title: Validation of a lameness model in sows using physiological and mechanical measurements.
abstract: The objective of this study was to develop a validated, transient, chemically induced lameness model in sows using subjective and objective lameness detection tools. Experiment 1 determined an effective joint injection technique based on volume and placement of dye using feet collected from 9 finisher pigs and 10 multiparity cull sow carcasses. Experiment 2 confirmed the injection technique in live animals and produced a transient clinical lameness in 4 anesthetized sows injected with amphotericin B (15 mg/mL) in the distal interphalangeal joints of the claw. Clinical lameness was assessed by a categorical lameness scoring system, and a postmortem visual confirmation of joint injection technique was obtained. In Exp. 3, 6 sows were injected with 0, 10, or 15 mg/mL amphotericin B in either the left or right hind foot and were monitored until clinical resolution. Treated sows demonstrated elevated clinical lameness scores. These changes resolved by 7 d after lameness induction. Control sows injected with sterile saline developed a clinical lameness score of 0.5, which resolved 72 h post injection. In Exp. 4, 36 sows were injected with 10 mg/mL amphotericin B in 1 of 4 injection sites (left front claws, right front claws, left rear claws, and right rear claws). All injected sows exhibited a decrease in maximum pressure, stance time, and number of sensors activated on the GaitFour (P < 0.05) sensor system. A static force plate also demonstrated a decrease in weight (kg) being placed on the injected foot when all feet were injected (P ≤ 0.05). Injection of amphotericin B induced a predictable acute lameness that resolved spontaneously and is an effective method to model lameness in sows.
authors.affiliation: Swine Medicine Education Center, College of Veterinary Medicine, Department of Animal Science, Cyclone Analyte Detection Service, Iowa State University, Ames, IA 50011, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Karriker
authors.forename: C E
authors.initials: CE
authors.lastname: Abell
authors.forename: M D
authors.initials: MD
authors.lastname: Pairis-Garcia
authors.forename: W A
authors.initials: WA
authors.lastname: Holt
authors.forename: G
authors.initials: G
authors.lastname: Sun
authors.forename: J F
authors.initials: JF
authors.lastname: Coetzee
authors.forename: A K
authors.initials: AK
authors.lastname: Johnson
authors.forename: S J
authors.initials: SJ
authors.lastname: Hoff
authors.forename: K J
authors.initials: KJ
authors.lastname: Stalder
mesh_terms: D000666:Amphotericin B / Q000633:toxicity; D000818:Animals; D000935:Antifungal Agents / Q000633:toxicity; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D007592:Joint Diseases / Q000139:chemically induced / Q000473:pathology / Q000662:veterinary; D007794:Lameness, Animal / Q000139:chemically induced* / Q000473:pathology; D013552:Swine; D013553:Swine Diseases / Q000139:chemically induced* / Q000473:pathology
chemical_list: D000935:Antifungal Agents; D000666:Amphotericin B