This webinar shares research and guidance on minimizing the risk of virus movement through manure and mortality management. This webinar also explains the roles technical advisors can play in response to an outbreak. This presentation originally broadcast on March 17, 2023. Continue reading “Moving Manure and Mortalities after Highly Pathogenic Avian Influenza”
Composting can reduce antimicrobial resistance in manure
A brief summary of the manuscript, Dissipation of Antimicrobial Resistance Determinants in Composted and Stockpiled Beef Cattle Manure by Xu et al. (2016)
Key Points:
- Composting manure can reduce pathogen presence and antimicrobial residues in manure.
- Composting efficacy in reducing antimicrobial residues in manure is associated with elevated temperatures within the composting process.
- Stockpiling manure marginally reduce pathogen presence and antimicrobial residues in manure when compared to composting.
Continue reading “Composting can reduce antimicrobial resistance in manure”
Human Health: Pathogens and Contaminants in Livestock Systems
This webinar provides practical guidance on reducing pathogen and inhalation exposures in livestock operations and identifies ways to protect human health and those we love. This presentation was originally broadcast on May 15, 2020. More… Continue reading “Human Health: Pathogens and Contaminants in Livestock Systems”
Managing Manure to Mitigate Antibiotic Resistance
This webinar highlights some of the work being done to identify effective practices for reducing concentrations of resistant bacteria and resistance genes at critical control points in beef feedlot and dairy manure management systems. This presentation was originally broadcast on November 15, 2019. More… Continue reading “Managing Manure to Mitigate Antibiotic Resistance”
Reduction and fate of manure pathogens and antimicrobial resistance
Antimicrobial resistance is a complex issue as it is comprised of not only pathogenic bacteria, but also non-pathogens which share genes within complex environmental systems, such as agricultural fields. This webinar describes potential measures to reduce pathogen and antimicrobial resistance in manure as well as potential fate and transport of manure pathogens and antimicrobial resistance following land application of manure. This presentation was originally broadcast on May 17, 2019. More… Continue reading “Reduction and fate of manure pathogens and antimicrobial resistance”
Winter Manure Application: Research Needs and Future Direction
To better understand the state of the science and to lessen the present risk of winter manure application, a literature review was conducted that examined a wealth of studies dating back to 1945. Interest in winter manure application has increased, in part, due to the high-profile nutrient impacts to the Great Lakes and the several resulting new policies that have been implemented within the surrounding states. Based on this literature review, research needs and future directions were identified.
What did we do?
A comprehensive literature review was conducted that included scientific, technology transfer, and regulatory documents. Contaminants of concern, emerging pollutants, case studies, existing best management practices, state level policy, and key data gaps were identified.
What we have learned?
The US Environmental Protection Agency (EPA) and the Natural Resource Conservation Service (NRCS) discourages the application of manure in winter because of the elevated risk of nutrient loss to the environment as demonstrated by several field, laboratory, and modeling studies (Srinivasan et al., 2006). The emergence of environmental issues downstream of livestock operations such as algae blooms and fish kills has led some States to ban winter manure application all together, although some states still allow emergency applications and exempt smaller farms from the regulations. Additionally, the loss of nutrients during spring thaws means a loss of soil productivity for farmers and added expense to purchase soil amendments.
There are several parameters that ultimately determine the impact winter manure spreading will have on the environment and the nutrient content that remains in the soil after application. Included, but not limited to, are slope, soil type, depth of freeze, rate of thaw, depth of snow, presence of cover crops, tilling practices, manure moisture content, and timing of application. Several are interdependent, often resulting in difficulty isolating the relative effects of any particular parameter compared to another and, in some cases, contradictory research results are found. However, several general findings may still be derived, as discussed below.
Nutrients
Runoff from winter-applied manure can be an important source of annual nutrient loadings to water bodies, with nitrogen and phosphorous being the most often reported. In a 1985 study, Moore and Madison (1985) estimated that 25% of annual phosphorus load to a Wisconsin lake was directly attributable to winter spreading of animal wastes. Brown et al. (1989) investigated the Cannonsville Reservoir in New York and determined that snowmelt runoff from winter manured cropland contributed more phosphorus to the reservoir than runoff from barnyards. Clausen and Meals (1989) estimated that 40% of Vermont’s streams and lakes experienced significant water quality impairments from the addition of just two winter-spread fields in their watersheds. Plot studies of winter-applied manure found 23.5 to 1,086 mg/L of total Kjeldahl nitrogen (TKN) and 1.6 to 15.4 mg/L of phosphorus in runoff (Lorimor and Melvin, 1996; Thompson et al., 1979). In two Vermont field studies, Clausen (1990; 1991) reported 165 to 224% increases in total phosphorus concentration, 246 to 1,480% increases in soluble phosphorus, 114% increases in TKN, and up to a 576% increase in NH3-N following winter application of dairy manure. Mass losses of nutrients are highly variable across studies. Several studies have noted elevated, though moderate, mass losses of nitrogen ranging from 10-22% of applied nitrogen (Converse et al., 1976; Hensler et al., 1970; Klausner et al., 1976; Lorimor and Melvin, 1996; Midgley and Dunklee, 1945; Phillips et al., 1981). However, Owens et al. (2011) reported total nitrogen losses of 35-94%, by mass. These numbers are highly variable due the extreme variance in weather conditions, with flash events contributing more nutrient loss than slower melt events. Authors noted that it is possible for nearly all loss to occur in a single storm event (Klausner et al., 1976; Owens et al., 2011).
