NC2042: Management Systems to Improve the Economic and Environmental Sustainability of Dairy Enterprises (Rev. NC-1119)
(Multistate Research Project)
NC2042: Management Systems to Improve the Economic and Environmental Sustainability of Dairy Enterprises (Rev. NC-1119)
Duration: 10/01/2013 to 09/30/2018
Statement of Issues and Justification
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 NC-1042 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.
Objective 1. Optimize calf and heifer performance through increased understanding of feeding strategies, management systems, well-being, productivity and environmental impact for productivity and profitability.
While practices of managing lactating dairy cattle occupy the greatest share of time, effort, and costs associated with dairy farming, the total costs of raising dairy heifers are the second largest contributor to the annual operating expenses of most dairy farms at ~20% of total expenses. This large contribution toward operating expenses would indicate that an opportunity exists to reduce whole farm expenses by reducing the expenditures on raising dairy heifers through improving nutritional management practices.
Dairy heifers comprise a significant and increasing portion of the U.S. dairy industry and have potentially significant environmental and economic impacts. The main goal of this objective is the enhancement of feed efficiency to reduce nutrient excretion and improve the environmental and economic sustainability of dairy calf and heifer enterprises through an increased understanding of the effects of feed management on their performance.
To meet the overall goals, this objective includes: 1.) Assessment of nutrient management, excretion, and retention in calves and heifers to determine measures of increased efficiency for either conventional or grazing animals; and 2.) Evaluation of feed ingredients and feed management strategies, such as limit-feeding, on calf and heifer growth and nutrient excretion and subsequent effects on lactation performance.
Dairy heifers have been traditionally fed diets where the great majority of the consumed nutrients derive from forages fed for ad libitum consumption where the fiber portion of the diet limits voluntary dry matter intake. Diets for heifers that contain less forage may be a logical and cost effective nutritional management practice. Previous studies utilizing limit-fed, lower forage diets for growing dairy heifers have shown that feed costs have declined by up to 16%, feed efficiency was improved from 9 to 30 % and manure output may be reduced by up to 40% compared to a high forage control diet. Additionally, heifer growth is unaffected and first lactation milk and milk component production are equal to heifers fed traditional, higher forage diets.
Reductions in the excretion of N and increases in the efficiency of N utilization have been observed when low forage diets are fed at energy intakes equal to high forage diets. Reducing the ruminal degradability of dietary protein has been shown to improve daily gain or growth efficiency in some studies. Research into the implementation of nutrient synchrony (N and carbohydrate) strategies to improve the efficiency of the N utilization in the growing dairy heifers is very sparse.
Varying the inclusion rates and types of feedstuffs in heifer diets are feed management strategies commonly evaluated to determine the best recommendations for improving feed efficiency and growth rates of dairy heifers. The increasing availability of alternative corn hybrids with enhanced nutrient values make feeding decisions more complicated.
Depending on the region of the US, high quality pasture may only be available for a few months out of the year and pasture alone often cannot meet the nutrient requirements for growth. Energy may have been a limiting factor in growth of dairy heifers grazed compared to those fed conventional diets. Little data are available evaluating supplementation of grazing heifers and comparing types of grazing systems to conventional feeding systems.
Increased understanding of the roles of feed management on feed efficiency and sustainability will provide information and analytical tools about management strategies that will increase sustainability and profitability of heifer operations.
Objective 2. Improve dairy cow management decisions through nutrient utilization, well-being and profitability.
Dairy management research is needed in the areas of well-being, nutrient utilization and profitability.
Dairy cattle well-being is directly related to farm profitability through reduced incidences of disease and disorder. Well-being is related to stocking density, grouping strategies, and milking procedures. The development and acceptance of robotic milkers need to be evaluated to study the reduction in stress.
Nutrient utilization can be enhanced through a more thorough understanding of fiber requirements potentially resulting in less cost to the dairy producer, and through the utilization of oilseeds which may have health and reproductive benefits to the cow. With the development of corn silage hybrids, understanding how to feed them is necessary to take advantage of these newly developed forages. These ideas could result in reduced cost to the producer through purchased grains, but also through improved reproductive efficiency and reduced purchased feed costs.
Agro-industrial co-products and alternative protein sources are major providers of nutrients for our nations dairy herd, continued understanding of how these feedstuffs should be fed to dairy cattle and their resulting impacts on performance needs to be evaluated.
Objective 3. Analyze whole farm system components and integrate information into decision-support tools to improve efficiency, enhance profitability, and environmental sustainability.
Integrated whole dairy farm systems evaluations are essential to capture component interactions conducive to more sustainable production systems. It is essential to evaluate dairy cows adaptation to their physical environment and management with the purpose of enhancing the efficiency and profitability while maintaining environmental stability. Therefore, reproduction, health, genetics, milk quality, cow comfort, and nutrition responses shall be integrated for developing decision support tools, which should include farm specific conditions such as location and seasonality.
The impacts of climate change on the economics of a dairy system have not been evaluated. Costs of production also vary across regions of the country and over time and analyses of these costs will help farm owners and lenders make better decisions related to the profitability of farms according to location, climate forecast, and market conditions. Models are available (i.e., the integrated farm system model, IFSM) to serve as platform of whole farms systematic analysis. , Data will be collected through farm surveys and official records to use and adapt existing models and to produce effective decision
Related, Current and Previous Work
Objective 1. Optimize calf and heifer performance through increased understanding of feeding strategies, management systems, well-being, productivity and environmental impact for productivity and profitability.
