewater to meet legislated discharge standards and to prevent environmental pollution. Physico- chemical pre-treatment is often applied to remove FOG in poultry slaughterhouse wastewater (PSW) before biological treatment. These pre-treatment methods, in particular physical pre- treatment systems, use synthetic chemicals, known to cause environmental contamination challenges, with FOG being inefficiently removed in certain instances. Biological techniques such as bio-delipidation using enzymatic catalysis for the pre-treatment of FOG-laden PSW could enhance the efficiency of the downstream biological treatment processes. This research focused on further bio-delipidation of PSW pre-treated with a dissolved air flotation system (DAF) for FOG removal using microbial lipases from bacterial strains isolated from the PSW itself. Bacterial strains (n = 2) isolated from the PSW and screened for their potential to produce lipases were found to have a higher bio-delipidation potential when compared to other isolates (n = 18). Both isolates were identified using 16s rRNA as Bacillus sp., i.e. both Bacillus cereus AB1 (BF3) and CC-1 (B3O). These isolates were used to produce lipases, whereby are sponse surface methodology (RSM) was used to optimise pH (4-8) and temperature (30-60°C) as critical production conditions. achieving an optimum lipase production was achieved, with activity of 11.25 U/mL at 60°C, a pH of8 for BF3, and 15.50U/mL at 45°C and pH of 8.8 for B3O respectively, after 72 hours of bioreactor operation. The enzymes produced from both isolates were partially purified using a Bio-Rad size exclusion chromatography column (Bio-Gel® P-60) prior to use in subsequent experiments. The presence and activity of lipase were further determined using p-nitrophenyl acetate (p- NPA) as a substrate with the functionality of the semi-purified enzymes being characterized by optimizing the conditions in which the enzymes were required to function. Lipase activity was enhanced by Mg2+ while Fe2+, Na+, K+, Ca2+ were observed to have an inhibitory effect on the enzymes from both strains. Similarly, reduced stability of the lipases in organic solvents, namely toluene, methanol, and isopropanol, was also established. Additionally, detergents, Triclosan (TCS) (5-chloro-2-(2,4-dichlorophenoxy-phenol) and trichlorocarbonilide (3,4,4- trichlorocarbonilide)(TCC), usually found in PSW as antimicrobial and disinfectant agents to sanitise poultry product processing facilities, were used assess the activity of the enzyme in their presence at a concentration of 30% (v/v) (although these anti- microbial agents are used in minute quantities in cleaning products). The lipases from isolate BF3 maintained an activity of 91.43% and 81.36% in the presence of TCS and TCC, while that of B3O enzyme had 85.32% and 73.91% acitivity, when compared to the reference (control) experiments. The bio-delipidation efficacy was studied under varying pH and temperature conditions using DAF pre-treated PSW, observing a further removal efficiency of fatty acids from the protein- laden PSW at different pH and temperature. Bio-delipidation was found to be largely influenced by pH, as a pH below 7 and above 10 at 40°-45°C, calculated in the bio- delipidation efficiency reduction to below 50%. The temperature range mentioned, i.e 40°- 45°C, had a positive effect on further deffating of the protein-rich DAF pre-treated PSW, as high removal efficiency was observed at this temperature range. This could be due to the characteristic of the enzymes used,or the formation of stable FOG agglomerates and/oremulsion. Overall, a DAF effluent containing residual FOG and proteins was bio-delipidated effectively using enzymes from the PSW isolates, achieving further removal of FOG and proteins by 64.35% to 80.42%, culminating in tCOD reduction and reduced PSW turbidity, further resulting in improved wastewater quality characteristics meeting disposal standards. This study demonstrated that sequential DAF pre-treated PSW bio-delipidation has the potential to enhance the efficiency of downstream biological anaerobic treatment processes for PSW by further reducing residual FOG from a DAF system.

