No description available.

Doctor of Philosophy / Department of Animal Sciences and Industry / James S. Drouillard / Four studies evaluated effects of dry distillers grains with solubles (DDGS) containing high S concentrations on feedlot performance, ruminal fermentation, and diet digestibility by finishing cattle. Trial 1 used finishing steers fed diets based on steam-flaked corn (SFC) or dry-rolled corn (DRC), and containing 30% DDGS (DM) with 0.42% S (0.42S) or 0.65% S (0.65S). No interaction (P ≥ 0.15) between dietary S and grain processing occurred, but feeding 0.65S decreased DMI (P < 0.001) and ADG (P = 0.006) by 8.9% and 12.9%, respectively, whereas G:F was unaffected by S concentration (P = 0.25). Steers fed 0.65S had 4.3% lighter HCW (P = 0.006), lower KPH (P = 0.009), and lower yield grades (P = 0.04) than steers fed 0.42S. Concentration of H2S was inversely related (P ≤ 0.01) to ADG (r = -0.58) and DMI (r = -0.67) in cattle fed SFC, and DMI (r = -0.40) in cattle fed DRC. Trial 2 used the same treatments as in the first stud, and investigated ruminal fermentation characteristics and diet digestibility by feedlot cattle. Feeding 0.65S increased ruminal pH (P < 0.05), but decreased total VFA concentrations (P = 0.05). Steers fed 0.65S had greater ruminal NH3 concentrations (P < 0.01) than steers fed 0.42S. The magnitudes of these effects were greater in steers fed DRC than in steers fed SFC (interaction, P < 0.01). Feeding 0.65S yielded greater apparent total tract digestibilities of DM (P = 0.04) and ether extract (P = 0.03). The 3rd study evaluated effects of in vitro S titration (0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6% of DM) in substrates based on ground corn and DDGS (GC-DDGS) or ground corn with urea and soybean meal (GC-SBM). Concentrations of NH3, total VFA, IVDMD, in vitro gas production, and gas composition were unaffected by S (P > 0.05) or by the S × substrate interaction (P > 0.05). Study 4 evaluated cattle feedlot performance when exposed to DDGS containing high S levels, either continuously or intermittently. Treatments were chronic high S (CHS; 0.60% DM), chronic intermediate S (CIS; 0.50% DM), and sporadic intermediate S (SIS; oscillating from 0.40 or 0.60% S DM basis). Steers fed CHS had 11.2 and 6.1% less (P < 0.05) DMI than steers fed CIS and SIS, respectively, but there were no treatment effects on ADG, G:F, or carcass characteristics (P > 0.10). These studies suggest that changes in cattle performance and digestibility associated with high S are primarily attributable to decreased DMI, but infrequent exposure to high levels is no more harmful than continuous exposure.

Master of Science / Department of Agricultural Economics / Arlo Biere / A major story in the recent history of US agriculture is the evolution and growth of the ethanol industry. A crucial factor in the profitability of an ethanol plant is the choice of its fixed location, as this has implications in the transportation costs associated with the acquisition of grain and sale of distiller’s grains. When the industry was in its infancy, where to locate, often, was based on strictly local factors. Primary considerations were local availability of grain and producer and community investment interests. Today, the ethanol industry is more mature and consolidated. As such, investment criteria have broadened from a localized to a total systems perspective. The focus of this study was to analyze construction, abandonment, and expansion of plant locations in ethanol producing regions, and the effects of regional transportation costs on the geographic growth of the industry. Comparison to previous research provided the basis to evaluate industry change. Current ethanol plant locations and their capacities were complied and compared with earlier data to identify plant exits, expansions and new construction. Aggregating those plant capacities by USDA crop reporting districts, feedstock consumption by biorefineries were calculated by crop reporting district, as was livestock feed demand from livestock numbers. Those data along with coarse grain production by crop reporting district were used to calculate excess feedgrain demand (supply) by region. Those regional data were used to construct linear programming network-flow models for the transportation of feedstock and for DDGS, respectively. Two models were used; the first was used minimize the interregional cost to transport feedstocks from excess supply regions to excess demand regions. The second was used to minimize the interregional cost to transport DDGS from excess supply regions to excess demand regions. These regional transportation costs were combined to find the total interregional transport by crop reporting district. Differences in such interregional transport costs affect the competitiveness of plants across crop reporting districts and should affect the strategic position of each plant location. Current plant locations and transportation cost results were compared with those from previous research and, with additional consideration to changes in production factors, provided further understanding of the recent growth and development of the ethanol industry.

