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Washington State University Dairy News

June 2020 WSU Dairy Newsletter

Cooperative University Dairy Students Adapt to Challenge of COVID


CUDS (Cooperative University Dairy Students) is a student run group dedicated to running a successful dairy farm while also providing a safe space to teach and learn. “Where the text meets the bucket” is a quote often used to describe the way CUDS members learn. We rely on the community of wonderful staff and faculty at WSU to help guide us on our journey. Anyone who has ever stepped foot on a dairy farm before knows that things change every hour of every day. Simple changes such as fluctuation in milk produced has a domino effect all the way to affecting the amount of money we have to pay our expenses. A very big change that CUDS has had to deal with an along with the rest of the globe is the Covid-19 pandemic. Many parts of society have changed or been shut down due to the pandemic. CUDS was deemed essential by Washington State University administration, meaning we were able to continue working and milking our herd but that does not mean things didn’t change on the dairy. CUDS had to adapt to new rules and regulations set in place by the state and the university in order to stay working and keep everyone safe:

Meetings – All meeting that were previously held in person were converted to online meeting through While switching to online was a bit of a challenge at first, we quickly figured out how to manage the meetings and hold the same standards that were enforced in our in-person meetings. We never leave a question unanswered or a comment unsaid by working together to make sure that all topics are still discussed as thoroughly as ever before.

Shift caps – Generally, when working a shift, the more members there the better because it got the work done faster and was a great way to bond with the team members. While bonding with team members is more important now than ever before because of the distancing, we decided to limit the number of members on a shift to two people to keep our members safe as well as make it easier to distance ourselves while still being able to work together on a shift. Limiting the number of people on a shift at a time would hypothetically extend shift time but our members really worked together to make sure that they are doing their work both effectively and safely. Shift caps have not stopped our members from bonding and in fact it taught them to work better as a team in order to get work done and keep each other safe

Work parties – Work parties are a very important part of CUDS in which the whole group usually meets on a weekend day at the dairy to clean and do chores that need to be done to keep our herd happy and healthy. Work parties are also a great time for the team to work together, bond, and check-in with one another to stay connected. In response to the pandemic CUDS came up with a way to still get all the work done but without putting the group at risk of spreading or contracting Covid-19. The work party tasks were split into separate time slots throughout the day in which one to two of the members went to the dairy to get the task done. As well as going in smaller groups at different times, CUDS members also had to stay in contact with one another to make sure that the groups were not out at the dairy at the same time and therefore defeating the purpose of social distancing. Also, members had to make sure that at least one member knew how to do the task that they signed up for and how to teach it if necessary. CUDS handled these new challenges with ease and made sure that the dairy was still cleaned and our herd was still cared for just as effectively.

Learning opportunities – CUDS focuses on being an experiential learning environment. This is usually done by having groups meet at the dairy to teach and show the members what to do in many different situations. Since groups are no longer an option, we tried to pair one member with the knowledge with one member that wants to learn and we rotate as much as possible so that each of the members still has the same opportunities to learn. We also usually take field trips to other farms around Washington as a way to learn from others and see other dairy techniques. We gave up our spring trip this year to keep both our team safe, as well as other farmers. We have been very understanding of other dairy farmers keeping their distance at a time like this and look forward to meeting with them as soon as it is safe.

Hannah. Armstrong – CUDS public relations chair –



Amber’s Top Ten Tips: Impact of heat stress on dairy cattle well-being


It has been an unpredictable year so far, including the weather. Regardless of when the hot weather decides to hit, our best defense is to be prepared. We know that heat stress causes decreases in milk production and alters cow behavioral patterns, but what are some of the less known impacts of heat stress on dairy cattle well-being? Below are some interesting study results you may want to consider when deciding how to manage heat stress on your dairy.

1. Dry matter intake –During a 45 day dry-off period, cows that received cooling measures during the entire dry period had an almost 10% higher dry matter intake than cows that received cooling measures for only the first half of the dry period (Fabris et al., 2019).

2. Immune system cytokines – Cows housed in a heat stress environment (temperature-humidity index > 68) had higher plasma concentrations of some key immune system cytokines. Higher concentrations of these cytokines (IL-1β, IL-6, IFN-ꝩ, and TNF-α) indicate that heat stress causes an inflammatory response in the cow’s body (Chen et al., 2018)

3. Mucosal defense system – Housing cows in a heat stress environment also causes a stress-induced activation of the mucosal defense system in lactating cows (Koch et al., 2019). Of course, the more energy the cow’s system uses to cope with heat stress, the less energy that is available for milk production.

4. In utero heat stress and calf immunity – Calves exposed to in utero heat stress have lower rates of peripheral blood mononuclear cell (PBMC) proliferation than calves not exposed to in utero heat stress (Tao et al., 2012). This effect can persist until the calves reach 56 days of age. PBMCs are the cells that make up the immune system, in which a low proliferation rate puts the calf at a health risk.

5. In utero heat stress and calf growth – Newborn calves that experienced in utero heat stress have lower plasma insulin, prolactin, and insulin-like growth factor-I concentrations than calves that did not experience in utero heat stress (Guo et al., 2016). Insulin, prolactin, and insulin-like growth factor-I are key components of calf growth and development.

6. In utero heat stress and calf health – Cows that were cooled during the dry period had heavier calves that also had lower body temperatures at calving than calves from cows housed under heat stress conditions during the dry period. Cooled cows also had calves that were more efficient at absorbing IgG from colostrum and gained 0.44 lb/day more than calves from heat-stressed cows (Laporta et al., 2017).

7. In utero heat stress and calf IgG absorption – Calves born to cows exposed to heat stress during the dry period have lower serum IgG concentrations and higher serum cortisol concentrations than calves born to cows housed in a thermoneutral environment during the dry period (Almoosavi et al., 2020). Remember, cortisol is often referred to as the “stress hormone”

8. In utero heat stress affects calf future performance – Heifers born to heat-stressed cows produce 16% less milk for the first 35 weeks of their first lactation than heifers born to cooled cows (Monteiro et al., 2016). Almost 20% more heifers from cooled cows reached their first lactation than heifers from heat-stressed cows.

9. Feed supplements and cow performance – Supplements may help cows cope with heat stress. One supplement fed to heat-stressed cows resulted in lower cow rectal temperatures (Fabris et al., 2017). The same supplement fed to cooled cows resulted in 13% higher milk production than heat-stressed cows that were not fed the supplement.

10. Feed supplements and calf health – Feeding the supplement mentioned in #9 to cows during the dry period impacted calf health, depending on whether cooling was provided to the cows (Skibiel et al., 2017). Calf serum amyloid A (protein associated with inflammation) was higher in calves born to heat-stressed cows than cooled cows. Furthermore, neutrophil (a type of immune cell) function at 10 days of age was higher in calves born to cooled cows that received the supplement than cooled cows that did not receive the supplement.

Amber Adams Progar, Dairy Management Specialist

For list of references, please contact Amber


April 2020 WSU Dairy Newsletter

Amber’s Top Ten Tips: Farmer well-being


As I sat down to choose a topic for this article, I couldn’t stop thinking about the difficult times we are currently facing as a society. COVID-19 is affecting all our lives. It pangs me to watch milk being dumped down the drain, while many school-aged children won’t receive milk with their lunch (if they receive a lunch) today because of school closures. It is during times like this that we are pushed to the limits and our well-being is threatened. This is why today’s article will focus on the people that make the dairy industry thrive, YOU. My hope is that the information below will help you realize that you are not alone, your well-being matters, and tools are available to help you improve your well-being.