While commonly thought of as a waste product, food scraps and residuals represent an important opportunity for energy and nutrient recapture within the food system. As demands on production continue to increase, conservation of these valuable resources has become a priority area. In the wake of new legislation in Vermont, Act 148, the Universal Recycling Law, the fate of microbial species in food waste, scraps and residuals is increasingly important. The presence of antimicrobial resistance genes in all types of foods calls for an increased need to estimate risk of antibiotic resistance transfer and maintenance across all segments of food production and distribution systems, from farm to fork. Specifically, the fate of antibiotic resistance genes (ARGs) in these co-mingled food wastes has not been sufficiently characterized; as legislative programs increase in popularity, surveillance of these materials is pressing and should be documented to assess the risk and potential measures for mitigation and management as we approach commercial scales of implementation Previous studies have relied on a combination of targeted techniques, such as 16S rRNA sequencing and qPCR on a specific subset of ARGs; however, these may not cover the full extent of resistance or microorganisms of concern in any given sample. As sequencing technologies improve and costs continue to drop, more comprehensive tools, such as shotgun metagenomic sequencing, can be applied to these problems for both surveillance and novel gene discovery. In this study, we leveraged the increased screening power of the Illumina HiSeq and shotgun metagenomic sequencing to identify and characterize ARGs, microbial communities, and associated virulence factors of food scraps, on-farm composts, and several consumer products. Isolates were also screened for antibiotic resistance to demonstrate the functionality of ARGs identified. The resistome, microbiome, and virulence genes were characterized in all samples. Fifty unique ARGs were identified that spanned 8 major drug classes. Most frequently found were genes related to aminoglycoside, macrolide, and tetracycline resistance. Additionally, 54 distinct virulence factors and 495 bacterial species were identified. Virulence factors were present across the farm setting and mainly included gene transfer mechanisms, while bacteria clustered distinctly into site and farm, as well as separate on farm niches. The relationship between these categories was also assessed by both Pearson correlation and co-inertia analysis, with the most significant relationship being between ARGs and virulence factors (P = 0.05, RV = 0.67). While limited in this study, these patterns reinforce the finding that spread of antibiotic resistance genes may be dependent on the virulence factors present enabling transfer, rather than total microbial community composition.

The aim of this study was to develop improved methods to detect viable Coxiella burnetii in wastes from livestock production. The impetus for this work arose because there is a significant risk of infection for humans attributed to contact with waste products from the livestock production industry. This situation is further compounded by the lack of suitable tools to detect viable C. burnetii in these wastes. In addition, effective disinfection strategies for livestock wastes are also required to reduce the risk of infection with C. burnetii for individuals that come into contact with these waste products. A quantitative real-time PCR system (qPCR) with high sensitivity and specificity was developed to detect the C. burnetii in environmental samples associated with domestic ruminants and native Australian marsupials. Different detection chemistries and procedures were evaluated based on their sensitivity, specificity and reproducibility. Overall it was found that the TaqMan PCR targeting the IS1111a locus provided the most sensitive and reproducible test. The Geneworks PowerSoil(tm) DNA isolation kit provided the best compromise between reproducibility and recovery of DNA from livestock wastes. When combined, the IS1111a TaqMan qPCR and Geneworks PowerSoil DNA Extraction Kit provided a test which was capable of detecting as few as two C. burnetii genome equivalents in 0.2g of soil or faeces. Coxiella burnetii has been shown to display extreme resistance to environmental exposure. Therefore, assessment of the viability of the organism in environmental matrices is more useful for risk assessment programs than detection of DNA alone. A quantitative reverse transcriptase PCR was developed that was able to detect viable C. burnetii cells in soil. The sensitivity of the assay was enhanced by heat-treating the soil samples prior to extraction of RNA. The factor most often associated with transfer of C. burnetii to humans is exposure to livestock or their waste. Therefore, decontamination of waste from livestock production industries is a key factor in preventing outbreaks of Q fever. A system was developed to determine the efficacy of various disinfectant treatments against the environmental pathogen C. burnetii. Treatments evaluated included sodium hypochlorite, ozone, ultraviolet light, peracetic acid (PAA), and Virkon S®. Sodium hypochlorite at a concentration of 0.1 mM reduced the infectivity of C. burnetii by over 92% while treatment with the same sodium hypochlorite concentration in wastewater showed significantly reduced efficacy. Despite this reduced potency, sodium hypochlorite is still useful for control of C. burnetii in the liquid waste of animal production. Commercially available ELISA and CFT assays exist for ruminants but there are no immunological tests available for detecting C. burnetii in marsupials even though Australian marsupials are known to be susceptible to C. burnetii. An indirect ELISA for detecting anti-Coxiella antibodies in kangaroos was developed. Paired serum and faecal samples were taken from 379 ruminants from Western Australia and the serum was tested with a commercially available ELISA and the complement fixation test while the faeces was tested using the qPCR developed during this study. Paired serum and faecal samples were taken from 343 kangaroos from WA and were tested with the antibody-ELISA developed during this study and by qPCR. A very low prevalence of anti-Coxiella antibodies was observed in the ruminants sampled and results from immunological tests correlated poorly with qPCR data. The development of an ELISA for use with kangaroo serum was problematic because of the lack of reference sera from animals known to be infected with C. burnetii. Despite this results from the ELISA developed suggested that the apparent seroprevalence in the WA animals surveyed was approximately 34%. Results from testing kangaroo faeces with the qPCR correlated poorly with the results from the antibody-ELISA. These data suggest that kangaroos may be a significant reservoir of C. burnetii in Western Australia and due to cohabitation of kangaroos and domestic ruminants, may provide a link between the wildlife and domestic cycles of C. burnetii.