Bio fuels are made from an extensive selection of fuels derived from biomass, including wood waste, agricultural wastes, and alcohol fuels. As a result of increased energy requirements, raised oil prices, and concern over greenhouse gas emissions from fossil fuels, bio fuels are acquiring increased public and scientific attention. The ethanol industry is booming and during the past several years, there has been an increase in demand for fuel ethanol and use of its co-products. To increase potential revenues from ethanol processing and its utilization, extensive research is proceeding in this field. In Western Canada, wheat is the primary raw material used in the production of ethanol by fermentation and distillers dried grains with solubles (DDGS) are one of the major co-products produced during this process. At present, the DDGS are generally sold as animal feed stock but with some alteration they could be used in other useful areas.<p> Densification of biomass and use of it for fuel like wood pellets, hay briquettes, etc. have been studied for many years and have also been commercialized. In this thesis, pellets made from distillers dried grains have been investigated. DDGS were obtained from Noramera Bioenergy Corp. and Terra Grain Fuels Ltd. Before transforming them into pellets, they were characterized on the basis of physical and chemical properties. A California pilot-scale mill (with and without steam conditioning) was used for pelleting the distillers grains with solubles.<p> A full factorial design with two levels of moisture content (i.e., 14 and 15.5% (w.b.)), hammer mill screen size (i.e., 3.2 and 4.8 mm) and temperature (i.e., 90 and 100°C) was used to determine the effects of these three factors on the pellet properties made from Noramera Bioenergy Corp., without steam conditioning. Different levels of moisture content were used for the pellets made from Terra Grain Fuels Ltd. (i.e., 11.5 and 13.09% (w.b.)), with steam conditioning. The initial moisture contents of the DDGS were 12.5 and 13.75% (w.b.) from Noramera and Terra Grain, respectively. The moisture content of DDGS grinds ranged from 11.6 to 12.03% (w.b.) for the Noramera samples, and from 11.5 to 13.09% (w.b.) for Terra Grain DDGS. The moisture content decreased with a decrease in the hammer mill screen size.<p> The use of a smaller screen size achieved an increase in both the bulk and particle densities of the DDGS. The coefficient of internal friction was almost the same for both samples but cohesion was higher in Noramera samples (8.534 kPa). The DDGS obtained from Noramera Bioenergy Corp. contained dry matter (91.40%), crude fibre (4.98%), crude protein (37.41%), cellulose (10.75%), hemi-cellulose (21.04%), lignin (10.50%), starch (3.84%), fat (4.52%) and ash (5.16%); whereas the samples obtained from Terra Grain Fuels contained dry matter (87.69%), crude fibre (7.33%), crude protein (32.43%), cellulose (10.81%), hemi-cellulose (27.45%), lignin (4.37%), starch (4.18%), fat (6.37%) and ash (4.50%).<p> The combustion energy of the Noramera samples was 19.45 MJ/kg at a moisture content of 8.6% (w.b.) whereas the combustion energy of Terra Grain samples was 18.54 MJ/kg at 12.31% (w.b.) moisture content.<p> The durability of the pellets increased as the screen size decreased which is likely due to the fact that a smaller screen size produces more fine particles. This fill voids in the pellets and, hence, makes them more durable.<p> The length of the pellets produced from Noramera DDGS increased with a decrease in moisture content possibly because pellets formed at higher moisture content absorb less moisture. Therefore, the length does not increase as much. Lateral expansion occurred most with higher temperature and lower moisture content and with lower temperature and higher moisture content. The length to diameter ratio of the pellets followed the same trend as the change in pellet length. The length of the pellets produced from Terra Grain also increased with a decrease in moisture content. The lateral expansion increased with increase in screen size and moisture content and also, with decrease in moisture content and increase in temperature. The length to diameter ratio increased with decrease in screen size and moisture content, similar to the change in pellet length. The highest bulk density of Noramera pellets resulted from smaller screen size and lower moisture. The particle density increased with a decrease in screen size and an increase in moisture content. The highest bulk density of Terra Grain pellets occurred with an increase in temperature and decrease in moisture content. The highest particle density occurred with an increase in temperature and decrease in screen size.<p> The pellet hardness increased with a decrease in moisture content and screen size did not have any significant effect. The Terra Grain pellets were harder because they were subjected to steam conditioning. Steam conditioning helps to increase the hardness.<p> The pellet durability increased with a decrease in screen size and increase in moisture content. The steam conditioning also caused the higher durability in the Terra Grain pellets. In terms of moisture absorption, the only significant factor was moisture content. Pellets with lower moisture content absorbed more moisture.<p> The ash content values of pellets were higher in Noramera samples than in Terra Grain samples because of high moisture content in Noramera samples. The combustion energy of the Noramera pellets was higher than the Terra Grain pellets because of the high percentage of dry matter and lignin present in Noramera samples. The emission results for both the sample pellets were similar. When the DDGS pellets were compared to wood pellets, emission of nitrous oxide was lower for wood whereas, carbon dioxide was higher.