  1. Prevalence of stress among dairy farmers – A survey of 265 Finnish dairy farmers revealed that 42% of the farmers were stressed and 9% of them experienced severe burnout (Kallioniemi et al., 2016).
  2. Prevalence of anxiety and depression among dairy farmers – Out of 170 Midwestern U.S. dairy farmers surveyed, 71% of them met the criteria for Generalized Anxiety Disorder and 53% of them met the criteria for Major Depressive Disorder. Personal finances and time pressures were listed as the greatest concerns (Rudolphi et al., 2020).
  3. Farmer well-being influences animal well-being – Over 900 Norwegian dairy farmers participated in a study in which farmer well-being was compared to animal well-being. Farmers with lower levels of stress and better well-being had animals with better well-being (cow health, longevity, fertility, etc.; Hansen and Østerås, 2019).
  4. Farming pressures – In Wales, 582 dairy and beef cattle farmers identified the top five farming pressures as: finances; weather; tuberculosis; paperwork; and farm management. Farmers who identified finances as the key pressure were more likely to have a lower well-being (Crimes and Enticott, 2019).
  5. Importance of social support – Among 121 Irish farmers, increases in financial and non-financial stress caused increases in farmer anxiety and depression. However, farmers with strong social support had less non-financial farm stress, as well as fewer cases of anxiety and depression (Furey et al., 2016).
  6. Coping with farming pressures – Thirty-two Canadian male farmers participated in intensive interviews, in which all farmers agreed that work breaks and vacations were crucial coping strategies. Time spent with family was listed as particularly powerful a coping strategy (Roy et al., 2017).
  7. Positive impacts on dairy farmer well-being – Finnish dairy farmers identified family, working with cattle, healthy farm animals, a reasonable workload, and a sustainable farm economy as factors that have a positive impact on dairy farmer well-being (Kallioniemi et al., 2018).
  8. Relationship between mental health and physical health – A survey of 79 Australian dairy farmers showed that farmers with higher levels of exhaustion and stress experienced lower levels of physical and mental health. On the other hand, farmers who practiced mindfulness had better physical and mental health than farmers who didn’t practice mindfulness (Eddy et al., 2019).
  9. Barriers to seeking help – A focus group of Australian farmers, farmers’ partners, and general practitioners emphasized that farming is more than just employment, it is a lifestyle. The focus group stated that seeking help requires time away from work, which is a key barrier. Finances may also present a barrier to seeking help (Vayro et al., 2020).
  10. Role of ag professionals – Ag professionals (veterinarians, farm consultants, etc.) have established relationships with dairy farmers. They play a key role in identifying, mitigating, and supporting farmers during difficult times (Stanley-Clarke, 2019).

Remember: you are not alone, your well-being matters, and tools are available to help you improve your well-being.

Amber Adams Progar, Dairy Management Specialist


Crimes and Enticott. 2019. Assessing the social and psychological impacts of endemic animal disease amongst farmers. Front. Vet. Sci. 6:342.

Eddy et al. 2019. Trait mindfulness helps explain the relationships between job stress, physiological reactivity, and self-perceived health. J. Occup. Environ. Med. 61:e12-e18.

Furey et al. 2016. The roles of financial threat, social support, work stress, and mental distress in dairy farmers’ expectations of injury. Front. Public Health 4:126.

Hansen and Østerås. 2019. Farmer welfare and animal welfare- Exploring the relationship between farmer’s occupational well-being and stress, farm expansion and animal welfare. Prev. Vet. Med. 170: 104741.

Kallioniemi et al. 2016. Stress and burnout among Finnish dairy farmers. J. Agromedicine 21 (3): 259-268.

Kallioniemi et al. 2018. Job resources and work engagement among Finnish dairy farmers. J. Agromedicine  23:249-261.

Roy et al. 2017. “Do it all by myself”: a salutogenic approach of masculine health practice among farming men coping with stress. Am. J. Mens Health 11:1536-1546.

Rudolphi et al. 2020. Depression, anxiety and stress among young farmers and ranchers: a pilot study. Community Ment. Health J. 56:126–134.

Stanley-Clarke. 2019. The role of agricultural professionals in identifying, mitigating and supporting farming families during times of stress: findings of a qualitative study. Aust. J. Rural Health 27:203–209.

Vayro et al. 2020. ‘Farming is not just an occupation [but] a whole lifestyle’: a qualitative examination of lifestyle and cultural factors affecting mental health help-seeking in Australian farmers. Sociol. Rural. 60:151-173.

December 2019 WSU Dairy Newsletter

Donations to CUDS Program Leads to Memorable Field Trip

Group of CUDS students standing in aisle at a dairyAt the beginning of 2019, we held our first ever WSU Cooperative University Dairy Students (CUDS) reunion to celebrate the program’s 41 years of excellence. Former CUDS members, family, and friends gathered to reminisce and share stories about how CUDS impacted them. We also began a fundraising drive for CUDS, in which Dr. Joe Hillers announced he would match up to $5,000 in donations. With the generous support of Dr. Hillers and our donors, we reached our fundraising goal.

For most CUDS members, the only dairy experience they have is from working with the cattle at the WSU Knott Dairy Center. This is one reason why we make CUDS field trips a priority. The CUDS motto is “where the text meets the bucket”, and going on field trips is one way our CUDS members learn first-hand how other farmers manage their dairies. The fundraiser earlier this year allowed us to take CUDS members to four dairies in Western Washington last month. CUDS members learned about the cheese making process at Cherry Valley Dairy, witnessed robotic milkers in action at Paradise Jerseys, explored farmland stewardship practices at Steensma Dairy, and business diversification strategies at Hy-Grass Farms. We visited farmers that use cutting-edge technology and farmers that prefer to keep things simple. The diversity of these farms was incredible, we cannot thank them enough for sharing their time and expertise with us.

We would like to send a special thank you to Dr. Hillers and the donors that made this experience possible for the CUDS members. It was truly memorable.

LEADS Graduates Ready to Teach Safety

LEADS graduates pose in ballroom with their certificates.Teaching safety to employees can be difficult. It is even more difficult to make safety training fun and engaging. Graduates from the Leaders Enabling Advanced Dairy Safety (LEADS) program learned how to help their employees learn safe practices and received tools they can use on their dairy to make safety trainings more effective. The LEADS training is one part of a larger effort to build a Dairy Safety Network in Washington State. It is a collaborative effort among the Washington State Dairy Federation, University of Washington, and Washington State University.

We held two LEADS training sessions in 2019 and will offer two sessions in 2020. During this 4-hour training, participants learned how an effective safety training could help reduce the incidences of the most common cattle-related employee injuries on Washington dairies. Participants also completed leadership training that prepared them to become the teacher. It is a train-the-trainer program designed specifically for dairy owners and managers.

Our LEADS graduates reported that 100% of them learned something new from the training. We hope you can join us for one of our upcoming LEADS training sessions. Upcoming locations include Moses Lake and Lynden. Please contact me at or 509-335-0673 for more information about LEADS.

Funding and support for this project has been provided by the State of Washington, Department of Labor & Industries, Safety & Health Investment Projects.

