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Agricultural Experiment Station

Current Projects

These projects are also accessible through the CRIS web site of the U.S. Department of Agriculture.

Davis Dairy Plant Dryer

SD00H644-18. MANUFACTURE OF DAIRY BASED INGREDIENTS. (October 2017 - September 2022) Dr. Lloyd Metzger

NON-TECHNICAL SUMMARY: In the U. S., milk production has steadily climbed from 115 billion lbs in 1975 to over 208 billion lbs today. This increase in milk production has been largely driven by a steady increase in milk production per cow. On average, since 1960 milk production has increased by 273 lbs per cow per year. It is interesting to note that in the last twenty years cow numbers have remained fairly constant at approximately 9.1 million. If cow numbers continue to remain constant we can expect to have an additional 2.5 billion lbs of milk (9.1 million cows x 273 lbs milk per cow) produced each year. The U.S. population grows at a rate of approximately 3 million per year. This increase in the U.S. population as well as increases in per capita consumption will partially compensate for the expected increases in milk production. However, excess milk will be available if the US dairy industry continues to maintain cow numbers. An additional potential market for the excess U.S milk supply is dairy based ingredients targeted for export markets. In fact in the last 15 years the amount of dairy products exported has more than quadrupled. This represents a drastic change from the past when the US dairy industry only exported products as a result of government export subsidies.In order to continue the trend of a rapidly expanding export market, the U.S. dairy industry needs to identify components of milk that are the most valuable and determine how these components can be economically isolated and converted intoshelf stable products that can be widely distributed and utilized as ingredients in a variety of products. The major components of milk include water (88%), lactose (4.8%), fat (3.5%), protein (3.2%) and minerals (0.70%). Of these components, protein is considered to be one of the most valuable. Currently, world demand for dairy protein exceeds the world supplyand the U.S. will have an opportunity to expand its milk production if economical systems to manufacture and fractionationmilk protein are available. In addition to protein there are also opportunities to produce dairy based ingredients that are rich in lactose, fat and minerals. The objective of this project it to develop and improve manufacturing processes to produce dairy based ingredients that have an extended shelf-life and can be utilized in domestic and international markets.The successful development or new dairy based ingredient manufacturing processes, as well as improvements in the efficiency of current dairy ingredient manufacturing processes, will allow for the continued growth of the US dairy export market. The economic impact of the US dairy export market is significant and is currently valued at 4.9 billion.

OBJECTIVES: Project goals and objectivesThe overall goal of the project is to develop and improve manufacturing processes to produce dairy based ingredients that have an extended shelf-life and can be utilized in domestic and international markets.Objective 1: Model the drying characteristics of dairy based ingredientsto maximize the efficiency of the drying process and accelerate the development of new dairy based ingredients.Objective 2: Develop a lab scale crystallization system and analysis protocols that will be utilized to evaluate modified manufacturing processes that improve the efficiency of lactose and permeate manufacture.Objective 3: Develop and evaluate membrane based manufacturing processes that can be used to isolate or concentrate components in various dairy products including milk, whey, permeate and delactosed permeate.

SD00H648-18. CARBOHYDRATE BASED CARRIERS OF BIOACTIVE COMPOUNDS. (October 2017 - September 2022) Dr. Srinivas Janaswamy

