Eliminating the effects of footrot on sheep flocks in the Northeast

Final Report for LNE10-294

Project Type: Research and Education
Funds awarded in 2010: $184,760.00
Projected End Date: 12/31/2014
Region: Northeast
State: Maine
Project Leader:
Dr. Richard Brzozowski
University of Maine Cooperative Extension
Expand All

Project Information

Summary:

Foot rot in sheep was studied over a four-year period in an effort to eliminate the disease from flocks and in anticipation of identifying genetic resistance to the disease. The research team developed a 4-week protocol for implementation in flocks having signs and symptoms of lameness. The team and participating farmers actively implemented this protocol which included inspection, trimming, evaluation, segregation of sheep groups and weekly foot bathing. Twenty-two sheep farms in the northeast participated in this applied research project by providing their sheep for evaluation via farm visits. These farmers worked along side the research team in handling the sheep, trimming feet and recording scores. Nearly 1,300 sheep were handled and evaluated over the life of the project.

In addition to the protocol, blood was sampled from each sheep and sent with individual foot scores to an Agricultural Research Service laboratory in Pullman, Washington for analysis in an effort to possibly identify a genetic marker for sheep showing resistance and/or susceptibility to the disease.

Participating farmers were surveyed each year to determine foot health conditions in their respective flocks. Results from an end-of-project survey of these farms in December 2014 showed that the protocol was effective in over 61% of the flocks and possibly up to 77% of the flocks.

Resistance and/or susceptibility to foot rot appears to be genetically controlled in sheep based on evidence of differences among breeds for resistance versus susceptibility, the ability to genetically select for resistance to foot rot, and a reported association between the incidence of foot rot and variation in MHC class II genes.

Initial genotypying was completed on approximately 240 animals using the Ovine SNP50 marker set that includes over 50,000+ single nucleotide markers. The results appear promising for additional genotyping and further genetic analysis. A more refined analysis is needed to determine a possible marker.

Over the life of the project, materials were developed and presentations made to equip producers with knowledge and skills in addressing foot rot in their flocks. An on-line template for producers to design their own written biosecurity plan for disease prevention was initiated.   To date, over 150 farms have used this tool. Informational items from the project web site have been used as a means to educate producers as well as agriculture service providers. Since its establishment, the project web site has received over 14,000 page views. The video on how to trim the feet of sheep received over 53,800 views. In addition, a 2-session webinar series on small ruminant foot health reached 36 and 33 individuals in the live broadcasts. Records for the archived webinar sessions show that Session 1 was viewed over 900 times and Session 2 was viewed nearly 250 times.

Introduction:

Sheep can be an important enterprise on farms in the northeastern United States as the region is the home of millions of people who consume lamb. However, significant barriers exist to the profitability of sheep including key animal health issues. Foot rot and the expenses related to it have been identified as one main reason sheep farmers are forced out of business. Foot rot is a highly contagious disease that requires relentless treatment using persistent hoof trimming, foot bathing, targeted treatments and other management practices such as isolation and special care.  These inputs require considerable time and money. In addition, hidden costs of the disease in losses of flock productivity related to breeding, grazing and growth can be significant.

An experienced research team comprised of a veterinarian, a biologist, a geneticist and two Extension small ruminant specialists led this project.  They addressed the disease by educating producers about the causes, treatment, management practices and preventative techniques including the use of genetic selection to work toward foot rot-free flocks.

Because a farm biosecurity plan can be an important tool in disease prevention, participating farms were highly encouraged to design, write and implement a customized biosecurity plan.

Over the four-year life of the project, a total of twenty-two producers from the region were selected by application to actively participate in this foot rot management program.  These producers were informed of sound biosecurity measures and trained in the techniques for hoof trimming, assessment, scoring and record keeping of foot health as a basis for culling poor-doers and for selecting breeding stock.  With the assistance of these producers, the team evaluated the feet and collected blood samples from nearly 1,300 sheep from participating farms.  These farms had sheep that showed signs of foot rot or lameness. DNA from the blood samples of all sheep was evaluated for predictive markers of foot rot resistance/susceptibility. This integrated approach of foot management and selection for resistance allowed sheep breeders the opportunity to work toward eliminating foot rot in the near future.  It was deduced that selection for resistance to the disease would reduce costs related to foot rot and would make producers less dependent on antibiotics and other inputs.

Performance Target:

150 participating producers will reduce losses in their sheep operation caused by foot rot by at least 70% and have a defined plan to develop a foot rot-free flock. It is estimated that producers spend from $1,600.00 to $2,000.00 annually addressing foot health in their respective flocks. A 70% reduction in losses for 150 producers is calculated to be $270,000.00 ($1,800.00 X 150 producers). A 70% reduction in losses related to foot rot for just half of the shepherds in milestone #1 is calculated to be $1,350,000.00 ($1,800.00 X 750 producers).