The NC-1042 collaborators include a core group focused on dairy replacement nutrition, management and economic efficiencies (PA, WI, MN, NH, VA, NY, KY, KS, LA, IN, SD, MI). The current NC-1042 project period 2007-2013 has seen projects contributing to the management and nutritional strategies for herd replacements under pasture or confinement conditions with implications to economic efficiencies and environmental impacts. Key areas were to further understand nutrient requirements and strategies that result in efficient growth and reduce excretion into the environment. In addition an emphasis was placed on mechanisms affecting calf health, immune function, growth, well-being and effect of environmental stressors. A continuing goal was, and continues to be, able to understand and control animal variance (Chester-Jones at al., 2008a). Comparative information on dairy heifers either raised on the home farm or under specialized contractual arrangements has been evaluated. A survey of 49 WI dairy farms and custom calf and heifer operations indicated the cost of raising dairy heifers from birth to freshening ranged from $1,595 to $2,935 (Zwald et al., 2007). This was a 58% increase since costs were calculated in 1998. Labor and management (47%) and feed (34%) were the highest costs for the calf enterprise to 9 weeks of age. Feed can account for > 51% of the heifer enterprise. Current feed costs have accelerated even further. Over the past 5 years member and non-member states have evaluated a paradigm shift in pre-weaning nutritional management of dairy calves and more emphasis on demonstration of genetic aspects related to feed efficiency to optimize calf performance and post weaning relationships to first lactation production (Soberon et al., 2012). A recent interest in organic dairy production for low input dairying and crossbreeding plus conventional systems using pasture is integral to application by member states in the project revision (Dennis et al., 2010; Murphy at el., 2011; Heins and Hansen, 2012). Active organic research dairies are in MN and NH with other grazing research opportunities in all of the core group states.
Calf passive immunity transfer (PT) from colostrum or colostrum replacers is still a critical area, which has been refined somewhat in the current project but a clear understanding of management factors and the biological processes involved needs further work. Information has been forthcoming on typical colostrum composition and management on commercial farms (Kehoe et al. 2007; Kehoe et al., 2011). A large database in MN of serum protein concentrations in 2 to 4 day-old commercial dairy heifers as indicative of PT has provided useful profiles for relationships to subsequent calf performance and health (Chester-Jones et al., 2008b). Studies on pre-partum dairy cow diets and effects on post partum colostrum immunoglobulin (Ig) absorption in calves have been conducted and will be further investigated in the next revision. Morrill et al. (2010) found that anionic salts fed in pre-partum diets had no effect on passive transfer of Ig. These authors and others have evaluated strategies for using colostrum replacers or maternal colostrum and the effect of using additives such as sodium bicarbonate or lactoferrin on Ig uptake and absorption (Shea et al., 2009; Cabral et al., 2011; Cabral et al., 2012; Chapman et al., 2012). Investigations into successful management systems to reduce calf morbidty and and the relationship to IgG absorption, calf morbidity, and mortality from birth to weaning will continue. Heat treatment of colostrum to 60 oC for 30 to 60 minutes using a batch pasteurizer reduced bacterial numbers, increased IgG absorption at 24-48 hr of age and improved calf health and performance (Elizondo-Salazar and Heinrichs, 2009; Heinrichs and Elizondo-Salazar, 2009). The dairy industry around the world has adopted this technology. There are inconsistencies in the completeness of pasteurization and quality of milk fed to calves (Godden, 2008; Elizondo-Salazar et al., 2010) requiring more studies to be done (MN, PA). VA and PA developed a spreadsheet for dairy farm managers to determine cost-effective methods of feeding milk diets up to 2 months. The model can be tested for rising or declining energy and feed costs herd size influence the investment in pasteurizers although small can save $5,000/year for pasteurizing waste milk for half of their calves although large farms will save 20 times that amount.
A number of member and non-member states have evaluated strategies for pre-weaning milk feeding including whole waste milk and milk replacers (MR; e.g., conventional, 1.25 lb of 20% protein: 20% fat MR powder daily vs. 1.5 to 2.25 lb intensive 25-28% protein: 16-25% fat MR powder daily) with implications to post weaning performance, environmental impact and subsequent lactation production (Bascom et al., 2007; Hill S. et al., 2008; Hill T.M. et al., 2008, 2009; Carlson et al., 2009, 2010; Soberon et al., 2012). Key examples included an understanding of protein/energy (51-55 g CP/Mcal ME) and essential amino acid ratios (Met:Lys, 0.31; Thr:Lys, 0.60; Met+Cys:Lys, 0.54) for milk replacer feeding programs (Hill T.M. et al., 2008, 2009). The importance of calf starter intake and formulations as part of a successful pre-weaning nutrition program has been emphasized (Ziegler et al., 2008a; Chester-Jones et al., 2010). A series of projects on feeding dairy calves from 2-4 days to 6 month in MN looking at MR and calf starter formulations to obtain benchmarks by 60 days old that double initial body weight and increased frame growth > 10 cm. Heinrichs and Heinrichs (2011) observed that during the first 16 weeks of life by Holstein calves, delivery score, weaning DMI, days of illness, days treated, grain intake at weaning, and BW at first calving had significant effects on first lactation milk production. In a MN study, the impact of conventional (20% protein: 20% fat) vs. intensive (28:16) MR feeding on pre-weaning calf performance and subsequent post weaning to 6 months in relationship to first lactation performance was evaluated (Raeth-Knight et al., 2009). Intensively fed calves had higher pre-weaning body weight and hip height vs. conventionally fed calves, no effect on milk production but reduced days to first calving by 27 days. Davis Rincker et al. (2011) observed that intensively fed calves pre-weaning tended to calf earlier but had little effect on milk production vs. a conventional system. Using genetic variation as a covariate did favor higher milk production for intensively fed calves. Further studies will focus on the genetic influence toward feed efficiency in calves as it reflects into adult animals and milk production.