NON-TECHNICAL SUMMARY: Bioactive compounds (BCs) provide health benefits, especially for the prevention and treatment of chronic diseases such as diabetes, obesity, cardiovascular disease and cancer. A study on pigmented potatoes suggests that the glycemic index is significantly related to the amount of polyphenol present in the potatoes. Similarly, 24 years of research on US men and women clearly highlights the benefits of consuming foods rich in anthocyanins and dietary flavonoids to maintain a healthy weight. Furthermore, a 9-month curcumin intervention in apre-diabetic population significantly lowered the number of pre-diabetic individuals; this suggests the beneficial role of curcumin for preventing Type 2 diabetes mellitus (T2DM). Thus, supplementation and fortification of foods with BCs are useful for maintaining good health. This concept is further supported by the recent consumer awareness and demand for healthy foods. However, incorporation of BCs in foods is a major technological challenge due to low water solubility, and instability during processing and storage. Thus, delivery of BCS through food systems is a challenge. Carriers that are compatible with the human digestive systemwill be a solution to effectively incorporate?BCs in food and in this regard carbohydrates standout as favorable choice. Carbohydrates composed of starches and polysaccharides are staple foods and form basic energy source for humans. Carbohydrates exhibit a wide variety of unique chemical structures and physiological functions. They are capable of significantly altering texture, gelation and viscosity of aqueous based solutions, and a wide range of products can be developed using carbohydrates as functional ingredients. More importantly, they form the bulk of many foods consumed by humans and play a central role in human health. They are inexpensive; hence, their utilization for delivering BCs will not only be significant in developing health promoting and disease preventing food supplements, functional foods, and medicinal foods, but they also provide the opportunityto exploit highly used and low-cost biomaterials as value-added products. The overall objective of this project is the design and development of novel carbohydrate-based delivery systems for BCs in food, pharmaceutical and medicinal applications. The proposed research is based on the PI's hypothesis that BCs can be effectively embedded and protected in the ordered networks of carbohydrates. The hypothesis is strongly supported by the following five observations. (1) Though polysaccharides are mostly amorphous in nature, structural ordering can be achieved by preparing crystalline structures and well orienting fibers under suitable experimental conditions. (2) In the crystalline state, polysaccharides adopt stable helical structures with well-orchestrated networks stabilized by intra- and inter-helical hydrogen bonds mediated via ordered water molecules and cations. (3) In the polysaccharide network, especially in anionic samples, there are 15-25 Å wide voids often filled with water molecules, and such water pockets are amenable for embedding BCs. (4) In the case of starches, there are water channels of 16Å diameter in root starches such as potato starch that are capable of embedding BCs. (5) Starch granules such as corn starch could be treated with enzymes to create micrometer scale pores amenable for encapsulating BCs. This project will evaluate the optimal conditions for entrapment and release of BCs in carbohydrate networks (oriented fibers, starches and porous starch granules) and establish the stability and bioavailability of entrapped BCs. The loaded amounts of BCs will be determined using High Pressure Liquid Chromatography (HPLC) and UV-Vis spectroscopy. The complexes will be characterized through a series of techniques such as X-ray fiber diffraction, X-ray powder diffraction, Fourier-Transform Infrared spectroscopy, Scanning Electron Microscopy and Differential Scanning Calorimetry. The protection provided by the complexes for the BCs against digestive pH, heat, light and moisture will be established. The release rates will be determined in aqueous, simulated gastrointestinal conditions and rat studies. Overall, the outcome offers an elegant opportunity to design and develop value-added food products based on bioactive compounds that promote good health and prevent diseases.

OBJECTIVES: (1)preserve the structural form of a BC until the time of delivery, and (2) effectively deliver the preserved form to the physiological target. The following two objectives are carefully designed to provide a comprehensive evaluation of the proposed research strategy.1. Explore the effectiveness of various carbohydrate-based carriers in encapsulating BCs2. Assess the stability and bioavailability of encapsulated BCs.


NON-TECHNICAL SUMMARY: Enhancing the microbial quality and safety of milk and dairy products is an ongoing challenge. As a result of ever changing processing technologies and emerging issues related to spoilage and disease causing microorganisms, effective and efficient control of bacteria in dairy processes is critical if U.S. dairy products are to compete in the multi-billion dollar global export market. Some sporeformers and endospores resist thermal treatments and are primarily responsible for spoilage of milk and dairy products. It is thus imperative to find process interventions to control their proliferation. Our previous research in this area demonstrated hydrodynamic cavitation as a process that can be combined with pasteurization to inactivate thermoduric sporeformers and their spores. Further research in this area can help us scale-up this process, and at the same time identify processing conditions that will influence the sporulation and spore germination behavior of common dairy sporeformers. This will help the dairy industry reduce the adverse effects of sporeformers and manufacture products that can easily compete in global markets. Another important aspect related to dairy products is safety. Several incidences of food poisoning have affected the credibility of dairy products as wholesome for consumers, and resulted in serious economic consequences. Forexample a recent large outbreak involving Listeria monocytogenes in ice cream resulted in major recalls and shut down ice cream manufacturing facilities for several months. The persistence of Listeria;in dairy processing environments, and ability to cross-contaminate ice cream is not clearly understood. We propose to conduct challenge studies in simulated ice cream manufacturing processes to generate response surface models to predict risk more accurately. This will help us design more robust hazard analysis and risk-based preventive controls (HARPC) for preventing food pathogens such as Listeria. The project will be conducted in collaboration with industrial partners to generate risk models directly applicable under field conditions. The information generated will help the dairy industry prevent food borne outbreaks.Improving the nutritional value of dairy ingredients, especially by designing new products and formulations, is the next thrust area identified by US dairy industry. Probiotic applications will play a significant role in this attempt due to increased consumer acceptance and growth in this sector of fermented dairy products. At the same time, value added byproducts such as whey protein isolates and concentrates provide additional avenues for developing health products. We plan to develop an encapsulated probiotic product using whey protein hydrolysates as encapsulants. Such a product will have the recognized health benefits of both whey proteins and active probiotic cultures. This will provide the dairy industry with another novel dairy product in the healthy products portfolio.