September 2019 WSU Dairy Newsletter

Cows, Greenhouse Gases, and Nature’s Carbon Cycle

There was an article published in the July 2019 issue of Hoard’s Dairyman entitled “Cattle are part of nature’s carbon cycle”. The title probably didn’t catch your eye, but the content presents a very different picture of the role that dairy cows (and beef cattle) have in regard to greenhouse gases and climate change.

A few excerpts from the paper are:

“…we have seen the media place blame for our changing climate on cattle. For dairy cows in the U.S., this claim cannot be supported by science…”

“Methane is a powerful greenhouse gas that along with carbon dioxide nitrous oxide, and some other compounds in the atmosphere create a blanket around our planet.”

“Without this atmospheric blanket, the earth would be too cold for us to survive.”

“The current problem is that concentrations of these gases are rising, which is thickening the blanket. This leads to an elevation in global temperatures and related climate changes.”

“The methane that cows produce is part of a natural carbon cycle that has been happening since the beginning of life on our planet.”

As shown in the figure below, CO2 is fixed via photosynthesis into plant carbohydrates. The plant carbohydrates are fed to animals where some of the plant carbohydrates get converted to methane and end up in the atmosphere. In about a 12 year period of time most of the methane gets converted back to CO2, and the cycle continues.

Cycle of Carbon dioxide to Plant carbohydrates to Feed for cows to Methane

The step that is basically ignored is that methane is changed back to CO2 within a very short period of time compared to CO2 created by burning fossil fuels.

If you consider that we have less dairy cows now than 50 years ago, that cows are now more efficient, this then translates to less of an impact on atmospheric greenhouse gases today than in prior decades.

Does this mean we shouldn’t adopt practices that reduce methane emissions from cows and manure, certainly not. If new management practices and feeding strategies reduce methane emissions, and are profitable, their adoption should be considered.

Dairy can be part of the answer to atmospheric levels of CO2; let’s make sure that the message to the public is that dairy is a part of the solution, not a part of the problem.

Amber’s Top Ten Tips: Human-dairy Heifer Interactions

Two dairy calvesOne of the most common causes of employee injuries on dairies is cattle. These injuries are a result of human-dairy cattle interactions that went wrong. Providing dairy cattle handling training is the first step in preventing cattle-related injuries. While many different training formats are available, including videos and lectures, which training improves cattle learning? We often focus on providing the most effective training for employees that we forget that training cattle is also beneficial. Cattle are capable of learning during training. I collaborated with two veterinarians at the University of Pennsylvania (Dr. Michaela Kristula and Dr. Meggan Hain) and an expert handling trainer (Dr. Don Höglund) to conduct a study aimed at determining how weaned heifers respond to training. Our research was published last month in the Journal of Extension. Below are some highlights about what we learned:

  1. Heifers are more difficult to handle.

    Minnesota dairy producers reported in a 2014 survey that two of the most difficult groups of cattle to handle are postpartum heifers and calves (Sorge et al., 2014).

  2. Relationship between heifer walking and slipping behavior.

    We conducted a series of handling tests during our study, in which we herded the heifers from one end of their pen to the opposite end of their pen six consecutive times. Heifers that walked during handling were significantly less likely to slip. This is one reason it is important to move cattle slowly. (Adams Progar et al., 2019)

  3. Facing and approaching the handle.

    Heifers that faced the handler during the tests were more likely to approach the handler. If heifers face the handler, then they are not facing the direction of their destination. Approaching the handler is counterproductive to safely moving cattle, as we rely on an animal’s flight zone to move them safely. (Adams Progar et al., 2019)

  4. Facing and approaching the handler.

    It was interesting to note that when heifers faced the handler, they were significantly less likely to walk during handling. (Adams Progar et al., 2019)

  5. Repeat handling affects heifer walking behavior.

    We conducted handling tests over the course of two days so that all 36 heifers were handled on both days. While only 56% of heifers walked during tests on the first day, 75% of heifers walked during tests on the second day. Repeated handling of weaned heifers may help with their handling ease. (Adams Progar et al., 2019)

  6. Facing the handler behavior affected repeated handling.

    Throughout the first day of training, 44% of heifers faced the handler during tests; whereas, 31% of heifers faced the handler during tests on the second day. Once again, repeated handling of weaned heifers may be beneficial. (Adams Progar et al., 2019)

  7. Time of day affects heifer walking behavior.

    Over the course of both training days, all heifers were handled once in the morning and once in the afternoon. Fifty-four percent of heifers walked during the morning tests, and 78% of heifers walked during the afternoon tests. (Adams Progar et al., 2019).

  8. Fewer occurrences of slipping occurred in afternoon.

    Fourteen percent of heifers slipped during handling in the morning and 4% of heifers slipped during afternoon handling tests. Training heifers during the afternoon may be more effective than training during the morning. (Adams Progar et al., 2019).

  9. Type of handling training affects heifer walking behavior.

    Handlers who received the lecture only training had 34% of heifers walk during tests; however, handlers who received the hands-on workshop in addition to the lecture had 81% of heifers walk. (Adams Progar et al., 2019).

  10. Type of handling training affects the occurrences of slipping during handling.

    Handlers who received only the lecture training had 17% of heifers slip during handling, but handlers who received the hands-on workshop had 5% of heifers slip (Adams Progar et al., 2019).


  • Adams Progar et al. 2019. Dairy cattle handling Extension programs: training workers and cattle. Journal of Extension
  • Sorge et al. 2014. Perception of the importance of human–animal interactions on cattle flow and worker safety on Minnesota dairy farms. Journal of Dairy Science 97:4632–4638.

Do you know a dairy leader interested in a unique training program?

The Leaders Enabling Advanced Dairy Safety (LEADS) program will be offered beginning Fall 2019. LEADS is a train-the-trainer program focused on preventing the most common types of employee injuries caused by cattle on dairies. Participants will complete a 4-hour training that will teach them how to provide an effective cattle handling safety training and prevent cattle-related injuries on their dairies.

Registration will be limited. We are planning to host four training sessions throughout Washington State. More details will be released soon. If you would like more information about this training, please contact Amber Adams Progar at 509-335-0673 or

Coming Soon: LEADS. An animal handling safety training program for dairy leaders.

June 2019 WSU Dairy Newsletter

Amber’s Top Ten Tips: Cow Behavior and Automated Milking Systems

Interested in automated milking systems? These systems have a lot to offer, but they are not a solution for all dairies. Automated milking systems are an investment. Although several management decisions can determine whether an automated milking system succeeds, understanding cow behavior can also influence a system’s successfulness. Here are some thoughts on how cow behavior may affect the success of an automated milking system:

  1. Stress and milk yield

    When transitioning cows from a conventional system to an automated milking system, milk yield/cow can decrease by 45% during the first 24 hours of the transition, but milk yield should recover within 4 days. Changing a cow’s routine can cause a stress response that suppresses milk letdown. (Jacobs and Siegford, 2012)

  2. Stress-related behaviors during milking

    Vocalization and elimination behaviors occur more frequently when cows are stressed. Although these behaviors increase during milking when cows are transitioning to an automated milking system, vocalizations and eliminations decrease by 84% and 71% within the first 24 hours of the transition. (Jacobs and Siegford, 2012)

  3. Concentrate allocation in automated milking units

    Feeding cows 11 lbs/day versus 1.1 lbs/day of concentrate during milking does not appear to affect the number of voluntary visits to the milking unit. (Paddick et al., 2019)

  4. Automatic feed delivery and cow lying time

    Lying time is important for cows. They will sometimes alter their behavioral patterns by decreasing the amount of time they spend performing other behaviors to allow more time for lying. Feeding cows with an automated feed system 11 times/day versus 6 times/day did not affect the total daily lying time (average of 12 hours/day). (Mattachini et al., 2019)

  5. Use of an automatic herding system

    Engineers from Israel designed an automatic herding system that uses mobile fences to herd cows to the automatic milking unit. This herding system increased milking frequency by 45%, milk yield by 15%, and decreased labor time to fetch cows by 80%. (Drach et al., 2017).