The main objective of this project was to investigate the effects of the type of dried distillers grains with solubles (wheat DDGS, corn DDGS, and blend DDGS (eg. wheat:corn = 70:30)) and bio-ethanol plant origin on the nutrient variation and availability in ruminants. In addition, DDGS products were studied as opposed to their parental grains. The project was divided into the several following studies. In Study 1, we studied the nutritive value of DDGS products in terms of (1) chemical profiles, (2) protein and carbohydrate sub-fractions associated with different degradation rates, and (3) digestible component nutrients and energy values using the NRC 2001-chemical approach and the in situ assay-biological approach. Also, we tested the validity of acid detergent insoluble crude protein (ADICP) and acid detergent lignin (ADL) to predict the potential degradability of DDGS. Due to starch fermentation in the ethanol process, the chemical components in DDGS became approximately threefold more concentrated than in feedstock grains. Slowly degraded protein (PB3) and unavailable protein (PC) increased in DDGS, indicating a decrease in the overall protein degradability in the rumen. Intermediately degraded protein (PB2) was higher for corn DDGS than for wheat DDGS and blend DDGS (54.2 vs. 27.7 vs. 30.8 %CP), while PB3 was higher for wheat DDGS and blend DDGS (29.9 vs. 51.2 vs. 53.2 %CP). Mainly as a result of differing heat conditions, PC differed significantly between wheat DDGS originated at different bio-ethanol plants (0.7 vs. 7.6 %CP). The prediction of truly digestible CP (tdCP) and NDF (tdNDF) differed between the NRC 2001-chemical approach and the in situ assay-biological approach; however, both approaches reported similar energy values. These values were the highest for corn DDGS (DE3X: 3.9 Mcal kg-1), followed by blend DDGS (DE3X: 3.6 Mcal kg-1), and wheat DDGS (DE3X: 3.4 Mcal kg-1). Corn DDGS was superior to corn, wheat DDGS was similar to wheat and corn, and blend DDGS was similar to corn. No significant differences in energy values were reported between bio-ethanol plants. ADICP was not an accurate indicator of the potential degradability of protein in DDGS samples, while ADL seemed to be an acceptable indicator of the potential degradability of DM (r = -0.87; P<0.01), CP (r = -0.89; P<0.01), and NDF (r = -0.82; P<0.01) in wheat DDGS samples incubated in rumen during 48 h.<p> In Study 2, we studied the ruminal and intestinal digestion profiles and the hourly effective rumen degradation ratios between nitrogen (N) and energy. The results showed a reduction in the effective degradability of DM (EDDM), OM (EDOM) and CP (EDCP) of wheat DDGS relative to wheat; however, corn DDGS remained the same as corn. The effective degradability of NDF (EDNDF) did not vary between the DDGS samples and feedstock grains. Among DDGS types, EDDM ranged from 52.4 to 57.7 %, EDOM from 46.4 to 53.5 %DM, and EDCP from 34.0 to 45.6 %CP, being higher as the proportion of wheat in feedstock increased. No significant differences in EDDM, EDOM, EDCP and EDNDF for wheat DDGS were detected between the different bio-ethanol plants. The hourly effective degradability ratios between N and energy indicated a potential excess of N in rumen when DDGS samples were evaluated as single ingredient. This excess increased as the proportion of wheat in feedstock increased. Estimated intestinal digestibility of rumen bypass protein (IDP) was similar between wheat and wheat DDGS, but higher in corn DDGS than in corn. Blend DDGS had the highest IDP (93.9 %RUP). Due to the significantly different PC sub-fraction found in wheat DDGS originated at the different bio-ethanol plants, a large but numerical difference was detected in IDP (89.4 vs. 75.9 %RUP).