Work will continue on aspects of calf feeding programs that impact rumen development (PA), specifically to address factors that account for effective fiber requirements of the neonate and developing ruminant. Traditionally, calves have been fed in individual stalls as a way to reduce health stressors. However grouping of pre-weaned calves and feeding from a common milk bar or automatic milk feeder is now considered systems that may allow more social adjustment, improved labor efficiencies and more effectively optimize calf growth (Johnson et al., 2008; Jensen, 2009). The project revision will establish specific guidelines for group feeding. The transition from individual pens to post weaned grouping has shown some health and performance challenges (Ziegler et al., 2008b; 2012). Further work is indicated in his area. An understanding of all stressors on calves will aid in refining management. Although adjustment for cold stress is well recognized, heat stress is often less understood (Williams, 2012; James and Neao, 2012).
Nutritional management for post weaned heifers has been the subject by member states to ensure that mammary development is not compromised, economic efficiencies are applied to feed costs and methods are employed to reduce environmental impact. Milk replacer formulations have been shown to affect mammary growth and composition in Holstein heifers (Daniels et al., 2009) and high energy pre-pubertal diets alter body growth and fat deposition (Davis Rincker et al., 2008). Limit feeding dairy heifers higher concentrate diets vs. typical fullfed roughage based TMR has been a focus area by member states (MS, PA, WI). These programs are able to improve feed efficiency, reduce maintenance energy requirements, and decrease nutrient excretion (Hill et al.2007; Hoffman et al., 2007; Zanton and Heinrichs, 2009 ; Kruse et al. , 2010). Limit feeding gravid heifers improved feed efficiency and reduced manure dry matter excretion without compromising lactation performance. Other nutritional strategies for growing heifers included incorporating co-product feeds into pre- and post weaning heifer diets (Suarez-Mena et al., 2011; Kalscheur et al., 2011), utilization of differing forage: concentrate ratios (Moody et al., 2007) and defining the phosphorus requirement (0.2 to 0.35%; Bjelland et al., 2011) An update of heifer growth measurements by member states will be ongoing in the project revision (PA). Other prevalent areas for the future will be an assessment of using sexed semen in dairy heifers and genomics for heifer selection in herds.
Objective 2. Improve dairy cow management decisions through nutrient utilization, well-being and profitability.
The importance of the transition period of dairy cows has been well established (Drackley, 1999). This is because negative impacts of nutrition, health, or behavior stresses over this time have long standing physiological carryover effects in the subsequent days of lactation (Overton, 2011). More specifically negative events during the transition period may affect feed intake, health, milk production and reproduction of the lactating dairy cow during the remainder of her lactation. To identify and diagnose problems during the transition period dairy producers have historically relied upon the findings from physical exams conducted by veterinarians or the information gathered through the analysis of blood samples by a diagnostic laboratory (Townsend, 2011). More recently producers have adopted their own monitoring programs, which involves managing the transitions cows as separate production groups compared with lactating cows in the remainder of the herd. Managing the transition cows as a production string allows the dairy producer to gather information on individual animals. For greater physiological insight about transition cows, producers may also employ research from NY on the use of cow-side tests for evaluating changing levels of blood metabolites, most importantly nonesterified fatty acids (NEFA) and beta-hydroxybutyrate (BHBA) or urine levels of ketones. An emerging area of research in NY and NH is the measurement and understanding of important biomarkers related in inflammation and stress of transition cows and further study is required to elucidate the physiology mechanisms involved to develop new strategies for managing transition cows (Huzzey, 2012).
Increasing costs of feeds challenges dairy farmers to optimize nutrient and energy utilization of traditional feeds or to find ways to utilize new and novels feeds and in both cases, doing it in an environmentally friendly management program. Now, more than ever, the use of a particular feed is no longer solely dictated by feed cost but also the impact on milk composition, animal health, and nutrient excretion. The increased use of corn grain for fuel ethanol production has impacted feeding strategies used on dairy farms. Research in MI, SD, and NE has evaluated the nutritional value of corn ethanol co-products and their impacts on milk production when they are used to replace traditional dairy feeds. Anderson et al. (2006) reported that when dairy cows were fed corn distillers grains and solubles (DDGS) at 20% of the ration DM, milk yield was observed to be about 2.5 kg/d higher for cows consuming DDGS compared with cows not fed DDGS. In addition, milk fat and milk protein yields were also greater for cows fed DDGS diets compared with a control diet. Likewise, Kleinschmit et al. (2006) reported that cows consuming a ration with 20% DDGS increased milk yield, 4% fat-corrected milk (FCM), and energy-corrected milk (ECM) compared with the control ration with no DDGS. Hollman et al. (2011), however, observed that the impact of DDGS on milk composition and fat yield is also related to the rumen fermentability of the ration because partially replacing high-moisture corn with DDGS increased milk fat concentration by 0.16% compared with dry corn grain. Feed markets are dynamic because prices fluctuate differently across regions and even across different feeds. Environmental pressures, for example drought, may affect amount (e.g., yield) and quality (e.g., mycotoxins) of the feed available to the dairy industry. Additionally inclusion rates of a particular feed are not always governed by their nutritional contribution to the animal but also by cost. This may lead to overfeeding of some nutrients such as nitrogen or phosphorus that when excreted, may have detrimental environmental impacts. Research on new feeds and feeding strategies, including optimization of nutrient utilization, and understanding of the impact of feed on milk production, animal health, and nutrient excretion will require new approaches and solutions.