  6. Ratio of cows to automatic milking units

    Milking frequency/cow per day is negatively related to the ratio of cows to automatic milking units. (King et al., 2016)

  7. Feed bunk activity

    With the ability to be milked on their own schedule, cows milked by automatic milking systems typically prefer to eat during the day, avoiding the late evening and early morning hours. It is important to note that environmental stressors, such as heat stress, can affect cow feeding behavior. (Wagner-Storch and Palmer, 2003)

  8. Concentrate content and milking visits

    When compared against a standard concentrate, a barley-oats concentrate fed during milking caused an increase in the number of cow visits to the automated milking unit and a decrease in the number of fetches. (Madsen et al., 2010)

  9. Waiting area

    With the use of control gates, the open waiting area in front of the automated milking unit should be large enough to decrease competition. Dominant cows spend an average of 13 minutes in the waiting area and subordinate cows spend an average of 20 minutes in the waiting area. (Melin et al., 2006)

  10. Automated milking unit exit area

    Cows exiting the automated milking unit require 54% more time to exit the unit if other cows are near the exit gate than if no cows are near the exit gate. (Jacobs et al., 2012)


  • Drach et al. 2017. Automatic herding reduces labour and increases milking frequency in robotic milking. Biosyst. Eng. 155:134-141.
  • Jacobs, J. A., and J. M. Siegford. 2012. Lactating dairy cows adapt quickly to being milked by an automatic milking system. J. Dairy Sci. 95:1575-1584.
  • Jacobs et al. 2012. Dairy cow behavior affects the availability of an automatic milking system. J Dairy Sci. 95:2186-2194.
  • King et al. 2016. Associations of herd-level housing, management, and lameness prevalence with productivity and cow behavior in herds with automated milking systems. J. Dairy Sci. 99:9069–9079.
  • Madsen et al. 2010. Concentrate composition for automatic milking systems-effect on milking frequency. Livest. Sci. 127:45-50.
  • Mattachini et al. 2019. Effects of feeding frequency on the lying behavior of dairy cows in a loose housing with automatic feeding and milking system. Animals 9(121).
  • Melin et al. 2006. Cow traffic in relation to social rank and motivation of cows in an automatic milking system with control gates and an open waiting area. Appl. Anim. Behav. Sci. 96:201-214.
  • Paddick et al. 2019. Effect of the amount of concentrate offered in an automated milking system on dry matter intake, milk yield, milk composition, ruminal digestion, and behavior of primiparous Holstein cows fed isocaloric diets. J. Dairy Sci. 102:2173-2187.
  • Wagner-Storch, A. M. and R. W. Palmer. 2003. Feeding behavior, milking behavior, and milk visits of cows milked in a parlor versus an automatic milking system. J. Dairy Sci. 86:1494-1502.

Nitrate: Know Your Units of Measure

Is it nitrate or is it nitrate-nitrogen? Are the units in percent dry matter (% DM), parts per million (ppm), or milligrams per kilogram (mg/kg)?

Testing for nitrate is common practice by dairy farmers. Soil, crops and water may be tested. The nitrate content in soil is used to estimate the amount of nitrogen that will be available for crop growth. The nitrate content in both forage and drinking water are commonly used to monitor the amount of nitrate-N that cows might consume in order prevent nitrate toxicity.

Nitrate testing can seem straight forward and simple. However, the result might be expressed in different forms, leading to confusion. For instance, let’s start with soil. The recommended soil depth to obtain a sample is 1 foot, or in multiples of 1 foot. It is common for the test result to be reported as nitrate-N and expressed as mg/kg, ppm, or pounds per acre. Most fertilizer guides use nitrate-N as the unit of expression when interpreting soil analyses. What if a test result is expressed as nitrate (NO3) rather than nitrate-N (NO3-N)? If so, a conversion factor is needed.

Table 1. Conversion between nitrate (NO3) and nitrate-nitrogen (NO3-N)
To convert To Multiply by
Nitrate (NO3) Nitrate-nitrogen (NO3-N) 0.22
Nitrate-nitrogen (NO3-N) Nitrate (NO3) 4.43

The reason for this conversion is that nitrate molecule weighs 62 grams per mole; the nitrogen content of nitrate is 22.5% of the total weight of the molecule. (Source: R. Smith and M. Cahn, July 30, 2012, retrieved from on June 5, 2019).

A value of 6.9 mg/kg of nitrate-N would be 6.9 × 4.43 = 30.6 mg/kg nitrate.

Let’s start with soil. For dairy forage crops, the recommended soil sampling depth is typically one foot. Most commonly, the test result is reported as nitrate-N and expressed as mg/kg. The lab may also convert the result to pounds per acre. Most fertilizer guides use nitrate-N as the unit of expression when interpreting soil analyses.

An example of conversion of soil test nitrate-N is shown below. This example is from a commercial soil test lab that used a conversion factor of 3.5 to convert mg/kg to lbs/acre. The conversion factor of 3.5 assumes that a one acre-foot sample of soil weighs 3.5 million pounds (3.5 lb per acre-foot = 1 ppm). A very common factor to use is 3.5.

Table 2. Concentration of Nitrate-N in Soil
Depth Nitrate-N (mg/kg) Nitrate
inches mg/kg lbs/acre mg/kg lbs/acre
0-12 6.9 24.26 30.6 107

Can a soil sample be taken at a depth of 0 – 6 inches and the results be translated to a depth of 0 – 12 inches or one foot — NO!

The attempt to use a 6 inch soil sample to represent a 1 foot sample will either over or underestimate the corresponding value for the 1 foot sample.

As an example of underestimating the amount of nitrate-N in one ft of soil with a six inch soil sample, if a sample were obtained from the first 6 inches in the fall after it had started raining, the nitrate in soil may have been pushed to the 7 – 12 inch depth and not accounted.

As an example of overestimating the amount of nitrate-N in one foot of soil with a six inch soil sample, if fertilizer had just recently been surface applied and had not been distributed within the top foot of soil, the nitrate in the top six inches would result in an overestimation of nutrients available to the crop.

All Forms of Nitrogen

The other form of nitrogen available for crop growth is organic nitrogen found in soil organic matter. During a growing season, some of the organic nitrogen present in soil organic matter (OM) will become available for plant growth due to the biological activity in the soil. If the top foot of soil weighs approximately 3.5 million pounds, as previously noted, a soil with 5% OM has 175,000 pounds of OM present in the top foot. For soils up to 5% OM, approximately 20 pounds of nitrogen will become available to the crop for each percent OM. Thus a 2% OM soil will provide approximately 40 pounds of plant available nitrogen per acre each year and a 5% OM soil will provide 100# per acre.

Washington’s Natural Resources Conservation Service (NRCS WA) has supplements to the national Agricultural Waste Field Management Handbook, or AWFMH, Table 11-9.