<p> In Study 3, we used both the DVE/OEB System and the NRC 2001 Model to reveal the metabolic characteristics of DDGS protein and predict the protein supply to dairy cattle. The two models showed higher protein values (DVE or MP) for DDGS samples than for feedstock grains. The higher IDP for blend DDGS largely contributed to the higher protein value relative to wheat DDGS and corn DDGS (MP: 277 vs. 242 vs. 250 g kg-1 DM). Similarly, protein values differed significantly between the bio-ethanol plants mainly as a result of the numerical but large difference in IDP (MP: 272 vs. 223 g kg-1 DM). According to the two models, the degraded protein balance for DDGS products was higher than in the parental grains. Wheat DDGS showed the highest potential N excess (DBPNRC: 78 g kg-1 DM). For corn DDGS, however, the DVE/OEB System suggested a potential N excess (11 g kg-1 DM) while the NRC 2001 Model exhibited a potential N deficiency (-12 g kg-1 DM). The degraded protein balance for wheat DDGS was similar between the different bio-ethanol plants.<p> In conclusion, the chemical and biological characteristics of DDGS varied among types and between wheat DDGS samples manufactured at the different bio-ethanol plants. Thus, it is inappropriate to assume fixed values for the nutritive value of DDGS without considering factors such as type of grain used and bio-ethanol plant origin. Further research with higher number of samples will help to clarify the use of the chemical profile to predict energy values and the potential degradability of DDGS.

Bio fuels are made from an extensive selection of fuels derived from biomass, including wood waste, agricultural wastes, and alcohol fuels. As a result of increased energy requirements, raised oil prices, and concern over greenhouse gas emissions from fossil fuels, bio fuels are acquiring increased public and scientific attention. The ethanol industry is booming and during the past several years, there has been an increase in demand for fuel ethanol and use of its co-products. To increase potential revenues from ethanol processing and its utilization, extensive research is proceeding in this field. In Western Canada, wheat is the primary raw material used in the production of ethanol by fermentation and distillers dried grains with solubles (DDGS) are one of the major co-products produced during this process. At present, the DDGS are generally sold as animal feed stock but with some alteration they could be used in other useful areas.<p> Densification of biomass and use of it for fuel like wood pellets, hay briquettes, etc. have been studied for many years and have also been commercialized. In this thesis, pellets made from distillers dried grains have been investigated. DDGS were obtained from Noramera Bioenergy Corp. and Terra Grain Fuels Ltd. Before transforming them into pellets, they were characterized on the basis of physical and chemical properties. A California pilot-scale mill (with and without steam conditioning) was used for pelleting the distillers grains with solubles.<p> A full factorial design with two levels of moisture content (i.e., 14 and 15.5% (w.b.)), hammer mill screen size (i.e., 3.2 and 4.8 mm) and temperature (i.e., 90 and 100°C) was used to determine the effects of these three factors on the pellet properties made from Noramera Bioenergy Corp., without steam conditioning. Different levels of moisture content were used for the pellets made from Terra Grain Fuels Ltd. (i.e., 11.5 and 13.09% (w.b.)), with steam conditioning. The initial moisture contents of the DDGS were 12.5 and 13.75% (w.b.) from Noramera and Terra Grain, respectively. The moisture content of DDGS grinds ranged from 11.6 to 12.03% (w.b.) for the Noramera samples, and from 11.5 to 13.09% (w.b.) for Terra Grain DDGS. The moisture content decreased with a decrease in the hammer mill screen size.