Cooperators

Click linked name(s) to expand
  • Dr. Anne Lichtenwalner
  • Dr. Charles Parker
  • Susan Schoenian
  • Dr. Thomas Settlemire

Research

Materials and methods:

As the applied research project was launched in 2010, a news story about the project was distributed to sheep associations in all 12 states that make up the Northeast region. It was also sent to the American Sheep Industry Association for publication in their weekly Sheep Industry email newsletter. The news story briefly explained the project and called for sheep producers to apply to participate. A project web site was established at which producers and others could learn more about the applied research project. Producers who had sheep that showed signs of foot rot or lameness as well as healthy sheep that had been exposed to foot rot but were not showing signs were encouraged to apply.

Applications from 3 farms were selected for participation in 2010. Over the following years, 19 more farms were selected to participate.

In the summer of 2010, the research team met on the first sheep farm to develop an effective protocol to eliminate foot rot. The team implemented that protocol as a trial basis on that farm over a 3-day period handling over 70 sheep of which many had foot rot. The sheep producer had significant input in the development of the protocol. As a part of the protocol, a method for evaluating feet was developed. A score sheet was designed to record scores for each foot of every sheep handled. Initially scores ranged from 1 to 5 with a score of 1 being a non-infected foot. Scores above 1 signified varying degrees of infection. After using this scoring method on the first farms, it became clear that a more defined method was necessary. There were too many choices and consistency in scoring became an issue.   Over time the scoring method was changed to a scale of 1 to 3. A score of 1 designated a non-infected foot. A score of 3 designated an infected foot. And a score of 2 designated uncertainty. In addition to the foot score for each sheep, the sex, age (lamb, yearling or aged), breed, hoof color and FAMACHA score were recorded.

Over a four-week period, the protocol combined careful and detailed hoof trimming, hoof scoring, weekly zinc sulfate footbaths, a hoof dry-time procedure, group segregation and putting animals onto clean pastures or areas where the foot rot causing organism was not present. This protocol did not include the use of antibiotics. It is best implemented after weaning for ease of lamb/ewe separation and when air temperatures are above 45 degrees F. This procedure was designed to optimize cure where a cure was possible as well as the identification of individual carriers which must be culled if a flock was to truly become free of foot rot. The cycle of infection had to be broken.

Because virulent foot rot is a contagious disease, it is imperative that the protocol be followed for effectiveness. Any gaps in following the protocol could result in failure and continuance of foot rot in the flock.

For the protocol to be fully effective, all animals in the flock must be included. If goats were present on the farm, they too must be included in the protocol as the same bacteria causing foot rot affects both sheep and goats.

The research team typically made visits to participating farms on Day 0 and Day 28. In some instances due to scheduling, a visit was made only on Day 0. Blood was drawn into test tubes from every sheep handled on Day 0 or Day 28 depending on the availability of a skilled person to draw blood from the sheep. Each test tube of blood was labeled with the individual sheep’s ear tag number and kept cool while in storage. Information on the record sheets and test tubes was cross-checked for accuracy. The blood samples were then packed with dry ice and shipped with foot score records to the USDA Agriculture Research Station (ARS) in Pullman, Washington for genetic processing. DNA from these samples was evaluated for predictive markers of foot rot resistance. 

The team worked with two sheep genome experts, Dr. Noelle Cockett and Dr. Stephen White, who are based in Utah and Washington state respectively.   Initial genotypying was completed on over 150 animals using the Ovine SNP50 marker set that includes over 50,000+ single nucleotide markers. Analysis continues and the results appear promising for additional genotyping and a more refined genetic analysis.

Following is an outline of the 28-day protocol designed to eliminate foot rot from sheep farms.

Day 0 (First Day)

All animals in the flock must be included in this protocol to be effective. The farm will provide an efficient handling set up or facility where the flock can be confined (panels, gates, working chute) which will allow individual animals to be easily caught and where each animal can be examined, feet trimmed and each foot scored.   If flipping sheep for trimming feet is physically difficult, a tilt-table is very useful. The tilt-table should be positioned as a part of the in-line chute movement of sheep. A tilt-table allows for better visibility of all feet resulting in better inspection of each hoof. A tilt-table also allows for more than one person to be safely trimming hooves at the same time. Proper foot trimming is a key to thorough inspection of each hoof, special treatment if necessary and healthy feet of each sheep handled.

As each animal is trimmed, each hoof will be scored to indicate a healthy foot, a foot that is infected or one that has structural abnormalities. When trimming feet, the foot shears and knives must be dipped in a disinfectant between the handling of each foot.  This dipping reduces the risks of spreading disease via the tools.

For simple scoring, use the numbers 1, 2 or 3 in scoring each foot of each sheep.