The table below, taken from an actual soil test, shows the accounting of nitrogen from three sources, nitrate-N, N from OM, and N from ammonia-N. In this soil sample, there was a total of 67 pounds of tested N with 7 pounds of ammonia-N, and 38 pounds of N in OM (1.9 × 20 = 38) and 22 pounds of nitrate-N.

Table 3. Example Soil Test Report
Ammonium-N mg/kg 2.3 7
Organic Matter W.B. % 1.9 ENR: 38
Depth Nitrate-N Sulfate-S Moisture
inches mg/kg lbs/acre mg/kg inches
0 – 12 6.9 22 9  
Totals 6.9 22 9  
Sum of Tested N: 67 lbs/acre N

Analyzing a forage sample or water sample for nitrate follows the same logic as discussed for soil.

Table 4. Guidelines for Limits of Nitrate in Feeds and Water
Percent (%) NO3 on 100% dry matter (DM) basis Comment
Original Source: Hoard’s Dairyman August 25, 1970.
Less than 0.44% (4,400 ppm) Safe
0.44 to 0.88% (4,400 to 8,800 ppm) Generally safe when fed balanced rations. Best to limit to half of the total dry ration for pregnant animals. In addition, be sure water is low in nitrate.
0.88 to 1.5% (8,800 to 15,000 ppm) Limit amount to less than half of total dry ration. Be sure water is safe. Be sure ration is well fortified with energy, minerals, and vitamin A.
Over 1.5% (15,000 ppm) Potentially Toxic – do not feed
Table 5. Guide of Use of Water with Known Nitrate Content
PPM of NO3 Comment
Original Source: Hoard’s Dairyman August 25, 1970.
Less than 44 Generally regarded as safe for all animals and humans
44 to 88 Questionable or risky for humans, especially children and pregnant women. Safe for livestock unless feed also has high levels.
88 to 176 Considered unsafe for humans. Might cause problems for livestock, especially swine and poultry.
176 to 440 Unsafe for humans and risky for livestock. Be sure feed is low in nitrates and be sure as well balanced ration is fed. Fortify ration with extra vitamin A.
440 to 880 Dangerous and should not be used. General or nonspecific symptoms such as poor appetite are likely to develop. Water apt to be contaminated with other foreign substances. When allowed free-choice to cows on a good ration, acute toxicity not likely.
Over 880 Don’t use. Acute toxicity and some death losses might occur in swine. Probably too much total intake for ruminants on usual feeds.

March 2019 WSU Dairy Newsletter

Working together to build a Dairy Safety Network

Dairy cows standing in hay.
We have exciting news to share! The Washington State Dairy Federation, University of Washington’s Pacific Northwest Agricultural Safety and Health Center, and WSU’s Dairy Cattle Behavior and Welfare program (Dr Adams Progar) are collaborating to make safety training materials more accessible and effective for dairies. Our project has three parts: 1) develop an online interactive safety training toolkit; 2) offer in-person workshops to teach dairy owners and managers how to use the safety training toolkit materials; and 3) create an interactive train-the-trainer program that focuses on teaching employees how to minimize risks associated with cattle-related injuries.

Dairy Safety Training Toolkit

Where do you look for safety training materials? Do you ever struggle to find materials on a specific safety topic? Our online safety training toolkit will hopefully become your go-to for all dairy-related safety topics. One of the best features of this resource is that you will be able to interact with the toolkit moderators and other toolkit users. This system will allow you to provide instant feedback on how the materials can be improved and allows you to incorporate tips from other toolkit users. We are currently working on developing the toolkit and are looking for beta testers. Please let us know if you are interested in helping us out as a beta tester.

In-person Workshops

We held our first workshop at the Agriculture Safety Day on February 5th, 2019. Our topics included on-farm communication, effectiveness of different employee training methods, and farm-to-farm networking to improve safety training materials. If you have any topic suggestions for next year’s Agriculture Safety Day, please let us know.

Train-the-Trainer Program

Several dairy cattle handling training programs are available to you and your employees. Most programs focus on training your employees to safely move cattle. The Train-the-Trainer program we are developing is focused on injury prevention. Our goal is to identify the most common employee injuries that are cattle-related on dairies and design a training that specifically targets how to minimize the risks associated with those injuries. We will train dairy managers/safety coordinators so that they have the tools they need to provide this training to the employees on their dairies. This safety training will be offered in each region of Washington State later this year, so please stay tuned for more information.

Update on Struvite as a Phosphorus Source for Modern Alfalfa Systems

The WSU Livestock Nutrient Management program has teamed up with WSU’s forage specialist Dr. Steve Norberg, and two Washington alfalfa growers to demonstrate struvite’s performance as a recycled phosphorus source for alfalfa. Struvite (6-29-0), also known as magnesium ammonium phosphate, is a medium-release rate fertilizer that is recovered from liquid manure or wastewater. Ongoing research in eastern Washington with 2 field demonstrations and multiple plot studies confirm the findings of previous studies’  that alfalfa fertilized with Struvite has comparable yields and quality to alfalfa fertilized with MAP (11-52-0). We paid close attention to the first cutting’s response to Struvite to see if its lower solubility affected its ability to meet alfalfa’s early growth requirements.

The field demonstrations were on 60-80 acre fields in Moses Lake and Kittitas where we compared Struvite and a Struvite-MAP mixture (70%-30% of P, respectively) to MAP. Struvite alone was applied before a new seeding of alfalfa on Farm 1, while the Struvite-MAP mixture was surface applied to an established stand on Farm 2. Data was gathered from 2 of 3 cuttings at Farm 1 and 4 cuttings at Farm 2 in the first year. Results showed Struvite produced similar alfalfa yields, phosphorus uptake, and quality as MAP (Table 1).

Table 1. Alfalfa hay yields, P uptake, and relative feed value (RFV) from 2018
Yield (tons/acre) Average Tissue P (%)
Farm Fertilizer Total 1st Cut Season 1st Cut Avg. RFV*
*The Relative Feed Value reflects the digestibility and intake potential of feeds, where greater numbers mean better quality.
1 MAP 7.3 2.0 0.28 0.25 181
Struvite 7.3 2.3 0.28 0.24 168
2 MAP 7.5 2.4 0.27 0.26 155
Struvite + MAP 7.1 2.2 0.27 0.28 165

Two simultaneous plot studies (< 1 acre each) were conducted by Dr. Norberg in Prosser to compare agronomic performance of different combinations of Struvite and MAP mixtures on fall and spring planted alfalfa. Plots were randomly fertilized at a constant rate with one of 7 different mixtures of MAP:Struvite (100:0, 75:25, 50:50, 37.5:62.5, 25:75, 12.5: 87.5, 0:100) just before planting, or left as an unfertilized check. The fall-planted alfalfa was cut 5 times in 2018, while spring-planted was only cut 3 times. The source of P, whether MAP or Struvite, did not have a significant effect on yield or P uptake in the first cutting and season-wide, regardless of planting time (Figures 1 and 2).

In short, what we’ve learned so far from the field demonstrations with the supporting data of the plotwork is that Struvite can provide enough P in the first year after fertilization to reach comparable yields and P uptake as MAP. Furthermore, the similarity in the first cutting after a new seeding in both studies has shown Struvite is available to meet the immediate needs for early establishment of alfalfa. This ongoing research will continue for a second harvest season this summer to compare the long-term performance of the two fertilizers.