<p> The use of a smaller screen size achieved an increase in both the bulk and particle densities of the DDGS. The coefficient of internal friction was almost the same for both samples but cohesion was higher in Noramera samples (8.534 kPa). The DDGS obtained from Noramera Bioenergy Corp. contained dry matter (91.40%), crude fibre (4.98%), crude protein (37.41%), cellulose (10.75%), hemi-cellulose (21.04%), lignin (10.50%), starch (3.84%), fat (4.52%) and ash (5.16%); whereas the samples obtained from Terra Grain Fuels contained dry matter (87.69%), crude fibre (7.33%), crude protein (32.43%), cellulose (10.81%), hemi-cellulose (27.45%), lignin (4.37%), starch (4.18%), fat (6.37%) and ash (4.50%).<p> The combustion energy of the Noramera samples was 19.45 MJ/kg at a moisture content of 8.6% (w.b.) whereas the combustion energy of Terra Grain samples was 18.54 MJ/kg at 12.31% (w.b.) moisture content.<p> The durability of the pellets increased as the screen size decreased which is likely due to the fact that a smaller screen size produces more fine particles. This fill voids in the pellets and, hence, makes them more durable.<p> The length of the pellets produced from Noramera DDGS increased with a decrease in moisture content possibly because pellets formed at higher moisture content absorb less moisture. Therefore, the length does not increase as much. Lateral expansion occurred most with higher temperature and lower moisture content and with lower temperature and higher moisture content. The length to diameter ratio of the pellets followed the same trend as the change in pellet length. The length of the pellets produced from Terra Grain also increased with a decrease in moisture content. The lateral expansion increased with increase in screen size and moisture content and also, with decrease in moisture content and increase in temperature. The length to diameter ratio increased with decrease in screen size and moisture content, similar to the change in pellet length. The highest bulk density of Noramera pellets resulted from smaller screen size and lower moisture. The particle density increased with a decrease in screen size and an increase in moisture content. The highest bulk density of Terra Grain pellets occurred with an increase in temperature and decrease in moisture content. The highest particle density occurred with an increase in temperature and decrease in screen size.<p> The pellet hardness increased with a decrease in moisture content and screen size did not have any significant effect. The Terra Grain pellets were harder because they were subjected to steam conditioning. Steam conditioning helps to increase the hardness.<p> The pellet durability increased with a decrease in screen size and increase in moisture content. The steam conditioning also caused the higher durability in the Terra Grain pellets. In terms of moisture absorption, the only significant factor was moisture content. Pellets with lower moisture content absorbed more moisture.<p> The ash content values of pellets were higher in Noramera samples than in Terra Grain samples because of high moisture content in Noramera samples. The combustion energy of the Noramera pellets was higher than the Terra Grain pellets because of the high percentage of dry matter and lignin present in Noramera samples. The emission results for both the sample pellets were similar. When the DDGS pellets were compared to wood pellets, emission of nitrous oxide was lower for wood whereas, carbon dioxide was higher.