Objective 3. Analyze whole farm system components and integrate information into decision-support tools to improve efficiency, enhance profitability, and environmental sustainability.
A. Record and Survey Analysis (MD, FL, PA, WI, KY, IN, CT)
Surveys are one of the primary methods of researching the needs of dairy producers. It is well known, for example, that dairy producers continue to operate in a highly competitive economic environment. All commodity feed prices have increased significantly in recent years. Such factors as the national renewable fuel standards and national drought in the summer of 2012 have reduced the supply of commodities commonly fed to dairy cattle, and hence profit margins have been reduced. In the future, as producers attempt to develop new management strategies to cope with the economic realities, development and analysis of financial, production, and management record databases will be necessary to determine the most efficient and sustainable systems. Various approaches are being implemented such as new cropping and feeding strategies, new technologies to improve reproduction, use of whole farm profitability assessment tools, use of precision dairy technology for monitoring behavior and health, new management practices to improve cow comfort, and use of modern calf and heifer raising systems. Robotic milking or automated milking systems are also gaining interest from dairy producers, but little U.S. research has been conducted to document and understand the specific needs that producers have in further pursuing the adoption of this technology.
In the future, dairy producers will also be challenged to focus more attention on animal care and well-being. A major step taken in this area has been the development and promotion of the National Milk Producers Federation Farmers Assuring Responsible Management (FARM) Program. Most milk marketing cooperatives have adopted the FARM program and completed audits of the dairy herds on member farms. However, research and extension programs are needed to assist producers with using the information from these audits to optimize their management and facilities for improved animal care and wellbeing.
B. Decision Support tools (WI, FL, KY, PA)
A signature trait of the NC-1042 project during the past five years has been the development and deployment of a vast number of relevant and practical use decision support tools for practical use at the farm level and for teaching applications. These tools covered almost all areas of decision-making and management in dairy farming, including price risk management (Valvekar et al., 2010; 2011); profitability and IOFC (http://extension.psu.edu/animals/dairy); precision dairy farming (Bewley et al., 2010a, b, c, d) and robotic milking systems; modernization and expansion (Cabrera and Janowski, 2011); dairy business analysis (De Vries et al., 2008; Ely et al., 2009); herd structure and replacement needs (De Vries, 2009b; Kalantari et al., 2010; Cabrera, 2010; 2012), reproductive assessments (De Vries, 2009a; Giordano et al., 2011; 2012; Kalantari et al., 2012); mastitis and health management (http://www2.ca.uky.edu/afsdairy/MilkQualityCalculator; Pinzón-Sánchez et al., 2011); genetic management (De Vries et al., 2011); and other general management tools such as the use of rbST, milking frequency, feed supplements, and accelerated calf feeding systems. Many of these tools are available at members university websites such as: FL (http://dairy.ifas.ufl.edu/tools/); KY (http://www2.ca.uky.edu/afsdairy/extension/decisiontools); PA (http://extension.psu.edu/animals/dairy); VA (http://www.vtdairy.dasc.vt.edu/tools/tool-data.html); WI (http://DairyMGT.info).
C. Precision Dairy (KY, FL, IN)
Precision Dairy Farming is the use of technologies to measure physiological, behavioral, and production indicators on individual animals to improve management strategies and farm performance. Many Precision Dairy Farming technologies, including daily milk yield recording, milk component monitoring, pedometers, automatic temperature recording devices, milk conductivity indicators, automatic estrus detection monitors, and daily body weight measurements, are already being utilized by dairy producers. Other theoretical Precision Dairy Farming technologies have been proposed to measure jaw movements, ruminal pH, reticular contractions, heart rate, animal positioning and activity, vaginal mucus electrical resistance, feeding behavior, lying behavior, odor, glucose, acoustics, progesterone, individual milk components, color (as an indicator of cleanliness), infrared udder surface temperatures, and respiration rates. The main objectives of Precision Dairy Farming are maximizing individual animal potential, early detection of disease, and minimizing the use of medication through preventive health measures. Perceived benefits of Precision Dairy Farming technologies include increased efficiency, reduced costs, improved product quality, minimized adverse environmental impacts, and improved animal health and well-being. Real time data used for monitoring animals may be incorporated into decision support systems designed to facilitate decision making for issues that require compilation of multiple sources of data. Technologies for physiological monitoring of dairy cows have great potential to supplement the observational activities of skilled herdspersons, which is especially critical as fewer skilled workers manage more cows. Moreover, data provided by these technologies may be incorporated into genetic evaluations for non-production traits aimed at improving animal health, well-being, and longevity.
