California Ag Network

Category: Livestock

  • California Dairy Industry Improves Environmental Impact

    Milk is big business in California. It’s the agricultural product that brings in more farm revenue than any other in the state. It employs about 190,000 workers, and involves 1.78 million cows. Indeed, dairy has been important to California’s economy for decades, and over time innovations in animal husbandry, feeding and in growing crops that dairy cows eat have led to substantial changes in greenhouse gas emissions. Recently, Ermias Kebreab and his colleagues at the University of California, Davis, calculated exactly how much these emissions have changed in the 50 years from 1964 to 2014. Although the total emissions from the state’s dairy industry increased over that period, the state also produced much more milk, and the industry has become more efficient in terms of its emissions.

    As well as milk being important to California, California’s milk production is important to the US. The dairy industry has a long history in the state. It’s thought that the state’s export of cheese, for example, began in the year 1800, when a Russian commander called Ivan Kuskow sent produce from Sonoma to Russian settlements in Alaska. In the 25 years from 1975 to 2000, the state’s dairy industry boomed. California went from producing 9.4% to 19.2% of total US milk production, and overtook Wisconsin to become the state that produced more than any other. These days, about 40% of California’s milk leaves the state as different kinds of processed milk product, such as cheese, milk powder, butter, and whey.

    Assessing the greenhouse gas (GHG) emissions of this activity requires a lot of data about all of the inputs and outputs of dairy farming. It also requires fairly complex modelling. The research team pulled together data to describe each aspect of four processes—feed production, enteric methane, manure storage, and farm management—as part of a life-cycle assessment (LCA). These kinds of assessments sometimes only consider carbon footprints, but Kebreab and his colleagues opted instead for a more comprehensive analysis that included water and land use. They also opted to run two different LCA models to see how different the results were for different sets of assumptions in the modelling. The first model used primary data from five Californian dairy farms. The second used off-the-shelf numbers from the California Department of Food and Agriculture. Everything was inputted in tremendous detail. For example, separate dietary data were used for calves, heifers, pregnant heifers, close-up heifers, and lactating and dry cows in 1964, and further categories were added for the 2014 analysis.

    Overall, the GHG emissions for 2014 on average ranged between 1.12 and 1.16 kg of CO2e/kg of energy-corrected milk, depending on the specifics of the diet modelled. Energy-corrected milk is a standardized way of measuring milk produced, adjusted so that the milks across all cows and farms have the same fat (here, 4%) and protein (3.3%) content. In 1964, the GHG emissions were 2.11 kg of CO2e/kg of energy-corrected milk, so the GHG emissions per bottle of milk have reduced substantially. There have been improvements across the board. Emissions from enteric methane and manure have been cut in the process of producing a unit of milk, as have water use and land requirements. California’s dairy industry has fairly low emissions compared with the same industry elsewhere in the US.

    However, not every aspect of dairy farming has improved to the same extent. The team’s models revealed that methane from manure made up about 41% of the industry’s GHG emissions in 2014, compared with just less than a quarter (24.5%) of its emissions in 1964. The root cause of this appears to be the way that manure is commonly managed in the state. It is often stored in “lagoons” as opposed to in solid form, which means that the methane conversion factor from manure is higher than it could be.

    Reductions in water use—an important matter in a state that is prone to droughts—have been achieved through more careful farming of crops that comprise animal feed, as well as through genetic improvements that have led to sturdier crops that do not need as much watering. There have also been increased yields in these crops over the years. In turn, the greater yields have meant that the amount of land required to grow enough food to feed a cow for a year has come down.

    This assessment points to important successes. Yet it should be considered alongside the fact that the state’s dairy industry grew dramatically during the period studied. The number of dairy cows in California has more than doubled. Many Californians would probably agree that an industry that grows this much has a responsibility to keep asking how it could strive to further reduce its environmental footprint. The value of this study is that it brings answers to this question that farmers can take note of, and that industry organizations, and potentially the government, could take action to support. — By Anna Petherick, University of Oxford & International Milk Genomics Consortium

  • Request for Research Proposals to Support and Enhance Honey Bee Health

    Scientific research provides us with the foundation of knowledge we rely on in order to understand honey bee health threats and address them.

