Browsing by Subject "Animal feed"
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Item Development of an effective swine manure-based algal cultivation system for biofuel & animal feed production and wastewater treatment(2013-03) Hu, BingMicroalgae have great potential to replace current crop feedstocks for biofuel and animal feed production. However, the algal industry is still far from being economically applicable. The dissertation was inspired by the idea of integrating algal biomass production and wastewater treatment. The overall objective of the study was to develop an effective algal cultivation system in which inorganic nutrients and organic substances in swine manure could be utilized by robust microalgae strains for the production of algal biomass with high lipids or protein contents. The first step in the study was bioprospecting for mixotrophic microalgae strains that adapted well to diluted swine manure. Through the multi-step screening strategy, two locally isolated microalgae strains, UMN271 and UMN266, were found to be facultative heterotrophic, manure-tolerant, and obviously robust in the algae storage including 98 UTEX strains and 50 indigenous strains. The two strains were identified as Chlorella sp. and Hindakia sp., respectively, through morphological observation and genetic identification, and were utilized for further studies in the dissertation. Since algae growth on highly diluted swine manure was still relatively low, a second step in the study was to assess the limiting factors of using anaerobically decomposed swine manure as nutrient supplement for algae cultivation. In the study, Chlorella sp. (UMN271) and Hindakia sp. (UMN266) were used to investigate the effects of two potential factors, which were trace elements and carbon compounds in swine manure, on algal growth and waste nutrient recovery. The results indicated that the algal growth and nutrient removal rates were independent of trace metal content in diluted swine manure, but were significantly improved when the initial liquid COD content in swine manure was high. Moreover, it was demonstrated that Chlorella sp. (UMN271) was able to utilize acetic, propionic and butyric acids, the main water-soluble organic carbon compounds in digested swine manure, for algal growth, lipid production, and waste nutrient removal. Therefore, it was considered that algal growth in highly diluted swine manure was limited by the deficiency of volatile fatty acids (VFAs). The third step was to modify anaerobic digestion process for liquid swine manure (LSM) rich in VFAs, so that the liquid effluent could be more suitable than the conventionally decomposed LSM effluent as nutrient for the cultivation of Chlorella sp. (UMN271). The results showed that the modified acidogenic digestion successfully promoted VFA concentrations in swine manure. The obtained acidogenically digested LSM supported the growth of Chlorella sp.(UMN271) in a 5-day batch experiment with higher algal growth rates and fatty acid contents in comparison with those on the conventionally decomposed LSM. High removal efficiencies on water-soluble nutrients, including COD, PO4-P, TN and NH3-N, were also observed for the raw, acidogenically digested manure sample (58.02%, 44.74%, 31.58%, and 44.73%, respectively). Finally, the fatty acid profile analysis showed that harvested algal biomass could be used as feedstock to produce high-quality biodiesel. In the fourth step, central composite design (CCD) was used to investigate the influences of two key parameters, namely wastewater dilution rate (DR) and hydraulic retention time (HRT), on algal biomass productivity and waste nutrient removal rates. According to the response surface analyses of the CCD results, statistically valid quadric models for the response variables, including algal biomass productivity and the liquid nutrient removal rates including COD, PO4-P, TN and NH3-N, were obtained. The regression analyses illustrated that both DR and HRT had significant influences on the five response variables. The optimal conditions estimated from the significant second-order quadratic models (p<0.05) were 8-fold DR and 2.26-d HRT. The final step was the development of an effective algal cultivation system for the semicontinuous production of algal biomass and waste nutrient removal. In the study, the predicted optimal conditions were applied in a bench-scale multi-layer photobioreactor (PBR) for algae growth on acidogenically digested swine manure. The 17-day semicontinuous cultivating experiment achieved high and stable algal productivity and nutrient removal rates, which fitted the predictive models well. Moreover, relatively high and stable