Pharmacological effects of tiludronate in horses after long-term immobilization.

INTRODUCTION: Tiludronate, a bisphosphonate, has recently been introduced in veterinary medicine to treat orthopedic conditions in the horse. This study was designed to evaluate its effects on biochemical biomarkers of bone metabolism and on bone density and structure in an experimental model of disuse osteoporosis induced by cast application in horses. METHODS: Two groups of eight horses were immobilized during 8 weeks. The first group (P-group) received a placebo, and the second group (T-group) received tiludronate 1 mg/kg by slow IV infusion. Both treatments were administered twice, 28 days apart. Immobilization consisted of stall rest with the left forelimb packed in a fiberglass cast. It was followed by a 4-week remobilization period and an 8-week standardized training protocol. One biomarker of bone resorption, the C-telopeptides of type I collagen cross-links (CTX-1) and one biomarker of bone formation, the bone isoenzyme of alkaline phosphatase (bone ALP), were assessed. Metacarpus III (MCIII) bone mineral density (BMD) and speed of sound (SOS) were evaluated respectively by dual energy X-ray absorptiometry (DEXA) and quantitative ultrasonography (QUS). Lameness was regularly assessed during the remobilization and training periods. Group- and time-related effects were tested by analysis of variance on repeated measurements. RESULTS: A rapid, transient and significant decrease in CTX-1 concentration was seen after each treatment in the T-group only. No significant differences between groups were seen in the evolution of bone ALP activity. At the end of the experiment, the loss of MCIII BMD measured by DEXA in the immobilized limb was significantly less in the T-group than in the P-group. The MCIII SOS measured by QUS did not significantly vary within or between groups throughout the study. DISCUSSION AND CONCLUSIONS: Tiludronate was found to significantly reduce bone resorption during immobilization, as well as to prevent long-term osteopenia in the immobilized limb. Disuse osteopenia did not affect the lateral superficial cortex of MCIII.

Transarterial coil embolisation in 31 horses (1999-2002) with guttural pouch mycosis: a 2-year follow-up.

REASONS FOR PERFORMING STUDY: There have been no previously published large case series describing short- and long-term outcome of transarterial coil embolisation (TCE) in horses with guttural pouch mycosis (GPM). OBJECTIVES: To describe the clinical and surgical features of horses with GPM presented at the Veterinary School of Lyon during a 28 month period; and to evaluate immediate to long-term results of TCE as a treatment. METHODS: Medical records of all horses with GPM treated with TCE between February 1999 and July 2002 were analysed. To be included in the study, no other surgical or medical treatment for the mycosis was administered. Subject details, case history and results of initial clinical examination and endoscopy were reviewed. For all individuals, evaluation of long-term complications and case evolution was based on owner or trainer interviews between 24 and 41 months after surgery. RESULTS: Thirty-one horses were identified with unilateral (n = 25) or bilateral (n = 6) GPM affecting only the medial (n = 28), only the lateral (n = 2) or both compartments simultaneously (n = 7). Of the 23 individuals presented with epistaxis, 20 showed complete resolution of the problem. Of the 19 horses presented with neurological signs, 2 were subjected to euthanasia for persistence of severe dysphagia. Prognosis for survival was excellent (84%) and prognosis for return at the level expected by the owner or trainer was good (71%). CONCLUSIONS AND POTENTIAL RELEVANCE: TCE of horses affected with GPM is an effective method of preventing haemorrhage and resolving the majority of mycotic lesions without further specific treatment. Treated horses did not present relapse of mycosis during the follow-up period.