The main objective of this project was to investigate the effects of the type of dried distillers grains with solubles (wheat DDGS, corn DDGS, and blend DDGS (eg. wheat:corn = 70:30)) and bio-ethanol plant origin on the nutrient variation and availability in ruminants. In addition, DDGS products were studied as opposed to their parental grains. The project was divided into the several following studies. In Study 1, we studied the nutritive value of DDGS products in terms of (1) chemical profiles, (2) protein and carbohydrate sub-fractions associated with different degradation rates, and (3) digestible component nutrients and energy values using the NRC 2001-chemical approach and the in situ assay-biological approach. Also, we tested the validity of acid detergent insoluble crude protein (ADICP) and acid detergent lignin (ADL) to predict the potential degradability of DDGS. Due to starch fermentation in the ethanol process, the chemical components in DDGS became approximately threefold more concentrated than in feedstock grains. Slowly degraded protein (PB3) and unavailable protein (PC) increased in DDGS, indicating a decrease in the overall protein degradability in the rumen. Intermediately degraded protein (PB2) was higher for corn DDGS than for wheat DDGS and blend DDGS (54.2 vs. 27.7 vs. 30.8 %CP), while PB3 was higher for wheat DDGS and blend DDGS (29.9 vs. 51.2 vs. 53.2 %CP). Mainly as a result of differing heat conditions, PC differed significantly between wheat DDGS originated at different bio-ethanol plants (0.7 vs. 7.6 %CP). The prediction of truly digestible CP (tdCP) and NDF (tdNDF) differed between the NRC 2001-chemical approach and the in situ assay-biological approach; however, both approaches reported similar energy values. These values were the highest for corn DDGS (DE3X: 3.9 Mcal kg-1), followed by blend DDGS (DE3X: 3.6 Mcal kg-1), and wheat DDGS (DE3X: 3.4 Mcal kg-1). Corn DDGS was superior to corn, wheat DDGS was similar to wheat and corn, and blend DDGS was similar to corn. No significant differences in energy values were reported between bio-ethanol plants. ADICP was not an accurate indicator of the potential degradability of protein in DDGS samples, while ADL seemed to be an acceptable indicator of the potential degradability of DM (r = -0.87; P<0.01), CP (r = -0.89; P<0.01), and NDF (r = -0.82; P<0.01) in wheat DDGS samples incubated in rumen during 48 h.<p> In Study 2, we studied the ruminal and intestinal digestion profiles and the hourly effective rumen degradation ratios between nitrogen (N) and energy. The results showed a reduction in the effective degradability of DM (EDDM), OM (EDOM) and CP (EDCP) of wheat DDGS relative to wheat; however, corn DDGS remained the same as corn. The effective degradability of NDF (EDNDF) did not vary between the DDGS samples and feedstock grains. Among DDGS types, EDDM ranged from 52.4 to 57.7 %, EDOM from 46.4 to 53.5 %DM, and EDCP from 34.0 to 45.6 %CP, being higher as the proportion of wheat in feedstock increased. No significant differences in EDDM, EDOM, EDCP and EDNDF for wheat DDGS were detected between the different bio-ethanol plants. The hourly effective degradability ratios between N and energy indicated a potential excess of N in rumen when DDGS samples were evaluated as single ingredient. This excess increased as the proportion of wheat in feedstock increased. Estimated intestinal digestibility of rumen bypass protein (IDP) was similar between wheat and wheat DDGS, but higher in corn DDGS than in corn. Blend DDGS had the highest IDP (93.9 %RUP). Due to the significantly different PC sub-fraction found in wheat DDGS originated at the different bio-ethanol plants, a large but numerical difference was detected in IDP (89.4 vs. 75.9 %RUP).<p> In Study 3, we used both the DVE/OEB System and the NRC 2001 Model to reveal the metabolic characteristics of DDGS protein and predict the protein supply to dairy cattle. The two models showed higher protein values (DVE or MP) for DDGS samples than for feedstock grains. The higher IDP for blend DDGS largely contributed to the higher protein value relative to wheat DDGS and corn DDGS (MP: 277 vs. 242 vs. 250 g kg-1 DM). Similarly, protein values differed significantly between the bio-ethanol plants mainly as a result of the numerical but large difference in IDP (MP: 272 vs. 223 g kg-1 DM). According to the two models, the degraded protein balance for DDGS products was higher than in the parental grains. Wheat DDGS showed the highest potential N excess (DBPNRC: 78 g kg-1 DM). For corn DDGS, however, the DVE/OEB System suggested a potential N excess (11 g kg-1 DM) while the NRC 2001 Model exhibited a potential N deficiency (-12 g kg-1 DM). The degraded protein balance for wheat DDGS was similar between the different bio-ethanol plants.<p> In conclusion, the chemical and biological characteristics of DDGS varied among types and between wheat DDGS samples manufactured at the different bio-ethanol plants. Thus, it is inappropriate to assume fixed values for the nutritive value of DDGS without considering factors such as type of grain used and bio-ethanol plant origin. Further research with higher number of samples will help to clarify the use of the chemical profile to predict energy values and the potential degradability of DDGS.