Steenhuis et al., (1979) reported decreases in ammonia volatilization rates for winter spread manure relative to spring due to lower temperatures. Lauer et al. (1976) showed that manure covered by snow had no signs of ammonia volatilization. These results suggested that limiting ammonia volatilization may be critical to nutrient retention in soil. However, Williams et al. (2010) showed that manure applied under snow did not truly maintain this ammonia but lost it through runoff. No case studies have quantified the reduction of other odor causing compounds such as di-hydrogen sulfide in winter applied manure relative to other seasonal applications.
Losses are contingent upon fields exhibiting certain risk factors (Klausner et al., 1976; Young and Holt, 1977; Young and Mutchler, 1976). Important are variations in local weather conditions, depth and type of soil freeze, the position of manure relative to the snowpack, and the timing of application relative to snow melt. Because of the large number of unconstrained variables in the natural environment, there continue to be disagreements on best management practices to limit nutrient movement. Additionally, the form of nutrient is critical. All of these factors impact the mechanisms of nutrient loss: plant uptake, sorption, polymerization, microbial degradation, volatilization, advective movement, and dispersive transport. Consequently, the fate of particulate forms may be very different than soluble, depending on the site and management-specific conditions.
As such, the industry will benefit from continued experiment and field research in an effort to account for very specific, definable variables and nutrient form. Further, because of the extensive list of relevant variables, the development of precise and accurate mathematical models is essential as experimentally modeling the infinite number of site and management-specific conditions is impossible.
Pathogens
Several varieties of pathogens are common in livestock excrement, though not all pose human health risks. Pathogens of concern include the following (USEPA 2004; Rogers and Haines 2005; Sobsey et al. 2006; Pappas et al. 2008; Bowman 2009).
- Bacteria: Escherichia coli (E. coli) O157:H7 and other shiga-toxin producing strains, Salmonella spp., Campylobacter jejuni, Yersinia enterocolitica, Shigella sp., Listeria monocytogenes, Leptospira spp., Aeromonas hydrophila, Clostridium perfringens, Bacillus anthraxis (in endemic area) in mortality carcasses.
- Parasites: Giardia lamblia, Cryptosporidium parvum, Balantidium coli, Toxoplasma gondii, Ascaris suum and lumbricoides, Trichuris trichuria.
- Viruses: Rotavirus, hepatitis E virus, influenza A (avian influenza virus), enteroviruses, adenoviruses, caliciviruses (e.g., norovirus).
As with nutrients, application of animal manure to impervious surfaces such as frozen ground can increase the risk of pathogen loss through runoff events relative to application in other seasons (Reddy, et al., 1981). Cool temperatures have been shown to improve the survival of fecal bacteria (Reddy et al., 1981; Kibbey, et al., 1978). However, field studies found that freezing conditions can be lethal to fecal bacteria (Kibbey, et al., 1978). While these reports hint at fecal bacteria being able to survive cool but not freezing conditions, Kudva, et al. (1998) reported E. coli surviving more than 100 days in manure frozen at minus 20°C. Conversely, freezing and thawing of a soil manure mixture was found to reduce E. coli levels by about 90% (Bicudo, 2003).
More research on this topic is needed to identify conflicting results. Of particular interest is the impact of warming soil temperatures. Slight variations can result in substantial microbial ecological changes. Further, it is well understood that the use of fecal coliform as a pathogen indicator is flawed. New microbial genetics techniques enable the identification of pathogens of greatest risk. Research should monitor for these specific, likely pathogens and their fate during freeze-thaw cycles.
Emerging Pollutants
Land application of both solid and slurry excrement has been cited as a vector for introduction of antimicrobials into the environment (Boxall 2008; Klein et al. 2008). In the early 2000s, it was estimated that approximately 60% to 80% of livestock and poultry routinely received antimicrobials through feed or water, injections, or external application (NRC 1999; Carmosini and Lee 2008). Though new best management practices involving non-therapeutic use of antibiotics in livestock are likely to decrease these percentages, estimated changes are not available. Livestock animals are estimated to discharge 70-90% of antibiotics administered through excrement (Massé et al., 2014). Approximately 55% of antimicrobial compounds administered to livestock and poultry are also used to treat human infections (Benbrook 2001; Kumar et al. 2005; Lee et al. 2007). The utilization of such overlapping antibiotics has been cited as a potential cause of antimicrobial resistance (Sapkota et al. 2007), a grave concern in modern medicine (Levy and Marshall 2004; Sapkota et al. 2007).
Antimicrobials are hydrophilic and do not readily break down in the environment and are, consequently, at high risk of introduction into water bodies through runoff events (Chee-Sanford et al. 2009; Zounková et al. 2011). Critically, these compounds show high adsorptive tendencies in soils and clays (Chee-Sanford et al. 2009), thus providing a potential for interception by soil.
Because antibiotics are highly hydrophilic, movement with melt water results, similar to soluble nutrients. Although this mechanism seems clear, movement during winter application is poorly understood. The mechanisms that determine their fate are the same as those listed for nutrients. However, this fate is poorly understood, especially regarding the amount that will reach the field and streams when comparing different seasonal applications. Further, some studies suggest prolonged storage in aerobic manure environments helps facilitate breakdown particularly at higher temperatures (Kumar et al. 2005; Lee et al. 2007; Boxall et al. 2008). However, the question remains whether these effects are present in winter storage.