The aim of this study was to develop improved methods to detect viable Coxiella burnetii in wastes from livestock production. The impetus for this work arose because there is a significant risk of infection for humans attributed to contact with waste products from the livestock production industry. This situation is further compounded by the lack of suitable tools to detect viable C. burnetii in these wastes. In addition, effective disinfection strategies for livestock wastes are also required to reduce the risk of infection with C. burnetii for individuals that come into contact with these waste products. A quantitative real-time PCR system (qPCR) with high sensitivity and specificity was developed to detect the C. burnetii in environmental samples associated with domestic ruminants and native Australian marsupials. Different detection chemistries and procedures were evaluated based on their sensitivity, specificity and reproducibility. Overall it was found that the TaqMan PCR targeting the IS1111a locus provided the most sensitive and reproducible test. The Geneworks PowerSoil(tm) DNA isolation kit provided the best compromise between reproducibility and recovery of DNA from livestock wastes. When combined, the IS1111a TaqMan qPCR and Geneworks PowerSoil DNA Extraction Kit provided a test which was capable of detecting as few as two C. burnetii genome equivalents in 0.2g of soil or faeces. Coxiella burnetii has been shown to display extreme resistance to environmental exposure. Therefore, assessment of the viability of the organism in environmental matrices is more useful for risk assessment programs than detection of DNA alone. A quantitative reverse transcriptase PCR was developed that was able to detect viable C. burnetii cells in soil. The sensitivity of the assay was enhanced by heat-treating the soil samples prior to extraction of RNA. The factor most often associated with transfer of C. burnetii to humans is exposure to livestock or their waste. Therefore, decontamination of waste from livestock production industries is a key factor in preventing outbreaks of Q fever. A system was developed to determine the efficacy of various disinfectant treatments against the environmental pathogen C. burnetii. Treatments evaluated included sodium hypochlorite, ozone, ultraviolet light, peracetic acid (PAA), and Virkon S®. Sodium hypochlorite at a concentration of 0.1 mM reduced the infectivity of C. burnetii by over 92% while treatment with the same sodium hypochlorite concentration in wastewater showed significantly reduced efficacy. Despite this reduced potency, sodium hypochlorite is still useful for control of C. burnetii in the liquid waste of animal production. Commercially available ELISA and CFT assays exist for ruminants but there are no immunological tests available for detecting C. burnetii in marsupials even though Australian marsupials are known to be susceptible to C. burnetii. An indirect ELISA for detecting anti-Coxiella antibodies in kangaroos was developed. Paired serum and faecal samples were taken from 379 ruminants from Western Australia and the serum was tested with a commercially available ELISA and the complement fixation test while the faeces was tested using the qPCR developed during this study. Paired serum and faecal samples were taken from 343 kangaroos from WA and were tested with the antibody-ELISA developed during this study and by qPCR. A very low prevalence of anti-Coxiella antibodies was observed in the ruminants sampled and results from immunological tests correlated poorly with qPCR data. The development of an ELISA for use with kangaroo serum was problematic because of the lack of reference sera from animals known to be infected with C. burnetii. Despite this results from the ELISA developed suggested that the apparent seroprevalence in the WA animals surveyed was approximately 34%. Results from testing kangaroo faeces with the qPCR correlated poorly with the results from the antibody-ELISA. These data suggest that kangaroos may be a significant reservoir of C. burnetii in Western Australia and due to cohabitation of kangaroos and domestic ruminants, may provide a link between the wildlife and domestic cycles of C. burnetii.

