Methane from Manure Storage may be Greater than from Enteric Fermentation 

Climate change and greenhouse gas emissions receive a lot of attention in the media and with consumer-facing businesses. A lot of attention has focused on sources of greenhouse gases, especially related to fuel sources we use and food sources we eat. When it comes to food sources, ruminant animals, particularly cattle, receive a lot of attention for the large amount of methane produced. Methane is greenhouse gas with a global warming potential approximately 28 times greater than carbon dioxide, making it a relatively potent greenhouse gas, but not the most potent. 

Methane is produced during anaerobic (i.e., without oxygen) fermentation of organic material such as the digestion of feed in the rumen or degradation of manure in liquid storage facilities. Methane produced in the rumen of cattle and sheep has long been an area of study as it is a loss of energy from the feed that the animal does not get to use for growth, which is why it has been the target for development of interventions. Our understanding of this process is quite in depth and development of methods to reduce methane production in the rumen of cattle is an ongoing area of research. Many feed additives have been tested for their ability to reduce methane production and many are commercially available. 

Compared to other greenhouse gases such as carbon dioxide and nitrous oxide, methane is relatively short-lived in the atmosphere – approximately 12 years compared with 100+ years. From the standpoint of combating climate change, reduction in methane emissions could have the most immediate impact because of the short life of methane in the atmosphere. Thus, methane has become a focus for reducing overall greenhouse gas emissions. 

Methane is part of the biogenic carbon cycle where plants containing carbohydrates are consumed and digested by cattle, which produce and eructate, or belch, methane into the atmosphere. Methane in the atmosphere is converted to carbon dioxide over a 12-year period, and the carbon dioxide is assimilated by plants into carbohydrates. With a steady herd size, cows grazing pasture do not increase the amount of methane in the atmosphere, but when we increase the number of cows, then the amount of methane in the atmosphere increases. Vice versa, when we decrease the number of cows the amount of methane in the atmosphere decreases.  

The original method to compute global warming impact of greenhouse gas emissions did not account for the shorter life span of methane in the atmosphere and did not consider the trend in methane emissions with increasing or decrease herd size. A new method of calculation now accounts for the shorter life of methane in the atmosphere and the trend in herd size, which results in lower methane emissions overall (Figure 1). 

As mentioned above, methane is produced from manure. Storage of dry manure allows for aerobic (i.e., with oxygen) degradation of organic material such that little methane is produced. In contrast, storage of liquid manure creates an anaerobic degradation of organic material resulting in substantially more methane production. It does not matter whether the manure came from a ruminant animal or not as to the methane produced from manure – it primarily determined by the manure storage type. In current livestock production systems, beef cattle and poultry manure are stored primarily as dry manure, whereas dairy cattle and swine manure are stored primarily as liquid manure.  

Storage of manure in the dry form produces very little methane regardless of calculation method as can be seen with beef cattle and poultry in Figure 2. However, storage of manure in the liquid form produces a significant amount of methane as can be seen with dairy cattle and swine. The population of beef cattle decreased, and the population of dairy cattle was relatively constant from 2010 to 2020 resulting in the new method estimating lower enteric methane emissions than the old method (Figure 1). However, the amount of manure stored in liquid form has been increasing in dairy cattle operations resulting in increased manure methane emissions using the new compared with old method (Figures 1 and 2). 

Thus, of the total methane emissions from 2010 to 2020, enteric methane accounted for the most emissions at 75% using the old method, whereas manure methane accounted for the most emissions at 65% using the new method. With the new method likely the most accurate, addressing manure methane emissions may have the greatest immediate impact on total greenhouse gas emissions because a readily available and feasible technology in manure digesters already exists. The leading roadblock to implementation of this technology is cost, but public policy and consumer facing business could make substantial headway with financial incentives for dairies and swine operations to install manure digesters. 

Figure 1. Estimated cumulative emissions for enteric and manure methane production of the U.S. livestock industry from 2010 to 2020 using the old and new methods of calculation. MMT = million metric tons. Adapted from Beck et al. (2023;

Animal Welfare and Sustainability in Beef Production 

Animal welfare is a hot topic and the most frequent term used when consumers are asked to define sustainable beef. In many instances animal welfare can be associated with clear controversial issues such as swine gestation crates and poultry battery cages but those are not used in the beef industry, so you might think that the beef industry does not have any animal welfare issues or room for improvement. Even though less negative publicity is attribute to beef production compared to other livestock sectors, cattle welfare is still top of mind for consumers who buy beef products. So, what are the animal welfare issues in beef production and how can we address them?  

First, let’s learn how animal behavior and welfare scientists evaluate animal welfare. Many conceptual frameworks exist, but the most basic and well known involves the 5 freedoms (Figure 1) –  

  1. freedom from hunger and thirst,  
  1. freedom from discomfort,  
  1. freedom from pain, injury or disease,  
  1. freedom to express normal behavior, and  
  1. freedom from fear and distress.  

These are assessed using resource-based measurements such as availability of proper nutrition, protection from the elements, and natural environment in which to live, animal-based measures such as expression of normal behavior, availability of veterinary care, and incidence of injuries and disease, and management-based measures such as proper training of personnel in animal husbandry, low-stress animal handling procedures, and characteristics of transportation.  

Good animal welfare is important to sustainable beef production as it is directly associated with animal health and behavior, which can affect cattle performance and profitability. Some of the animal welfare concerns in the beef industry raised by animal welfare specialists comprehend the difficult or failure to identify and treat sick animals in large operations; procedures considered painful such as branding, castration, and dehorning; impacts of heat and cold stress on health; risk for digestive disorder in feedlot cattle; long transportation times, commingling, and feedlot overstocking. 

Research indicates that cattle with poor nutrition, subclinical disease, and stress have reduced growth and reproductive performance. It has long been known that relieving environmental stressors (cold, heat, mud, long transportation times, etc.) improves growth of cattle, and more recently we have learned that lessening psychological stressors such as human handling and weaning improves cattle performance. 