Fate studies under diverse farm field conditions are essential. Further, the original compound may be broken down into metabolites, some of which may be even more dangerous. All original and breakdown products should be reviewed.
Benefits of Winter Manure Application
The soil health benefits of winter manure application appear to be limited. However, the literature suggests that soil compaction and nitrogen volatilization can be reduced when applying to frozen soil, but at the potential expense of nutrient runoff. There are also many benefits to agriculturalists, as Fleming and Fraser (2000) noted:
- Reducing size and number of manure storage structures.
- Spreading the manure when logistics suite the farmer.
- Reducing soil compaction by avoiding equipment use during compressible soil conditions.
Management Practices
There is little standardization in regard to winter manure application and most states cite the NRCS conservation practice standard 590 for nutrient management (NRCS, 2013). In regard to winter manure application, this standard states the following. “Nutrients must not be surface-applied if nutrient losses offsite are likely. This precludes spreading on: frozen and/or snow-covered soils, and when the top two inches of soil are saturated from rainfall or snow melt. Exceptions for the above criteria can be made for surface-applied manure when specified conditions are met and adequate conservation measures are installed to prevent the offsite delivery of nutrients” (NRCS, 2013). As a continuation of standard 590, the NRCS states that at a minimum the following factors should be considered before winter manure application (NRCS, 2013):
- Field slope
- Organic residue and living covers
- Amount and form of nutrients to be applied
- Setback distances to protect local water quality
- Application timing
The ambiguity in standard practices for winter manure application has led to several different State policies. States with winter manure application guidelines include Ohio, Pennsylvania, Michigan, and Illinois. States that have some form of bans include Vermont, Iowa, Maryland, Indiana, Minnesota, and Wisconsin. States not listed have policies that are identical to the NRCS standard 590.
Future Plans
Based on this literature review, needed research has been identified:
- Review the incidences of emergency spreading on frozen ground versus incorporation during cold weather. Understanding the frequency and timing of emergency spread events is critical to crafting policy and best management practices.
- Evaluate compliance with new rules and if intended impacts are realized, including comparing watershed level of target pollutants across state lines and time lines to view the impacts of this policy change.
- Determine if application in early spring, when soil is saturated and precipitation events are frequent, is more desirable than in winter application before a deep freeze allows for incorporation. Related is the impact of soil moisture content on the fate of target pollutants during thaw events.
- Determine the economic impact on producers and the potential loss of small to medium sized farms. One of the most often cited criticisms of unconditional winter manure application bans is that it can disproportionately disadvantage smaller producers. In a Michigan survey of small producers, 27% of non-CAFO dairy farmers suggested that they would need to suspend operations if such a ban were instituted (Miller et al., 2017). This same survey found that a total ban on winter application in Michigan would collectively cost small farms in that state an estimated $30 million dollars (Miller et al., 2017). An important task is to survey, with time, states that have banned winter manure application to determine if significant shift with regard to average producer size occurred. If so, it is important to consider the resulting economics of the environmental benefits and if national biosecurity decreased with a reduction in producers.
- Verify the effectiveness of risk indices such as the Manure Application Risk Index (MARI), Wisconsin’s Online Manure Advisory System, and other individual states’ P-indices. Many of these indices were developed based on recommendations from research and the practical experience of experts, but literature verifying this is scarce.
- Determine the impact of climate change on winter manure application policies. Climate change effects the duration and intensity of winter temperatures and the frequency and intensity of precipitation events. Such conditions may require more adaptable metrics such as frost depth, depth of snow, ability to incorporate, and forecasted thaw events.
Authors
Steven I. Safferman1, Jason S. Smith2, and Rachelle L. Crow3
1Associate Professor; Michigan State University, Biosystems and Agricultural Engineering; Corresponding Author: SteveS@msu.edu
2Teaching Specialist, Michigan State University, Engineering CoRe
3Undergraduate Research Assistant, Michigan State University, Biosystems and Agricultural Engineering
Additional information
- Benbrook, C.M. 2001. Quantity of antimicrobials used in food animals in the United States. American Society for Microbiology 101st Annual Meeting. May 20-24, 2001. Orlando, FL.
- Bicudo, J. R., Goyal, S.M. 2003. Pathogens and manure management systems: a review. Environmental technology 24.1 (2003): 115-130.
- Bowman, J. 2009. Manure pathogens: manure management, regulations, and water quality protection. p. 562.Water Environmental Federation, McGraw-Hill, New York.
- Boxall, A. 2008. Fate and transport of veterinary medicines in the soil environment. p 123-137. In D.S. Aga (ed.) Fate and transport of pharmaceuticals in the environment and water treatment systems. 1st ed. CRC Press, Boca Raton, FL.
- Brown, M.P., Longabucco, P., Rafferty, M.R., Robillard, P.D., Walter, M.F., Haith, D.A. 1989. Effects of animal waste control practices on nonpoint-source phosphorus loading in the West Branch of the Delaware River watershed. J. Soil Water Conserv. 44, 67–70.