    Project Apis m. and the National Honey Board are requesting research proposals to support and enhance honey bee health. Proposals will be accepted between September 1, 2020 and September 30, 2020. Please visit www.ProjectApism.org/rfps to view the full RFP. PAm and NHB supported research projects can be explored in detail at the Bee Health Collective.

    In June, 2016 Project Apis m. (PAm) and the National Honey Board (NHB) announced that PAm would begin administering the NHB Production Research funds. This collaboration has streamlined efforts to support the beekeeping industry, by connecting the NHB research funding opportunities with several other efforts coordinated by PAm. This collaboration allows opportunities to consider a broader spectrum of efforts linked to supporting the industry, to support collaborations and synergy, and harmonize and access deeper resources when necessary for projects that need larger time or money commitments. Merging efforts has also resulted in one less round of work for all of our hardworking bee researchers who write proposals, the scientific reviewers who read them, and selection committees and administrators who see these processes through.

    The National Honey Board (NHB) is an industry-funded agriculture promotion group that educates consumers about the benefits and uses of honey and honey products. NHB research, marketing and promotional programs are funded by an assessment on domestic and imported honey and are designed to increase awareness and usage of honey by consumers, the foodservice industry and food manufacturers. For more information please visit www.honey.com.

    Project Apis m. (PAm) is the go-to organization at the interface of honey bees and pollinated crops. Since 2006, we’ve infused over $8.5 million into honey bee research and $2.9 million into forage programs, resulting in better pollination and increased crop yields for growers, and lower losses and better honey production for beekeepers. We work closely with commercial beekeepers, growers, and top bee scientists in the USA and Canada to fund projects and direct strategic efforts focused on practical solutions. PAm funds studies, offers graduate scholarships to encourage careers in pursuit of science-based solutions to honey bee challenges, and has expanding efforts to put forage on the landscape where bees need it most. We are a 501(c)5 nonprofit organization governed by an eleven-member board of stakeholders representing major national and state industry organizations, and an additional seven-member Science Advisory Board. Learn more at www.ProjectApism.org.

  • California Incentives Spur Dairy Manure Methane Digester Developments

    State incentives designed to help California’s dairy industry reduce methane emissions have led to a spike in the number of manure digester developments underway on California dairies. According to a new report from CoBank’s Knowledge Exchange, the wave of digester developments on California dairy farms has spurred interest in the technology nationwide.

    “Dairy producers outside of California may be anticipating future environmental mandates in their own states,” said Tanner Ehmke, manager of CoBank’s Knowledge Exchange division. “But the possibility of financial incentives and energy market opportunities are what’s capturing attention.”

    California’s 1.4 million dairy cows are the largest source of methane in the state, which put dairies in the spotlight when, in 2017, the state moved to reduce greenhouse gases (GHG) by adopting rules for methane emissions. Manure methane digesters are the primary means to reduce dairy emissions and offer the added benefit of capturing and recycling methane as renewable natural gas for energy.

    As a state law prohibits California from regulating methane from cattle farms until at least 2024, it has used incentives to encourage dairies to develop digesters. To date, the state’s dairy digester development program has awarded more than $183 million in grants for 108 digester projects. California’s legislated goal for 2030 is to reduce dairy manure methane emissions by 40% below 2013 levels and is about half way to that goal.

    A key driver behind the growth of manure methane digesters has been consumers’ increasing concern about GHG emissions. They are putting that concern into action by demanding products have smaller carbon footprints, pressure that is being felt by state governments, retailers and dairy supply chains.

    In turn, California has implemented two measures beyond the grant program that are driving digester development: the Cap-and-Trade program and the Low Carbon Fuel Standard (LCFS). These programs are now the main sources of revenue for dairy digester projects.

    Under the Cap-and-Trade program, regulated entities in California pay a fee to the state for their GHG emissions. This revenue funds the incentives for non-regulated sectors, like agriculture, to voluntarily reduce emissions. The LCFS, an option that has generated revenue for dairy biogas, works similarly to Cap-and-Trade but is focused on transportation fuels. Fuel suppliers are required to reduce the carbon intensity of their fuels by blending low carbon fuels or purchasing credits from an entity with excess credits.

    The decision to install a digester is multifaceted. The cost to install a digester varies greatly depending on the dairy’s location, size, manure management and existing infrastructure. But digester companies report the average cost for a herd of 2,500 cows at $3 million, depending on the manure equipment already in place.

