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Item Corn versus barley in beef cattle finishing diets: effect on steer performance, feeding behavior, and ruminal environment(Montana State University - Bozeman, College of Agriculture, 2021) DelCurto-Wyffels, Hannah Margaret; Chairperson, Graduate Committee: Megan Van Emon; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Corn versus barley in finishing diets: effect on steer performance and feeding behavior' in the journal 'Animals' which is contained within this dissertation.; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'The influence of environmental conditions on intake behavior and activity by feedlot steers fed corn or barley-based diets' in the journal 'Animals' which is contained within this dissertation.; Hannah M. DelCurto-Wyffels, Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Diurnal ruminal pH and temperature patterns of steers fed corn or barley-based finishing diets' in the journal 'Animals' which is contained within this dissertation.While corn is the most common feed ingredient in the United States, barley, which is more suitable for the growing and climatic conditions at northern latitudes, can be a common feed alternative to corn. The different digestive utilization of unique feedstuffs coupled with extreme environmental conditions can pose challenges to efficiently feeding cattle in different climates. Thus, to further our understanding of the use of barley in feedlot diets at northern latitudes this study evaluated the effects of barley and corn finishing rations on feedlot performance, feeding behavior, and ruminal environment. For two consecutive years, Angus-based yearling steer calves were fed in a feedlot trial (427.3 + or - 3.7 kg; n = 48 in year 1, and 406.8 + or - 3.4 kg; n = 47 in year 2). Steers were randomly assigned to one of two primary basal grain dietary treatments: 1) Number 2 feed corn or 2) Hockett barley. Steers were fed in a GrowSafe system to measure individual animal intake and behavior throughout the duration of the study. Twelve steers per treatment group for each year of the study were also fitted with a HOBO pendent G accelerometer to measure activity and a SmaXtec ruminal bolus for continuous rumen monitoring of temperature and pH. Limited differences were observed in regard to performance and eating behavior of steers fed corn or barley-based diets. The steer's diet interacted with short term environmental changes to influence animal feeding behavior, but diet had limited impact on cattle lying activity. Continuous ruminal monitoring revealed average daily ruminal pH and temperature were not impacted by diet; however, diet did affect daily variation in ruminal pH and temperature. Intake patterns were also different between corn and barley-fed steers in which corn-fed steers consumed more feed the first 6 hours directly after feeding while barley-fed steers consumed more feed later in the day. Presumably, these intake patterns could be influenced by differences in diurnal patterns of ruminal pH between corn and barley. Depending on cost and production year, both barley and corn can be high quality feedstuffs to use in beef cattle finishing rations.Item Price relationships in the U.S. nitrogen fertilizer industry(Montana State University - Bozeman, College of Agriculture, 2018) Gumbley, Thomas J.; Chairperson, Graduate Committee: Anton BekkermanThis study estimates the price dynamics in the U.S. nitrogen fertilizer industry, measures information flow efficiency in spatially separated fertilizer markets, and measures to what extent structural changes in corn and natural gas markets may have altered these price dynamics and information flow relationships. A vector error correction model is used to measure the short-run and long-run relationships between nitrogen fertilizer markets, natural gas markets, and corn markets. The results show that price information flows from the central market of New Orleans to inland regional markets. The efficiency of this information flow increased in the period after the Renewable Fuel Standards increased the demand for corn.Item Corn production as affected by rates of nitrogen and phosphorus fertilizer at three locations in Montana(Montana State University - Bozeman, College of Agriculture, 1967) Erb, Donald MacerItem The effect of three drying temperatures on the germination of corn harvested at three stages of maturity(Montana State University - Bozeman, College of Agriculture, 1971) Wobil, JosiahItem A biomass-fired grain dryer : system design, construction and performance(Montana State University - Bozeman, College of Agriculture, 1984) Little, Mark AnthonyItem Monensin effects on digestion of corn or barley high concentrate diets(Montana State University - Bozeman, College of Agriculture, 1995) Surber, Lisa Marie McKinleyItem Relationships of factors affecting the growth and composition of corn forage on irrigated soils in Montana(Montana State University - Bozeman, College of Agriculture, 1964) Watkins, Richard EarlItem Transitory leaf starch is an important determinant of plant yield(Montana State University - Bozeman, College of Agriculture, 2011) Schlosser, Alanna Jane; Chairperson, Graduate Committee: Michael J. Giroux.Efficient allocation of photoassimilates from source to sink tissues is important for optimal plant growth and yield as relative source and sink strength drives growth potential of plant organs. A common method aimed at improving plant yield has been to modify enzymes important to storage compound biosynthesis in sink tissues such as seeds. As the rate limiting step in starch biosynthesis, ADP-glucose pyrophosphorylase (AGPase) has received much attention in this regard. Previously, overexpression of AGPase in seeds resulted in an enhanced yield phenotype in which both plant yield and biomass were increased. However, yield advantages were only observed under nonlimiting environmental resources. The objective of these studies was to 1) determine the importance of native leaf starch levels to the productivity and growth of maize and 2) target source