The U.S. Roundtable for Sustainable Beef’s definition of animal health and well-being aligns well with the 5 freedoms and is the cumulative effects of cattle health, nutrition, care, and comfort ( They indicate that 4 key considerations should be the focus of management decisions and ranch practices: 

  1. Provide adequate feed, water, housing, and care 
  1. Provide disease prevention protocols 
  1. Provide facilities for safe and humane movement and restraint 
  1. Provide personnel with proper training in handling and care 

Applying these principles to the cow-calf sector of the industry indicates that cows should have adequate forage available to meet nutritional requirements, and when necessary, protein, energy, and mineral supplements to alleviate deficiencies. Cutting corners on nutrition obviously has negative implications on animal well-being, but also generally reduces efficiency and profitability.  

Cattle housing should include open pastures, clean wintering areas, and dry places to lie down when conditions dictate. Keeping cattle comfortable improves welfare and performance. Cold, wet, muddy cattle are not comfortable, their maintenance energy requires are 50 to 100% greater, and performance (growth or lactation) is reduced.  

Adequate cattle care involves regular, frequent herd checks to promptly identify diseased or injured animals for immediate treatment. Every ranch should have a veterinary client patient relationship to develop and implement effective herd health programs. Standard health programs such as vaccinating calves at branding and weaning are not always appropriate to manage the health challenges on every ranch. Ranch managers should work with their veterinarian to identify the specific animal health issues for their ranch to best protect the herd from disease. 

Cattle handling facilities should be designed for easy cattle flow and safety of cattle and humans during the process. Handling facilities do not have to be expensive to meet animal welfare standards but should be designed based on normal animal behavior and allow cattle to be moved using flight zone principles rather than frequent prodding. And all personnel, even if they have previous cattle experience, should be trained, or reminded of proper cattle handling and husbandry practices on every ranch, no matter how large or small. 

Training ranch personnel can be time consuming – keeping up with new developments in cattle handling and husbandry and developing training materials. The beef industry already has an effective training and education program, Beef Quality Assurance (BQA), that will cover the basics for every ranch. This program, provided by the state cooperative extension service, can help managers stay abreast of new practices and provide basic training for new employees. Ranch managers should provide additional ranch-specific training and monitor that BQA guidelines are being followed. 

A focus on achieving good animal welfare will improve sustainability of beef in the eyes of the consumer, and will increase the efficiency and profitability for the rancher. 

Figure 1. The basic 5 freedoms of good animal welfare. 

Genetic Focus on Improving Beef Sustainability

Beef production system efficiency and sustainability are important aspects shaping the future of the beef industry. Genetic selection has long included traits on growth, carcass, and reproduction, but recently more focus has been placed on traits that impact efficiency and sustainability such as mature cow weight, maintenance energy, and methane emissions. The most efficient and sustainable suite of genetic traits is not necessarily the same for all production environments. These components result in a complex web to navigate improvement in efficiency and sustainability moving forward. Let’s break down each component and look at it from a systems perspective. 

The cow-calf sector has a disproportionate impact on system efficiency and sustainability due to the large amount of feed required to maintain a cow. Cow efficiency has been the topic of discussion for decades, and it is generally agreed that more moderate-sized cows will be more efficient because of less feed consumed per pound of calf-weaned, and more cows per acre increases ranch productivity. But small cows are not necessarily more efficient in all ranch environments, and calves from smaller cows are generally less efficient in the feedlot. The majority of the improvements in efficiency and sustainability made in the beef industry over the last 4 decades have been due to increased meat produced per calf (i.e. cow maintained). Thus, moderating cow size, although improving efficiency in the cow-calf sector, could result in reduced efficiency and sustainability for the beef production system. Matching the correct cow genetics with the production environment and utilizing genetic selection to develop maternal and terminal sire lines is more likely to result in optimized efficiency and sustainability in the entire beef production system. 

Beyond herd average, selecting individuals that improve efficiency and sustainability is key to moving forward. Recent analyses indicate that improving feed efficiency and reducing maintenance energy requirements could have a large impact on sustainability; however, our ability to measure these in grazing animals and on large scale is lacking. For the last two decades, feed efficiency has been measured in growing cattle and with the development of EPDs for feed intake and feed efficiency, genetic progress is being made. The problem is that feed efficiency in growing cattle fed moderate to high concentrate diets does not translate into feed efficiency in grazing mature cows. And, even though body size is an indicator of total feed required for maintenance, selecting cattle with lower maintenance requirements per pound of body weight is difficult and labor intensive. Moving forward genomic EPDs will be critical to identify efficient cows on a large scale from the few phenotypes that will be able to be measured. Selecting cows of any body size with lower maintenance per pound of body weight will result in less feed to maintain body condition in cows and more feed available for growth in pre- and postweaning calves, which will greatly increase the efficiency and sustainability of the entire beef production system. 

Recently, geneticists have begun to evaluate the heritability of methane emissions. Besides being a greenhouse gas, methane is a loss of energy during feed digestion resulting in lower feed efficiency. Methane emissions and feed intake and efficiency are strongly, but not perfectly, linked such that genetic selection for improved feed efficiency and reduced methane emissions could greatly increase efficiency and sustainability of beef production. As with reducing maintenance energy requirements, reducing methane emissions per pound of feed results in increased feed nutrients absorbed by the animal for maintenance and growth. As genetic traits for methane become available, it is not just about reducing greenhouse gas emissions and climate change, but also about improving efficiency and profitability of raising beef cows and calves. Developing selection indices with both feed efficiency and methane emissions would likely result in cattle that are even more efficient. 

Developing new genetic traits to reduce maintenance energy requirements, increase feed efficiency, and decrease methane emissions will move the industry toward a more sustainable future. With a focus on improved efficiency, genetic selection will improve environmental sustainability and ranch profitability.

The Role of Beef in Food Security

Beef cattle consume primarily human, non-edible material – forage and high fiber byproducts. These feedstuffs cannot or are poorly digested by monogastric animals of which humans are one. Thus, ruminant animals, of which cattle are dominant species, are necessary to convert these abundant carbohydrates into human edible food – beef. In addition to digestion of carbohydrates, ruminants also digest the protein, vitamins, and minerals in these feedstuffs. But cattle are fed some human edible grains, primarily corn.