D. Environmental Sustainability (WI, IN, MS)
Previous work within the multi-state group within Objectives 1 and 2 has resulted in increased feed efficiency of heifers and cows, and consequently the impact of dairy production on the environment has been reduced. The effects of these improvements on whole herd environmental impact have not been fully quantified. Specifically, differences in feed efficiency affect optimal decision-making regarding reproduction and replacement. A recent review of the literature by WI and FL has resulted in identification of gaps in existing knowledge regarding the impact of improvements in reproduction on greenhouse gas emissions. Previous work by Aguerre et al. (2012) found that an increase in 21-d pregnancy rate from 12 to 22% decreased the CH4 emission from 425 to 419 g/cow/day, but not counting CH4 emissions from young stock. CH4 emissions per kg of milk were reduced as well. Garnsworthy (2004) included CH4 emissions from young stock and calculated a 4 to 24% reduction in CH4 emissions per kg of milk, depending in the change in reproductive efficiency for adult cows. Youngstock CH4 emissions ranged from 12% to 27% of total CH4 emissions. Bell et al. (2011) and Capper and Cady (2012) reported reduced CH4 emissions per kg of milk because of a decrease in calving interval although the effects were small. Wall et al. (2012) concluded that cows with longer lactations produced less milk per day and therefore produced more CH4 per kg of milk. Yates et al. (2001), however, calculated an increase in CH4 per kg of milk when reproductive efficiency increased.
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.
MethodsObjective 1. Optimize calf and heifer performance through increased understanding of feeding strategies, management systems, well-being, productivity and environmental impact for productivity and profitability. The project revision proposes to conclude unfinished work conducted during the previous 5 years. Collaborating lead states will include NH, PA, MN, NH, MS, LA, MI, IN, SD and MD. Standard procedures for measurements and data collection will be used to allow for integration of data summaries among stations. Measurements of passive immunity transfer in postnatal calves will be documented where possible as well as calf morbidity and mortality. Calf and heifer performance, feed intake, housing and health management will be documented. Water intake and quality will be documented wherever feasible. Additional measurements may include blood metabolites and nutrient digestibility parameters. Where possible, heifer performance will be followed through first lactation. Efforts will be made to integrate animal welfare, environmental impact and economic comparisons to be included across collaborating states. All nutritional based studies will be used to validate and/or refine the current NRC (2001) requirements models. Relationships of dietary energy and protein will be described. PA and MN will take the lead with collaborating states to examine economic impact of different nutritional management strategies for dairy replacement heifers in relation to the overall herd structure and dynamics in conjunction with risk management analyses of the heifer enterprise Pre-partum dry cow management strategies to improve colostrum quality, immunoglobulin absorption, calf health and growth (NH, PA, MS, MN) NH will lead, in collaboration with PA, MS, MN, a focus on pre-partum dry cow nutritional strategies to evaluate effect on colostrum quality and absorption in newborn calves in both conventional and organic grazing systems. Calf data will be collected from commercial dairy farms to determine if certain calves are born with circulating IgG to better elucidate any potential fetal programming, genetics or cow management practices. Milking management time for collection of colostrum and effects on quality will be included. Optimizing IgG intake through manipulation of colostrum and colostrum feeding management will be addressed. Variability across seasons will be compared. PA and MN plans further work on consistency of heat-treated colostrum and effects on calf health. Best management practices for milk (whole milk and milk replacers) and starter feeding and the impact on growth, gastrointestinal development, economic efficiencies and well-being under varying environmental conditions (NH, MN, IN, PA, MS, LA) Refinement and impact of feeding strategies of conventional, moderate, and intensive milk replacers and on-farm processed milk will be addressed by all states under different environmental stressors. More succinct model definitions of cold (lead MN) and heat stress (lead LA, MS) and strategies to maintain calf performance will be assessed. MN will lead efforts to refine calf starter formulations and impact on calf performance. There are inconsistencies in the completeness of pasteurization and quality of waste milk fed to calves requiring more studies for best management practices (lead states MN, and PA). Efforts across all states will be to evaluate alternative supplements in place of antibiotics for disease and pathogen control in dairy calves. NH will lead the effort for using essential oils as an effective anticoccidial. A new project emphasis will be evaluation of pre-weaning group feeding systems will be either via multiple teat milk bar feeder or through automatic calf milk feeding units vs. individually fed calves. MN will take the lead in assessing the best management practices for using automatic calf feeders on 45 commercial operations to describe calf welfare, calf growth, effective housing designs, seasonal variation and economic impact. Organic cross-bred calves group feeding strategies via multiple teat milk bars and organic calf starters will be evaluated on the MN organic dairy herd. Work will continue on aspects of calf feeding programs that impact rumen development (PA, NH, MS, LA, IN), specifically to address factors that account for effective fiber requirements of the neonate and developing ruminant. Assessment of nutrient management, excretion, and retention in calves and heifers to determine measures of increased efficiency for conventional, organic, or grazing systems (NH, IN, MN, MS, PA, MD) Precision feeding of heifers will be a continuing emphasis in conventional systems that optimize feed efficiency and productivity, and minimize nutrient (N, P) excretion (PA, MS lead). NH, MN, MD will be lead states in evaluating efficiency of grazing systems. MN and NH will evaluate the uniqueness of organic dairy grazing systems. Specifically, MN will conduct a series of projects to compare forage quality and growth rates of organic dairy heifers grazing two different pasture systems. Nutrient management and pasture digestibility will be included. Evaluation of feed ingredients and feed management strategies on calf and heifer growth, nutrient excretion, and subsequent effects on lactation performance (MN, NH, IN, PA, MS, LA, SD). Efforts will include refinement of feeding and management