OBJECTIVES: Goal 1: To improve microbial quality and shelf life of milk and dairy productsObjective 1.1: To understand sporulation behavior of common sporeformers during milk powder manufacture Objective 1.2: To apply non-thermal technologies, such as cavitation, to control common dairy sporeformersGoal 2. To improve microbial safety of dairy processesObjective 2.1: To control dairy pathogens such as Listeria by risk analysis, through response surface models.Goal 3. To develop novel dairy products containing probiotics.Objective 3.1: To develop a spray-dried health formulation based on whey protein hydrolysate and probiotics encapsulation.


SD00H619-17 VALUE ENHANCEMENT OF HEALTH, NUTRITION AND ECONOMIC TRAITS OF CEREAL GRAINS (December 2016 - November 2021) Dr. Padmanaban Krishnan, Karl Glover, Sunish Sehgal. Melanie Treml, Jill Anderson, Sanjeev Anand, Sergio Martinez-Monteagudo..

NON-TECHNICAL SUMMARY:  Increasing food production to meet the demands of a hungry world requires concerted efforts in the area of research into production agriculture, end use, safety, quality evaluation, economics, sustainability and nutrition. Corn, wheat and Oats remain as important cash crops that provide a significant proportion of nutrients to people in the world.The value of traditional cash crops of agriculture such as corn, wheat, soy and oats are determined by their end-use in the market place. Such value is based on the finished food products as consumed by people i.e. after processing. Farmers and producer are often interested in agronomic traits such as yield, disease resistance ease of growing, susceptibility to the environment and production practices. Newer factors such as sustainability and environmental effects also play a part in the choice of varieties employed in farming. End users may have a separate set of criteria to gauge the economic value of the raw materials used in food processing. Different sets of criteria exist for quality determinations of food crops at various stages in the development toward finished food products. Plant breeders, geneticists need close collaboration with quality traits experts to realize their breeding objectives.Quality target trait goals in breeding programs therefore, may change frequently from year to year depending upon growing conditions, making it necessary to monitor multiple quality traits. Protein content, protein quality, milling yield, gluten strength, constituent food functionality and nutritional composition. Quality evaluation programs for cereal grains are diverse and require quality measurement platforms that yield accurate and useful real time information that can be used in decision-making. Rapid and multi constituent analysis capabilities such as Near Infrared reflectance technology provide this information. Non-destructive whole seed analysis also give plant breeders additional advantages as the seeds are still viable post analysis. It is for these reasons that grain and cereal quality programs seek longitudinal information on crops as quality traits found in any one year does not yield sufficient data in order to make meaningful predictions and projections on food quality. Food quality requires the availability of uniformity, consistency and predictability in the properties of food materials used as ingredients in food production. Tools, instruments and end-use processing capabilities for such raw materials enable data acquisition and allow breeders, processors and consumers the ability to making meaningful observations and projections on food quality.A practical response to this varied need by food producers and food processors is the development and refinement of a Crop Quality Evaluation platform based on scientific methods. This program will provide research information on current and new varieties of oat and wheat varieties, generated through experiments employing advanced grain quality instruments and techniques. Oat and wheat breeders will use this data to make informed-decisions about parental lines used in making genetic breeding. Food processors will use the quality information in using agricultural crops in their finished food products. PD Krishnan's project will generate new information, new tools, new services, new protocols and new products for increased food production and economic enhancement of food crops.