Line graph showing Total Dry Matter Yield First Year (tons/acre) vs. MAP: Struvide Fertilizer Ratio Applied Prior to Planting for Fall- and Spring-Planted Alfalfa
Figure 1. 2018 Accumulative Dry Matter Yield and Average Phosphorus Content in 2018 of Fall* and Spring** Planted Alfalfa Fertilized with MAP and Struvite-MAP mixtures [*Fall planted data shown above is across 5 cuttings for dry matter yield, and 4 cuttings for P concentration.] [**Spring planted data shown above is across 3 cuttings for both DM yield and P concentration]
Line graph showing Total Dry Matter Yield 1st Cut (tons/acre) vs. MAP: Struvite Fertilizer Ratio Applied Prior to Planting for Fall- and Spring-Planted Alfalfa
Figure 2. Dry Matter Yield and Average Phosphorus Content at First Cutting in 2018 of Fall and Spring Planted Alfalfa Fertilized with MAP and Struvite-MAP mixtures.

Pest Bird Management Workshops

Class flyer featuring birds covering piles of feed next to cows.

Pest Bird Management Workshops

Includes on-farm falconry and drone demonstrations.

  • March 6, 2019, 10:00 AM to Noon
    Dutch Mothers Restaurant
    405 Front Street, Lynden, WA
  • March 7, 2019, 10:00 AM to Noon
    Snipes Restaurant
    905 Yakima Valley Highway, Sunnyside, WA

For more information:
Amber Adams Progar

December 2018 WSU Dairy Newsletter

Dairy Program Weekend at WSU

January 24 and 25, 2019

Please join us for WSU Dairy Program Weekend In Pullman. All events will be held in the Ensminger Pavilion, 455 Lincoln Dr.

On Friday January 24 and Saturday the 25 the annual CUDS review will occur with selected industry reviewers.

On Friday night, January 24, the WSU Dairy Club will host their annual Dairy Club Banquet (including a silent auction) from 5:30 – 8:00 PM. Please RSVP to for banquet reservations, cash will be accepted at the door.

On Saturday January 25, a CUDS reunion will be held beginning at 3 PM and concluding at 8 PM. Reservations ( are required for the catered meal.

A block of rooms has been reserved at the Residence Inn (reservation link)

Please direct questions to Joe Harrison.

Amber’s Top Ten Tips: What We Learned About Pest Birds On Washington Dairies

Winter is the season for colder temperatures, holiday celebrations, and pest bird problems. Dairy barns attract more pest birds during the colder weather because they offer a warm shelter with plentiful food. The influx of pest birds on dairies results in lost feed from bird depredation, feed spoilage, building depreciation, increased costs for bird deterrence, and potentially negative consequences on cow well-being. Our Pest Bird Management Research Team conducted a survey and on-farm study over the last year to gain insight on the “big picture” of pest bird damage on Washington dairies. Here is a list of 10 things we learned:

  1. Number of birds on dairies

    During the peak of bird presence on dairies, 51% of surveyed farmers reported that 1,000 – 10,000 birds are present per day.

  2. Birds that cause the most damage

    European starlings, pigeons, and sparrows were the top three bird species that farmers identified as causing damage on Eastern Washington dairies. Western Washington dairies reported European starlings, pigeons, and crows were the top three damage-causing birds.

  3. Popular bird deterrence methods

    The three most popular bird deterrence methods used by surveyed farmers were shooting, netting, and trapping. However, 88% of the farmers that used shooting for bird deterrence considered the method to only be somewhat effective.

  4. Alternative bird deterrence methods

    Approximately 10% of surveyed farmers reported that the presence of predator birds (such as hawks and falcons) or the use of predator calls are alternative methods they use on their dairies to deter birds.

  5. Johne’s disease and Salmonella

    Dairies with more than 10,000 birds present per day were more likely to report the presence of Johne’s disease or Salmonella within their herds.

  6. Salmonella, Escherichia coli (E. coli), and Campylobacter in bird feces

    We collected fresh bird feces from the feed bunks of 16 pens (five different dairies) across Washington. Samples were analyzed for Salmonella, E. coli, and Campylobacter. Salmonella was not detected in any samples, but about 39% of the samples were positive for E. coli. Only one sample was positive for Campylobacter jejuni, bacteria linked to abortions in cattle.

  7. Cow aggression at the feed bunk

    We recorded cow and bird behaviors at the feed bunks of 16 pens (5 different dairies). As the number of birds at the feed bunk increased, cows showed more aggression toward the birds. This means that cows were spending more time displaying aggressive behaviors, interrupting their time spent eating.

  8. Economics of feed loss due to bird depredation

    Surveyed farmers reported losing an average of 4.4% of their feed to birds. This adds up to be about $14.7 million/year of losses.

  9. Washington’s gross domestic product (GDP)

    Our models predict that feed loss from bird depredation on dairies will result in a loss of 154 jobs and $12.6 million in Washington’s GDP over five years.

  10. Birds deplete nutrients in cattle feed

    Our team collected fresh feed samples from 19 pens (5 different dairies) to measure the net energy for lactation, total digestible nutrients, fat, crude fiber, ash, dry matter, and protein content. These samples represented the balanced diet formulated for the cows (what the cows were meant to eat). After the delivery of fresh feed, birds were allowed to eat at the feed bunk uninterrupted while the cows were being milked. After 30 minutes, we collected another sample of the feed from an area where birds had been eating. These samples represented the diet that was available to cows after bird depredation (what the cows actually get to eat). Our most shocking result was that farms lost up to 31% of net energy for lactation. This loss occurred after only 30 minutes of bird depredation!

We sure learned a lot over the last year, but we only scratched the surface of the problem. Our next steps are to test some alternative bird deterrence methods to determine which methods may be more economically feasible and long-lasting. Please contact us if you have any questions or ideas on how we can help dairy farmers manage this problem.

This project is funded by the Western Sustainable Agriculture Research and Education Program (Project # SW16-013). Our Pest Bird Management Research Team includes Stephanie Shwiff (USDA-APHIS), Karen Steensma (Trinity Western University), Susan Kerr (WSU), Julie Elser (USDA-APHIS), Tyler Caskin (WSU), and Amber Adams Progar (WSU).

Register to Attend the 2019 Western Dairy Management Conference!

Monday, February 25 – Thursday, February 28, 2019

Peppermill Casino Resort Spa – Reno, NV

WDMC Early Bird Registration Deadline

February 1, 2019

Hotel Room Reservation Deadline

February 3, 2019

Complete Schedules and Registration Information for Meetings (CDBC and WDMC) and Hotel

September 2018 WSU Dairy Newsletter

Amber’s Top Ten Tips: Calf Jackets and Jersey Calves

Across the United States, calf mortality rates are between 5 and 7%. Changes in weather or environmental conditions are associated with an increased risk for calf illnesses. This is why we see more calf illnesses when the seasons change. Jersey calves, in particular, are susceptible to colder weather because of their small body frame. Using calf jackets is one management practice we use to help calves cope with cold weather conditions. Some farmers have witnessed the benefits of calf jackets firsthand, while others are not convinced that jackets are effective. Scientifically, we have only a handful of research studies that measured the effectiveness of calf jackets and the results are conflicting. During the winter of 2017, the Adams Progar Lab at WSU completed a study on a Washington State dairy to measure how the use of calf jackets in Jersey calves impacts calf health, behavior, and growth during the first two weeks of age. Please consider our key findings below when deciding whether providing calf jackets to your calves would be beneficial and economical.