  1. A score of 1 is a “clean hoof” showing no signs of infection or inflammation. If a sheep has scores of 1 on all four feet, the sheep should be marked accordingly and moved to the foot bath (10% zinc sulfate solution) and allowed to stand in the bath for at least 5 minutes. After being released from the foot bath, these sheep must be held in a separate group pen or released to an area that has held no sheep for at least two weeks.   In the coming weeks, the sheep in this clean group should be handled first, observed and sent through the foot bath before any other sheep. These animals should never be placed in pens or on ground that have had infected sheep/goats or uncertain sheep/goats for the past 2 weeks.
  2. A score of 2 on a foot designates uncertainty. No rot is evident by sight or smell of these feet but signs or symptoms of inflammation, swelling, lameness or soreness might be detected. Sheep with any foot with a score of 2 should be marked accordingly and moved to the foot bath (10% zinc sulfate solution) and allowed to stand in the bath for at least 5 minutes. These sheep must be segregated into a group pen with other uncertain sheep. This grouping is a precautionary measure.       These sheep will receive treatment over the next 4 weeks. In the coming weeks, the sheep in this uncertain group follows in sequence behind the clean group. Keep these sheep in their group until Day 14 or Day 21, when if designated “clean” at that time can be placed with the clean, non-infected group. Do not move them to the clean group until absolutely certain. Be meticulous in scoring these sheep.
  3. Any hoof that has rotting tissue on any part of the hoof is scored as a 3. There will be a putrid smell to the feet of sheep with foot rot. All sheep with any foot with a score of 3 should be isolated from sheep with scores of 1 or 2. They should be marked accordingly and moved to the foot bath (10% zinc sulfate solution) and allowed to stand in the bath for at least 5 minutes. These sheep must be placed into a group pen with only sheep with scores of 3. It is strongly suggested that the producer consider culling any animal with a score of 3. If sheep from this group are not culled but are kept for treatment, the sheep in this infected group should follow in sequence the uncertain group for handling and foot bathing. Do not mix any infected sheep or uncertain sheep with sheep that are clean (not infected). If sheep never heal to 4 healthy hooves, they must be culled.       Some sheep are chronic carriers of the foot rot bacteria.

Immediately after trimming and before individual sheep are released to the foot bath, each foot was doused with a 20% zinc sulfate solution sprayed from a spray bottle.

The animals should then be directed to stand in a footbath tub. This tub or foot bathing area can be purchased from a manufacturer or constructed on the farm. The footbath should be sized to be included as part of a working chute. As an option, baths that are larger can be used where several animals at a time can be treated. An adequate supply of zinc sulfate powder and detergent must be obtained to make a 10% zinc sulfate solution (8.5# zinc sulfate/10 gallons of water + one cup detergent). It is best if old wool or pine shavings are available to place in the bottom of the footbath to create a “soaking pad” to reduce splashing and loss of zinc sulfate solution. Each sheep needs to stay in the bath for at least 5 minutes. After the footbath treatment, the sheep will be separated into (1) healthy, infection-free group or (2) placed into an uncertain or suspect/recovery group or (3) placed in an infected/recovery group. Sheep in each group should be color coded with a suitable livestock marker for quick identification by group. Sheep in the infected/recovery group are candidates for possible culling. These sorted sheep will be placed in designated “drying” areas (well-bedded barn area or dry, hard surface such as a clean concrete pad or clean wooden floor). The animals need to stay in the drying area for a minimum of 30 minutes.

Each group will then be moved to separate pastures or holding areas where sheep have not been for two weeks (the length of time the causative bacteria for foot rot can live outside contact with sheep).

By the end of the day on Day 0, each farm is encouraged to develop a written biosecurity plan as a preventative measure. Because foot rot is typically “purchased” or brought to the farm unintentionally, a biosecurity plan can be effective in keeping the disease off the farm. A biosecurity plan should include objectives for identifying procedures to protect the flock from disease that may be brought to the farm by newly introduced animals, visitors, equipment and other means.

An online template for writing a biosecurity plan was developed by two team members with the help of an Information Technology specialist. This template can be found at Maryland’s Small Ruminant web site www.sheepandgoat.com Producers log into a secure website and respond to a list of categorized questions. Upon completing the questions, the producer saves the document as the biosecurity plan for their farm. Their customized document can be printed and updated as needed.

DAY 7

  1. Sheep are moved by groups in the proper sequence. Group 1 (sheep with non-infected feet) is always handled first. Group 2 (sheep that the scorer is uncertain regarding the health of the sheep’s feet) is always handled second. Sheep from Group 3 (sheep showing signs of infected feet) is always handled last. This sequence reduces the risk of reinfection of individuals.
  2. Each sheep will be treated in a footbath/drying protocol.
  3. All sheep should be carefully observed and any sheep in the Healthy Feet Group that is limping will be inspected and if any infection is found, feet trimmed if necessary and moved to the infected group (comprised of sheep with any foot with a score of 3).