OBJECTIVES: The goals of this project are to enhance the health, food functional, nutritional and economic value of cereal grain crops grown in the state and region. The efforts will be geared toward improved and enhanced food production and increased monetary and health value cash crops such as wheat, oats and corn.To investigate the rheological traits and food functionality traits of South Dakota wheat varieties in new applications (Asian noodle, tortilla, pizza dough, flat breads) with a view to expanded food uses and determination of genetic and environmental causes of wheat constituent and functionality variability.To evaluate the nutritional and dietary fiber composition fiber of oat cultivars used in the US food supply using rapid and non-destructive techniques such as Near Infrared analytical. To investigate the development of high-value wheat fractions (vital gluten, high-selenium bran, high selenium and whole white wheat) that increases the economic and health benefits of South Dakota grown wheat. To provide collaborative assistance in the discipline of Cereal Chemistry and Wheat Quality to the winter and spring wheat breeding programs as well as the Oat Breeding Program at South Dakota State University. To engage with food companies in the investigation of rapid food quality evaluation tools and instruments.To increase the value (wholesomeness, safety and efficacy) of corn and corn fractions through the development of new food ingredients, nutraceuticals, and bioactive food agents.Success in these goals and achievement of the objectives will result in:increased profitability to farmers and producers increased acceptance and use of SD wheat and oat varieties used in food processing Along-term quality assurance of agricultural materials increase dmonetary value of cash crops used in new foodapplications New finished food ingredients and food products with heath benefits and nutritional value Access of information to plant breeders (wheat and oats) leading to development of new genetic lines and varieties.Development of new tools and advanced instruments to investigate bread baking potential New blends of cereal grain fractions with enhanced proteins, dietary fiber and bioactive constituents

Aug 2016 - Aug 2021. Dr. Johan Osorio and Jill Anderson

NON-TECHNICAL SUMMARY: To give birth to a new life is a common event to all mammals, however, there are striking differences across mammalian species on how birthing andthe onset of lactation can affect the dams' health. Extreme examples of this are the physiological and metabolic adaptations that dairy cows undergo due to stresses caused by the onset of lactation.For instance, it has been estimated that in dairy cows thatenergy and protein requirements canincrease up to 5 times from late gestation to lactation (i.e., transition period). Therefore, during the past 3 decades a substantial amount of research has been conducted to understand how these biological adaptations can predispose dairy cows to negative effects in health, and consequently in the lactation performance of transition dairy cows. Additionally, nutritional and management interventions have been investigated with the aim to ameliorate these negative effects.Nutrigenomics is a fruit of the post-genome era, and is a scientific branch of nutrition that studies how molecules contained in the diet can modify the biology ofsingle cells, to the organism as a whole, by turning on or off specific genes (i.e., gene expression). Previous research in transition dairy cows has demonstrated the potential for nutrigenomics effects based on specific dietary components such as amino acids (Osorio et al., 2014a) and trace minerals (Batistel et al., 2016) with positive effects on health and performance. Regardless of these findings, there are still fundamentalunanswered questions: 1) what are the molecular mechanisms through whichby specific nutrientsexertchanges in gene expression2) can accurate prediction of gene expression outcome be made based on nutrient levels in the diet?Although nutrigenomics can have a profound impact on overall health status and performance of dairy cows, there isa need for early detection systems for diseases in the subclinical stage, which will allow for more timely interventionsby dairy producers.The latter can considerably decrease the recovery time from a disease, and result in lowering the treatment cost while improving milk production. Although devices that measurehealth indicators have been used since the 1980's in dairy cows with their incremental adoption, there is still a lot of work to be done in sensor system development.For instance, recently a literature review reported that automated lameness detection systems were only able to detect severe lameness, which farmers can easily detect by direct observation. Therefore, the calibration of sensor system data needs to be done during the early stages of subclinical diseases. This task can only be accomplished by an adequate understanding ofthe physiological adaptations that occur during early stages of subclinical diseases. Biomarkers in blood and specific tissues such as liver had generated fundamental knowledge in the biology of diseases in terms of inflammation, oxidative stress, and overall animals' welfare. During the subclinical stage of a disease, biomarkers can be sensitive enough to respond toalterations in the normal physiology of dairy cows. However, the use of biomarkers in blood and tissues can be limited or unrealistic for real-life applications in dairy farms. In contrast, sensor systems devices have been developedto be ready for a dairy farm setting. Therefore, combining automated detection systems data with biomarkers have a great potential to improve the early detection of subclinical diseases in dairy cows.Improving health and performance of transition dairy cows is a complex task that requires multiple approaches. The proposed research program will help producersfine-tune the metabolism of transition dairy cows based on nutrigenomic data. The fine-tuning of automated detection systems will help producers identify cows at risk to developdiseases during subclinical stages. These capabilities will serve as important tools in modern dairy farms with profound financial impact to the dairy industry.