- Carmosini, N., Lee, L.S. 2008. Sorption and Degradation of selected pharmaceuticals in soil and manure. p 139-165. In D.S. Aga (ed.) Fate and transport of pharmaceuticals in the environment and water treatment systems. 1st ed. CRC Press, Boca Raton, FL.
- Chee-Sanford, J.C., Mackie, R.I., Koike, S., Krapac, I.G., Lin, Y., Yannarell, A.C., Maxwell, S., Aminov. R.I. 2009. Fate and transport of antibiotic residues and antibiotic resistance genes following land application of manure waste. Journal of Environmental Quality. 38(3):1086-1108.
- Clausen, J.C. 1990. Winter and Fall application of manure to corn land. Pages 179 – 180 invMeals, D.W. 1990. LaPlatte River Watershed Water Quality Monitoring and AnalysisProgram: Comprehensive Final Report. Program Report No. 12. Vermont WatervResource Research Center, University of Vermont, Burlington.
- Clausen, J.C. 1991. Best manure management effectiveness. Pages 193 – 197 in Vermont RCWP Coordinating Committee. 1991. St. Albans Bay Rural Clean Water Program, Final Report. Vermont Water Resources Research Center, University of Vermont, Burlington
- Clausen, J.C., Meals, D.W. 1989. Water quality achievable with agricultural best management practices. J. Soil Water Conserv. 44, 593–596.
- Converse, J.C., Bubenzer, G.D., Paulson, W.H. 1976. Nutrient losses in surface runoff from winter spread manure. Trans. ASAE 19, 517–519.
- Fleming, R., Fraser, H. 2000. Impacts of winter spreading of manure on water quality: Literature review. Ridgetown, Ontario, Canada Ridget. Coll. Univ. Guelph.
- Hensler, R.F., Olsen, R.J., Witzel, S.A., Attoe, O.J., Paulson, W.H., Johannes, R.F. 1970. Effect of method of manure handling on crop yields, nutrient recovery and runoff losses. Trans. ASAE 13, 726–731.
- Kibbey, H.J., Hagedorn, C., and McCoy, E.L. 1978. Use of fecal streptococci as indicators of pollution in soil. Applied Environmental Microbiology. 35:711-717.
- Klausner, S.D., Zwerman, P.J., Ellis, D.F. 1976. Nitrogen and phosphorus losses from winter disposal of dairy manure. J. Environ. Qual. 5, 47–49.
- Klein C., O’Connor, S., Locke, J., Aga, D. 2008. Sample preparation and analysis of solid-bound pharmaceuticals. p. 81-100. In D.S. Aga (ed.) Fate and transport of pharmaceuticals in the environment and water treatment systems. 1st ed. CRC Press, Boca Raton, FL.
- Kudva, I. T., Blanch, K., Hovde, C. J. 1998. Analysis of Escherichia coli O157: H7 survival in bovine or bovine manure and manure slurry. Applied and environmental microbiology, 64(9), 3166-3174.
- Kumar, K., Gupta, S.C., Chander, Y., Singh, A.K. 2005. Antibiotic use in agriculture and its impact on the terrestrial environment. Advances in Agronomy. 87:1-54.
- Lauer, D.A., Bouldin, D.R., Klausner, S.D. 1976. Ammonia volatilization from dairy manure spread on the soil surface. J. Environ. Qual. 5, 134–141.
- Lee, L.S., Carmosini, N., Sassman, S.S., Dion, H.M., Sepúlveda, M.S. 2007. Agricultural contributions of antimicrobials and hormones on soil and water quality. Advances in Argronomy.93:1-68.
- Levy, S.B., Marshall, B. 2004. Antibacterial resistance worldwide: causes, challenges and responses. Nature Medicine Supplement. 10(12):S122-S129.
- Lorimor, J.C., Melvin, J.C. 1996. Nitrogen losses in surface runoff from winter applied manure. Final Report. Univ. Iowa, Ames, Iowa.
- Massé, I.D., Saady, M.N., Gilbert, Y. 2014. Potential of Biological Processes to Eliminate Antibiotics in Livestock Manure: An Overview. Anim. . doi:10.3390/ani4020146
- Midgley, A.R., Dunklee, D.E. 1945. Fertility runoff losses from manure spread during the winter. Agricultural Experiment Station; Burlington.
- Miller, S.R., Mann, J.T., Leschewski, A., Rozeboom, D., Safferman, S., Smith, J. 2017. Survey of Small Michigan Livestock Winter Manure Handling and Economic Assessment of Policy Change, in: 2017 ASABE Annual International Meeting. American Society of Agricultural and Biological Engineers, p. 1.
- Moore, I.C., Madison, F.W. 1985. Description and application of an animal waste phosphorus loading model. J. Environ. Qual. 14, 364–369.
- NRC. 1999. The use of drugs in food animals: benefits and risks. Food and Nutrition Board, Institute of Medicine. National Academy Press, Washington, DC.
- NRCS. 2013. Conservation Practice Standard 590: Nutrient Management [WWW Document]. URL https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb1192371.pdf (accessed 1.8.17).
- Owens, L.B., Bonta, J. V, Shipitalo, M.J., Rogers, S. 2011. Effects of winter manure application in Ohio on the quality of surface runoff. J. Environ. Qual. 40, 153–165.