  1. Body temperature

    Calves that wore jackets and calves that did not wear jackets had similar body temperatures. Body temperatures averaged 101.28 °F throughout the study. Note: a calf’s body will allocate more energy towards maintaining internal body temperature during cold weather, resulting in less energy available for calf health and growth.

  2. Growth

    No difference in growth or average daily gain was found between calves that wore jackets and calves that didn’t wear jackets. Overall, average daily gain from birth to weaning was 1.12 lbs/day, with calves weaning at 129.4 lbs. Note: the American Jersey Cattle Association recommends an average daily gain from birth to first pregnancy of about 1.2 lbs/day.

  3. Behavior

    All calves spent an average of 66% of their first two weeks of life lying down, regardless of whether they wore a jacket. Calves that wore jackets were not more active than calves that did not wear jackets. Note: during the first two weeks of life, calves typically spend the majority (50% or more) of their time each day lying down.

  4. Health

    Calves that wore jackets and calves that did not wear jackets were similar in the number of treatments they received for illnesses. Calves that wore jackets were not healthier than calves that did not wear jackets. Note: this result matches results from previous studies.

  5. Age and health

    Over the course of the study, 98% of health treatments for calf illnesses occurred during when calves were 2 – 3 weeks of age (see Figure 1). Note: diarrhea was the most common symptom documented during this timeframe.

  6. Use of small equipment for on-farm data collection

    We used two types of small devices to collect body temperature data and housing conditions data. For body temperature data, we used temperature recording devices (iButton® DS1922L, Maxim, San Jose, CA) and for housing conditions, we used HOBO® data loggers (ONSET U12-012, Bourne, MA). Note: please contact me if you are interested in learning how to use these inexpensive tools on your farm.

  7. Housing conditions (hutches) and the environment

    For housing conditions, we used ambient temperature and relative humidity to calculate the temperature-humidity index (THI) within each hutch. As the environment, or outdoor weather, decreased by 1°F, the THI within the hutch decreased by 1.8 units. Note: this study did not consider wind speed. It is interesting to point out that the relationship between the environment and hutch THI is very strong.

  8. Housing conditions (hutches) and lying behavior

    As hutch THI decreased by one unit, calf lying behavior increased by about 2%. Note: small changes in lying behavior are not necessarily a bad thing, but if the THI gets low enough, it could greatly affect calf behavior. More lying behavior means calves are not as active, and possibly not eating or drinking as much.

  9. Housing conditions (hutches) and body temperature

    As hutch THI decreased by one unit, calf body temperatures decreased by 0.03°F. Note: The fluctuations in hutch THI can vary greatly throughout the day, potentially causing calf body temperatures to also fluctuate. These fluctuations challenge the calf’s immune system.

  10. Calf jacket tips

    The evidence of whether calf jackets work is not strong; however, if you have a positive experience with jackets, then I encourage you to continue using them. One thing to keep in mind is to check the jacket for sizing/fitting as the calf grows. It is a simple check that can make a world of difference. Many thanks to the American Jersey Cattle Association for providing monetary support for this project.

Bar graph showing number of treatments vs. calf age.
Figure 1. Example of the number of health treatments Jersey calves received during the first two weeks of life. The black bars represent calves with jackets and grey bars represent calves without jackets.

2019 Cooperative Dairy Students (CUDS) Reunion

This year will be the 41st year of the existence of Cooperative University Dairy Students or CUDS. The advisory team would like to invite to a celebration on Saturday January 26, 2019 at the Ensminger Pavilion on the WSU Pullman campus.

We are in the initial planning stages in regard to specific plans and will share more this fall.

Please reply and indicate your interest in attending, and also forward names and e-mail addresses for members that you know so that we can add them to our mailing list.


Joe Harrison, Amber Adams-Progar, and Amber Merk
CUD Advisors

Dairy Genomics Workshop

ashington State University and the University of Idaho are co-sponsoring a dairy genomics workshop in Prosser, WA on October 10, 2018, at the Walter Clore Wine & Culinary Center from 10 AM to 2:30 PM.

This meeting will bring together faculty from several universities to provide dairy farmers and advisors with the latest on genomic testing and research. More detailed information about the workshop and who to contact for registration ( can be found on the Veterinary Medicine Extension calendar. Lunch will be provided by Zoetis and Neogen.

Looking forward to seeing a lot of you there!

Dairy Farm Operations Manager, WSU Knott Dairy Center (Pullman, WA)

Would you like to be part of the heritage of producing quality milk for the world renowned Cougar Gold Cheese, and the distinguished Cooperative University Dairy Students (CUDS)?

The Department of Animal Sciences within the College of Agricultural, Human, and Natural Resource Sciences at Washington State University is seeking candidates for a Dairy Farm Operations Manager (Administrative Professional). The Dairy Farm Operations Manager is responsible for the management of the Department of Animal Sciences Dairy teaching and research herd (Knott Dairy Center). Duties include for planning, scheduling, and directing of personnel resources and facilities for the milking cow herd and replacement heifer events (calving, breeding, milking, nutrition and feeding, health care, forage utilization, milk and livestock sales. This position coordinates animal and facility use serves as the central person for communications and organizational issues in coordination of the needs of multiple research, extension, and courses. Additionally, the manager teaches classes and advises students as assigned by the department chair. The Dairy Farm Operations Manager is an important representative of the Department of Animal Sciences, WSU, and the dairy industry. Please see the full position description posting at for more information and to apply.

WSU is an EO/AA Educator and Employer.

June 2018 WSU Dairy Newsletter

2019 Cooperative Dairy Students (CUDS) Reunion

This year will be the 41st year of the existence of Cooperative University Dairy Students or CUDS. The advisory team would like to invite to a celebration on Saturday January 26, 2019 at the Ensminger Pavilion on the WSU Pullman campus.

We are in the initial planning stages in regard to specific plans and will share more this fall.

Please reply and indicate your interest in attending, and also forward names and e-mail addresses for members that you know so that we can add them to our mailing list.


Joe Harrison, Amber Adams-Progar, and Amber Merk
CUD Advisors

New Publication Tackles Approaches to Nutrient Recovery from Dairy Manure

Interested in learning more about emerging technologies for separating nutrients from dairy manure? WSU’s Center for Sustaining Agriculture and Natural Resources has a new publication that summarizes the various approaches being explored for nutrient recovery on dairies – and what we know about the current costs and performance that are associated with each strategy. The publication, Approaches to Nutrient Recovery from Dairy Manure, was a long term effort by Craig Frear (formerly of WSU CSANR), Jingwei Ma (a WSU graduate student), and Georgine Yorgey (WSU CSANR). This publication is a companion to The Rationale for Recovery of Phosphorus and Nitrogen from Dairy Manure.

WSU’s Center for Sustaining Agriculture and Natural Resources has worked on various aspects of anaerobic digestion and nutrient recovery for a number of years. Please visit our Anaerobic Digestion topic page for additional publications, videos, and resources, including links to our Anaerobic Digestion Systems Extension Publication Series.

Hoof Care: Beware Too Much of a Good Thing

Hoard’s Dairyman hosted a webinar called “Supervise Hoof Health with a No Lameness Tolerance Policy” on June 11, 2018. The presenter was Karl Burgi, professor emeritus at the University of Wisconsin-Madison School of Veterinary Medicine and Program Director at the Dairyland Hoof Care Institute, Inc. This article will be a synopsis of the portion of that webinar related to hoof trimming; readers are encouraged to view the entire archived webinar at Photos used here are from that webinar and used with permission.