    Scale is a key component impacting digester costs. A minimum of 2,000 cows is the threshold in California, where the typical digester is a covered lagoon digester producing gas for pipeline injection. Generally, each additional 1,000 cows reduces the cost per cow of digester projects by 15-20%.

    The risk of policy change to the Cap-and-Trade program and the LCFS is low in California, but risk may be higher for projects outside of California trying to capitalize on credits.

    The full report, “Interest in California Dairy Manure Methane Digesters Follows the Money,” is available on cobank.com.

    About CoBank

    CoBank is a $152 billion cooperative bank serving vital industries across rural America. The bank provides loans, leases, export financing and other financial services to agribusinesses and rural power, water and communications providers in all 50 states. The bank also provides wholesale loans and other financial services to affiliated Farm Credit associations serving more than 70,000 farmers, ranchers and other rural borrowers in 23 states around the country.

    CoBank is a member of the Farm Credit System, a nationwide network of banks and retail lending associations chartered to support the borrowing needs of U.S. agriculture, rural infrastructure and rural communities. Headquartered outside Denver, Colorado, CoBank serves customers from regional banking centers across the U.S. and also maintains an international representative office in Singapore.

  • Is the Gut Biome a Heritable Trait in Angus Cattle?

    While it’s long been said “you are what you eat,” a team of animal scientists in the University of Tennessee Institute of Agriculture is taking an in-depth look at how what you are is influenced by your ability to eat, at least in cattle.

    Phillip Myer, an assistant professor and microbiologist in the Department of Animal Science, is leading a new study to determine how the rumen, the largest compartment of the cattle stomach, and the microbes that inhabit it affect the conversion of low-quality feedstuffs into usable energy for ruminants. Funded by the USDA National Institute of Food and Agriculture, the $500,000 study seeks to identify whether the genetics of a particular cow influences the rumen microbiome and whether that influence can be passed on to future generations. “The overarching hypothesis of this project,” says Myer, “is that host beef cattle genetics are associated with the variation of microbes in the rumen, producing an individualized rumen microbiota among animals.”

    Myer believes that if certain microbes are significant for feed efficiency, disease resistance, and other desirable production traits in cattle, then ruminal microbes represent the greatest opportunity to rapidly improve beef cattle nutrition and influence growth to help producers meet future global protein demands.

    Specifically, the three-year project seeks to determine the microbes and microbial interactions in the rumen of Angus cattle as well as the microbes’ relation to feed efficiency. The scientists—including Jonathan Beever, director of the UTIA Genomics Center for Advancement of Agriculture; Brynn Voy, also a professor in the UT Department of Animal Science; and Larry Kuehn and James Wells, both with the USDA U.S. Meat Animal Research Center—also seek to estimate the heritability of the rumen microbes and microbial features and to identify host genomic markers that ensure heritability.

    The goal is microbiome manipulation to enhance agricultural production. Says Myer, “This project will ultimately provide a means to increase food availability while lowering environmental impacts, develop more sustainable cow-calf production systems, and enhance Angus breeding programs.”

    The project will dramatically advance the field of beef production agriculture to sustainably meet the protein requirements of an ever-increasing global population.

    The award is one of 23 that NIFA announced last month that should lead to better management strategies for animal production systems, enhance production efficiency, and further develop high quality animal products for human use. Each of the grants is part of NIFA’s Agriculture and Food Research Initiative.

    Through its land-grant mission of research, teaching and extension, the University of Tennessee Institute of Agriculture touches lives and provides Real. Life. Solutions. utia.tennessee.edu.

  • First Meal is Vital for Calf Survival

    The first meal of their lives may well determine the fate of calves; if they don’t get what they need quickly, the newborns may not survive to weaning age, said two scientists with the Agricultural Research Service (ARS).

    Colostrum is a vital nutrient that mothers provide in the first feedings that newborn farm animals must have within 24 hours of birth. Calves are born without much of an immune system, and colostrum provides them with a rich dose of antibodies, or immunoglobulins.