- Pappas, E. A., Kanwar, R. S., Baker, J. L., Lorimor, J. C., Mickelson, S. 2008. Fecal indicator bacteria in subsurface drain water following swine manure application. Transactions of the ASABE, 51(5), 1567-1573.
- Phillips, P.A., Culley, J.L.B., Hore, F.R., Patni, N.K. 1981. Pollution potential and corn yields from selected rates and timing of liquid manure applications. Trans. ASAE 24, 139–144.
- Reddy, K. R., Khaleel, R., Overcash, M. R. 1981. Behavior and transport of microbial pathogens and indicator organisms in soils treated with organic wastes. Journal of Environmental Quality, 10(3), 255-266.
- Rogers, S., and J. Haines. 2005. Detecting and mitigating the environmental impact of fecal pathogens originating from confined animal feeding operations: review. EPA-600-R-06-021. USEPA, Office of Research and Development, National Risk Management Research Laboratory. Cincinnati, OH.
- Sapkota, A.R., F.C. Curriero, K.E. Gibson, and K.J. Schwab. 2007. Antibiotic-resistant enterococci and fecal indicators in surface water and groundwater impacted by a concentrated swine feeding operation. Environmental Health Perspectives. 115(7):1040-1045.
- Sobsey, M.D., Khatib, L.A., Hill, V.R., Alocilja, E., Pillai, S. 2006. Pathogens in animal wastes and the impacts of waste management practices on their survival, transport and fate. p. 609-666. In J.
- Srinivasan, M.S., Bryant, R.B., Callahan, M.P., Weld, J.L. 2006. Manure management and nutrient loss under winter conditions: A literature review. J. Soil Water Conserv. 61, 200–209.
- Steenhuis, T.S., Bubenzer, G.D., Converse, J.C. 1979. Ammonia volatilization of winter spread manure. Trans.of ASAE. p 152-157, 161.
- Thompson, D.B., Loudon, T.L., Gerrish, J.B. 1979. Animal manure movement in winter runoff for different surface conditions, in: Best Management Practices for Agriculture and Silviculture Proceedings of the 1978 Cornell Agricultural Waste Management Conference, P 145-157, 1979. 1 Fig, 4 Tab, 16 Ref.
- USEPA. 2004. Risk management evaluation for concentrated animal feeding operations. EPA-600-R-04-042.USEPA, Office of Research and Development, National Risk Management Research Laboratory, Cincinnati, OH.
- Williams, M.R., Feyereisen, G.W., Beegle, D.B., Shannon, R.D., Folmar, G.J., Bryant, R.B. 2010. Manure application under winter conditions: Nutrient runoff and leaching losses, in: 2010 Pittsburgh, Pennsylvania, June 20-June 23, 2010. American Society of Agricultural and Biological Engineers, p. 1.
- Young, R.A., Holt, R.F. 1977. Winter-applied manure: Effects on annual runoff, erosion, and nutrient movement. J. Soil Water Conserv.
- Young, R.A., Mutchler, C.K. 1976. Pollution potential of manure spread on frozen ground. J. Environ. Qual. 5, 174–179.
- Zounková, R., Klimešová, Z., Nepejchalová, L., Hilscherová, K., Bláha, L. 2011. Complex evaluation of ecotoxicity and genotoxicity of antimicrobials oxytetracycline and flumequine used in aquaculture. Environmental Toxicology and Chemistry, 30(5), 1184-1189.
Acknowledgements
This project was funded by the North Central Regional Water Network Manure and Soil Heath Working Group and the Soil Health Institute.
The references for the original reports follow:
- Smith, J.S., Safferman, S.I. 2018. Winter Manure Application: Research Needs and Future Direction. North Central Region Water Network, Soil Health Nexus.
- Smith, J.S., Crow, R., Safferman, S.I. 2018. Winter Manure Application: Management Practices and Environmental Impact. North Central Region Water Network, Soil Health Nexus.
- Smith, J.S., Crow, R., Safferman, S.I. 2018. Winter Manure Literature Review – Document Summaries. North Central Regional Water Network, Soil Health Nexus.
The authors are solely responsible for the content of these proceedings. The technical information does not necessarily reflect the official position of the sponsoring agencies or institutions represented by planning committee members, and inclusion and distribution herein does not constitute an endorsement of views expressed by the same. Printed materials included herein are not refereed publications. Citations should appear as follows. EXAMPLE: Authors. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.
Manure Land Application Strategies to Mitigate Antibiotics and Antibiotic Resistance Genes in the Agricultural Environment
When it comes to the land application of livestock manure, a major environmental concern is the loss of manure-borne nutrients to surface runoff. Management practices and regulations focus on how nutrients travel in runoff as functions of the timing and method of land application as well as proximity to water sources. When manure is applied to soil, manure constituents other than nutrients are also introduced to soil, such as heavy metals, antibiotics, and antibiotic resistance genes. Knowledge about the behaviors of these manure constituents in the environment as a function of manure application strategies is limited.
In this article we will discuss the effects of various land application strategies on the fate and transport of manure borne antibiotics and antibiotic resistance genes in soil and runoff. This will be broken down into three sections: manure storage; land application methods; and vegetative barrier. Although our studies were conducted using swine manure slurry, it is expected that that the general conclusion would also apply to other types of manure. Prior to a detailed description of our findings, we will first present some background information about manure-borne antibiotics and antibiotic resistance genes.
Why Care About Antibiotics?