The question that arises is whether beef is a net nutrient contributor to the human nutrient supply. When it comes to protein, ruminants not only digest the plant protein and convert it into a human edible form, they increase the biological value of the protein, which means that beef protein meets the amino acid needs of humans better than the original plant protein. Beef has a biological value for humans 2 to 3 times that of the feedstuffs consumed in the beef supply chain. Looking at individual sectors of the beef supply, the cow-calf and stocker sectors have the greatest conversion ratio of human edible protein consumed by the cattle to human edible protein produced in beef because these sectors of the supply chain feed very little grain. Corn is the largest contributor of human edible nutrients consumed in the beef supply chain, which is why the feedlot sector has a low conversion of human edible protein.

Besides protein, beef is also a good source of many vitamins and minerals such as iron, zinc, selenium, phosphorus, vitamin B6, vitamin B12, riboflavin, niacin, and choline. Typically, absorption of vitamins and mineral from beef is greater than plant foods in addition to beef having a greater concentration of nutrients. Iron, zinc, vitamin B6, riboflavin, and niacin are absorbed 1.5 to 3 times better from beef than plant foods. Additionally, vitamin B12 cannot be produced by plants or animals, only microorganisms, and thus animal foods are the only source of vitamin B12 in the human diet.

A recent analysis evaluated the net contribution of the beef supply for these nutrients to the human diet. The beef supply chain has a net positive contribution of iron, phosphorus, riboflavin, niacin, and choline to the human diet (Figure 1). A large portion of the positive contribution is from organ meats, of which the US population does not consume much, but other cultures readily consume. Organ meats are a significant part of beef exports and the value of a beef carcass. Thus, organ meats are not only important for economic sustainability of the beef industry, but also social sustainability through reducing food security.

Figure 1. The nutrient conversion ratio of human edible nutrients produced in beef to human edible nutrients consumed in the beef supply chain. Values greater than 1 (indicated by the red line) mean that the beef supply chain is a net contributor to the human nutrient supply.

Optimum Rangeland Management is Likely Different Depending Upon the Ecosystem

Rangelands provide many human benefits such as food production, income for rural families and communities, recreation, wildlife habitat, soil carbon sequestration, plant and animal biodiversity, and water filtration. Grazing is often assumed to negatively impact the natural ecosystem and that removal of grazing would result in more pristine rangelands. The largest driver of forage and animal productivity, and economic return is proper stocking rate, and rotational or deferred grazing do not enhance these responses. But, management intensive grazing practices allow forages to store reserves during times of abundant precipitation, increase water-holding capacity, provide wildlife habitat at critical times of rearing young, and create a shifting mosaic with both old and new growth vegetation all the while maintaining animal productivity and income for ranchers. Therefore, several management factors such as stocking rate, grazing management, and fire regime can impact the human benefits received from rangelands.

Optimum rangeland management practices may differ depending on the ecosystems, and a recent analysis evaluated the interaction of ecosystem and rangeland management system at sites across the Great Plains. A computer simulation model capable of simulating plant growth and soil processes in response to stocking rate, grazing management, and fire regime was used for this analysis. 

Increasing stocking rate resulted in increased soil erosion at Kansas and Wyoming sites, but not at Montana, South Dakota, and Nebraska sites. Additionally, timed rotational grazing increased soil erosion at Kansas sites. Annual burning of rangelands in the spring increased soil erosion at all sites except Nebraska due to less ground cover to protect the soil; however, the computer simulation was not designed to evaluate changes in the population of invasive plant species that might occur without spring burning. In contrast, timed rotational grazing decreased nitrogen losses from runoff, leaching, and volatization at all sites, but nitrogen loss was not affected by stocking rate or annual spring burning at any site. 

Soil carbon deposition among rangeland management practices was highly dependent upon site. Rotational grazing had no effect on soil carbon deposition at Kansas and South Dakota sites, increased soil carbon deposition at Wyoming site, and decreased soil carbon deposition at Montana and Nebraska sites. In general, soil carbon deposition decreased with increasing stocking rate, but was somewhat dependent upon grazing management and site. Annual spring burning drastically decreased soil carbon deposition at all sites due to the fact that the previous year’s forage residue was no longer available to enter the soil.The results of the analysis confirmed that ecosystem effects the response to rangeland management practices such that there is no one-size-fits-all management system. The optimum rangeland management system will need to be developed locally. Additionally, there will be tradeoffs that will need to be evaluated by each rancher to meet their sustainability goals.

Drought-Related Reasons to Wait on Spring Turnout

Some places of the eastern Great Plains have received some rain, and the drought monitor looks a little better, but much of the Great Plains and Intermountain West are still in moderate to severe drought and areas of extreme drought are increasing. Warmer temperatures and a little moisture have caused some pastures to begin greening up, but without additional rain plant growth will be limited.

Turning out on these pastures too early will have detrimental effects on plant growth. Cattle will graze off the leaf area limiting the ability of the plant to photosynthesize sugars, which will require the plant to pull sugars from the roots. Without rain to stimulate more leaf growth the plant will rely more heavily on nutrient reserves in the roots, possibly decreasing the root zone and capacity to pull the limited moisture from the soil. This stunting of plant growth and reduction of the root zone will have negative effects on forage production in future years.

So, what can you do? Keep cattle off the pasture as long as possible with the optimism of more rain. Continue to feed hay or find other feed resources that may let you economically extend the winter feeding period. In a previous newsletter we discussed limit feeding cows. The difficulty is that lactating cows have their greatest nutrient requirements during this time from calving to rebreeding. Thus, feed expenses will be greater than the last few months. In late gestation, hay with total digestible nutrients (TDN) of 57% and crude protein (CP) of 10% will meet the nutrient requirements of a 1300-lb cow (Figure 1). But in early lactation, the same cow producing 20 lb of peak milk will require TDN of 59.5% and CP of 10.5%. To make up this nutrient deficit will require 4.5 lb/day of a supplement that has TDN of 75% and CP of 20%.