DAY 14

  1. Sheep are moved by groups in the proper sequence. Group 1 (sheep with non-infected feet) is always handled first. Group 2 (sheep that the scorer is uncertain regarding the health of the sheep’s feet) is always handled second. Sheep from Group 3 (sheep showing signs of infected feet) is always handled last. This sequence reduces the risk of reinfection of individuals.
  2. All sheep will be confined and each hoof scored and recorded by the sheep producer. The handler should check all feet and trim hooves if needed. Animals in the Uncertain Group (Group 2) or Infected/Recovery Group (Group 3) who have healed and show no signs of infection or foot abnormality can be moved to Healthy Feet Group (Group 1). Likewise, any sheep in the Healthy Group that show any infection or suspicious feet will be moved to the Uncertain Group or Recovery Group depending on the feet scores.
  3. Immediately after trimming and before individual sheep are released to the foot bath, each foot was doused with a 20% zinc sulfate solution sprayed from a spray bottle.
  4. All sheep will be treated using the 10% zinc sulfate footbath/drying protocol.
  5. Each group will be moved to separate pastures or areas where no sheep have been for the past 2 weeks.

DAY 21

  1. All sheep will be treated in the footbath and drying protocol described above, following the proper sequence of groups (1, then 2, then 3).  This sequence reduces the risk of reinfection of individuals.
  2. All sheep will be observed and any limpers in the Healthy Group will be checked and if any infection found, trim if necessary and moved to the Infected/Recovery Group (Group 3).

DAY 28

  1. Sheep are moved by groups in the proper sequence. Group 1 (sheep with non-infected feet) is always handled first. Group 2 (sheep that the scorer is uncertain regarding the health of the sheep’s feet) is always handled second. Sheep from Group 3 (sheep showing signs of infected feet) is always handled last. This sequence reduces the risk of reinfection of individuals.

  1. Inspect all sheep, trim feet if necessary, score each hoof. Immediately after trimming and before individual sheep are released to the foot bath, each foot was doused with a 20% zinc sulfate solution sprayed from a spray bottle.

  1. Treat all animals in the 10% zinc sulfate footbath/dry area protocol as described above.

At the end of 4 weeks (28 days), the combination of proper trimming, zinc sulfate foot bathing treatment and use of clean pastures should have allowed enough time for all sheep, with the possible exception of carriers, to heal. All animals that had not healed and animals classified, as carriers should be culled from the flock. The decision to cull individual sheep is strictly up to the respective producer or owner. However, the culling option should be explained to each participant so that they recognize how important culling is in establishing and maintaining a flock free of foot rot.

Research results and discussion:

Milestone 1. 1,500 producers in the northeast will learn about the applied science of foot health of sheep and its influence on the profitability of their enterprise. They will gain skills and knowledge in current methods used to effectively treat and prevent infectious foot diseases as well as to identify genetically tolerant individuals. This will be accomplished in the first year by some producers but may also be accomplished by others in years two three and four.

This milestone was accomplished through the following outreach methods. Our web analytical records show that the project website reached 14,105 pageviews. In addition, 53, 881 people viewed the sheep feet trimming video. The 2-session webinar series on small ruminant foot health reached 36 and 33 individuals in the live broadcasts. Our records for the archived webinar sessions show that Session 1 was viewed 910 times and Session 2 was viewed 247 times. That part of the project web page titled http://umaine.edu/sheep/foot-rot/ has received 2,238 pageviews; 284 individuals viewed and likely completed the sheep foot rot quiz that was posted on the project web site.

Milestone 2. At least 500 sheep producers in the region will develop and implement a customized, written biosecurity plan for their operation. This goal will be accomplished in the first, second and third years as producers recognize the value of a written biosecurity plan.

This milestone was partially reached through the implementation of an online biosecurity plan template developed by two team members with the assistance of an Information Technology (IT) specialist. Our records for the first version of the template show that 151 producers completed a written biosecurity plan. A revision of the first template occurred in December 2014. In addition, the number of visits to the project web site as of December 2014 for biosecurity information for “preventing foot rot” was 320 pageviews. The number of visits at the project web site for and article explaining “biosecurity for your flock” was 462 pageviews. Through verification methods used, this milestone was not quite fully accomplished.

Milestone 3.  In year one, 20 sheep producers will be selected by application. These farms will be visited by research team members to train the producers with the knowledge and skills to evaluate, score and record foot health. From these participating flocks, a total of at least 300 sheep will be tissue sampled to test the efficacy of genetic markers for resistance to foot rot infection.