Antibiotics are often used in concentrated animal feeding operations (CAFOs) to prevent and treat diseases in livestock animals, increasing the density at which livestock can be kept. A substantial portion of these antibiotics can move thorough the digestive system of livestock, and end up in livestock urine and feces. These antibiotics can persist in the livestock manure and go on to alter the microbiome of soil and water. Bacteria exposed to these antibiotics may gain resistance to the antibiotics. This can be a major public health concern, because even the antibiotic resistant bacteria are harmless they may spread the resistance genes to pathogens. This, in turn, could impact human and animal health, as the antibiotics which we rely upon to treat infection will no longer be effective on treating resistant pathogens.

Manure Storage
Prior to land application, manure is usually stored in livestock waste management structures. In one study, the effects of anaerobic storage of manure on the fate of antibiotics and antibiotic resistance genes in manure were investigated. In this study, the levels of chlortetracycline and tylosin in manure slurry were monitored. The two antibiotics in swine manure degraded substantially over time under the anaerobic condition. The antibiotic resistance genes corresponding to chlortetracycline was also reduced substantially during manure storage. In contrast, the resistance genes corresponding to tylosin did not decrease significantly.
Application Method
Manure and manure slurry may be applied to fields using application methods such as broadcast, injection, and incorporation. These land application methods have varying effects on the spread of antibiotics and antibiotic resistance genes in croplands. A study was conducted to investigate how these land application methods may affect the concentrations of antibiotics and antibiotic resistance genes in runoff and soil following the land application of swine slurry. Results show that land application methods had no statistically significant effect on the aqueous concentrations of antibiotics in the runoff. However, among the three land application methods tested, broadcast resulted in the highest total mass load of antibiotics in runoff from the three simulated rainfall events. Similarly, broadcast resulted in higher concentrations of antibiotic resistance genes in runoff than did injection and incorporation. In manure amended soils, the effects of land application on the concentration of antibiotics were compound specific. No clear trend was observed in the antibiotic resistance gene levels in soil.
Vegetative Barrier
Vegetative barriers are strips of densely growing perennial plants seeded downslope on cropland adjacent to surface water. Vegetative barriers can stabilize the soil in local areas and reduce dissolved and sediment bound compounds in runoff, such as nutrients and particulates. The barriers are often used as an erosion control measure and some states regulate the use of vegetative barriers next to bodies of water and in areas with high slopes. One study tested whether vegetative barriers are effective in reducing antibiotics and antibiotic resistance genes. Results show that stripes of switchgrass (panicum virgatum L.) can effectively reduce antibiotic tylosin and its corresponding resistance gene erm(B) in runoff. Hence, vegetative barriers can be used as a low-cost option to reduce the spread of antibiotic and antibiotic resistance gene through runoff.
Conclusions
The control of manure-borne antibiotics and antibiotic resistance genes in the environment is complicated. Different antibiotic compounds have different properties, such as vulnerability to photo degradation and tendency to adsorb to soil particles. Hence, it is hard to use one land application strategy to effectively manage multiple antibiotics in both runoff and soil. Hence, knowing the dominant antibiotic compounds in the manure can be important. Similarly, different antibiotic resistance genes may be hosted in different bacterial species. These bacteria differ in their metabolisms and consequently respond differently to various land application strategies. Like the case for antibiotics, it is difficult to develop one land application strategy that would be effective to all classes of antibiotic resistance genes in manure. So, in addition to land application strategies, attention should also be given to develop manure storage strategies to reduce antibiotics and antibiotic resistance genes prior to land application.
For more information about this article, contact Xu Li.
Cataloging and Evaluating Dairy Manure Treatment Technologies
Proceedings Home | W2W Home 
Purpose
To provide a forum for the introduction and evaluation of technologies that can treat dairy manure to the dairy farming community and the vendors that provide these technologies.
What Did We Do?
Newtrient has developed an on-line catalog of technologies that includes information on over 150 technologies and the companies that produce them as well as the Newtrient 9-Point scoring system and specific comments on each technology by the Newtrient Technology Advancement Team.
What Have We Learned?
Our interaction with both dairy farmers and technology vendors has taught us that there is a need for accurate information on the technologies that exist, where they are used, where are they effective and how they can help the modern dairy farm address serious issues in an economical and environmentally sustainable way.
Future Plans
Future plans include expansion of the catalog to include the impact of the technology types on key environmental areas and expansion to make the application of the technologies on-farm easier to conceptualize.
Corresponding author name, title, affiliation
Mark Stoermann & Newtrient Technology Advancement Team
Corresponding author email address
Other Authors
Garth Boyd, Context
Craig Frear, Regenis
Curt Gooch, Cornell University
Danna Kirk, Michigan State University
Mark Stoermann, Newtrient
Additional Information
Acknowledgements
All of the vendors and technology providers that have worked with us to make this effort a success need to be recognized for their sincere effort to help this to be a useful and informational resource.
The authors are solely responsible for the content of these proceedings. The technical information does not necessarily reflect the official position of the sponsoring agencies or institutions represented by planning committee members, and inclusion and distribution herein does not constitute an endorsement of views expressed by the same. Printed materials included herein are not refereed publications. Citations should appear as follows. EXAMPLE: Authors. 2017. Title of presentation. Waste to Worth: Spreading Science and Solutions. Cary, NC. April 18-21, 2017. URL of this page. Accessed on: today’s date.