Two experiments were conducted with caged layer waste. In the first experiment fresh waste was treated with: no additive, 2% formaldehyde, 3% sodium metabisulfite, 1% formaldehyde and 2% propionic acid, 3% formic and 2% propionic acids and stored in polyethylene lined 208 liter metal drums. In experiment II waste treated with 2% formaldehyde, 1 % formaldehyde and 2% prop ionic, 3 % formic and 2% propionic (w/w), stored for at least 42 d, used in a metabolism trial as N supplements to a basal diet fed to sheep. The formaldehyde, formaldehyde/propionic and formic/propionic treatments eliminated the bacterial decomposition of the waste and no undesirable fermentation was observed on the stored material. Waste treated with no additive or sodium metabisulfite underwent putrefaction. Nitrogen supplementation of a basal diet with treated caged layer wastes improved apparent digestibility of crude protein and N retention in sheep fed these diets. Supplementation of a basal diet with chemically treated caged layer waste improves the nutritional value of the diet which suggests that caged layer waste is efficiently utilized as a N source by ruminants when used as a protein supplement.
Master of Science

Swine production represents approximately 40% of the world's meat production, and swine wastes contain high concentrations of organic matter, nitrogen (N) and phosphorus (P). Swine production is intensifying as meat demand increases and concentrated animal feeding operations (CAFOs) are becoming increasingly common, making it difficult to treat the waste generated. A system for holistic treatment of swine waste produced in CAFOs was investigated in this study that sustainably generates energy and recovers N and P as saleable fertilizers. The system uses anaerobic digestion (AD) for methane production and solids stabilization, followed by precipitation of struvite (MgNH4PO4*6H2O) and recovery of N by ion exchange onto natural zeolites. This process is expected to mitigate both eutrophication of receiving waters and greenhouse-gas emissions while generating products that meet agronomic nutrient demands; however, the economic and environmental sustainability remains unknown. The objectives of this study were to: (1) evaluate water quality and the fate of nutrients and ions in each step in the proposed system through pilot and bench scale experiments, (2) evaluate content/quality of struvite precipitates formed in wastewater treatment processes, (3) assess basic composition of zeolite materials that are being considered for use as IX materials, (4) quantify the environmental impact of the proposed system, and (5) estimate the economic benefits and costs of the proposed system. The results of a bench scale evaluation of the system show that although water quality greatly improves throughout the treatment process, the effluent water quality has high concentrations of COD (2,803 mg O2/L) and E. coli (106.3 CFU/100ml). This limits reuse options for the reclaimed water, however a variety of on-farm applications may be suitable. During struvite precipitation, the recovery efficiency of SRP was 87% (60 mg/L recovered); however, although measurements that take into account P in suspended solids show a lower recovery efficiency, they also show higher mass recovery (77% efficiency, 66 mg/L recovered). N recovery during struvite precipitation showed a similar trend, with 49% of TN and 7% of NH4-N being recovered. Struvite recovery can only occur from NH4-N and soluble reactive P. The additional recovery observed is likely due to adsorption of the nutrients onto the precipitate. Therefore, to accurately measure and report recovery, measurements of N and P that take into account suspended solids should be used. In most wastes, magnesium is the limiting constituent for struvite formation, but for swine AD effluents, P is the limiting constituent. Therefore, a higher soluble P concentration would increase recovery potential. The majority of the remaining N and P as well as a significant amount of potassium (K) were recovered during IX. Six struvites from commercial processes as well as our bench-scale experiments were assessed and compared by X-ray diffraction, SEM imaging, and SEM-EDX scans. All samples were confirmed as struvite by XRD, however they varied widely in crystal size and shape. The elemental composition of the samples was similar; however, struvite formed from phosphate mining waste had higher amounts Mg and P, indicating more pure struvite formation. The presence of impurities in some samples was likely due to the reactor design and solids separation methods. XRD was also used to confirm the identity of zeolites. Three clinoptilolites had similar crystal size and elemental composition except for Zeosand [reg] which showed a surface roughness, which likely contributes to higher cation exchange capacity. Chabazite has smaller crystal size and larger pores than clinoptilolite, which also likely contributes to its higher capacity. Life cycle assessment (LCA) was used to evaluate the environmental sustainability of the system and the results suggested that environmental benefits were provided across almost all impact categories. Two alternatives for raising the pH in struvite precipitation (NaOH addition vs. aeration) and two alternatives for zeolite IX materials (chabazite vs. clinoptilolite) were assessed, but there were negligible differences between alternatives. The system was also assessed at a medium and large scale, and the large scale was more environmentally friendly across all categories. Operational impacts were significantly greater than construction impacts; therefore, the environmental impact of the system can be accurately assessed by only including operation. A life cycle cost assessment (LCCA) was also performed on the system and showed a payback period of 39 years for a medium sized system and 15 years for a large size. This, however, is when compared to a "business-as-usual" scenario and does not consider renewable energy credits or government grants. Furthermore, although a larger system is more economically beneficial, this must be balanced with quality of animal care. From a cost standpoint, IX recovery using chabazite is not recommended and struvite precipitation using aeration is more economically beneficial than NaOH addition.