This milestone was not fully accomplished in year one as expected. However as each year passed for the project, sheep producers from across the northeast region submitted applications to participate. Logistically it would have been difficult to handle 20 applicants in one year. As a result, we received applications and scheduled farm visits from 3 to 10 individual farms each year. It was determined that the only time to effectively detect and address foot rot with the foot bathing protocol was when air temperatures were over 45 degrees F because that is the point at which the bacteria causing the disease was typically evident and able to spread. A total of 22 farms in the northeast participated in the project. Visits to participating farms took place in the months from May to early November.   As a part of the protocol, blood was sampled from nearly 1,300 sheep over the life of the research project and sent to an Agricultural Research Service lab in Washington state for processing. The number of pageviews as of December 2014 for applying to the project http://umaine.edu/sheep/apply/ was 1,208.

Milestone 4.  In year one, an advisory team for this research project will be established that will include at least 5 sheep producers from participating farms as well as the research team members.

No formal advisory team was ever established for the project. Instead the Principal Investigator worked closely with participating farms and the members of the research team in addressing issues, obtaining feedback and planning next steps on a regular basis. An electronic survey was emailed at the end of each year to gather feedback from the current group of participating farms. By the end of the project, twenty-two farmers were asked to provide feedback. In addition, conference call phone conversations with the 5-member research team were used to discuss the project, address problems and make decisions. The team also involved two sheep genome experts from outside the region for advice and direction.

Milestone 5.  At least 150 shepherds in selected states will develop and maintain a detailed foot rot control program for their operation. This management program would include the use of preventative techniques as well as to identify individual sheep that genetically are tolerant to foot rot. The overall goal would be for each producer to develop a foot rot resistant flock with value-added seed stock for sale. This goal will be accomplished by the third year.

By the end of the project, this milestone was accomplished through the adoption of the foot rot elimination protocol and the use of the on-line biosecurity template developed by research team. The team expected that producers with lameness or foot problems in their flocks would adopt the protocol for their own use. Through an on-line template for writing a customized farm biosecurity plan, 151 farmers now have a defined plan for a foot rot-free flock. Of the participating 18 farmers who responded to the end-of-project survey, 61.11% said their flocks were foot rot free. The percentage of participating farmers who were not sure if foot rot persisted in their flocks was 16.67%. The percentage of those producers who still had foot rot in their flocks was 22.22%. No further measurement of this milestone for farms other than those farms participating in the project was performed.

Participation Summary

Education

Educational approach:

The following resources – project web site, publications and outreach activities related to this research project were published, under review or presented.

“Sheep Foot Health Research & Education” is the project web site at which information related to this applied research project and foot rot is posted http://umaine.edu/sheep/

“The sheep foot health protocol” – This checklist outlines the step-by-step procedure designed for sheep producers to address animal foot rot and lameness on their farm in an effort to eliminate foot rot over a 4-week period.

“Setting up to inspect and trim sheep feet” – This publication outlines the considerations for sheep producers to set up their facility to efficiently and safely inspect and trim sheep feet.

“Tips for detecting disease and injury in sheep and goats” – This checklist presents what to look for in determining normal and abnormal animals in their flocks and herds by sheep and goat producers.

“Foot Rot – Test Your Knowledge of Sheep and Goat Hoof Care and Diseases” – This on-line, multiple choice, self correcting quiz developed by research team member, Susan Schoenian, is designed to help sheep and goat producers better understand and address foot rot. http://umaine.edu/sheep/foot-rot/quiz/

“Written Biosecurity Plan Template” – This on-line template is designed for sheep and goat producers to respond to a set of questions with the resulting document being a customized biosecurity plan for their farm. http://www.sheepandgoat.com/biosecurity/

“Risks of Disease Transmission – Safe Shearing” – This revised publication outlines how sheep producers and sheep shearers in the detection and prevention of diseases that could be inadvertently spread by the sheep shearer.

“Hoof Health and Management” – A webinar series comprised of two, 60-minute webinars by research team members Susan Schoenian and Richard Brzozowski presented February 20 and 27, 2012. Thirty-six and thirty-three individuals participated in the live broadcasts of the webinar sessions respectively. Many more viewed the archived sessions.

“SARE Funded Programs” a presentation included particular information about this research project by Principal Investigator, Richard Brzozowski, for the Northeast SARE Administrative Council, February 2012 in Burlington, Vermont

“Identification of Genetic Regions Influencing Footrot in Sheep” a presentation made by Dr. Stephen White, at the Plant & Animal Genome XXI Conference January 14, 2103 in San Diego, California.

“Footrot in Sheep: Applying an Antibiotic-Free Approach” a presentation made by research team member, Dr. Anne Lichtenwalner DVM, PhD at the Missouri Livestock Symposium on December 6, 2014 in Kirksville, Missouri. Thirty (30) people attended this presentation.  