Rates of lameness in cows producing over 90# milk/day on U.S. dairies ranges from 13.2 to 54.8%, with a mean of 25%. This huge variation is due to differences in management and factors affecting cow comfort on different farms, of course, but also attitudes about lameness. Some managers react to individual lameness cases; others recognize the effects of lameness on production and animal comfort and devote resources to prevention measures.

A 2017 study calculated the per-case cost of lameness at $527 per cow, which also includes pro-rated death and culling losses. A study of digital dermatitis (DD, a.k.a. hairy heel warts) in heifers revealed affected animals averaged 750 fewer pounds of milk over their first lactation and were open 28 more days than unaffected heifers. Lameness is also responsible for a 20% increase in premature culling and 2% death rate.

Lameness in early lactation is particularly costly because it affects peak lactation and lactation curves. Plus, if a cow becomes lame, the risk of recurrence is increased in subsequent lactations. This is because lameness and its predisposing factors can cause permanent changes to the skin, fat pad, ligaments, and bones of the foot. Therefore, a lameness management program should emphasize prevention for greatest success.

Lameness can be assessed on dairies by hoof lesion scores, locomotion scores (3-, 4-, and 5-point scale systems are available), management software, and/or hoof health analysis. The main foot lesions are DD, sole ulcers, white line disease, thin soles/toe ulcers, and foot rot. If DD is reduced, all other types of lesions will be reduced as well. The presentation includes recommendations for DD treatment and control not discussed here.

There are two types of hoof trimming: functional (routine to deal with hoof growth and maintain proper weight-bearing angles and surfaces) and therapeutic (treatment of issues causing lameness). Mr. Burgi states when it comes to functional trimming, “less is more” but “more is better” for therapeutic trimming. Ironically, hoof trimming may be a causative lameness factor if lameness cases persist in spite of addressing the following issues successfully:

  1. Cows are handled properly by crowd gates and humans (i.e., not rushed).
  2. Cow comfort is addressed and cows spend at least 12 hours lying down daily.
  3. Effective hoof baths are installed, used, and maintained properly (see webinar).
  4. Cows have secure footing on floors.
  5. Heat abatement measures are taken when needed to encourage lying time.
  6. Cows spend less than 2.5 hours/day out of pens (3× milking).

For each animal, assess the need for hoof trimming 3 to 8 weeks pre-calving and 1 to 3 times during lactation, or more often depending on the environment and an animal’s history. Routinely check first-calf heifers by 4 months into lactation. Note problem animals requiring more frequent monitoring in a computer management or other record-keeping system.

Pastured springing heifers should be brought in from pasture about 2 months before calving to give them time to develop protective fat pads in their feet and adjust to concrete. Their feet should be examined and trimmed at this time. Springing heifers stand significantly more time than cows. Standing on overgrown or improperly trimmed hooves will result in inflammation, which can predispose heifers to sole ulcers and a shortened productive life. Inflammation appears as redness in the sole (Photos 1 and 4); redness also means there is no overlying protective sole in that area.

Hoof trimming should not cause lameness, reduce cow welfare, or prevent lame cows recovering from their initial problem. Hoof trimming mistakes include:

  1. Trimming hooves too short. Normal claws should be 3” long with about ¼” sole thickness.
  2. Over-trimming heels, which changes (lowers) the angle where toes meet the ground (Photo 1); sole ulcers and white line disease can result.
  3. Grinding or otherwise over-trimming claw walls (Photo 2). The wall is weight bearing; grinding removes the wall and permanent P3 (coffin bone) remodeling and loss will follow. Never remove the wall unless the animal is lame and the wall is involved—in such a case, apply a hoof block after trimming.
  4. The sole is ground down excessively (Photos 3 and 4). Less than ¼” sole thickness causes inflammation resulting in sole ulcers and lameness. Soles can be ground away during excessive hoof trimming or by harmful environmental conditions (coarse sand, poor grooving, and exposed cement aggregate).
  5. Leaving claws unbalanced.
  6. Sole is not left flat.
Cow hoof displaying over-trimming on the heel (left) vs a well trimmed hoof (right).
Photo 1. Left photo shows over-trimmed heels causing undesirable low angle at toe, which changed the angle of weight bearing (dashed black line). Right photo shows targeted trimming preserving heel depth, which maintained proper toe angle. This resulted in good weight bearing through the entire foot bone structure with even weight distribution throughout the claw. Note how sole was pared away on right claw to remove weight-bearing surface over an inflamed area (yellow arrow) so this area can heal, similar to applying a block to the good claw. The green arrow and line denote where pressure is born on the sole: concentrated on the left photo due to low toe angle, which predisposes to sole ulcer and lameness; well distributed over the entire sole on the right.
Cow hoof displaying excessive trimming to the claw walls.
Photo 2. A “pretty hoof” post-trimming, but excessive wall was needlessly ground away, reducing the proper and normal weight-bearing tissue for this animal.
Cow hoof displaying excessive removal across the entire hoof, bleeding at toe.
Photo 3. Another “pretty foot” post-trimming where too much emphasis was placed on making a level weight-bearing surface. Note results of excessive grinding: so much protective sole has been removed that blood was drawn at toe; in that area, human interference has remove all the sole. A toe ulcer and lameness will follow. Weight-bearing wall tissue was also ground away needlessly.

Inflammation occurs before lameness. Some factors increasing the risk of inflammation include:

  • Calving—stressful time for all cows and heifers; any pre-calving foot issues are exacerbated after calving
  • Excessive standing—reduces hoof circulation, which affects hoof health; secondary to overcrowding, too much time in head catches or holding pens, heat stress, or uncomfortable beds
  • Delayed treatment—lets DD become chronic, facilitates secondary ulcers and foot rot
  • Lack of trimming—causes trauma from abnormal forces on hoof structures
  • Improper trimming—removes protective tissues, damages healthy tissues, leaves imbalance causing abnormal weight-bearing forces
  • Lack of blocking of ulcers—affected tissues do not have time to heal and inflammation continues. Blocks take pressure off painful tissues and increase oxygen contact with hoof tissues, which can kill some hoof disease bacteria.

Hoof inflammation can be prevented or reduced by providing an adequate number of comfortable stalls; using heat abatement measures to keep cows comfortable while lying; investigating all lameness cases within 24 hours; and using anti-inflammatory medications based on veterinary recommendations. Also, hooves should be trimmed 3 to 8 weeks before calving so all close-up animals have proper hoof anatomy and function. Close-up and fresh cows should have excellent cow comfort, including no overcrowding. Lameness in close-up, calving, and fresh animals should be avoided at all costs due to the major negative effects on milk production and animal welfare.

Cow hooves show displaying ulcers in the toe area.
Photo 4. Toe ulcers secondary to thin soles. Thin soles are caused by over-trimming (especially grinding), rough floors, coarse sand, and too much time standing.

Due to their associated costs, long-term implications, and effects on animal well-being, lameness cases need to be investigated and addressed promptly. Few conditions causing lameness improve on their own and many can progress to career-ending ulcers, abscesses, or bone/joint infections in otherwise productive cows. Having a well-defined lameness program with designated trained people responsible for lameness detection and prompt treatment is essential, as is a record-keeping system to flag and record actions.