As Dr. Larson, likes to say “There is something magical about green grass.”. As a nutritionist, I am not sure about the magic, but early spring grass has a nutrient profile that will promote fleshing of early lactation cows (Figure 1). Cows that are in a positive energy balance from calving to rebreeding typically return to estrus sooner and rebreed better. There will be tough decisions to make this spring, because neither spring turnout or continued hay and supplement feeding are likely to be without consequences.

Spring Rains Bring Green Grass and Deep Mud

It has been abnormally dry across much of the cattle feeding country with moderate to severe drought in many places. Dry weather has made for good cattle feeding conditions across cattle feeding country. Typically, March and April are two of the wettest months of the year, which will be a blessing to most of the central plains and western US bringing spring pasture. But these wet months can also be times of extreme mud in dry lot situations. Cattle feeders in the Corn Belt are more likely to have issues with deep mud that can negatively impact cattle performance. Mud depths of 4 to 8 inches can decrease feed intake up to 15% primarily because cattle make fewer trips to the feed bunk. Mud-coated hair also does not insulate cattle well thus more energy is required to maintain body temperature. All of this can decrease daily gain 10 to 20% and increase cost of gain 15 to 25%. Given the dry conditions, it likely that interventions could still be used to minimize the negative effects of mud in the coming months. Correcting pen drainage issues, especially around the feed apron and water trough, and rebuilding mounds would be two important strategies to minimize the negative effects of mud.

Figure 1. Anticipated percent change in feed intake, daily gain and cost of gain for feedlot cattle with 4 to 8 inches of mud.

Assessing the Sustainability of Beef Cattle Ranching

A recent paper synthesized ranch sustainability indicators from multiple assessments to develop an overall set of indicators. The indicators include environmental, ecological and socioeconomic aspects of sustainability. The environmental indicators include things like soil carbon and stability, plant productivity, water quality and retention and condition of riparian systems. These indicators are highly influenced by grazing management. Several forms of grazing management exist that can improve these indicators; most involve some form of rotation so that land is not overgrazed leading to bare soil and that plants have rest to recover and develop strong root systems.

The ecological indicators include plant, animal and bird diversity. Again, these indicators are influenced by grazing management, where a diversity of plant species, plant densities and plant heights provide habitat for a diversity of animal and bird species. Also, fire regime is important in controlling the diversity of plant species, again providing habitat for different animal and bird species.

Finally, the socioeconomic indicators include rancher connection with the community, rancher satisfaction, livestock and non-livestock income, forage utilization and capacity to experiment. Many facets of ranch management affect these indicators such as size of the ranching operation, rancher ability to participate in community organizations and geographic location of the ranch. These indicators are the least thought about aspects of ranch sustainability, but are some of the most important because most of all ranching is a livelihood and way of life for people that brings meaning to their lives.

Collectively, these indicators provide a well rounded means of assessing ranch sustainability and communicating all the important aspects of sustainability to the public; not just the environmental aspect.

Grazing of Herbivores including Cattle is Essential for Wildlife Success

Phillip Lancaster, PhD
BCI Nutritionist

Wildlife are important to overall ecosystem function, are asthethically pleasing on range and pasture landscape, and provide recreation. When parts of the ecosystem change so can wildlife populations, and human activities have greatly altered the natural ecosystem. However, grazing of cattle on rangelands is much the same it was with bison many years ago – the large herbivore functions as an ecosystem engineer to create a variety of plant structures needed by wildlife. A recent analysis of published studies from the Great Plains region by researchers in the Department of Horticulture and Natural Resources and the Beef Cattle Institute at Kansas State University found that grazing overwhelmingly had no effect or a positive effect on several wildlife communities. The one exception being herptile communities, but few studies evaluated herptiles and more research is needed. Generally, grazing had minimal negative effects although specific grazing practices were not evaluated. Many individual wildlife species responded to varying degrees to grazing such that heterogeneous grazing pressure across the landscape provides a diversity of plant communities and structures to satisfy the habitat requirements of many wildlife species. Grazing management practices that create a heterogenous landscape are likely to result in greater wildlife diversity.

Figure 1. Proportion of studies that found negative effect, no effect, or positive effect of cattle or bison grazing on avian, mammal, herptile, or arthropod populations.

Impact of Local Food Purchases Depends upon the Product

Phillip Lancaster, PhD
BCI Nutritionist

Buying local is often touted as being more sustainable, but any improvement in environmental or economic sustainability is highly dependent upon the food product and where you are located. Many food products do not grow well in certain parts of the country. For example, it would be difficult to grow oranges anywhere in the U.S. except southern Florida, Texas, and California. Many of our food production systems revolve around the differences in climate across the U.S. that are optimal for efficient production. In beef industry, cow-calf operations are found in all 50 states because the predominate feed in this sector, grass, grows in all 50 states. However, the growing and finishing operations are concentrated in about 10 states in the center of the U.S., because the majority of feed in this sector, grains and byproducts, grow best in this region of the country. Additionally, the climate in the center of the country is optimal for efficient cattle growth, and efficiency is important for environmental and economic sustainability. Growing and finishing cattle in other regions of the country result in greater environmental impact.

The product being purchased impacts the transportation costs and the carbon emissions from fuel. Estimates of fuel usage and carbon emissions for buying eggs from a local farm are 50 to 60 times greater than buying from a local grocery store. The fuel usage per dozen eggs is significantly increased when the farmer brings a few dozen eggs to the local farmers market each week or each individual consumer travels to the farm each week to buy 1 dozen eggs compared to a semitruck delivery of 23,400 dozen eggs to the grocery store. Contrast that with buying beef locally where the consumer travels once per year to purchase a whole carcass for their freezer. The impact of transportation is much less in the beef scenario than in the egg scenario because the consumer is purchasing so much more food product with each trip, emphasizing the importance of efficiency as pounds of food product per gallon of fuel used.

Another touted benefit of buying local is more money goes to the farmer, but again the impact depends upon the food product being purchased (Figure 1). Purchasing locally produced bread would significantly increase the food dollar going to the farmer, where as purchasing a gallon of milk locally will have less of an impact on the farmer’s share of the food dollar. The difference between the farm share for bread versus milk has to do with the amount of further processing from the raw commodity to the final product. Wheat requires a lot of further processing to produce bread, which results in lots of additional costs that must be accounted for in the price of bread, whereas milk requires little further processing and minimal additional costs. Thus, it is the costs of further processing that really drive the farm share, and so the farmer’s share of the food dollar depends upon how much of the further processing was performed by the farmer.