“The Sheep Foot Health Research Project – Northeast SARE Project Report” a presentation by PI Richard Brzozowski at to 25 agriculture service providers on November 25, 2013 in Orono, Maine

“The Sheep Foot Health Research Project” a presentation by Principal Investigator, Richard Brzozowski to 18 Extension colleagues on November 21, 2014 in Bangor, Maine

“The Sheep Foot Health Research Project” a presentation by Principal Investigator, Richard Brzozowski to 30 sheep producers at the 2014 Annual meeting of the Maine Sheep Breeders Association on November 15, 2014 in Fairfield, Maine

Additional Project Outcomes

Project outcomes:

Impacts of Results/Outcomes

150 participating producers will reduce losses in their sheep operation caused by foot rot by at least 70% and have a defined plan to develop a foot rot-free flock. It is estimated that producers spend from $1,600.00 to $2,000.00 annually addressing foot health in their respective flocks. A 70% reduction in losses for 150 producers is calculated to be $270,000.00 ($1,800.00 X 150 producers). A 70% reduction in losses related to foot rot for just half of the shepherds in milestone #1 is calculated to be $1,350,000.00 ($1,800.00 X 750 producers).

It is evident that most of the sheep producers actively involved in this project reduced monetary losses to their respective sheep enterprises caused by foot rot. Although no exact measurement of losses was quantified, estimations reported by participating farms showed an average of $885/farm/year in savings after implementation of the foot rot elimination protocol. Foot care of sheep is a management practice that has a cost even in healthy flocks. If foot rot disease or causes of other lameness are present in a flock, the cost to treat it as well as the hidden costs of lost productivity of the flock can be great – sometimes too great to withstand for the farm business. This project provided the opportunity for sheep producers to detect, correct and prevent situations related to sheep lameness that made a positive difference to their bottom line. Through an on-line template for writing a customized farm biosecurity plan, 151 farmers now have a defined plan for a foot rot-free flock. Based on the number of producers who used the project web site and interacted with the research team, it can be deduced that this performance target was met.

An important aspect of this research project was the work toward the possibility of identifying a genetic marker for resistance to the disease. As an initial step in the identification of genetic regions that influence foot rot in sheep, genotypes for the Ovine SNP50 BeadChip were obtained for 87 animals from four flocks, of which 27 animals had evidence of classic foot rot with necrotic tissue in at least one hoof, 29 had intermediate foot rot scores with some inflammation and/or discoloration (possibly early or resolving positives), and 31 were negative based on the absence of infection/inflammation in all four hooves. Case-control matching accounted for farm, breed (Merino or Katahdin), sex, and an age category (lamb, yearling or adult).  Linear regression analysis of disease score was performed using PLINK with a genome-wide significance threshold of 5×10-8. Initial analyses revealed a genome-wide significant SNP on ovine chromosome 18 (P=3.6×10-8). Ongoing analyses include a search for candidate genes in this genetic region of the emerging sheep genome assembly and additional association testing with larger animal sets.

Economic Analysis

When asked in an end-of-project electronic survey, “Did your participation in the proejct have an economic impact on your flock because of any changes you have made?”  Consider any savings in labor, medications, veterinary expenses, sheep performance, sheep productivity, etc.  Please mark the option listed below that best refelcts your situation.  Fifteen of the twenty-two participating farms responded as follows:

Five producers (of the fifteen responding) selected the option “There was no economic impact.”

Two producers (of the fifteen responding) selected the option “On average, I estimate that I save less than $500 a year as result of the changes I have made”.

Three producers (of the fifteen responding) selected the option “On average, I estimate that I saved between $500-$1,000 a year as result of the changes I have made.”

Four producers (of the fifteen responding) selected the option “On average, I estimate that I saved between $1,000 and $2,000 a year as result of the changes I have made.”

One producer (of the fifteen responding) selected the option “On average, I estimate that I saved over $5,000 a year as result of the changes I have made.”

Additional comments related to the economic impact by nine of the fifteen participating farmers to this question were as follows:

There was a net loss, albeit short term, following our participation as a result of culling nearly 25% of the flock. The loss was most damaging in terms of loss of genetic progress estimated at a 4 to 5 year setback in improvement.

This savings is based on 2 whole flock foot inspections/trimmings and 5 individual animal treatments/trimming.

Most of this savings is reflected in labor savings and medication. There is really not a price set on the overall well being of my sheep, but it matters very much to me.

Difficult to put an exact value on it. It was either fix the problem or get out of sheep.

Tremendous labor saving by eliminating hoof problems

Veterinary bills and my time spent treating

Actually cost money. Had a metal bath fabricated, and it takes more time, but the handling is appropriate as I do FAMACHA at the same time, and can keep a closer eye on the young stock. But then I really did not have much of a problem in the first place. It has made my breeding stock more valuable when I sell them, so I have increased my gross income.

Difficult to estimate. We now use the time previously spent in foot trimming for other things–pasture improvement, marketing. Financially, it is a boon. It is difficult to market lamb and yarn when the animals are limping in front of visitors. That we care about people infecting the sheep makes everyone aware that we are careful farmers.