OBJECTIVES: Overall goal: Improve the health and consequently the postpartal performance of transition dairy cows through either nutrigenomic approaches or sensor systems.Validate the activation of peroxisome proliferator-activated receptor (PPAR) via specific fatty acids and determine new transcription factors (TF) that have greater direct activation by fatty acids through advanced molecular techniques such as gene reporter technology (GRT).Determine novel transcription factors (TF) that respond directly to other dietary nutrients or compounds such as amino acids, trace minerals, vitamins, etc.Validate and confirm the in vitro novel transcription factors (TF) uncovered in Objectives 1 and 2 at a whole animal level through in vivo experiments in lactating dairy cows.Improve automated sensor systems for early detection of postpartal diseases or disorders at the subclinical stage by combining sensor data with biomarkers of health status.

May 2016 - Apr 2021. Drs. Sergio Martinez-Monteagudo and Sanjeev Anand.

NON-TECHNICAL SUMMARY: Dairy products have been a key component of a healthy diet and a source of many nutrients. Dairy manufacturing industry employs advanced processing technologies to deliver a variety of products and ingredients. New trends in consumers' life style have redefined the desired attributes of processed foods they would like to have. Assurance of microbial safety is no longer sufficient; instead modern American consumers are looking for product formulated with healthy ingredients, free of additives, fresh-like characteristics, and natural flavor. However, the design and development of ingredients and products formulated with such characteristics and without compromising the safety of the product is a major challenge from a technological point of view. Most of the desired compounds differ from the product matrix in terms of solubility, melting point, and chemical compatibility. Thus, such compounds must first be converted into a stable phase using additives and high input of mechanical energy. Searching for solutions to address the continuous market changes, engineers and scientists have been evaluating various technological approaches that involve the use of advanced thermal technologies (microwave, radiofrequency and Ohmic heating) and non-thermal technologies (high pressure processing, pulsed electric fields, ultrasound, supercritical fluid technology) to potentially meet rising consumer expectations. Intelligent combinations of different emerging technologies have showed some promises for improving the manufacturing protocols, and enhancing overall quality and nutritional content. Successful applications and niche of opportunities for emerging technologies have been highlighted in the literature. A step forward towards the implementation of emerging technologies in dairy manufacturing is to establish relationships between operating variables and product properties. Thus, desired product properties can be controlled and optimized through operating parameters. The challenge is that the effects of different emerging technologies on milk and its constituents are largely unknown and specific key components is still incomplete. Such knowledge is essential for development, validation and commercial introduction of novel applications for dairy manufacturing. This research program will focus on systematic studies aimed to understand how emerging technologies and their associated operating parameters impact the properties of milk and its constituents, all with an eye towards industrial applications.

OBJECTIVES: The overall objective of this research program is to generate scientific understanding of the behavior of dairy systems and their individual components during manufacturing. Specific objectives: To characterize engineering parameters of high pressure homogenization. To investigate the efficacy of combined pressure-temperature on safety and selected quality parameters of dairy beverages. To evaluate the role of pressure on emulsion stability within a wide range of processing conditions.


