The objective of this study was to investigate the effect of routine dental occlusal equilibration treatment on dressage horse performance. Sixteen horses (11 treated; 5 untreated) ridden by a single rider performed a standardized dressage test twice and were scored by two experienced dressage judges according to recognized movements and rider cues. All horses were sedated and a full-mouth speculum was used to facilitate a complete oral examination. Treated horses had dental equilibration performed using a motorized dental instrument. The horses performed a second test 48-hours after dental equilibration, exactly as the baseline test, with the judges and rider blinded as to treatment group. The total test score as well as the individual movement scores were evaluated for equality of variance and statistical tests were applied to determine the influence of treatment. There was no significant improvement in the test score of horses that had received occlusal equilibration.
Background Although the temporomandibular joint (TMJ) is the major contact point between the reins in the riders’ hand, the bit in the mouth, and the rest of the horse under saddle, the role of inflammation of this joint on equine locomotion and rein tension is unknown. Objective To determine the effect of acute TMJ inflammation on rein-tension and horse movement when horses were long-reined on a treadmill. Study design A randomized, controlled, cross-over design. Methods Five horses were trained by one clinician to walk and trot on a treadmill wearing long-reining equipment instrumented with a rein-tension device and reflective optical tracking markers. Subjective assessment of horse’s dominant side, and movement, were determined without rein-tension (free walk and trot); and with rein-tension (long-reined walk and trot). Continuous rein-force data from both sides were collected over ~60s from each trial. Movement was recorded using a 12-camera optical motion capture system. One randomly assigned TMJ was subsequently injected with lipopolysaccharide and the treadmill tests repeated by investigators blinded to treatment side. A second, identical assessment was performed 10 days later with the opposite TMJ being the target of intervention. Results All horses showed reduced rein-tension on the injected (inflamed) side. Increased rein-tension was required on the non-injected side at trot, to maintain them in the correct position on the treadmill post-injection. The only kinematic variable to show any significant change due to rein tension or TMJ inflammation during the walk or trot was an increase in forward head tilt in the presence of rein tension in the trot after injection. Main limitations Low number of horses and investigation of response to acute inflammation only. Conclusion TMJ inflammation changed, subjectively and objectively, the response to rein-input, but the horses did not become lame.
HistoryA 15-year-old Quarter Horse gelding was referred with a 5-day history of lameness.Clinical examination revealed that the horse had a grade 3 of 5 lameness of the right forelimb.Signs of pain were evident when pressure was applied with hoof testers to the medial aspect of the frog.There was palpable effusion of the dorsal pouch of the distal interphalangeal joint (coffin joint), and the distal aspect of the forelimb to the level of the metacarpophalangeal joint (fetlock joint) was also mildly swollen and edematous.Synovial fluid acquired by arthrocentesis of the distal interphalangeal joint was slightly cloudy and had a low viscosity.Cytologic examination of synovial fluid revealed a nucleated cell count of 4.4 X 10 9 cells/L (81.5% nondegenerative neutrophils and 18.5% small and large mononuclear cells) and a total protein concentration of 44 g/L.Intra-articular analgesic administration did not result in an improvement in lameness.Radiographic views of the right forefoot were obtained (Figure 1).Determine whether additional imaging studies are required, or make your diagnosis from Figure 1-then turn the page
A horse was initially diagnosed with hemarthrosis and desmitis of the long medial collateral ligament of the right tarsus and later developed prominent enthesiophytosis at the site of insertion of the ligament's deep portion. Hemarthrosis due to intra- or peri-articular pathology can cause recurrent lameness, even without evident external trauma.
This addition to the Equine Made Series provides detailed, easy to read guidelines for performance of common endoscopic procedures in the horse. It includes step-by-step guidelines endoscopy of the upper airway, gastrointestinal, urinary and reproductive systems. A detailed section covering arthroscopy, including the temperomandicular joint, is esp
The aim of the study was to determine whether a full-thickness equine coronary band graft can be successfully applied to acute wounds with excision of the coronary band and secondly, to describe the use of coronary band excision for the treatment of a clinical case of painful, abnormal hoof growth in a mature horse.Using 5 equids, a pilot study was performed in order to determine whether a 4 cm 2 graft involving the skin and coronary band, on the dorsal midline of both front feet, could be transferred within and between subjects.A defect in one horse was left open as a control but was managed identically in all other respects.Limbs were immobilized in a fiberglass cast, from the ground to mid-pastern, for four weeks and subsequently monitored at pasture for nine months.After euthanasia, skin samples from the neck and surgical sites were submitted for genotype analyses.A clinical case of lameness due to a recurrent hoof crack in the hind limb, was subsequently treated by coronary band excision in the same manner as the experimental control horse.During the study all defects healed without complication and resulted in hoof horn production.There were no full thickness horn cracks and the vertical junction between the excision site (skin and keratinised horn) and parent tissue was contiguous.DNA analyses suggested that none of the grafts were accepted, despite all sites healing.The clinical case resulted in normal hoof horn growth and cessation of lameness following surgery.Coronary grafting in the horse did not result in graft take.Results suggest that removing affected horn and coronary band with subsequent immobilization could be a treatment for recalcitrant coronary band defects and abnormal horn production in the horse.
Equine pituitary pars intermedia dysfunction (PPID) is characterized by hyperplasia of the pars intermedia (PI) melanotrophs of the pituitary gland (PG), and increased production of proopiomelanocortin (POMC). POMC is cleaved by prohormone convertase 1 (PC1) to produce adrenocorticotropic hormone (ACTH), and further processing of ACTH by PC2 to produce alpha-melanocyte stimulating hormone (α-MSH) and corticotropin-like intermediate peptide (CLIP). High plasma ACTH concentrations in horses with PPID might be related to reduced conversion of ACTH to α-MSH by PCs. The hypothesis of this study was that PC1 and PC2 expression in the pituitary gland are altered in PPID, resulting in an abnormal relative abundance of POMC derived proteins. The objectives of this study were to identify the partial sequences of equine POMC, PC1, and PC2 mRNAs; and to determine whether the expression of POMC, PC1, and PC2 mRNAs in whole pituitary extracts, and POMC-protein in the cavernous sinus blood of horses are altered in PPID. We confirmed (RT-PCR and sequencing) that the partial sequences obtained match the corresponding regions of predicted equine POMC, PC1 and PC2 sequences. The expression (quantification by RT-qPCR) of POMC, PC1 and PC2 mRNAs were found upregulated in the pituitary of horses with PPID. Plasma (measured using RIA/ELISA) ACTH and α-MSH were elevated in PPID horses. These results indicate distinct differences in gene and protein expression of POMC and its intermediates, and processing enzymes in PPID. It provides evidence to support the notion that local, pituitary-specific inadequacies in prohormone processing likely contribute to equine PPID.