protein and lipid contents (58.78% and 26.09% of the dry weight, respectively) were observed for the harvested algal sample, indicating the suitability of the algal biomass as ideal feedstock for both biofuel and animal feed production.Item Efficacy of prebiotics and probiotics on growth performance in poultry: A protocol for a systematic review(2020) Hwang, Haejin; Miller, Elizabeth A.; Johnson, Abigail; Valeris-Chacin, Robert; Nault, Andre J.; Singer, Randall S.; Johnson, Timothy J.The use of prebiotics and probiotics as dietary additives in poultry has been practiced widely as an alternative to antibiotics and to support gut health. Despite the wealth of products available, there is currently a lack of clear scientific evidence that the use of prebiotics and probiotics beneficially impact growth performance in poultry. The aim of this protocol paper is to document the process of a systematic review addressing the following review question: Does oral administration of a prebiotic (defined as dietary fiber, dietary carbohydrates, oligosaccharides, or yeast cell wall) or probiotic (defined or undefined single or mixed cultures of living bacteria, fungi, and/or yeast) provide beneficial effects on growth performance in broiler chickens and turkeys? The proposed systematic review will provide evidence on the effectiveness of prebiotics and probiotics for enhancing growth performance in poultry, and will help to alleviate high skepticism, criticism, and confusion over the use of prebiotics and probiotics in poultry among poultry producers.Item Nutrient Transformations by Microorganisms for Novel Animal Feed Ingredients(2018-02) Barnharst, TannerThe world population will reach 9 billion people by 2050 or sooner and as a result, we must produce 70% more food than we currently are. This food challenge lends itself to many innovative solutions. In this thesis, the use of microorganisms to produce higher value animal feeds is examined. The current challenge in intensive aquaculture is to control the level of nutrient pollutants in the wastewater and provide sustainable sources of proteins for feed. A synthetic lichen type biofilm was developed to have the fungus Mucor indicus and the microalga Chlorella vulgaris grow together on a polymer matrix referred to as a “mycoalgae” biofilm. When the biofilm grows, it takes up phosphorus and nitrogen compounds and converts them to proteins and other cellular products. It cleans the water from nutrient pollutants as the algae are attached to the biofilm leaving purified water at the end of the process. Under 25 mg L-1 total ammonia-N (TAN) conditions, the biofilm reduced TAN to undetectable limits within 48 h with over 69% of the TAN reduction taking place by 24 h. The biofilm reduced levels of phosphate-P from 15 mg to undetectable limits within 24 h. Under the same conditions, 860 mg of dry mycoalgae biomass was generated at the end of the process on 16 cm2 of mesh and 100 ml of culture media. This process allows for easy harvesting of the algae with no energy intensive process of separating the algae from the supernatant. The generated biofilm is composed of two organisms that have been shown to positively aid fish health when included as a feed supplement. Secondary Fermentation of Corn Ethanol Co-Products for improved Amino Acid Qualities In 2016, 5.28 billion bushels of corn were used to produce about 14.79 billion gallons of ethanol in the United States. As a result, about 36 million tons of Dried Distillers Grains with Solubles (DDGS) were manufactured and fed to livestock 1. DDGS are a common feed supplement in cattle rations as it is inexpensive and has positive feeding characteristics. One of the drawbacks of DDGS is that it is lacking in in key amino acids such as tryptophan, arginine, and lysine. Historically these amino acids have been supplemented by external addition of feed grade amino acids to rations. The research carried out attempts to fortify DDGS with higher amounts of key amino acids through secondary fermentation of Wet Distillers Grains by fungi. When cultured on WDG the fungi consumes carbohydrates, which are unavailable to livestock, and converts the carbohydrates to proteinaceous biomass, which serves to close the amino acid gap in corn ethanol co-products. The fungi used are Generally Regarded as Safe (GRAS) and have been used to produce feed ingredients historically. Because of the research, more sustainable forms of animal feed will be produced due to the improved feeding value of the co-productsItem Thirty-eighth Minnesota Nutrition Conference, Bloomington, Minnesota, September 19-20, 1977.(University of Minnesota, Department of Animal Science, 1977-09)