NON-TECHNICAL SUMMARY: The US is home to 51,500 dairy farms and 9 million dairy cows. The profitability and sustainability of dairy farming depends on efficient management practices that result in maximizing milk production at a minimum monetary and environmental cost. Therefore, the focus of this project is to provide for collaborative research leading to dairy management strategies and systems to facilitate sustainable and profitable decisions by managers of milking cow and heifer enterprises. Dairy farming is a highly integrated decision intensive system. It must rely on a systems approach to define options to maintain a profitable business, accountable to consumers for environmental impacts, product quality and animal well-being. Profitable decisions cannot be made without useful support systems.

OBJECTIVES: Optimize calf and heifer performance through increased understanding of feeding strategies, management systems, well-being, productivity and environmental impact for productivity and profitability. Improve dairy cow management decisions through nutrient utilization, well-being and profitability. Analyze whole farm system components and integrate information into decision-support tools to improve efficiency, enhance profitability, and environmental sustainability.


NON-TECHNICAL SUMMARY: There is still much to understand on how nutrition affects animal growth and development. It has been demonstrated that how a young animal is fed during critical developmental periods can impact performance at maturity. Although, there is only a small amount of information available related specifically to dairy heifers. There is a growing body of information focused on young calves, but limited research exists on metabolism of dairy heifers around puberty, with the majority of conducted research associated with mammary development. Studies on beef animals and other species have demonstrated that metabolic profiles (blood hormone and metabolite concentrations) can impact key developmental processes such puberty onset. In dairy heifers it has been demonstrated that body weight rate of gain can impacts puberty onset and mammary development. There is limited research however, on how different rates of gain impact metabolic profiles. One question that remains unanswered is how different dietary energy sources rather than amounts impact metabolic profiles. This leads to a second question: do changes in metabolic profiles impact developmental processes such as puberty and growth? Previous research (Anderson, 2012) found that feeding dairy heifers fat from distillers grains in replacement of starch from corn grain could alter plasma lipid profile and decrease age at puberty while maintaining similar growth performance. It is important to further explore the effects of dietary fat on puberty of growing dairy heifers. The first proposed study will examine using fat and non-forage fiber from distillers grains as energy sources substituting forage fiber. A second, shorter study will determine if forage particle size affects total tract protein and fiber digestibility in diets with a large percentage of the concentrate mix supplied by distillers grains. Additional future studies will be developed building on the results from these first two experiments. The overall goal of this research is to gain an understanding of how dietary nutrients and energy sources affect metabolism in growing dairy heifers. By understanding this relationship, recommendations can be made on feeding new feedstuffs and alternative feeding strategies can be better developed. This research will help dairy producers understand more completely their feeding options for growing replacement stock and better adapt to changing feed markets and complex environmental issues. By understanding effects of different energy sources on metabolism, lower cost diets that maintain or enhance growth performance while decreasing waste and nutrient excretion can be developed. By gaining further insight in heifer metabolism we may be able to change the timing of puberty, decrease the breeding age (and time it takes the heifer to begin lactation) with limited long-term negative consequences. This research could be very beneficial to producers as it could reduce overall rearing costs and allow for faster return on investment.

OBJECTIVES: Overall: Determine how different dietary energy sources impact calf and heifer growth, nutrient digestion, metabolism, and reproductive development. Determine if energy and protein from distillers grains can replace energy and protein from forage sources in growing dairy heifer rations in precision feeding scenarios. Determine how particle size of the ration forage with slowly degradable concentrate sources influences total tract digestion of feedstuffs in precision-fed rations for dairy heifers. Determine how much supplemental fat can be fed in replacement of starch from corn in moderate forage (> 50%) heifer diets. Long term goal. Determine if manipulation of the energy sources in diets of dairy heifers can decrease age at puberty and breeding, and therefore shorten the time it takes to initiate lactation without negatively impacting milk production of primiparous cows.

NC1040. METABOLIC RELATIONSHIPS IN SUPPLY OF NUTRIENTS FOR LACTATING COWS (Oct 2007 - Sept 2012) Drs. David Casper, David Schingoethe and Kenneth Kalscheur

NON-TECHNICAL SUMMARY: Feeding for optimal nutrient intake requires not only the provision of the necessary nutrients for milk production but also consideration to the effects of diet on mammary capacity and on appetite, health, and metabolic regulation of the cow. Because feed costs account for half of all costs on a dairy farm, nutrition also significantly impacts farm expenses. The long-term goal is to improve the efficiency of milk production, cow health and longevity, and thus promote environmental and economic sustainability in the US dairy industry. The approach to achieve this goal is to systematically identify those biological and nutritional management processes that will provide the greatest improvements in milk production and sustainability of dairy systems.

