Date Full Report Received08/03/2011
Date Abstract Report Received08/03/2011
Funded ByNational Pork Board
The main objectives of this study were: 1) To produce a robust observational lameness scoring system with accompanied visual educational material, (2) to assess sodium salicylate and flunixin meglumine (Banamine) for pain mitigation in sows with lameness and (3) to validate an objective measuring tool; the “crate adapted static force plate” (CASFP) as an objective assessment tool for sow lameness. Twenty four clinically normal sows were purchased from a Midwestern facility and acclimated to CASFP in the lab. Sows were temporarily made lame on one of four feet, and were randomly assigned to one of two analgesic treatment groups (NSAIDS) or a control treatment. Forty-eight hours after lameness was induced NSAID treatments were initiated and were given daily for four consecutive days. CASFP and lameness scores were recorded on the day before sows were lame (Day -1: when they should have been clinically sound), the day after they were made lame (Day +1: when they should have been most lame), and the last day of the treatment regimen (Day +6: when they should have the most benefit from the treatment). Lameness was assessed both subjectively and objectively. Lameness scoring systems are designed to categorize the degree of lameness typically expressed during locomotion. There are two main subjective scoring systems used in assessing lameness of livestock: numerical rating scale (NRS) and visual analog scale (VAS). For the purposes of our study we used a numerical rating 4 point scale (NRS) developed by Zinpro. The embedded microcomputer-based CASFP was developed at Iowa State University to objectively identify varying severities of lameness among sows. This force plate measures mean weight (kg) of each individual foot and was developed to be sensitive enough to recognize lameness undetectable by subjective scoring. The results of this study confirm that the Zinpro NRS locomotion scoring system is repeatable, and user friendly approach for diagnosing lameness in sows with 71.4% observer agreeability. A library of approximately 150 hours of sow gait video footage in HD format was created, which demonstrates a wide range of clinical severities and can be used to train producers and veterinarians to recognize various severities of lameness. There was no significant difference between mean weights (kg) placed on each foot among treatment (control, sodium salicylate, Banamine) groups recorded on the last day of treatment (Day +6). CASFP for all four feet was analyzed statistically for each individual foot (left front (LF), right front (RF), left rear (LR), right rear (RR)) and was compared to the other non-injected feet on Day -1 (sound day) and Day +1 (lame day). When the LF and RF feet were injected, there was a significant decrease in the weight being placed on the injected foot on Day +1 (P<0.05). The majority of sows returned to soundness by Day+6 however some sows did continue to exhibit lameness past Day +6. In conclusion, based on the main objectives addressed in this paper we have: (1) validated a robust observational lameness scoring system and created a vast library of visual material for education (2) confirmed that sodium salicylate and flunixin meglumine at the dose and length given did not provide significant pain relief for lameness using this model of lameness (3) and validated the CASFP as an objective assessment tool for sow lameness. Questions about the trial, conclusions, or access to the video library can be addressed to Dr. Locke Karriker using email: email@example.com or by phone: 515-294-2283.