Lameness and arthritis management were the subject of a webinar sponsored by the Swine Health Information Center (SHIC) and the American Association of Swine Veterinarians (AASV) on Oct. 13, 2020. Recordings of the webinar are available here.
In her presentation, Dr. Kathleen Wood of Christensen Farms said, in her experience, lameness is the number-one cause of mortality in pigs in the mid- to late-finishing stage. Understanding the causes, costs and management methods can help address consequences of lameness and arthritis, she said.
Wood was joined by nutritionist Dr. Paul Cline with Christensen Farms, practitioner Dr. Michael Eisenmenger with the Swine Vet Center and diagnosticians Dr. Michael Rahe with Iowa State University and Dr. Stephanie Rossow with the University of Minnesota.
As the latest in a series of webinars addressing swine industry chatter, SHIC said this event provided participants' experience, recommendations and direction for addressing these issues which have been on the rise, per submissions to veterinary diagnostic laboratories (VDLs). The webinar was conducted by Iowa State's Swine Medicine Education Center.
According to SHIC, Eisenmenger and Wood said solving the issue of lameness requires veterinarians to be in barns observing animals as well as performing necropsies to define the cause of lameness. Eisenmenger recommended combining resources to examine flow, health, nutrition and operations as causes of lameness and working together to identify issues. The best chance for success, he advised, is to work in a manner that increases the opportunity for answers when working with VDLs.
During her presentation, Wood said she had farms where 10-25% stiffness in grow/finish pigs grew to 25-40% this year, which she attributes to a variety of factors, including infectious arthritis, injury or trauma, as well as leg conformation problems or defects. Additionally, she suggested that some of the increase in incidence was due to heightened awareness of stiffness after a return to closer observation as barn visits resumed after a lag due to the COVID-19 pandemic.
Wood believes anti-inflammatory injectables are an important treatment, relieving pain and related issues, SHIC said. However, their use is variable and may be difficult to manage with potential issues revolving around withdrawal times for grow-finish pigs. She also recommended looking upstream for possible origin of stiffness/lameness problems, including sow nutrition, sow farm medications and pre-farrow vaccinations.
Critical to management is field communication. According to SHIC, Wood believes continual training of staff to recognize and properly identify issues is essential, working from the premise lameness and stiffness are not part of "normal." She also recommended more practitioner field time, necropsies and pursuing diagnostics. In fact, she said, "necropsy everything," including popping open joints, snapping ribs and broken bones identified during routine necropsies versus only in infection/abscess presence.
Cline shared a nutritionist's perspective during the webinar. He said the industry needs to do better at understanding the interactions between health and nutrition. One of the ways to deal with that is to nurture the agreement that veterinarians and nutritionists are working toward the same goal. He also believes a more robust standard reference resource for bone characteristics is necessary, SHIC said.
Cline discussed how the consequences of an out-of-feed event are not truly understood in terms of how quickly bone ash changes. Another area in need of examination involves components that need to be measured to understand the impact on bone. This includes boron levels in feed, impact of intake level on bone development as well as seasonality, SHIC said.
For getting the best results when seeking results from submissions to VDLs, Rahe offered these best practices:
- Submitters can call VDL ahead of time to discuss what is seen in affected pigs and what tissues would be helpful to submit.
- Live pigs or limbs can be submitted.
- Tissues to submit for lameness workup include:
- Joints to rule out infectious arthritis or submit limbs;
- Serum - vitamin D (collect antemortem or shortly after euthanasia);
- Second ribs (bone ash and density);
- Fixed long rib(s) - 10th ribs (microscopic evaluation of physis (growth plate) and trabecular and cortical bone);
- Fixed skeletal muscle from hamstrings, triceps and diaphragm;
- Fresh and fixed liver (vitamin E and trace mineral panel);
- Urine (calcium and phosphorus), and
- Fresh and fixed lung, kidney, spleen and brain to rule out systemic disease, meningitis, encephalitis, etc.
Rahe said acutely affected pigs are better than chronic pigs for sample submission and agent isolation. Sampled pigs should represent what is being observed in the herd. He also emphasized that findings/diagnosis in one pig could be an isolated case and not necessarily representative of the herd. Correspondingly, the same finding in multiple animals then adds confidence in a herd level diagnosis.
SHIC said Rossow began by emphasizing that structure of the pig is directly tied to function, so addressing lameness concerns is essential. She said abnormal structure equals abnormal function with related consequences affecting pig health and performance. Understanding disease initiators versus promoters also helps develop effective prevention and treatment protocols.
Rossow emphasized the importance of using a diagnostic lab, saying VDLs have the people, time and tools for extensive investigation.
Previous webinars in this series have covered viral myelitis, tracheitis and coccidiosis and can be viewed in the AASV Video Library. Ideas for future webinars are welcome; submit to SHIC executive director Dr. Paul Sundberg at firstname.lastname@example.org.
As the world deals with the COVID-19 pandemic, SHIC continues to focus efforts on prevention, preparedness and response to novel and emerging swine disease for the benefit of U.S. swine health. As a conduit of information and research, SHIC encourages sharing of its publications and research. Forward, reprint and quote SHIC material freely. SHIC is funded by America's pork producers to fulfill its mission to protect and enhance the health of the U.S. swine herd. For more information, visit www.swinehealth.org, or contact Sundberg at email@example.com.