    “It is very important for a calf to receive protective antibodies from its mother,” said Mike Clawson, research molecular biologist at the ARS Genetics, Breeding, and Animal Health Research Unit in Clay Center, NE.  “Those antibodies can protect the calf from the same pathogens its mother was exposed to long enough for its own immunity to develop.” Clawson’s research includes the genomic aspects regarding the failure of passive transfer of colostrum antibodies in cattle.

    A Hereford cow nurses her calf. Calves that do not receive enough colostrum face increased risk of disease and death (Photo by Bruce Fritz).

    Calves that do not receive antibodies from their mothers are at profound risk for disease and death. Before they are born, their mothers concentrate immunoglobulins in colostrum, which is essentially a first milk. Calves typically nurse shortly after birth, and the ingested antibodies are ultimately transported to their circulatory system.

    Timing is everything in this process because shortly after delivery, the mother’s production of immunoglobulin drops by 90 percent. In roughly that same time span, newborns lose the ability to take in the benefits of colostrum.

    “The newborn gut is permeable to large molecules at birth, but within 24 to 48 hours it becomes impermeable to them,” said Jeff Vallet, ARS national program leader for food animal production in Beltsville, MD. “Even if we were to provide colostrum to older newborns, absorption of the immunoglobulins is reduced or eliminated.”

    According to Clawson, colostrum deprivation is the greatest risk factor for a calf to become sick or die before weaning. “Calves that do not receive colostrum are 50 times or more likely to die in the first 3 weeks of life,” he said. Calves that do not receive adequate colostrum yet manage to survive past weaning are at elevated risk for developing disease later in their lives.

    Farmers, ranchers and veterinarians can determine the colostrum status of their newborn livestock through the simple immunocrit blood test. If the newborns lack immunoglobulins, they may be hand-fed commercially available colostrum replacements or supplements.

    A 2016 paper published in Europe studied the cost of colostrum antibody deficiency to calves. That study estimated a loss of about $68 and $91, respectively, for each dairy and beef calf. In the United States, over 20 percent of beef cattle calves and 19 percent of dairy calves suffer from colostrum deprivation. – by Scott Elliott, USDA-ARS Office of Communications

  • USDA Announces Changes to Emergency Haying & Grazing Provisions

    The U.S. Department of Agriculture’s (USDA) Farm Service Agency (FSA) today announced changes for emergency haying and grazing of acres enrolled in the Conservation Reserve Program (CRP). This includes changes outlined in the 2018 Farm Bill that streamlines the authorization process for farmers and ranchers.

    “FSA authorizes emergency haying and grazing of Conservation Reserve Program acres under certain conditions to provide emergency relief to livestock producers in times of severe drought or similar natural disasters,” said FSA Administrator Richard Fordyce. “These program changes will simplify the authorization process with an automatic trigger by severe drought designation, allowing livestock producers to quickly access much-needed forage.”

    Program Changes

    Previously emergency haying and grazing requests originated with FSA at the county level and required state and national level approval. Now approval will be based on drought severity as determined by the U.S. Drought Monitor.

    To date, 500 counties nationwide have triggered eligibility for emergency haying and grazing on CRP acres. A list by state and map of eligible counties are updated weekly and available on FSA’s website.

    Producers located in a county that is designated as severe drought (D2) or greater on or after the last day of the primary nesting season are eligible for emergency haying and grazing on all eligible acres. Additionally, producers located in counties that were in a severe drought (D2) status any single week during the last eight weeks of the primary nesting season may also be eligible for emergency haying and grazing unless the FSA County Committee determines that forage conditions no longer warrant emergency haying and grazing.

    Counties that trigger for Livestock Forage Disaster Program (LFP) payments based on the U.S. Drought Monitor may hay only certain practices on less than 50% of eligible contract acres. Producers should contact their local FSA county office for eligible CRP practices.

    Counties that don’t meet the drought monitor qualifications but have a 40% loss of forage production may also be eligible for emergency haying and grazing outside of the primary nesting season.

    CRP Emergency Haying and Grazing Provisions

    Before haying or grazing eligible acres, producers must submit a request for CRP emergency haying or grazing to FSA and obtain a modified conservation plan from the Natural Resources Conservation Service (NRCS).

    Emergency grazing is authorized for up to 90 days and emergency haying is authorized for up to 60 days. Program participants must stop haying and grazing 30 days before the first freeze date in the fall based on the dates established for LFP.