strategies during the transition from individual to group housing (NH, MN lead). Utilization of high and low quality forages manipulating the degradability of protein fractions (PA lead). Co-products from the ethanol industry and feeding fat to heifers will be assessed (lead SD, MN). Cost effective feed ingredients will be prioritized. MN will lead a metanalysis of an 8 years data set to describe pre-and post weaning commercial calf feeding, growth and health up to 6 months of age to calving age and first lactation performance by season of the year. Cost effective feed ingredients will be prioritized. Objective 2. Improve dairy cow management decisions through nutrient utilization, well-being and profitability. The proposed work under this objective focuses on animal health and performance, and the evaluation of new and novel feeds to be used in dairy cow diets. Led by both NY and NH, biomarkers related to stress and inflammation during the transition period will be evaluated. Along with transition variables of health and production biomarkers such as plasma haptoglobin and fecal cortisol metabolites will be investigated to study their relationships to overall animal health and lactation performance. Research in NH will also evaluate the use of supplemental niacin on cow health. Researchers in MN and KY will investigate housing systems and strategies as they relate to transition period and beyond. The US dairy and feed industries are diverse resulting in dramatically different feeds being available in different regions. We have strategically planned studies to investigate regionally important feed related questions. In SD and NE, feeding studies will investigate the benefits of new and emerging byproducts when fed to lactating dairy cows. While in CA the nutritional value of transgenic forages for improve nitrogen utilization in diets of lactating dairy cows will be studied. Studies in SD, NE, and CA will study nutrient utilization of feeds under conventional dairy production systems while work in NH will do complimentary work under an organic dairy production system. Understanding microbial fermentation in the rumen is essential to manipulating the digestibility of news feeds and to regulating nutrient supply to metabolically active tissues to promote production, reproduction, and health of the lactating dairy cow Thus research in PA will attempt to establish how changes in concentration and physical form of fiber influences the rumen environment. Research in NE will attempt to understand the relationship between diet, the rumen microbiome, and host metabolism as it related to milk fat synthesis. In MI and NE the production of methane, a greenhouse gas linked to animal production systems, will be measured in response to changes in diet formulations or through the addition of feed additives that impact the rumen microbial population. This research is designed to shed light on methods to reduce the environmental impact of dairy production. In both SD and NE studies will attempt to understand the impact of various feeds and their nutrients on milk composition while exploring how these feeds may be included in ration formulations to maintain or increase milk fat and protein yield along with supporting nutrient and energy needs for reproduction and animal health. Research conducted in CA, SD, NH and NE will also investigate the relationship between diet, nutrient utilization in the rumen, and the fatty acid composition of milk. Lead by investigators in CA, studies are designed to track specific fatty acids such as C18:1 trans isomers and to understand how routine analysis of milk from the farm bulk tank can be used to monitor rumen function and nutrient utilization with aims to avoid metabolic syndromes (e.g., milk fat depression, and fatty liver, while increasing nutrient utilization into products including milk and meat to minimize nutrient excretion in urine, feces, and gases). Objective 3. Analyze whole farm system components and integrate information into decision-support tools to improve efficiency, enhance profitability, and environmental sustainability. A. Record and Survey Analysis (MD, FL, PA, WI, KY, IN, CT) Dairy producers need to make daily decisions about whether and when to treat, inseminate, cull, dry-off, raise, or purchase dairy cows. They need to simultaneously consider a cows future biological performance, milk, and cow prices, and herd constraints such nutrient balance or availability of labor to make the best decisions day after day. These future estimates are subject to seasonality and price and production risks. Directly associated with these complex tasks are questions about the economic value of proposed changes in management, such as reproductive management. Dairy producers and allied industries have indicated that they need support in making these complex planning decisions to improve their efficiency of production, profitability, and for the dairy industry to remain economically and environmentally sustainable. The computer programs developed in this project will enable evaluation of financial implications of the direct and indirect effects of various management options, and assist dairy producers with making effective decisions. B. Decision Support tools (WI, FL, KY, PA) Continued use of current methodologies - Several diverse methods have been used and will continue to be the signature for the creation of useful and practical decision support tools. Simulation of the long-term herd structure through Markov chains will remain to be crucial for reproductive decisions (Giordano et al., 2012); herd optimization techniques such as dynamic programming will continue to be fundamental for replacement decisions (Kalantari et al., 2010; 2012); and a combination of other herd simulation and optimization techniques are yet envisioned with the aim of respond to the ever changing needs of the dairy industry: partial budgeting, cost-benefit, decision analysis, linear programming, portfolio analysis, and Monte Carlo simulation (Dijkhuizen and Morris, 1997). New methodology - A new development will be the adoption of a standard and robust simulation and assessment methodology across locations and the inclusion of environmental components within the assessments. We will use the Integrated Farm System Model (IFSM, Rotz et al., 2011). The IFSM is a process based farm simulation model that integrates major components between biological and physical responses providing a robust research and extension tool for assessing whole dairy farm impacts of management strategies. The IFSM simulates daily crop production, crop harvesting, feed storage, herd feeding (including grazing), herd performance, manure handling, soil processes, environmental impacts, and economic performance, all integrated. It accounts for resource inputs such as fertilizers, feeds, or nitrogen fixation; resource outputs such as milk, animals, or crops sold; and losses from volatilization or runoff. Crop growth is daily predicted from soil water, nutrient