We do not have hired help. Our savings has been reflected in the amount of our time required to related to foot problems. Our quality of health has clearly been enhanced by being able to spend time on other productive activities.

It was extrapolated from these responses that on average, each producer saved approximately $885/year by following the protocol in addressing foot rot.

Farmer Adoption

The following informational materials related to this project were posted by research team member Small Ruminant Specialist, Susan Schoenian on the Maryland Small Ruminant web page www.sheepandgoat.com and used by interested individuals. Below is a brief analysis of views and downloads for each.

Hoof health and management handout – 1,593 views, 62 downloads
Sheep foot health and management PowerPoint presentation – 3,778 views, 194 downloads
Goat foot health and management PowerPoint presentation – 6,470 views, 115 downloads
Sheep foot health and management handout – 2,186 views, 37 downloads
Goat foot health and management handout – 2,343 views, 54 downloads

When asked in an end-of-project electronic survey, “How did participating in the sheep foot health applied research project affect the health and productivity of the sheep in your flock?”, 18 of the 22 participating farmers in this project responded (including both positive and negative comments) as follows:

Our farm benefited from this project in two ways. Our ability to diagnose and treat was greatly enhanced and our ability to identify animals with chronic issues was developed.

It taught us to pay a lot more attention to their hoofs and taught us how to properly take care of them.

It helped and did cut down on the incidence of foot rot.

No sheep are currently limping, nor have any sheep shown signs of foot rot this year. Before starting the study more than half the flock was limping, many so severely affected that they had to graze on their knees.

It provided data about my sheep’s foot condition. The specificity allowed us to try remedies.

Prior to the project foot rot had become more problematic in the flock despite “control” measures. We were considering disbanding the flock. Participation in the project allowed us to eradicate the foot rot and maintain a clean flock that is now expanding.

I learned more about foot rot, foot scald and hoof trimming than I had known before participating.

My participation taught me how to manage the problem in a way that eradicated it. My sheep are much healthier for it.

It was immensely helpful. For a period of time, we had no problems. Then we changed managers, and the problems recurred. Clearly there is a managerial component to our recidivism, and what would be helpful would be a video summarizing best management practices, a clear demonstration of what to look for, and what continuing efforts must be maintained. For those of us who own farms but are not involved in daily management, this would be a great training tool.

I think it helped us because now we pay close attention to them to make sure that they do not have hoof rot and that they have healthy feet.

I believe it helped the overall foot health of my flock.

GREAT to have support, and fresh eyes on both my management techniques, successes and failures. So I guess it helped MY productivity, and made me feel more empowered, no so SHEEPISH. I have become much more diligent about keeping a boot bucket for visitors, and run them thru a bath more often, so their foot health is not something I worry about anymore. Got bigger problems, like coyotes!

We did a lot of culling, but we have not had foot rot (or scald) in 4 years in our flock. For the sheep that remained, they are healthier. We seem to have a slightly increased rate of twinning even though we lamb out of season.

The knowledge acquired from the research project has resulted in out putting greater focus to the foot health of our flock. We have a healthier flock. Sound sheep are more productive over a longer life.

Our sheep are more comfortable as a result of participating in the foot health study. We don’t have the hassle of treating foot rot in our flock. This means that we spend less time handling sheep which saves us a huge amount of time.

Participating in the project gave me tools/knowledge how to treat foot rot should my flock become infected.

Unfortunately, and I feel really bad saying this but we felt we had more problems with foot rot after the project than before.

When asked in a end-of-project electronic survey, “What did you learn as a result of participating in the sheep foot health applied research project? Include any management practices that you have initiated or have changed as a result of your participation.” 16 of the 22 participating farmers responded as follows:

I learned a lot. I learned how to really trim feet effectively even though I thought I knew how to before. I think my experience with the project opened my eyes to foot ailments as a whole and not just foot rot per se. Sheep limp for a lot of reasons and not always foot rot. Also, that there are numerous strains of the foot rot bacteria, some of which are more virile than others. We routinely soak in ZnSO4 after trimming feet, always in spring and sometimes in fall.

We now soak feet after we trim feet twice a year

How to recognize foot rot. How to treat for elimination of foot rot. How to run a bio-secure farm with all visitors cleaning shoes before and after walking onto the fields.

Attention to detail. – Usefulness of a comprehensive plan for eradication – Importance of culling – Importance of closed flock

We try to be more proactive with better routine foot care.

I am now aware of the biosecurity practices that need to be followed in order to have healthy sheep feet

We learned precisely what had to be done. What we didn’t learn was how to make the farm manager keep his team doing it! This cannot be taught, so the problem lies with us. We do keep much better records, we culled those animals we thought were a continuing problem, we trim hooves (though not as often as we should) and we do treat those who have scald or foot rot .

I learned that we did not pay close attention to our sheep and with this, we now look at them and if they look like they are getting hoof rot then we will bring them in and treat them.