Figure 1. Retail price, farm value, and farm share for various retail food products in 2019. 

Cattle are Major Recyclers in the Human Food Supply Chain

Phillip Lancaster, PhD
BCI Nutritionist

Food waste accounts for greater than 40% of food production, and food waste disposed of in a landfill contributes to methane emissions. Solid waste in landfills, although not all food waste, accounts for 14% of U.S. greenhouse gas emissions, which is more than agriculture at 9%. Globally, food waste accounts for 6 to 8% of greenhouse gas emissions; about half of the 14% contributed by livestock. However, most food waste could be recycled for a higher purpose. According to the food recovery hierarchy, food waste uses in order from least to greatest benefit are landfill/incineration, composting, industrial uses, animal feed, and donate to food pantries. Thus, animal feed is the most beneficial use of food not fit for human consumption.

Food waste occurs at many places along the food supply chain – food not harvested, lost during handling/transporting, industrial processing and manufacturing, retail groceries and restaurants, and in the home. Unfortunately, food not harvested or lost during handling/transporting has little chance of being recycled. Food waste from industrial processing and manufacturing sector is already highly recycled with only 5% going to landfills, but 45% of food waste from the retail level and 97% from the consumer level are disposed of into landfills. Over all sectors, recycling into animal feed is the largest (57%) destination of food waste followed by disposal in landfills (28%). Recycling into animal feed reduces the amount disposed into landfills.

One major issue with the use of food waste as animal feed is the variation in nutrient content from batch to batch. The unique digestive system of ruminants allows them to effectively utilize these variable feedstuffs with lesser consequences in performance than monogastric animals. Additionally, ruminants can utilize the wide variety of food waste sources produced in the food supply chain. Even though all livestock sectors use food waste derived animal feed, cattle are a major user because of their unique digestive system and large quantity of feed consumed daily. Thus, cattle contribute significantly to the efficiency and sustainability of the food supply chain.

Figure 1. Estimated amount of U.S. food waste destined for different end points. Adapted from Business for Social Responsibility, 2014

Heat Stress and Considerations for Fair and Show Season

Bob L. Larson, DVM, PhD
Beef Cattle Institute
Kansas State University

Fair and show season is a fun time of year that provides a great opportunity to compare breeding strategies, to participate in friendly competition with other producers, and to participate in a family activity. However, heat stress is an important concern for cattle exhibited in the summer time. Planning ahead to assure that cattle have access to plenty of water, shade, and airflow is necessary to reduce the risk of heat stress.

Almost every summer, at least some portion of the U.S. suffers from a period of extreme heat and humidity that can cause problems for cattle. As we move into summer, it is important to be prepared to limit the negative effects of heat stress. Cattle are more susceptible to heat stress than humans and can start to have problems if the temperature-humidity index reaches 80 or higher. Factors other than temperature and humidity are also involved with heat stress. These factors include: high body condition, black hide color, rainfall, lack of wind, lack of night cooling, crowding together to avoid flies or for other reasons, and consumption of endophyte-infected fescue.

Rain and high humidity reduces the ability of cattle to use evaporation to get rid of body heat. Evaporation of sweat is one of the primary means that cattle have to cool themselves at temperatures over 70°F. Hot weather immediately following a rain is often associated with heat stress in cattle. In addition, if winds are calm or cattle congregate behind a windbreak or to fight off biting flies, their ability to be cooled is reduced. Night temperatures that remain above 70°F increase the danger of heat stress because needed night cooling does not occur. Cattle that are not used to hot weather are also a greater risk if weather changes rapidly or they are shipped from a cool environment to a much hotter environment.

Another factor that plays a role in heat stress is hide color, with black-hided cattle at greater risk than cattle with light-colored hides. Breed plays a role in that Bos indicus breeds (Brahman and others) handle heat better than do Bos taurus (European) breeds. Show cattle that are not acclimated to a particular climate or that are nearing finished weight are at higher risk of heat stress. Cattle that have eaten endophyte-infected fescue may have increased body temperature and be predisposed to heat stress. Even following removal from endophyte-infected fescue pastures, cattle may continue to experience severe health problems related to summer toxicosis for several weeks.

During periods of heat stress, it is important to have ample water available. When temperatures reach 80 degrees, cattle need two to three gallons of water per 100 pounds of body weight and they must have access to water throughout the day. If cattle must be handled during hot weather, work them from midnight to 8 AM after at least six hours of night cooling. Providing shade to cattle (including show cattle) has been shown to reduce heat stress and to increase feed intake. Shade reduces the heat gain resulting from direct sunlight even when air temperature is not reduced. In a pasture or drylot setting, cattle seek out the coolest spots during periods of heat stress and are unwilling to leave these areas. Shades should therefore be placed over feed and over areas where the producer

wants the cattle to spend time. Shades should have a north-south orientation to allow drying under the shades as the shaded area moves throughout the day.

Air movement is important to dissipate heat. Fans can provide much-needed air flow in a cattle show setting. In pasture settings, it may be necessary to remove or fence off windbreaks during the summer. For cattle confined in a lot, enhance airflow by providing mounds for cattle to stand on. Move cattle away from windbreaks and wind dead spots in the feedlot. Sprinklers can be also used to combat heat stress. In geographic areas where humidity can be high, a large water droplet is required to wet the skin; fine mists or fog systems are not recommended. Sprinklers reduce heat stress by increasing evaporative losses, by reducing ground temperature and reducing radiant heat gain, and by reducing dust. Sprinkling should be done occasionally throughout the day, otherwise high humidity may result and there may be little opportunity for evaporation.

Attending fairs and exhibitions is very enjoyable and has many benefits to the participants. However, do not forget the risks that are taken anytime cattle are placed in a new environment especially if heat stress is a concern.