availability, ambient temperature, precipitation, and solar radiation. Resource use efficiency for manure handling, tillage, cropping, and harvesting operations are functions of size and type of machines and weather. Field drying rate, harvest losses, and nutritive changes in crops depend upon weather, crop conditions, and operations machinery. Losses and nutritive changes of feeds are forecast from harvested crop characteristics and type and size of storage facility. The IFSM simulates up to 6 dairy cow groups, each one with their own nutritive requirements. Diets for each group are formulated using a cost-minimizing algorithm that optimizes the use of homegrown feeds and purchased supplements. Manure produced by animals is used as soil fertilizer according to facilities, machinery, and rules defined by farm management. Whole farm nutrient balances determine nutrient accumulation in soil and losses to the environment for N, P, K, and C. The IFSM reports net emissions of greenhouse gases. It also calculates net economic returns as the difference of revenues from milk, animals, and excess feeds sales and costs, including equipment and facilities, supplemental feed, labor, and other production resources. The use of the IFSM will allow different NC-1042 locations to replicate assessments and study differences among diverse systems. Importantly, it will give new dimensions to the analyses because it will include other components of the dairy farm system and their interactions such as crops, grazing operations, environmental impacts, among many others, which have not been used before. C. Precision Dairy (KY, FL, IN) The aims of the work focused on Precision Dairy technologies are is to evaluate the ability of Precision Dairy Farming technologies to accurately detect estrus and to identify early stages of diseases when compared to conventional monitoring. To examine this question, data obtained from technologies must be compared to biological data more commonly available. For example, mastitis detection technologies will be evaluated by comparing results from somatic cell count and bacteriological culture tests. Similarly, metabolic disease detection technologies will be compared to blood chemistry profiles. Estrus detection technologies will be compared to luteinizing hormone and progesterone profiles and ultrasound confirmation of ovulation. For these technologies to provide meaningful data to producers, they must provide actionable information in a timely manner to producers. Efforts at each station aim to evaluate the efficacy of multiple Precision Dairy technologies. Perceived economic returns from investing in a new technology are a major consideration influencing Precision Dairy Farming technology adoption. Bewley et al. (2010a) have developed a dynamic, stochastic, mechanistic simulation model of a dairy enterprise to evaluate the cost and benefit streams coinciding with investments in Precision Dairy Farming technologies, which will be adjusted for continued assessments. The model was constructed to embody the biological and economical complexities of a dairy farm system within a partial budgeting framework. The basic deterministic model was created in Microsoft Excel (Microsoft, Seattle, WA). The @Risk add-in (Palisade Corporation, Ithaca, NY) for Excel was employed to account for the stochastic nature of key variables within a Monte Carlo simulation. D. Environmental Sustainability (WI, IN, MS) The proposed methods include extensions of the dairy herd models developed earlier by the group members with greenhouse gas emissions of individual animals. By penalizing total herd greenhouse gas emissions, the dairy herd models will be used to optimize insemination and replacement decisions considering the environmental impact. Group members will use the same dairy herd models to calculate the environmental impact of improvements in feed efficiency in dairy heifers and cows.
Measurement of Progress and Results
- Objective 1: Best management feeding strategies for dairy calves (individual vs. group) and heifers based on diet environmental stressors (heat vs. cold stress) and minimal environmental impact will be implemented by dairy producers
- Objective 1: Impact of best management practices that subsequently improve the lactation performance will be described
- Objective 1: Alternate treatments for diseases that could be utilized by dairy producers following organic dairy management practices will be utilized to control and prevent calfhood disease
- Output 6, Objective 1: Risk evaluations will be assessed for dairy heifer replacements to describe economic efficiencies of system options Output 7, Objective 2: Increased milk production, reduced feed costs, improved milk quality, improved nutrient utilization in the animal, improved feed efficiency, improved well-being and animal health, reduced impact of animal agriculture on the environment will be promoted through the publication and dissemination of results of scientific trials Output 8, Objective 3A: Results of surveys conducted in each state will be published in extension factsheets and peer-reviewed journals. Additionally, survey results will be presented at regional and national meetings in an effort to communicate farmer-based outcomes. Decision support tools and accompanying user guides will be published online for dairy producers and their advisors to access Output 9, Objective 3B: The use and application of the IFSM in conjunction with already developed tools for dairy farm decision-making will allow: 1) devising rules of thumb or general messages that consistently could be recommended to all dairy farm systems for improved economic and environmental sustainability; and 2) development of new decision support tools that devise management interactions according to specific dairy farm management systems and therefore producing best management practices according to locations and different systems Output 10, Objective 3C: Technology evaluations, with specific emphasis on sensitivity and specificity for detecting an event of interest (estrus or disease) will be published in peer reviewed journals. Extension factsheets to help producers evaluate technology investment decisions will be developed. The investment analysis decision tool will be published online Output 11, Objective 3D: Provide management and nutritional recommendations for transition and lactating cows to be integrated into whole-herd analyses and decision support models. Develop decision support systems for dairy producers and their advisors to aid in making profitable and environmentally sustainable on-farm decisions.
Outcomes or Projected Impacts
- Objective 1: Dairy farmers calves will be healthier due to improved feeding protocols of their dam. Calves will also be healthier due to improved colostrum management and feeding methods. Research will help elucidate better ways to harvest, store and feed colostrum to improve calf health and ultimately enhance milk production and profits for the producer.