Field Technology & Water Quality Outreach
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Purpose
In 2015, Washington State Department of Agriculture (WSDA) partnered with local and state agencies to help identify potential sources of fecal coliform bacteria that were impacting shellfish beds in northwest Washington. WSDA and Pollution Identification and Correction (PIC) program partners began collecting ambient, as well as rain-driven, source identification water samples. Large watersheds with multiple sub-basins, changing weather and field conditions, and recent nutrient applications, meant new sites were added almost daily. The increased sampling created an avalanche of new data. With this data, we needed to figure out how to share it in a way that was timely, clear and could motivate change.
Conveying complex water quality results to a broad audience can be challenging. Previously, water quality data would be shared with the public and partners through spreadsheets or graphs via email, meetings or quarterly updates. However, the data that was being shared was often too late or too overwhelming to link locations, weather or field conditions to water quality. Even though plenty of data was available, it was difficult for it to have meaningful context to the general public.
Ease of access to results can help inform landowners of hot spots near their home, it can link recent weather and their own land management practices with water quality, as well as inform and influence decision-making.
What Did We Do?
Using basic GIS tools we created an interactive map, to share recent water quality results. The map is available on smartphones, tablets and personal computers, displaying near-real-time results from multiple agencies. Viewers can access the map 24 hours a day, 7 days a week.
We have noticed increased engagement from our dairy producers, with many checking the results map regularly for updates. The map is symbolized with graduated stop light symbology, with poor water quality shown in red and good in green. If they see a red dot or “hot spot” in their neighborhood they may stop us on the street, send an email, or call with ideas or observations of what they believe may have influenced water quality. It has opened the door to conversations and partnerships in identifying and correcting possible influences from their farm.
The map also contains historic results data for each site, which can show changes in water quality. It allows the viewer to evaluate if the results are the norm or an anomaly. “Are high results after a rainfall event or when my animals are on that pasture?”
The online map has also increased engagement with our Canadian neighbors to the north. By collecting samples at the US/Canadian border we have been able to map streams where elevated bacteria levels come across the border. This has created an opportunity to partner with our Canadian counterparts to continue to identify and correct sources.
What Have We Learned?
You do not need to be a GIS professional to create an app like this for your organization. Learning the system and fine-tuning the web application can take some time, but it is well worth the investment. GIS skills derived from this project have proven invaluable as the app transfers to other areas of non-point work. The web application has created great efficiencies in collaboration, allowing field staff to quickly evaluate water quality trends in order to spend their time where it is most needed. The application has also provided transparency to the public regarding our field work, demonstrating why we are sampling particular areas.
From producer surveys, we have learned that viewers prefer a one-stop portal for information. Viewers are less concerned about what agency collected the data as they are interested in what the data says. This includes recent, as well as historical water quality data, field observations; such as wildlife or livestock presence or other potential sources. Also, a brief weekly overview of conditions, observations and/or trends has been requested to provide additional context.
Future Plans
The ease and efficiency of the mobile mapping and data sharing has opened the door to other collaborative projects. Currently we are developing a “Nutrient Tracker” application that allows all PIC partners to easily update a map from the field. The map allows the user to log recent field applications of manure. Using polygons to draw the area on the field, staff can note the date nutrients were identified, type of application, proximity to surface water, if it was a low-, medium- or high-risk application, if follow-up is warranted, and what agency would be the lead contact. This is a helpful tool in learning how producers utilize nutrients, to refer properties of concern to the appropriate agency, and to evaluate recent water quality results against known applications.
Developing another outreach tool, WSDA is collecting 5 years of fall soil nitrate tests from all dairy fields in Washington State. The goal is to create a visual representation of soil data, to demonstrate to producers how nitrate levels on fields have changed from year to year, and to easily identify areas that need to be re-evaluated when making nutrient application decisions.
As part of a collaborative Pollution Identification and Correction (PIC) group, we would like to create a “Story Map” that details the current situation, why it is a concern, explain potential sources and what steps can be taken at an individual level to make a difference. A map that visually demonstrates where the watersheds are and how local neighborhoods really do connect to people 7 miles downstream. An interactive map that not only shows sampling locations, but allows the viewer to drill down deeper for more information about the focus areas, such as pop-ups that explain what fecal coliform bacteria are and what factors can increase bacteria levels. We envision a multi-layer map that includes 24-hour rainfall, river rise, and shellfish bed closures. This interactive map will also share success stories as well as on-going efforts.
Author
Kerri Love, Dairy Nutrient Inspector, Dairy Nutrient Management Program, Washington State Department of Agriculture
Additional Information
Results Map Link: http://arcg.is/1Q9tF48
Washington Shellfish Initiative: http://www.governor.wa.gov/issues/issues/energy-environment/shellfish
Mobile Mapping Technology presentation by Michael Isensee, 2016 National CAFO Roundtable
Sharing the Data: Interactive Maps Provide Rapid Feedback on Recent Water Quality and Incite Change by Educating the Public, Kyrre Flege, Washington State Department of Agriculture and Jessica Kirkpatrick, Washington State Department of Ecology, 2016 National Non-Point Source Monitoring Workshop
Whatcom County PIC Program: http://www.whatcomcounty.us/1072/Water-Quality
Skagit County, Clean Samish Initiative: https://www.skagitcounty.net/Departments/PublicWorksCleanWater/cleansamish.htm
Lower Stillguamish PIC Program: http://snohomishcountywa.gov/3344/Lower-Stilly-PIC-Program
GIS Web Applications: http://doc.arcgis.com/en/web-appbuilder/
Acknowledgements
The web application was a collaborative project developed by Kyrre Flege, Washington State Department of Agriculture and Jessica Kirkpatrick, Washington State Department of Ecology.