Large Herbivores, Whether Bison or Cattle, are Integral Parts of Grassland Ecosystems

Grasslands and rangelands are an important ecosystem providing food, income for rural families and communities, recreation, wildlife habitat, soil carbon sequestration, plant and animal biodiversity, and water filtration. Thus, grasslands and rangelands contribute to all three pillars of sustainability: environmental, social, and economic. Grazing is often assumed to negatively impact the natural ecosystem and that removal of grazing would result in more pristine rangelands. To the contrary, grazing has had minimal effects on plant species richness over long periods of time, e.g., 13 to 65 years. Additionally, lack of grazing created grasslands with greater shrub cover dominated by fewer species. In contrast to plant species, continuous grazing in general has a negative impact on wildlife populations, because different wildlife species require different types of habitat varying widely from tall and dense to short and sparse.

Grassland and rangeland management practices influence the benefits received from these ecosystems. Heavy grazing decreases animal productivity and income for ranchers, increases soil erosion, decreases plant biodiversity which decreases wildlife habitat, and less forage production decreases soil carbon sequestration and water filtration. But, proper grazing management allows forages to store reserves during times of abundant precipitation, increase water-holding capacity, provide wildlife habitat at critical times of rearing young, and create a shifting mosaic with both old and new growth vegetation all the while maintaining animal productivity and income for ranchers. And patch burning regimes can be used to direct cattle grazing to specific sites within rangelands further producing numerous habitat structures for diverse wildlife species.

Prior to European settlement, rangelands were ‘managed’ by periodic fire and grazing by wild ungulates (bison, deer, and elk), which function as ecosystem engineers creating a diversity of plants and vegetation structures promoting wildlife habitat. Today, we have smaller areas of privately-owned rangelands interspersed with towns, cities, and cropland rather than wide open expanses for ungulates and fire to roam. And we generally use cattle rather than bison as the primary grazer. Some differences exist between cattle and bison in grazing behavior and how they utilize the landscape, but many of these differences are more a part of human management (fences, lack of predators, etc.) than inherent differences between bison and cattle. The many ecosystem services of grasslands and rangelands can be achieved by managing smaller privately-owned ranches using proper grazing management and fire regimes that promote all three pillars of sustainability.

Regenerative vs. Sustainable Agriculture: What is the difference?

By Phillip Lancaster

In the last 20 to 30 years, there has been a lot of discussion about sustainable agriculture. ‘Sustainable’ has been a buzzword in many industries for the last 20 years with everybody from farmers and ranchers to multi-billion-dollar corporations trying to find ways to be more sustainable. But what does the word sustainable really mean? If we break down the word, ‘sustain’ means to strengthen or support according to Oxford Dictionary. In the context of agriculture, we generally think of sustainability as the ability to support or maintain food production into the future, which suggests more efficient resource use. Agriculture has made tremendous strides in efficiency of resource use over the last 50 years.

Lately, the term regenerative agriculture has become a new buzz word, but it is really not a new concept. Robert Rodale coined the term ‘regenerative organic agriculture’ in the late 1970s as an approach that encouraged continuous innovation and improvement. Breaking down the word, regenerate means to regrow or replace what is lost. In the context of agriculture, we generally think of regenerative as replacing soil carbon/organic matter that was lost due to soil tillage or overgrazing. Again, agriculture has made tremendous strides in replacing soil carbon with adoption of no-till and cover cropping practices, and management intensive grazing in the last 30 years.

There are other aspects of the ecosystem such as plant and animal biodiversity that also fall under the idea of regenerative agriculture. Researchers are beginning to understand how grassland and rangeland management impacts plant species composition and wildlife populations, and developing novel management strategies to such as patch burning to enhance plant and animal biodiversity.

Many of the agricultural management practices that we considered sustainable are also regenerative. Whether the practice is sustainable or regenerative depends on the context of the situation in which the practice is being used. All soils have a maximum attainable soil organic carbon content based on physical characteristics (clay content, bulk density) and climate (rainfall, temperature). For example, a rancher whose soil has reached its maximum attainable soil organic carbon and practices management intensive grazing is sustaining the level of carbon. A second rancher whose soil has not reached its maximum attainable soil organic carbon and practices management intensive grazing is regenerating the level of carbon. Thus, even though they are using the same management practice, the first rancher is practicing sustainable agriculture whereas the second rancher is practicing regenerative agriculture.

As with soil organic carbon, a maximum attainable level of other aspects of the ecosystem will be achieved with regenerative agriculture.  At this point, we will move from replacing what was lost to maintaining the new level, and from regenerative agriculture to sustainable agriculture.

Intensification of Beef Production Aids in Sustainable Beef Production

Beef production is a significant contributor to global climate change. The source of greenhouse gas emissions is primarily due to inputs into the system such as fertilizer and feed. Estimates of greenhouse gas emissions from beef production are highly variable. Globally, livestock contribute 14% to 18% of total greenhouse gas emissions. Beef production alone accounts for a smaller percentage (6%). In the U.S., beef is an even smaller proportion – only 2%.

So why the discrepancy? Greenhouse gas emissions are highly dependent upon the production system. More intensive systems utilizing highly nutritious feeds, high quality animal genetics, and high levels of management such as the U.S. system produce more beef for each unit of input, which drives down the greenhouse gas intensity. The greenhouse gas intensity is the amount of greenhouse gas emissions per unit of output, in this case carcass weight.

Because of the investment in nutritional quality of feed, animal genetics and management practices, the U.S. system has the lowest greenhouse gas intensity of any major beef producing country (Figure 1). The U.S. produces 18% of the world’s beef and only 8% of the world’s greenhouse gas emissions from beef production. In comparison, Brazil produces 14% of the world’s beef and 19% of the world’s greenhouse gas emissions from beef production. The U.S. system has a ratio of 2.2:1 compared with Brazil’s ratio of 0.75:1 of contribution to beef production relative to contribution to beef greenhouse gas emissions. The U.S. production system has the highest ratio of any of the top 10 beef producing countries with Germany having the next closest at 2.0:1.

Comparisons among greenhouse gas emission intensities of countries (i.e., production systems) indicates that intensifying the system through improving efficiency should be the goal. A global effort to improve nutritional value of feed, increase cattle genetics for growth and yield, and increase producer education of optimum management practices will have the greatest benefit to sustainable beef production. If the other 9 of the top 10 beef producing countries developed beef production systems similar to the U.S., global greenhouse gas emissions from beef production would be reduced by 22%.  