- Objective 1: A better understanding of the use of colostrum replacers and supplements will be realized. Calves will be fed milk and milk replacer correctly to optimize growth while not hindering future performance. Calf rearing environment will help dictate how calves are fed. New treatments will be available for dairy producers to help control calf diseases.
- Objective 1: Heifer raisers will have information to be able to maximize both nutritional and economic efficiencies. Graziers will understand how to correctly supplement heifers while on pasture. Results from this project will increase the profits for dairy producers through modifying their calf and prepartum cow feeding and management practices
- Objective 2: Improving health will improve nutrient utilization and N in the environment. Healthier cows will reduce culling rates and improve production efficiency by keeping cows in the milk string longer to dilute the cost of maintenance. Increased use of a by-product feeds that are often lower in price and locally produced forages. Indirectly, research will result in reduced competition dairy animal agriculture and human populations for feed/food resources in less reliance of feed and food stocks or world feed supply
- Objective 2: Manipulation of fatty acid content of milk may lead to methods to improve human health through the understanding of synthesis of bio-active fatty acids, CLA, and oleic acid.
- Outcome/Impact 6, Objective 3: Dairy farmers will improve their overall production efficiency and therefore their long-term economic and environmental sustainability through enhanced whole farm management strategies that will result by adopting and applying decision support tools developed and made available through this project efforts
Milestones(2014): Objective 1: Coordinate design of collaborative procedures for calf and heifer studies and outline specific goals. Objective 2: Calibrate equipment; develop techniques, train staff and students. Objective 3: Conduct surveys, develop decision support tools, adoption of IFSM model, initialization of of new precision dairy studies, and start studies of feed efficiency on green house gas emissions
(2015): Objective 1: Implement heifer studies and communicate progress across collaborators. Objective 2: Conduct field trials. Objective 3: Conduct surveys and release previous years results, develop decision support tools, start analyses with IFSM, continue precision dairy studies, and continue studies of feed efficiency on green house gas emissions.
(2016): Objective 1: Continue heifer studies and communicate progress across collaborators. Objective 2: Continue conducting field trials. Objective 3: Conduct surveys and release previous years results, develop decision support tools, continue analyses with IFSMl, evaluate of precision dairy studies will continue and previous assessment will be published, and continue updating existing dairy herd models with greenhouse gas emission attributes and start optimizing decision-making.
(2017): Objective 1: Complete collection data analyses. Objective 2: Evaluate samples and analyze data from previous studies. Objective 3: Conduct surveys and release previous years results, develop decision support tools, continue analyses with IFSM including data from different stations, evaluation of precision dairy studies will continue and previous assessment will be published, the investment analysis model will be published online, and the greenhouse gas emission decision support software will be finished and made available to stakeholders.
(2018): Objective 1: Complete write up, validate field studies, finalize specific software and worksheets and disseminate information. Objective 2: Complete write up, validate field studies, disseminate information. Objective 3: summarize all analysis from survey results, release and disseminate all decision support tools developed by project including models that include IFSM assessments across stations, summary of all precision dairy studies will be released together with decision support tools, and results from the greenhouse gas emissions assessments will be published in popular press and scientific literature.
Projected ParticipationView Appendix E: Participation
Most of the NC-1042 members and all the members directly involved in Objective 3 have an Extension appointment, which is envisioned to be the primary channel of information dissemination. Annual project meetings and additional small group virtual meetings are to be used to share developments and results and promote diffusion of innovations to those who need the most. Additional means of outreach will be through national eXtension webinars and publications, Hoards magazine articles and webinars, and factsheets and brochures targeted to the dairy industry providers and dairy industry farm consultants. Results will be presented at scientific meetings and published in scientific journals. Spreadsheets, software programs and decision support models will be made available as apps for smartphones, tablets and online. Some additional specifics means of dissemination are outlined below:
" Validate and refine existing models of nutrient requirements of calves and heifers and present study results at scientific meetings and published in scientific journals, extension fact sheets and popular press
" Present symposium at the ADSA Midwest Section meetings to facilitate information transfer and obtain input for future research directions and to attract outstanding graduate students to research programs.
" Participate in applied workshops within states and organize regional and national workshops
" Distribute spreadsheets, software programs and decision support models based on outcomes for risk assessment and potential management actions
" Distribute all pertinent information through the national eXtension and other websites.
The Projects Technical Committee shall consist of officially-designated representatives from each participating Agricultural Experiment Station and USDA group, regional administrative advisor (non-voting), and NIFA representative (non-voting). Participating stations and groups are those written into the regional project or have an approved addendum.
Projects officers shall be chairperson and secretary. A secretary shall be duly elected at the conclusion of the annual meeting of the Technical Committee and automatically succeed to the position of chairperson one year later. The Executive Committee shall consist of chairperson, secretary, and immediate past-chairperson. Executive committee, in conjunction with the Administrative Advisor, is authorized to function on behalf of the Technical Committee in all matters pertaining to the regional project requiring interim action. The chairperson, in consultation with the Administrative Advisor, shall arrange the time and place of meetings, prepare the agenda, preside at meetings of the Technical Committee, and is responsible for preparation of the annual progress report. The secretary records minutes, compiles station reports, and performs other duties as assigned by the Technical Committee or Administrative Advisor. Subcommittees will be appointed by the chairperson to complete specific assignments and to monitor progress within each of the main objectives. Subcommittees will meet at least once prior to or during the annual Technical Committee meeting.
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