The authors are solely responsible for the content of these proceedings. The technical information does not necessarily reflect the official position of the sponsoring agencies or institutions represented by planning committee members, and inclusion and distribution herein does not constitute an endorsement of views expressed by the same. Printed materials included herein are not refereed publications. Citations should appear as follows. EXAMPLE: Authors. 2017. Title of presentation. Waste to Worth: Spreading Science and Solutions. Cary, NC. April 18-21, 2017. URL of this page. Accessed on: today’s date.
Manure Management Technology Selection Guidance
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Purpose
Manure is an inevitable by-product of livestock production. Traditionally, manure has been land applied for the nutrient value in crop production and improved soil quality.With livestock operations getting larger and, in many cases, concentrating in certain areas of the country, it is becoming more difficult to balance manure applications to plant uptake needs. In many places, this imbalance has led to over-application of nutrients with increased potential for surface water, ground water and air quality impairments. No two livestock operations are identical and manure management technologies are generally quite expensive, so it is important to choose the right technology for a specific livestock operation. Information is provided to assist planners and landowners in selecting the right technology to appropriately address the associated manure management concerns.
What did we do?
As with developing a good conservation plan, knowledge of manure management technologies can help landowners and operators best address resource concerns related to animal manure management. There are so many things to consider when looking at selecting various manure treatment technologies to make sure that it will function properly within an operation. From a technology standpoint, users must understand the different applications related to physical, chemical, and biological unit processes which can greatly assist an operator in choosing the most appropriate technology. By having a good understanding of the advantages and disadvantages of these technologies, better decisions can be made to address the manure-related resource concerns and help landowners:
• Install conservation practices to address and avoid soil erosion, water and air quality issues.
• In the use of innovative technologies that will reduce excess manure volume and nutrients and provide value-added products.
• In the use of cover crops and rotational cropping systems to uptake nutrients at a rate more closely related to those from applied animal manures.
• In the use of local manure to provide nutrients for locally grown crops and, when possible, discourage the importation of externally produced feed products.
• When excess manure can no longer be applied to local land, to select options that make feasible the transport of manure nutrients to regions where nutrients are needed.
• Better understand the benefits and limitations of the various manure management technologies.
Complete-Mix Anaerobic Digester – option to reduce odors and pathogens; potential energy production
Gasification (pyrolysis) system – for reduced odors; pathogen destruction; volume reduction; potential energy production.
Windrow composting – reduce pathogens; volume reduction
Centrifuge separation system – multiple material streams; potential nutrient
partitioning.
What have we learned?
• There are several options for addressing manure distribution and application management issues. There is no silver bullet.
• Each livestock operation will need to be evaluated separately, because there is no single alternative which will address all manure management issues and concerns.
• Option selections are dependent on a number of factors such as: landowner objectives, manure consistency, land availability, nutrient loads, and available markets.
• Several alternatives may need to be combined to meet the desired outcome.
• Soil erosion, water and air quality concerns also need to be addressed when dealing with manure management issues.
• Most options require significant financial investment.
Future Plans
Work with technology providers and others to further evaluate technologies and update information as necessary. Incorporate findings into NRCS handbooks and fact sheets for use by staff and landowners in selecting the best technology for particular livestock operations.
Corresponding author, title, and affiliation
Jeffrey P. Porter, P.E.; National Animal Manure and Nutrient Management Team Leader USDA-Natural Resources Conservation Service
Corresponding author email
Other authors
Darren Hickman, P.E., National Geospatial Center of Excellence Director USDA-Natural Resources Conservation Service; John Davis, National Nutrient Management Specialist USDA-Natural Resources Conservation Service, retired
Additional information
References
USDA-NRCS Handbooks – Title 210, Part 651 – Agricultural Waste Management Field Handbook
USDA-NRCS Handbooks – Title 210, Part 637 – Environmental Engineering, Chapter 4 – Solid-liquid Separation Alternatives for Manure Handling and Treatment (soon to be published)
Webinars
Evaluation of Manure Management Systems – http://www.conservationwebinars.net/webinars/evaluation-of-manure-management-systems/?searchterm=animal waste
Use of Solid-Liquid Separation Alternatives for Manure Handling and Treatment – http://www.conservationwebinars.net/webinars/use-of-solid-liquid-separation-alternatives-for-manure-handling-and-treatment/?searchterm=animal waste
The authors are solely responsible for the content of these proceedings. The technical information does not necessarily reflect the official position of the sponsoring agencies or institutions represented by planning committee members, and inclusion and distribution herein does not constitute an endorsement of views expressed by the same. Printed materials included herein are not refereed publications. Citations should appear as follows. EXAMPLE: Authors. 2017. Title of presentation. Waste to Worth: Spreading Science and Solutions. Cary, NC. April 18-21, 2017. URL of this page. Accessed on: today’s date.