Nothing beats aggressive culling.

Better biosecurity. More frequent foot bathing.

Clippers are not enough–a hoof knife is essential to get between the toes. Records are to be used and kept up as they’re a tool also. It’s easier to regularly clip feet when it’s routine clipping, not shaping deformed hooves from foot rot. We are careful about visitors to the farm as to keeping PEOPLE feet clean also.

We know what to look for and what our options are. We quickly pick up on any signs and take prompt action. We trim feet more frequently; at a bare minimum we trim at breeding time and at weaning. This has been made possible by setting up an inside chute with turning cradle. At the same time we quarantine any new arrivals on the farm.

How to trim hooves correctly – FAMACHA scoring – Foot bath recipe

When participating farmers were asked for additional comments, their responses (both positive and negative) are as follows:

Blood was taken during one of the visits and participants should be informed of the status of those samples whether they were ever used or not. This was actually our primary reason for participation but I don’t recall ever hearing an update on what happened. Not enough emphasis was paid to antibiotic treatment in addition to trimming and soaking. If there are some antibiotics that are known to be effective in at least some cases, this should have been coupled with the projects protocol. I don’t believe trimming and soaking alone is that effective in controlling foot rot or that the time frame of the protocol was adequate to determine if sheep were effectively foot rot free. Sadly, culling more than you probably need to, in my mind, remains the definitive option for foot rot control.   Although the outcome was not what we expected, we deeply appreciate all the hard work of the investigators, and we learned a tremendous amount about foot health in sheep.

This is a great project. It has changed both our thinking and our management of our flock around this issue.

Between trimming feet twice a year and the new Zactran®. I may have it licked.

The sheep foot health project has made the difference between us getting out of the sheep business and continuing and now growing the flock. All the investigators involved were most helpful and I value our ongoing relationship.

Thank you for including us.

THANK YOU! I couldn’t have done this without the project. I AM VERY GRATEFUL TO YOU. I would recommend these practices to anyone who is having these issues.

This project was very, very helpful, and I would like to see a demo CD that could be used for training new farm help/managers.

I am very grateful for the support of SARE and the folks who put this together. We need more focus on more growers and best management practices as we endeavor to restore a healthy small ruminant industry here in New England. This is a GREAT beginning!

I think the effort to go thru the foot rot procedure has made us more conscious of doing things in a systematic way. It has clearly pushed us to use a computer program to keep our records available –and to input the data routinely. Previously foot rot was the overriding concern and the biggest time input. Now foot trimming is merely routine and we are more invested in lambing, wool production, marketing.

Without this project, I suspect we would still be struggling with foot rot. We are very grateful for the opportunity to participate.

This project gave us many tools to keep our sheep healthy and productive.

The protocol has not eliminated the current problem….even after heavy culling.

Assessment of Project Approach and Areas of Further Study:

Areas needing additional study

In relation to foot rot and lameness in sheep, the following studies are suggested:

Continue to search for the gene that marks resistance to foot rot. Can you imagine the benefit if it was possible to genetically test for resistant animals to foot rot? We hope to use samples from 200+ sheep with known foot rot phenotypic information generated in the project to generate genotypes using the Illumina ovine High Density (700,000 single nucleotide polymorphism [SNP] per sheep) genotyping array. Earlier in the project, we had genotyped slightly less than 100 sheep with the Illumina OvineSNP50 array (50,000 SNP per sheep) and used these data to identify a promising genomic region associated with susceptibility to footrot in domestic sheep. The use of more sheep for validation and 10+fold more genotypes should enable us to confirm this genomic region and more finely map the location of the genetic variant(s) of interest. Furthermore, we will also use these data to search with increased power and mapping precision for additional genomic regions of interest related to sheep footrot susceptibility. Both of these uses for the genotypic data are concrete steps toward future development of genetic marker tools that may enable producers to selectively breed sheep with improved foot health.

Further study is needed to refine the protocol developed by this project in addressing foot rot on farms. For what reasons did the protocol fail to eliminate foot rot for 22% or more of the participating farms? What is the optimum duration of time for soaking feet in the foot bath? Is zinc sulfate the most effective material for foot bath? Is a 10% zinc sulfate foot bath the most effective proportion?  Safety and efficacy studies of different foot bath solutions and soaking durations are needed. 

There is need for a foot “bath” mix to be used in the winter when liquid mixes would freeze. Some work on a “dry mix” of lime mixed with zinc sulfate has ben tried. However, a systematic study is needed to compare with no treatment and maybe and another variable.

Research is needed to develop a robust phenotypic test for foot rot, such as further exploring keratin quality or some biomarker that can be quantified at point-of-sale. 

Applied research is needed in detecting degrees of pain in sheep with foot rot.

Economic studies are needed measuring the effects that foot rot can have on sheep enterprises.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.