OBJECTIVES: 1: To quantify properties of feeds that determine the availability and utilization of nutrients critical to milk production. Based on cost projections, milk fat depression without a loss in milk volume can decrease profitability per cow by one-third. It would also help dairy farmers use greater amounts of byproducts from the bioenergy sector (such as corn distillers grains) more effectively and with less risk of milk fat depression. The purpose of this project is to quantify changes in microbial and milk fatty acids caused by dietary changes. Relationships with applied dietary changes will be important evaluation tools, while experiments with specific substrates will allow us to add a mechanistic interpretation that should improve the overall usefulness of the milk fatty acid information. Our end goal is to both evaluate and improve the utility of milk fatty acid analysis in interpreting results from experimental feeding trials and to introduce their use as a new troubleshooting tool for field dairy nutritionists working for commercial herds. Objective 2: To quantify metabolic and molecular interactions that alter synthesis of milk components. Researchers at several stations will, in several experiments, determine specific interactions among nutrients, hormones and physiological state that impact cow health and productivity. Collaborative (IA, IN, SD, MI, WA) work will examine the effects of prepartal glucagon and glycerol on fatty liver, ketosis, postpartal health, and milk production. Liver will be assayed for expression of metabolic enzymes that control nutrient use. Researchers at SD will conduct experiments on the effect of omega-3 and -6 fatty acid containing feedstuffs on production response parameters in lactating dairy cows. Particular emphasis will be placed upon the influence of these fatty acids on milk composition. Transport of fatty acids in the blood, as well as partitioning of fatty acids to milk or body adipose tissues, will be examined. The effects of these dietary fatty acids on hepatic metabolism, gluconeogenesis, and endocrine regulation of hepatic metabolism in periparturient dairy cows will also be measured.


NON-TECHNICAL SUMMARY: Dairy farming is a decision-intensive enterprise which relies on a holistic systems approach in defining options to maintain a profitable system that is accountable to consumers for animal well-being, environmental impacts, and product quality. The purpose of this project is to develop decision support systems that address nutrition, management, environmental impacts, and economics of 1) calves and heifers and 2) lactating and dry cows.

OBJECTIVES: To evaluate and develop sustainable management systems for dairy herds that address critical quality and variance control factors with implications to economic efficiencies and environmental impacts. Sub-objectives: A. To analyze management and nutrition strategies for replacement heifers as they pertain to production and profitability. B. To optimize lactating and dry cow decision-making as it relates to animal health, nutrient utilization, milk production, reproduction, and profitability.

SD00H220-07. USE OF BIOFUEL COPRODUCTS TO IMPROVE NUTRIENT UTILIZATION IN DAIRY CATTLE (Oct 2007 - Sept 2012) Drs. Kenneth Kalscheur,  Arnold Hippen, David Schingoethe, and Alvaro Garcia

NON-TECHNICAL SUMMARY: The biofuel industry is expanding rapidly resulting in an increase in co-products that can be used by the livestock industry. These co-products are dietary sources of nitrogen and phosphorus that need to be efficiently converted to milk and meat and limit losses in manure. This projects examines nutrient utilization of dairy cattle fed diets using biofuel co-products to reduce losses to the environment.

OBJECTIVES: The overall goal of the proposed research is to improve nutrient utilization of dairy cattle diets using biofuel co-products. By improving nutrient utilization, nutrient excretion to the environment will be reduced and the efficiency to produce milk will be improved. The overall goal will be addressed through the following objectives: 1) Determine optimal concentrations of dietary protein fractions such as rumen-degradable protein, rumen-undegradable protein, and amino acids on N excretion, ammonia loss, efficiency of N utilization and animal performance when fed biofuel co-products; 2) Determine optimal concentrations of dietary P provided by fuel co-products and its effect on ruminal P metabolism and P excretion in dairy cattle; 3) Determine the effect of altering dietary carbohydrate, fat, and protein on rumen fermentation, microbial protein synthesis, and overall nutrient utilization when new biofuel coproducts are included in dairy cattle diets.