Does beef production really use that much water?

Beef production often gets labeled as unsustainable partly because of its large water footprint. Estimates of the water used to produce one pound of beef are 1,675 gallons compared with 545 gallons to produce one pound of pork and 257 gallons to produce one pound of poultry. However, not all water has the same importance when it comes to sustainability. There are primarily 3 types of water used in the livestock production chain: green, blue and gray water. Green water is rainwater that landed on the field or pasture that required no human intervention to use. Blue water is primarily irrigation water for crops and drinking water for animals. Gray water is water used for cleaning animal facilities, processing plants, etc.

From a water sustainability perspective, blue and gray water are more important than green water because they involve removing water from its natural cycle, and blue and gray water could be used directly by humans. When we compare the water footprint of animal protein sources based on water type, it becomes clear that the important water footprint of beef is much more like poultry and pork (Figure 1). Over 90% of the water footprint for beef production is green water compared with 73% for pork and 79% for poultry. The blue and gray water footprint of beef is 158 gallons per pound compared with 146 gallons per pound for pork and 55 gallons per pound for poultry.

For all species of livestock, the vast majority (> 85%) of water use is to produce feed and the important type of water is blue water used to irrigate crops. Advances in irrigation technology and drought resistant crop varieties will further reduce blue water use for feed production. For example, subsurface drip irrigation can reduce irrigation water use by 45% and variable rate irrigation adjusts the amount of water applied to each square foot of the field based on soil characteristics and plant water needs. Also, in 2016, 40% of corn acreage in Nebraska and Kansas was planted to drought tolerant varieties.

When looking at the water types agriculture can control (blue and gray water), animal proteins are very similar in their water footprints. And technological advances in feed crop production will continue to reduce the blue water footprint of animal proteins.

Cows are not the primary cause of recent increase in methane

Atmospheric methane concentration has reached a record, but the exact reason has been difficult to determine. Atmospheric methane concentration increased 8 ppb per year during the 1980s, 6 ppb per year in the 1990s, then the trend was static from 2000 to 2007, but now increasing at 9 ppm per year since 2007 (Figure 1). The reason for the increased accumulation of methane in recent years is likely due to several factors. The methane budget includes both sources of emissions and sinks that remove methane from the atmosphere. The primary sources include agriculture, natural wetlands, fossil fuels, biomass burning, and other natural sources (oceans, lakes, termites). The primary sinks are chemical reactions in the atmosphere and soils. The increase in atmospheric methane concentrations means that emissions were larger than sinks, but which source has been the cause of the recent increase.

Ruminant animals account for the largest proportion of man-made methane emissions and cattle are by far the largest contributor. Estimated enteric methane emissions have increased since 2000, but the global cattle population has remained constant questioning the reason for the increased enteric methane emissions (Figure 1). Wetlands are the largest natural source of methane emissions and methane emissions from wetlands have also been increasing since 2000. Methane leakage during oil extraction is also a source of methane emissions into the atmosphere and was thought to possibly be the cause of increased methane due to the increase in shale oil extraction.

Based on the change in radio isotope ratio of atmospheric methane, the increase in methane emissions is likely from microbial sources which rules out fossil fuel extraction leaving enteric and wetland methane emissions. The largest increases in atmospheric methane coincide with the largest increases in global temperature. The largest methane growth rates (> 10 ppb) occurred in the tropics and subtropics through 2014 to 2017, which had average temperatures > 1°C warmer than the 1880-1909 baseline. Methane emissions from wetlands increase with increasing temperature because of increased microbial activity, but microbes in the rumen of cattle are at a constant 38°C such that global temperature would not be affecting microbial activity in the rumen. Additionally, the largest increases in methane emissions have come from the tropical and subtropical latitudes, where increased precipitation, flooding and temperature coincided between 2014 – 2017. Wetlands are the largest global source of methane emissions (Figure 2) and are a major driver of atmospheric methane especially with increasing global temperature.

Removal of methane through chemical reactions in the atmosphere can have a dramatic effect on methane lifetime. Hydroxyl, which is the chemical with which methane reacts in the atmosphere, concentrations in the atmosphere increased 10% between the late 1990s and mid-2000s coinciding with the plateau in methane concentrations from 2000 to 2007. But hydroxyl concentrations have decreased approximately 10% from mid-2000s to 2014 coinciding with the renewed increase in atmospheric methane concentrations.

The methane budget is not as simple as once thought and changes in relative amounts of sources and sinks can readily change the atmospheric concentration. Enteric emissions from ruminants is not always the primary driver and is not the largest emissions source. As global temperatures increase, wetland emissions may become a larger proportion of global methane emissions.

Figure 1. Global atmospheric methane (NOAA) and hydroxyl (Rigby et al., 2017) concentration, methane emissions from enteric fermentation (FAO) and wetlands (Zhang et al. 2017), and cattle population (USDA).
Figure 2. Contribution to global methane emissions by various sources. Adapted from the Environmental Change Institute, University of Oxford.

Food, Innovation, Service, & Hospitality Talk

The Association of Healthcare Food Service hosted their first ever Food, Innovation, Service, Hospitality (FISH) Talks – Live Panel at the 2019 national conference.   The broad subject of the panel was to provide healthcare leaders with information surrounding food and climate change that would help them purchase more sustainably.   The below clip shares improvements in ranching and farming over the decades thru the eyes of a dietitian, who was once in their food service shoes trying to make similar thoughtful choices.  

Thinking Beyond Food Waste to Food Recovery

As we listen to conversations about supply issues, food waste and providing food to the hungry, people not familiar with our beef commodity markets have asked why the U.S. exports beef as well as the ethics of feeding human edible beef to our pets. Here are some thoughts and facts to consider. You might think these concepts are common knowledge, and they probably are among your circle of agriculture friends. Sustainable food production questions rarely have simple answers, but try these to help us all have dialogue together and reach the common goal of a more sustainable food supply.

Why do we export beef to other countries?

