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cast forelimb. The cast forelimbs had a change in the appearance of the deep digital flexor tendon according to MRI immediately after removal of the cast. Numerous clinical, radiographic, CT, and MR abnormalities were visible at the end of the study period. The authors concluded that 8 weeks of cast


immobilisation induced changes in bone, cartilage, and periarticular soft tissues that were not reversed after 12 weeks of remobilisation. Cast application should be used judiciously in horses with musculoskeletal injuries, balancing appropriate stabilisation with potential morbidity secondary to cast placement.


New antifungal drugs for equine keratitis


This study by Darby Roberts and colleagues at North Carolina State University determined minimum inhibitory concentrations (MICs) of four fungal species isolated from horses with equine fungal keratitis to previously untested azole, echinocandin, and carboxamide antifungal drugs. In vitro assays were performed to determine the


susceptibility of Aspergillus flavus, A. fumigatus, Fusarium falciforme, and F. keratoplasticum to five antifungal drugs representing three modes of action. Luliconazole exhibited increased growth inhibition against


both Aspergillus and Fusarium compared to commonly used, standard antifungal drugs. MIC values for luliconazole at 0.001–0.002 µg/mL were at least 25-fold lower than all other antifungal drugs tested, including voriconazole. The increased antifungal activity of luliconazole observed


in this study warrants further investigation for its potential as an antifungal drug for equine fungal keratitis.


Liver fluke infection


In this study Aoife Quigley and colleagues in Ireland, Spain and the UK aimed to determine the susceptibility of horses to oral challenge infection with


metacercariae. The authors attempted an experimental infection of 10


horses with F. hepatica. Four were given 1000 metacercariae, four 500 metacercariae and two were sham-infected. Blood and faecal samples were taken at intervals up to 18 weeks post-infection. ELISA assays were used to assess sero- conversion in the experimental horses and also in a panel of sera from horses of known fluke status. No flukes were recovered from any of the livers, and no lesions that could be attributed to F. hepatica infection were observed. Coproantigen ELISA was negative throughout for all horses. Three antibody detection ELISAs, used to diagnose fasciolosis in other species, had limitations as diagnostic aids as determined using a panel of sera from horses of known F. hepatica infection status. Failure to establish infection after oral challenge raises


fundamental questions on the pathophysiology and epidemiology of equine fasciolosis.


Medial condylar fracture repair


This study by Sophie Boorman and colleagues in the USA reports the performance of Thoroughbred racehorses after


Fasciola hepatica


surgical repair of a medial condylar fracture of the third metacarpal/metatarsal bone. Forty-three horses surgically treated for medial condylar


fractures, 30 with previous racing experience, 13 without previous racing experience (nonexperienced) were studied. Medical records were reviewed for signalment, radiographic fracture characteristics, repair technique, and post-operative morbidity and mortality. Each experienced horse was matched with two horses randomly selected from its most recent race to serve as healthy controls. Racing performance parameters (race rating, competitive level, speed rating, performance index) and career racing statistics were compared with multiple regression models between injured experienced horses and controls. The career racing statistics for nonexperienced horses were evaluated. Reasons for nonreturn to racing were obtained. The median duration of follow-up was 6 years (minimum


2, maximum 10). Twenty-one of 43 (49%) horses raced again including 18/30 (60%) experienced horses and 3/13 (23%) nonexperienced horses. Higher preoperative racing performance parameters were associated with return to racing. Experienced horses were five times more likely to return to racing after medial condylar fracture repair, although their performance was generally lower than that of comparably uninjured horses.


S. WRIGHT EVE Editorial Office References


Ballou, M.E., Mueller, M.K. and Dowling-Guyer, S. (2020) Aging equines: understanding the experience of caring for a geriatric horse with a chronic condition. J. Equine Vet. Sci. https://doi.org/10.1016/j.jevs. 2020.102993. [Epub ahead of print].


Boorman, S., Richardson, D.W., Hogan, P.M., Stefanovski, D. and Levine, D.G. (2020) Racing performance after surgical repair of medial condylar fracture of the third metacarpal/metatarsal bone in thoroughbred racehorses. Vet. Surg. 49(4), 648–658


Hassel, D.M., Curley, T. and Hoaglund, E.L. (2020) Evaluation of fecal sand clearance in horses with naturally acquired colonic sand accumulation with a product containing probiotics, prebiotics, and psyllium. J. Equine Vet. Sci. https://doi.org/10.1016/j.jevs.2020. 102970. [Epub ahead of print].


Michanek, P., Toth, T., Bergstr€ om, E., Treffenberg-Pettersson, H. and


Bergh, A. (2020) Effect of infrared and red monochromatic light on equine wound healing. Equine Vet. J. https://doi.org/10.1111/evj. 13266. [Epub ahead of print].


Quigley, A., Sekiya, M., Garcia-Campos, A., Paz-Silva, A., Howell, A., Williams, D.J.L. and Mulcahy, G. (2020) Horses are susceptible to natural, but resistant to experimental, infection with the liver fluke, Fasciola hepatica. Vet. Parasitol. https://doi.org/10.1016/j.vetpar. 2020.109094. [Epub ahead of print].


Roberts, D., Cotter, H.V.T., Cubeta, M. and Gilger, B.C. (2020) In vitro susceptibility of Aspergillus and Fusarium associated with equine keratitis to new antifungal drugs. Vet. Ophthalmol. https://doi.org/ 10.1111/vop.12774. [Epub ahead of print].


Stewart, H.L., Werpy, N.M., McIlwraith, C.W. and Kawcak, C.E. (2020) Physiologic effects of long-term immobilization of the equine distal limb. Vet. Surg. https://doi.org/10.1111/vsu.13441. [Epub ahead of print].


Vera, L., Van Steenkiste, G., Decloedt, A., Chiers, K. and van Loon, G. (2020) Age-related differences in blood pressure, ultrasound-derived arterial diameters and arterial wall stiffness parameters in horses. Equine Vet. J. https://doi.org/10.1111/evj.13263. [Epub ahead of print].


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