strength by overexpressing AGPase in rice leaves. To determine the importance of native leaf starch levels in maize, field trials of BC 4F 2:3 plants segregating for the presence or absence of the agps-m1 mutation and leaf starch were conducted in Citra, Florida. The results clearly demonstrate the importance of normal leaf starch levels to maize productivity. The starchless agps-m1 plants were 6 to 13 cm shorter, flowered 2 to 3 days later, and had 30 percent lower seed yield than their wild type sisterlines. The impact of increased AGPase in rice leaves was then tested by overexpressing AGPase in rice leaves. Two expression constructs were used to transform rice cultivar Nipponbare, each containing a modified form of the maize endosperm AGPase large subunit sequence, Sh2r6hs, as well as the small subunit sequence, Bt2. Expression of the transgenes was under control of either the rice leaf AGPase small subunit promoter, Ags1, or native rice RuBisCO small subunit promoter, RBC. Expression of the transgenes under the RBC promoter is associated with significantly increased plant biomass. Our results indicate that it is possible to increase plant yield without increasing the rate of photosynthesis. Further, it indicates the possibility of manipulating plant yield through increasing AGPase activity in leaf tissue.Item Satelite production forecasts : vauled with simulated futures and options trading(Montana State University - Bozeman, College of Agriculture, 2005) Martin, Lucanus Earl; Chairperson, Graduate Committee: Joe Atwood.Both the USDA and private firms are allocating substantial capital towards providing accurate and timely crop production forecasts. Production forecasts based on satellite imagery have been suggested as a means of making forecasts earlier, more frequent, and cheaper. This thesis attempts to determine if satellite data increases information with respect to crop condition and final production. If so, does the additional information have value and can it be used to make profitable trades in the futures market? These questions are answered using NDVI data for Iowa and Illinois. Jackknifed out-of-sample crop production estimates are calculated for both corn and soybeans for the individual states. A variety of models were used, each including different bi-weekly periods. USDA crop condition scores are also tested in some of the models. A model based on the current stocks-to-use ratio for each commodity is used to predict the market's expected production level. When the satellite forecast differed from the market's expectation a trade was made in the futures markets. Both futures and option strategies were tested. Results suggest that satellite based production forecasts may result in profitable soybean trades, particularly when downside risk can be reduced by trading options. Further work should focus on refining the satellite images used in the model and exploring more complex option trading strategies.Item Evolution of the molecular mechanisms of pheromone reception in European and Asian corn borer moths(Montana State University - Bozeman, College of Agriculture, 2010) Allen, Jean Elaine; Chairperson, Graduate Committee: Kevin Wanner.; Kevin W. Wanner, Andrew S. Nichols, Peggy L. Bunger, Stephen F. Garczynski, Charles E. Linn Jr., Hugh M. Robertson and Charles W. Luetje were co-authors of the article, 'Sex pheromone receptor specificity in the European corn borer moth, Ostrinia nubilalis' in the journal 'PLoS ONE' which is contained within this thesis.; Kevin W. Wanner was a co-author of the article, 'Asian corn borer pheromone binding protein 3, a candidate for evolving specificity to the 12-tetradecenyl acetate sex pheromone' in the journal 'Insect biochemistry and molecular biology' which is contained within this thesis.The insect order Lepidoptera includes more than 180,000 species and some of the most well known pests of food and fiber crops. Ninety-eight percent of lepidopteran species belong to a taxonomic group called the Ditrysia. Modern Ditrysia use long distance sex pheromones to facilitate mating. The European corn borer, Ostrinia nubilalis (ECB) is a well known pest of agricultural crops throughout North America and Western Europe. The European corn borer species exists as two different pheromone races. Females of the species produce, and males are attracted to different blends of the isomers (Z)-11-tetradecenyl acetate and (E)-11-tetradecenyl acetate. The closely related Asian corn borer (O. furnacalis, ACB) has evolved to use a pheromone blend that is unique among all Lepidoptera, (Z)- and (E)-12-tetradecenyl acetate. O. nubilalis and O.furnacalis species can be used as models to study pheromone evolution. Pheromones are detected at the periphery of the olfactory system by olfactory sensilla located on the antennae. Proteins involved in pheromone detection at the periphery include: odorant receptors, pheromone binding proteins, and sensory neuron membrane proteins. In this study, the coding sequences of seven odorant receptors, five pheromone binding proteins, and two sensory neuron membrane proteins were cloned from Asian and European (E and Z race) corn borer antennae. Five odorant receptors and two pheromone binding proteins were expressed at high levels in male corn borer antennae based on quantitative real-time PCR assays. Several odorant receptors were heterologously expressed in Xenopus laevis oocytes, and odorant receptor 6 was found to respond specifically to (Z)-11-tetradecenyl acetate in electrophysiological studies. The coding sequences of all fourteen genes were analyzed by computational and statistical methods to identify candidate genes that may play a role in the detection of the ACB pheromone blend. Odorant receptor 3 and pheromone binding protein 3 may have evolved specificity to 12-tetradecenyl acetates. Future studies will clarify the role of these proteins in the evolution of pheromone detection at the molecular level. An improved understanding of the evolution of pheromone detection may lead to new pheromone based controls for these economically damaging species.