The majority of beef variety meats are commonly exported as opposed to finding a home in the U.S.  Diets are cultural and ours does not typically include variety meats, but we respect that they are of value to others. In the U.S., they are mainly used as pet food ingredients.

Annual exports are generally 9 to 11 percent of total domestic beef production and are a critically important source of revenue.  U.S. beef producers receive about $300/head in additional premiums as a result of export values in fed cattle according to Oklahoma State University livestock economist, Derrell Peel.  Foreign markets are willing to pay much higher premiums for variety meats than the U.S. consumer and are also purchasing premium cuts as their economies improve.  

Why do we feed edible beef to our pets instead of feeding ourselves?

Twenty-five to 30% of the meat eaten in the U.S. is fed to dogs and cats, according to a recent UCLA study. There are 157+ million pets in the U.S. as of 2014 ,which is triple the number since the 1970’s.  

While it is not recommended that your dog and cat give up meat, it is good to know that the by-products from beef are an important nutritious ingredient as you do your research on the ingredient label. Veterinary nutritionists tell us that feeding by-products to pets not only is safe and healthy, but it is better for the environment and dramatically reduces food waste.  The pet food aisle has seen an influx of brands made with “human-grade” ingredients to lead us to believe they are better than those that contain animal by-products.  

The Environmental Protection Agency has developed the “Food Recovery Hierarchy” that demonstrates the most valuable use of food waste down to the last resort — the landfill. Wholesome, edible food should be kept in the human food supply whenever possible. When food is no longer edible for humans but still safe and wholesome for animals, the hierarchy recommends diverting these food scraps to feed animals, including pets.

Shifting gears, there is renewed interest in feeding food scraps to livestock as a way to reduce organic waste in landfills and the methane gas it generates.  After disease outbreaks were linked to animal feed back in the 1980’s, there are state laws that regulate the process of converting food waste to animal feed.  The Food and Drug Administration’s Bovine Spongiform Encephalopathy/Ruminant Feed Ban Rule also prohibits the use of animal tissue in feeds for ruminant animals such as cattle. Consumers are asking questions about how companies handle their waste, and more research and technology will be needed to overcome some of the barriers of re-feeding people leftovers to food animals. Cattle have demonstrated they can upcycle a variety of products into safe, quality food and can be a part of the environmental solution.   

Mitigating Ruminant Methane Emissions

Last month we evaluated data indicating that only 35% of current methane emissions from domestic ruminants is contributing to increased atmospheric methane. With reductions in methane emissions ranging from 10 to 50%, feed additives could almost eliminate the 35% contributing to atmospheric methane.  Many feed additives have potential adverse effects on the animal, but 3-nitrooxyproponal reduces methane emissions without negatively affecting animal performance and is in the process of commercialization. Furthermore, 3-nitrooxypropanol shifts rumen VFA profile toward higher proportions of propionate making the ruminant animal more feed efficient and the compound very attractive to economically include in livestock rations.

Reassessing Ruminant Methane Contribution

The environmental impact of livestock production, especially ruminants, has received a lot of attention in both the scientific community and popular media. One of the most discussed aspects of ruminants’ environmental impact is the production of the greenhouse gas, methane. Methane is produced as a natural byproduct of fermentation in the ruminant stomach during the process of feed digestion. The production of methane is not a man-made process and occurs naturally in all wild and domestic ruminant animals.

Wild ruminants in North America include deer, moose, elk, big horn sheep, antelope and bison with bison having the largest population. Estimates of the bison population prior to European settlement of North America varies greatly ranging from 21 to 88 million. And estimates of the total wild ruminant population prior to settlement ranges from 83 to 133 million. Due to lots of factors chief among them the growth in human population, the wild ruminant population has decreased to 30.5 million today and have been replaced by 90 million domestic ruminants.

Do domestic ruminants produce more methane than wild ruminants? Methane emissions factors for bison are similar to that of domestic cattle when fed the same diet, and both are greater than deer and elk. However, diets of wild and domestic ruminants are not necessarily similar. Diets of domestic ruminants are managed by humans and are typically of greater nutritive value than wild ruminants consume, especially during the winter months when vegetation is dormant.

Attempting to account for differences in methane emissions from wild and domestic ruminants, recent research compared the amount of methane from wild ruminants prior to European settlement of North America and current wild and domestic ruminant populations (Figure 1). Due to the wide variation in estimates of bison population, results were computed for low, medium and high bison populations. Based on these data, the amount of methane from domestic ruminants contributing to the increase in global atmospheric methane concentration is less than 100% because a fraction of that methane is replacing naturally produced methane from pre-settlement wild ruminant populations. Doing the math, the proportion of methane emissions from domestic ruminants in North America that is contributing to atmospheric methane concentrations ranges from 50 to -19% depending upon the pre-settlement bison population with an average of 35%.

Several feed additives have been investigated for their ability to reduce enteric methane emissions from domestic ruminants; the most effective include methane inhibitors, electron acceptors, hydrogen sinks, and plant extracts. These feed additives can reduce enteric methane emissions from 10 to 50% depending upon domestic ruminant species and diet, indicating that implementation could mitigate the 35% of domestic ruminant methane emissions that is new to North America since the European settlement. Although most of these feed additives have adverse effects that may hinder their use, one, 3-nitrooxyproponal, reduces methane emissions without negatively affecting animal performance and is in the process of commercialization. 3-nitrooxypropanol also shifts rumen VFA profile toward higher proportions of propionate making the ruminant animal more feed efficient, which is very similar to another feed additive, monensin, which has been widely adopted in ruminant livestock production. Thus, the use of 3-nitrooxypropanol looks very attractive for producers to economically include in livestock rations and could significantly mitigate enteric methane emissions from domestic ruminants.

In conclusion, the extent of domestic ruminants’ contribution to greenhouse gas emissions is not as great as once thought, although livestock production has more environmental impact than methane alone. It appears that we are on the verge of balancing the methane scale as far as domestic ruminant emissions are concerned.

Estimated methane emissions from wild ruminants prior to European settlement of North American Continent based on 3 estimates of the American bison herd (30, 50 and 75 million bison) compared with methane emissions from current population of wild and domestic ruminants. Adapted from Hristov, 2012