Four trials were conducted to evaluate the effects of ensiling whole plant maize with wet distillers grains with solubles (WDGS) on its preservation and nutritive value. In the first study, WDGS was blended with whole maize plants at 0% (control), 10%, 20%, 30% and 40%, and ensiled for 120 days in bottle silos in a complete randomized design. Fermentation was monitored by taking samples at day 0, 7, 21, 42 and 120. Results showed a steady decrease (P<0.05) in dry matter (DM) concentration with increasing level of WDGS inclusion. Final silage pH was lowest (P<0.05) for the 40% WDGS treatment (pH 3.62) and highest for the 10% WDGS treatment (pH 3.79). There was no effect (P>0.05) of level of WDGS inclusion on initial buffering capacity (day 0), as well as for day 42 and 120 samples. Lactic acid was higher (P<0.05) at day 120 for the control treatment than those blended with WDGS, which did not differ significantly. The concentration of acetic acid was higher value (P<0.05) for silage treatments blended with WDGS than the control, with that of 40% WDGS level of inclusion recording the highest (P<0.05). The control and 40% WDGS treatments had lower (P<0.05) ammonia nitrogen concentration (g/kg N) than the other treatments at day 120. The second trial involved monitoring ruminal fermentation characteristics of cannulated sheep fed three experimental diets. Formulated diets contained maize silage mixed with 24% dried distillers grains with solubles (MS DDGS treatment ), maize silage mixed with 19.5% sunflower oilcake meal (MS SOM treatment), and silage blend of 91% of whole maize plant/9% WDGS (WDGSMS treatment), all on a DM basis, to obtain iso-nutrient diets. The mean value for rumen pH, NH3N and total VFA concentrations among diets did not differ (P>0.05) among treatments. The individual VFA were similar with only butyric acid being lower (P<0.05) in sheep fed WDGSMS. There were no differences in the acetic:propionic acid ratio among treatments. The third trial involved the determination of DM degradability of the three formulated experimental diets using the nylon bag technique. Effective degradability was measured at two outflow rates, 2% and 5%. The diets did not differ (P>0.05) for washing losses (avalue), slowly degradable DM fraction (b-value) and rate of degradation of DM (c-value). Treatment MS SOM recorded the highest effective degradability with MS DDGS having the lowest at 2% outflow rate. The effective degradability value at 5% outflow rate for WDGSMS was not significantly different from that of MS SOM and MS DDGS, which differed significantly. In the final study, experimental diets were fed to three groups of eight lambs in a growth performance trial. The groups offered MS DDGS and MS SOM had superior (P<0.05) final mass (g/head), average daily intake (gDM/kg0.75) and average daily gain (g/head/day), than those offered WDGSMS. The feed conversion ratio did not differ (P>0.05) among all treatments. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted

No description available.

Master of Science / Department of Agronomy / Scott A. Staggenborg / With the increase in bio-energy production there is also an increase in by-products. Without proper disposal, these by-products might cause future economic and/or ecological problems. Land application has potential as a disposal and/or nutrient cycling method if these by-products have nutritive value for agricultural crops. The purpose of the study was to compare the use of two by-products of bio-energy production, dry distillers grains (ethanol) and charcoal(pyrolysis), as fertilizer with urea in corn (Zea mays L.). The experiment consisted of four location-years in Kansas. Treatments were dry distiller’s grains (DDG) no-till and tilled for four location-years and char no-till and tilled for three location-years. No-till urea was used as a baseline for comparison at all location-years. The Nitrogen rates ranged from 45 to 180 kg N ha-1. All source material was spring applied before tillage and planting. The corn yields for DDGs and urea were the almost the same across tillage treatments and locations. For DDG no-till, DDG tilled, and urea, the rates at which to achieve the same yields were 97, 111, 78 kg N ha-1, respectively. Corn yields for char at all rates and tillage treatments were the same as no fertilizer. The char, because of immobilization or lack of decomposition, did not contribute to the nitrogen needs of the corn. Neither material showed any inhibitory or otherwise negative effects on the corn in terms of grain yield compared with the control. But both DDGs and char had to have large amounts of material applied to achieve the same amount of nitrogen as urea. Land application of DDGs and char has potential merit for disposal/nitrogen cycling with DDGs being preferred for its nitrogen contribution.