    Under the emergency grazing provisions, producers can use the CRP acreage for their own livestock or may grant another livestock producer use of the CRP acreage. The eligible CRP acreage is limited to acres located within the approved county.

    For emergency haying, producers are limited to one cutting and are permitted to sell the hay. Participants must remove all hay from CRP acreage within 15 days after baling and remove all livestock from CRP acreage no later than 1 day after the end of the emergency grazing period. There will be no CRP annual rental payment reduction for emergency haying and grazing authorizations.

    More Information

    For more information on CRP emergency haying and grazing visit fsa.usda.gov/crp or contact your FSA county office. To locate your FSA office, visit farmers.gov/service-locator. For more disaster recovery assistance programs, visit farmers.gov/recover.

    All USDA Service Centers are open for business, including some that are open to visitors to conduct business in person by appointment only. All Service Center visitors wishing to conduct business with the FSA, Natural Resources Conservation Service or any other Service Center agency should call ahead and schedule an appointment. Service Centers that are open for appointments will pre-screen visitors based on health concerns or recent travel, and visitors must adhere to social distancing guidelines. Visitors may also be required to wear a face covering during their appointment. Field work will continue with appropriate social distancing. Our program delivery staff will be in the office, and they will be working with our producers in office, by phone and using online tools. More information can be found at farmers.gov/coronavirus.

  • FARM Program Recognized Again for International Quality Certification

    The U.S. Department of Agriculture (USDA) Agricultural Marketing Service once again approved the National Dairy Farmers Assuring Responsible Management (FARM) Animal Care Program’s animal welfare standards, determining that the program’s 4th version meets the requirements of the International Organization for Standardization (ISO) Technical Specification. FARM was the first animal-care program in the world to have its updated standards verified through this process.

    “The ISO certification for the FARM Program demonstrates its importance and validates our industry’s commitment to animal care not only domestically but also in the world market,” said Jim Mulhern, president and CEO of the National Milk Producers Federation, which administers the FARM program.

    The assessment to the ISO standard determines whether animal welfare programs meet international standards for animal care as set by an independent standards-setting organization. FARM was evaluated to ensure that the standards in Version 4.0 of its Animal Care program meet the highest quality in species-specific welfare practices.

    Jim Mulhern, president and CEO of the National Milk Producers Federation

    The World Organization for Animal Health (OIE) and ISO work together to help farmers and programs like FARM standardize and implement their animal care guidelines. The OIE, the World Trade Organization-recognized body for setting animal health and welfare standards affecting international trade, adopted dairy cattle welfare standards in 2015.

    FARM was the first livestock program in the world recognized for the technical specification in 2018. It repeated the USDA verification process to provide an additional level of assurance for the improvements made to the program in its fourth iteration. The verification by USDA signifies to FARM Program participants that its standards are among the best in the world; it also signals to consumers they can have confidence their dairy products were produced in accordance with the highest level of science-based animal care.

    The National Milk Producers Federation (NMPF), based in Arlington, VA, develops and carries out policies that advance dairy producers and the cooperatives they own. NMPF’s member cooperatives produce the majority of U.S. milk, making NMPF the voice of dairy producers on Capitol Hill and with government agencies. Created by the National Milk Producers Federation in partnership with Dairy Management Inc, the National Dairy FARM (Farmers Assuring Responsible Management) works with all U.S. dairy farmers, co-ops and processors, to demonstrate to dairy customers and consumers that the dairy industry is taking the very best care of cows and the environment, producing safe, wholesome milk and adhering to the highest standards of workforce development.

  • Getting the Facts Straight About Dairy’s Global Carbon Footprint

    The following article was written in response to a recent report released by the Institute for Agriculture & Trade Policy — The dairy sector is committed to producing nutritious foods in environmentally sound and responsible ways.  As such, we welcome any opportunity to further the dialogue about solutions to climate change and creating a sustainable future for everyone. However, this report, while interesting, contains several inaccuracies and as such does not reflect the reality of the dairy sector.

    Environmental Impact

    Globally, all of agriculture accounts for 24% of greenhouse gas (GHG) emissions, and within that dairy is responsible for 2.7%.  While the dairy sector is committed to sustainable development and decreasing our rate of emissions even further, this 2.7%  emissions rate must be put into the context of emissions from other sectors, such as energy – 25%, business – 21% and transport – 14%. Especially when considering the positive impact dairy has on livelihoods and nutrition.

