Neuenschwander HM, et al. J Vet Sci. 2019 Oct;20:e67. https://doi.org/10.4142/jvs.2019.20.e67

Blood-derived autologous products are frequently used in both human and equine medicine to treat musculoskeletal disorders. These products, especially the platelet-rich plasma (PRP), may contain high concentrations of growth factors (GFs), and thus improve healing in several tissues. Nevertheless, the procedures for preparation of PRP are currently non-standardized. Several protocols, which are based on distinct centrifugation patterns (rotation speed and time), result in PRPs with different characteristics, concerning platelet and GFs concentrations, as well as platelet activation. The aim of the present study was to compare two different protocols for PRP preparation: protocol (A) that is based on a single-centrifugation step; protocol (B), which included two sequential centrifugation steps (double-centrifugation). The results here reported show that the double-centrifugation protocol resulted in higher platelet concentration, while leukocytes were not concentrated by this procedure. Although platelet activation and aggregation were increased in this protocol in comparison to the single-centrifugation one, the TGF-β1 concentration was also higher. Pearson’s correlation coefficients gave a significant, positive correlation between the platelet counts and TGF-β1 concentration. In conclusion, although the double-centrifugation protocol caused premature platelet aggregation, it seems to be an effective method for preparation of PRP with high platelet and TGF-β1 concentrations.

Like most mammalian, polyphasic sleep, equine sleep can be divided into two phases: the REM (rapid eye movement) phase and the NREM (non-rapid eye movement) phase. For this study, a randomized crossover experiment was conducted using ten purebred Lusitano horses, all dressage athletes aged from three to seven years old. The horses were filmed before the intervention to characterize their sleep patterns. REM sleep deprivation was achieved by not letting the horses attain sternal or lateral recumbency for three consecutive days, totaling 72 h. A spatial memory task and a visual attention test were performed. A recording time of 48 h appeared to be long enough to characterize the sleep patterns of the stalled horses. The total recumbency time of the studied population was lower than that previously reported in horses. Although the recumbency times before and after the intervention were similar, there was a tendency shown by the delta (p = 0.0839) towards an increased time needed to resolve spatial memory tasks in the sleep-deprived group. Future studies may deepen the understanding of horse sleep requirements and patterns, and the effects of environmental changes on horse sleep.

Ozone (O3) therapy has been used for medical procedures for centuries; however, there are no extensive studies on its utilization in horses. This study aimed to evaluate the application of transrectal O3 on horses by physical and laboratorial evaluation, and production of reactive oxygen species (ROS). Sixteen healthy horses were separated in two groups: a control group (CG) and a group treated with O3 (TG). The TG animals received 1L of an oxygen and O3 mixture transrectally. The initial dose was 10µg/ml for the first two applications, 15μg/ml for the following two applications, and 20μg/ml for the next six applications. The CG animals received 1L of oxygen transrectally. In TG animals no variations in the physical examination were detected; furthermore, TG animals did not exhibit changes in biochemical evaluation results, fibrinogen concentrations, or ROS production. TG animals had increased red blood cell counts, hemoglobin concentrations, and packet cell volume values in comparison to the baseline and CG values. We could infer that O3 affected the red blood cell counts and improved rhetological properties of the blood. The transrectal application of O3 in horses is safe and can indirectly improve the oxygenation and metabolism of tissues.

Several studies in human and equine medicine have produced controversial results regarding the role of dimethylsulfoxide (DMSO) as a therapeutic agent. This study aimed to evaluate the effect of joint lavage with different DMSO concentrations on biomarkers of synovial fluid inflammation and cartilage degradation in joints with lipopolysaccharide (LPS)-induced synovitis. Twenty-six tibiotarsal joints of 13 horses were randomly distributed into four groups (lactated Ringer’s solution; 5% DMSO in lactated Ringer’s; 10% DMSO in lactated Ringer’s; and sham). All animals were evaluated for the presence of lameness, and synovial fluid analyses were performed at 0 h, 1 h, 8 h, 24 h, and 48 h (T0, T1, T8, T24, and T48, respectively). The white blood cell counts (WBC), total protein (TP), urea, prostaglandin E2 (PGE2), interleukin (IL)-1β, IL-6, IL-10, tumor necrosis factor-α (TNF-α), hyaluronic acid (HA), and chondroitin sulfate (CS) concentrations were measured. The WBC counts and PGE2, IL-1β, IL-6, and TP concentrations increased in all groups at T8 compared to baseline values (p < 0.05). At T48, only the 5% DMSO and 10% DMSO groups showed a significant decrease in WBC counts (p < 0.05). Furthermore, the 10% DMSO group had lower concentrations of PGE2 and IL-1β at T48 than at T8 (p < 0.05) and presented lower IL-6 levels than the5% DMSO and lactated Ringer’s groups at T24. All groups showed an increase in CS concentration after LPS-induced synovitis. Joint lavage with 10% DMSO in lactated Ringer’s has anti-inflammatory but not chondroprotective effects.

Introduction: Platelet-rich plasma (PRP) is commonly used by equine veterinarians. Although PRP is considered a feasible and affordable orthobiologic, its use has been associated with certain drawbacks, such as the time required for protocols and the necessity of using a fresh product, which is usually prepared at the time of use. In this context, the present study aimed to produce PRP-derived orthobiologics with the potential to be stored for longer periods while maintaining similar growth factor contents. Methods: PRP was prepared from six donors and subjected to additional processing: lysis, yielding Platelet Lysate (PL), and freeze-drying, yielding lyophilized PRP (FD-PRP). The three products were stored for 30 days at different temperatures (−80°C, −20°C, and room temperature [RT]). Additionally, orthobiologics from a single donor were also subjected to longer periods of storage: PRP, FD-PRP, and PL for 1 and 2 years at −80°C and −20°C; and FD-PRP at RT was stored for 1 year with cryoprotectant and 30 days without cryoprotectant. Results: Storage for 30 days presented distinct pattern related to the temperatures on each orthobiologic: there was no difference on TGF-β1 concentrations between the hemocomponents at −80°C, PL retained a high TGF-β1 concentration at −20°C, PRP and FD-PRP showed a slight increase in TGF-β1 content at RT when compared to PL. RT also resulted in decreases in IL-1β, IL-10, and TNF-α concentrations in all hemocomponents. Discussion: The protocols used in this study efficiently produced hemocomponents with similar content, offering some benefits, such as the possibility of preparing major volumes at the same time, preparing aliquots that would be ready to be used throughout the entire treatment, and storing them in farms, clinics, and hospitals.