Ever since 1976, livestock farmers in Fiji have been intrigued about biogas digesters as an animal waste management measure, but the concept has never evolved into one that is sustainable. Renewed interest came in 1997 after a better Chinese Modified Dome (CMD) design was established, with this came government funding, however by 2002, some failure was also observed. This study set out to investigate the reasons why biogas digesters have never been established as a sustainable concept, its effectiveness as an animal waste management tool and what changes if any, can be made to try and influence the further development of the concept in Fiji. In order to achieve the objectives, which were simply obtaining the answers to the questions presented above, several different approaches had to be followed. This study was the first on biogas digesters in Fiji and it was unique in the sense that the major component dealt with the social aspects of farmers in relation to their biogas digesters. Basically the study was carried out in two parts - desktop studies and field studies. Desktop studies were done to better understand the situation while the field studies included semi-structured interviews with the farmers as well as the collection of biophysical data. Twelve outcomes are presented in chapter 7 of this paper. Two in particular are the improvement of construction and maintenance, which can only come about through training. The research questions are also answered in chapter 7, with recommendations put forward on possible directions to take in terms of trying to influence the development of the concept in Fiji
Master of Science (Hons)

Ever since 1976, livestock farmers in Fiji have been intrigued about biogas digesters as an animal waste management measure, but the concept has never evolved into one that is sustainable. Renewed interest came in 1997 after a better Chinese Modified Dome (CMD) design was established, with this came government funding, however by 2002, some failure was also observed. This study set out to investigate the reasons why biogas digesters have never been established as a sustainable concept, its effectiveness as an animal waste management tool and what changes if any, can be made to try and influence the further development of the concept in Fiji. In order to achieve the objectives, which were simply obtaining the answers to the questions presented above, several different approaches had to be followed. This study was the first on biogas digesters in Fiji and it was unique in the sense that the major component dealt with the social aspects of farmers in relation to their biogas digesters. Basically the study was carried out in two parts - desktop studies and field studies. Desktop studies were done to better understand the situation while the field studies included semi-structured interviews with the farmers as well as the collection of biophysical data. Twelve outcomes are presented in chapter 7 of this paper. Two in particular are the improvement of construction and maintenance, which can only come about through training. The research questions are also answered in chapter 7, with recommendations put forward on possible directions to take in terms of trying to influence the development of the concept in Fiji

Thesis (M. Sc.) (Hons) -- University of Western Sydney, 2005.
" A thesis presented to the School of Environment and Agriculture, University of Western Sydney, in fulfilment of the requirements for the degree of Master of Science (Honours)." Includes bibliography : leaves 165 -175, and appendices.

Increased adoption of compost bedded pack dairy barns (CBP), a relatively new housing and manure handling strategy, warrants study to facilitate proper use of CBP waste as a soil amendment. This study: 1) characterized in situ nutrient content and availability of CBP waste in terms of nitrogen (N) and phosphorus (P); 2) examined the decomposition of surface-applied CBP waste compared to an alternative processed solid waste amendment; 3) examined nutrient dynamics of incorporated CBP waste in high and low soil test phosphorus (STP) environments. Quick anaerobic mineralization assays revealed that bed management affects nutrient content and availability of CBP waste. A Fall surface-applied litter bag study showed that different particle sizes of CBP waste and a biosolid decomposed at similar rates. The biosolid had greater nutrient density and availability, but the decomposition was similar to CBP waste in terms of mineralization dynamics. Aerobic mineralization of CBP waste in high and low STP soils amended on a uniform P basis was compared with fresh manure. In general, CBP increased STP more and yielded more plant available P than fresh manure. These studies provide recommendations for CBP management and further study to ensure the proper land application of CBP waste.