    One of the key claims in this report is that the top 13 global dairy companies saw an 11% increase in GHG emissions between 2015 and 2017. This is misleading, as much of the increase can be accounted for by mergers and acquisitions by those companies. Annex 1 in the report even confirms this is simply an accounting change, and these are not new emissions.

    The United Nations (UN) Food and Agriculture Organization’s (FAO) 2019 report, “Climate Change and the Global Dairy Sector,” was referenced. Key information about that report was left out, including the fact that it was multi-stakeholder study written by FAO. FAO found that between 2005-2015, milk production increased 30% globally in order to meet growing consumer demand. Absolute emissions rose 18% and emissions per unit of product declined by 11%. Without improvements made by the sector, FAO noted that total emissions from dairy would have increased by nearly 38% globally over this period to deliver the same amount of product.

    The global dairy sector takes its environmental responsibilities seriously and has a number of programs in place including the Declaration of Rotterdam and the Dairy Sustainability Framework  to support increased knowledge, implementation of practices and progress measurement against  sustainability challenges.

    Sustainability

    In using terms like sustainability, a clear definition is essential. The UN determines sustainability must be based on three pillars: economic, social and environmental.

    The dairy sector helps to feed the world delivering vital nutrition in the form of high-quality protein and essential vitamins and minerals. Globally, dairy provides 5% of energy, 10% of protein and 9% of fat in the diet, as well as providing vital nutrients like calcium, iodine, B vitamins, zinc and phosphorus.

    This rich nutrition helps populations, particularly in developing nations, avoid malnutrition and poor health outcomes. Any food system which fails to deliver high-quality nutrition is one which is itself, unsustainable.

    Dairy provides for the livelihoods of 1 billion people worldwide: 600 million people living on dairy farms and a further 400 million relying on the full-time jobs created in support of the sector. There are 133 million dairy farms around the world, and 37 million of them are led by women. A sustainable dairy industry must also be one which provides a livelihood to farmers, processors and all others along the supply chain. If farmers were always paid below the cost of production as implied in this report, put simply – the industry would not exist, and production would not be increasing.

    Dairy Economics 

    Globally, the dairy sector is incredibly diverse, with only 0.3% of all farms having more than 100 cows. In fact, the average herd size for a dairy farm is 3 cows. It’s also important to note that the majority of milk globally is processed through co-operatives, which are owned by and run in the interests of farmers.

    A one-size-fits-all farming system cannot be implemented worldwide. Each type of farming system has its place and irrespective of size, if managed well can be efficient and drive sustainability. It cannot be assumed that smaller scale farming is more efficient and is somehow better at delivering sustainability improvements or economic returns. There is no correlation between scale of production unit, either at the farm or processor level, and environmental impact assessed per unit of production. This is determined by the quality of the equipment used and the management.

    Larger businesses achieve economies of scale in many ways including on GHG emissions, as there is greater use of technology.

    This report seems to argue against international trade in dairy products. However, international trade ensures consumers in countries that are not self-sufficient can access the nutrition they need. The alternative would be either higher food prices or lower nutrient intake.

    The dumping of milk in response to COVID-19 in some regions was a temporary phenomenon in response to extraordinary market disruption caused by the pandemic, the likes of which the world has not seen in a century. This can’t be used to provide any valuable insight into how the industry should operate long term and does a disservice to the dairy sector which continued in extremely difficult circumstances to provide highly nutritious food for the global population.

    It’s very easy to put out a report that criticizes and tries to paint a simple picture of a sector which doesn’t contain all of the nuances or realities of how the global dairy sector nourishes the world with nutrient-rich, safe foods and does so in a manner that strives for continued environmental improvements while providing livelihoods to a large percentage of the world’s population. —Dr. Judith Bryans, President of the International Dairy Federation, and Donald Moore, Executive Director, Global Dairy Platform

  • Reusing Chicken Litter Shows Benefits

    Chicken is the most consumed protein in the United States. According to the National Chicken Council, the U.S. produced more than 9.2 billion broiler chickens in 2019. US consumers spent more than 95 billion dollars on chicken products.

    All these broilers – chickens raised for meat – need millions of tons of litter, or bedding material. Reusing chicken litter can save costs. There exists some health and safety concerns though.

    A new study shows that the environment in reused poultry litter can deter growth of pathogens like Salmonella.

    “When you read or hear that broiler litter is reused to raise multiple flocks of chickens, the typical reaction is that it must be bad for food safety,” says Adelumola Oladeinde, a co-author of the recent study. “Our study demonstrates the exact opposite.”

    Oladeinde is a researcher at the USDA’s National Poultry Research Center in Athens. He and his colleagues found that ‘good’ bacteria in used poultry litter can hinder Salmonella growth.

    “It may be worthwhile to invest time and resources to characterize the bacteria in reused litter,” says Oladeinde. “We can develop the promising ones into beneficial microbes for better chicken gut health.”

    The study also explored litter characteristics, such as moisture and ammonia levels. These characteristics can dramatically affect the litter microbiome – the mix of bacteria, fungi, and viruses in litter.

    “Our findings provide new information on the relationship between the physical environment of broiler litter and its microbiome,” says Oladeinde. “Management techniques that account for both factors may help reduce Salmonella in chickens.”

    Chicken litter plays a big role in determining broiler health. After a broiler chick gets to a farm, it usually spends the next several weeks pecking and living on litter.

    In fact, chicks begin to eat litter even before eating from feeding troughs or drinking. The microbiome present in the litter likely become the ‘first settlers’ in the guts of the chicks.

    “These first microbes play a key role in determining gut health,” says Oladeinde. “Therefore, it is critical to determine what a beneficial litter microbiome looks like.”

    The team collected samples of reused poultry litter from the University of Georgia Poultry Research Center. The litter was used to raise three flocks of broiler chickens under conditions like those used in broiler farms. “Each sample represents a unique broiler litter environment,” says Oladeinde.

    In the lab, researchers measured characteristics of the litter samples. Then they added Salmonella to each sample. After that, the samples were tested for levels of Salmonella, other bacteria, and physical characteristics.

    Within two weeks of adding Salmonella, most samples developed predictable microbiomes. Certain microbes, such as Nocardiopsis bacteria, seemed to reduce growth of Salmonella.

    That makes sense, according to Oladeinde. Some species of Nocardiopsis bacteria are known to produce antibiotics and toxins. These compounds could be keeping Salmonella levels low in the litter samples.

    A key aspect of reusing broiler litter is how long to wait before reuse. This waiting period is called litter downtime.

    “For farmers, a shorter downtime will result in growing more birds through the year,” says Oladeinde. However, we know little about how downtime affects litter microbiome.

    Results from the study show that surveying levels of specific bacteria could help determine if litters have had enough downtime. That could be of big help to farmers.

    “Poultry litter is a complex environment to study,” says Oladeinde. “We showed that the reused litter after two weeks of downtime had a microbiome that was unfavorable to Salmonella.”

    Oladeinde aims to repeat these experiments with litter from various sources. He also wants to test for multiple Salmonella strains. “These studies will tell us about the underlying mechanisms behind reusing litter and reducing Salmonella,” he says.

    Read more about this research in Journal of Environmental Quality. This work was funded by the United States Department of Agriculture, Agricultural Research Service.

  • Research Opp: Improving Our Understanding of Antibiotics in Dairy Farms

    Antibiotics play an essential role in maintaining animal health and productivity. To provide guidance and knowledge on antibiotic use and management practices, it is important to constantly update our understanding on the role of therapeutic antibiotic use and its impact on animal health. A veterinary project is being conducted by UC Davis to better understand antimicrobial resistance patterns in dairy calves, and we are looking for interested farms to participate in the study.

    The project will last around 1-2 months, with up to 2 people visiting the farm a few times a week to collect fecal samples and health data from animals. Any and all data generated will be made available to the owner/manager, and anyone entering the premises is willing to sign a waiver liability release if requested. Identity of participants will remain confidential. No photos will be taken on the facility without consent, and participants are free to back out of the study at any point, if they wish to do so.

    If interested and/or to obtain more information, please contact:
    Katie Lee (UCD, graduate student): lctlee@ucdavis.edu (408-239-9140) Rob Atwill (UCD, Professor): ratwill@ucdavis.edu (530-754-2154)