Platelets are small, anucleated cell fragments derived from megakaryocytes in the bone marrow, playing a key role in hemostasis and thrombosis in horses. They contribute to the formation of blood clots by adhering to the site of vascular injury, aggregating with one another, and facilitating the coagulation process. In equine medicine, platelet count and function are important parameters in assessing bleeding disorders and thrombotic conditions. Variations in platelet count can indicate underlying health issues, such as inflammation, infection, or bone marrow disorders. This page compiles peer-reviewed research studies and scholarly articles that explore the physiology, pathology, and clinical implications of platelets in equine health.
Jain NC.Comparative morphology of platelets of the dog, cat, cow, horse, sheep, and goat was studied with the scanning electron microscope and was found generally similar. Most of the platelets were slightly biconvex of flat with relatively smooth surface and even contour. Some of these platelets had few short marginal filaments, oriny protuberances on the surface. A small number of platelets exhibited surface irregularity and few long pseudopods which were thought to result from platelet activation during the processing of blood. The number os such irregular platelets increased in stored blood and in...
Carter EI, Valli VE, McSherry BJ, Milne FJ, Robinson GA, Lumsden JH.Three Standardbred horses were given 0.2 mg (1 mCi) of (75)selenomethionine intravenously and a second group of three were given 10 mCi of tritiated diisopropylfluorophosphate (0.5 mg) intravenously. Observations on labeled cells were continued for 250 days after radioselenium injection and 160 days after tritium injection. The lifespan of erythrocytes using (75)selenmethionine was 155 +/- 10 days and 148 +/- 7.8 days using tritiated diisopropylfluorophosphate. There was no significant difference at the 10% level between the lifespans, using these labels. The uptake of radioselenium into eryth...
Carter EI, Valli VE, McSherry BJ.The peripheral blood cells from Standard bred horses were subjected to procedures which will separate equine peripheral blood cells with good precision and efficiency into red cell, leukocyte, and platelet fractions. The separated cells have normal morphology and the differential count of the separated granulocytes and lymphocytes is unchanged from that of the original sample.
Abramson HA.1. The cataphoretic velocity of blood platelets (horse) in plasma has been found to be between 40 and 51 micro per sec. per volt per cm. The mean velocity obtained from five horses is . 45 micro per sec. per volt per cm. 2. The cataphoretic velocity of polymorphonuclear leucocytes in similar specimens is practically identical with that of the platelets. This is noteworthy because of the fact that lymphocytes and red cells have different speeds. 3. With spontaneous agglutination of platelets, white cells and red cells, there is no change in the cataphoretic velocity incidental to aggregation. 4...
Mazzuchini MP, Lisboa FP, de Castro JI, Alvarenga MA, Segabinazzi LGTM, Canisso IF.Endometritis is the leading cause of subfertility in horses, and it is a clinical problem where historically antibiotics have not always been used with prudent justification. Because of this, alternative therapies to treat endometritis are necessary for the rational use of antibiotics. Objective: To assess the in vitro antimicrobial activity of non-traditional therapies commonly used in clinical practice against microorganisms causing infectious endometritis in mares. Methods: In vitro experiments. Methods: A microdilution technique was performed to determine the minimum inhibitory concentrati...
Aragona F, Giannetto C, Piccione G, Licata P, Deniz Ö, Fazio F.The aim of the present study was the evaluation of the bioaccumulation of cadmium (Cd), Zinc (Zn), Chrome (Cr), Lead (Pb), Iron (Fe) and Copper (Cu), in the blood, serum, tail and mane of horses from the industrialized area of Milazzo (Messina, Sicily), to understand the relationships between haematological parameters: Red Blood Cells (RBCs), White Blood Cells (WBCs), Haemoglobin (Hb), Haematocrit (Hct), Mean Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin (MCH), Mean Corpuscular Haemoglobin Concentration (MCHC), Platelets (PLTs) and the concentrations of trace elements. Blood and hair ...
Guidoni K, Chiaradia E, Pepe M, Di Meo A, Tognoloni A, Seccaroni M, Beccati F.Intra-articular corticosteroids, such as triamcinolone acetonide (TA), help reduce pain related to osteoarthritis (OA), but they may impair cartilage metabolism. In contrast, platelet-rich plasma (PRP) therapy, a regenerative therapy, has shown potential to promote healing and regeneration of articular cartilage. This study investigates the effects of combining PRP with TA to treat osteoarthritis in racehorses. The study proposes that PRP injection following TA treatment could reduce side effects and improve treatment outcomes. Firstly, in the in vitro study, chondrocytes were exposed to diffe...
Boger BL, Kinsley MA, Yob CJ, Knott LE, Manfredi JM.To determine if equine platelet-rich plasma (PRP) contains Dickkopf-1 (Dkk-1) and, if so, to quantify the amount of Dkk-1 in bovine thrombin (BT)-activated PRP and a control platelet lysate created using a freeze-thaw (FT) method. Unassigned: 10 adult horses were used in this experimental study. Blood was collected and processed in November 2019 and stored at -80 °C until the ELISAs were performed in October of 2023. Blood was collected from each horse, and PRP was created using a commercially available kit. Known concentrations of platelets were activated using BT or by an FT cycle to create...
Barot D, Usimaki A, Linardi RL, Arensberg CM, Ortved KF.Quantify the concentration of α2-macroglobulin (A2M), immunomodulatory cytokines, and TGF-β1 factors in 4 commercially available autologous blood-based products including conditioned A2M (CA2M; Alpha2EQ; Astaria Global), autologous protein solution (APS; Pro-Stride; Zoetis), platelet-rich plasma (PRP; Restigen; Zoetis), and autologous conditioned plasma (ACP; Arthrex ACP). We hypothesized that CA2M would have higher concentrations of A2M and lower concentrations of cytokines and growth factors compared to APS, PRP, and ACP. Unassigned: Blood was obtained from 6 healthy, adult horses and proc...
Long S, Maleas G, Belacic ZA, Quam VG, Durgam S.To analyze the cellular, growth factor, and cytokine composition of equine sternal bone marrow aspirate (BMA) and laboratory-centrifuged BMA concentrate (BMAC). Unassigned: This was an in vitro experimental study. Cellular composition, growth factors (IGF-I, VEGF, PDGF, TGF-β1), and cytokines (IL-6, IL-10, tumor necrosis factor-α (TNF-α), and IL-1 receptor antagonist protein [IL-1Ra]) were quantified using a standard automated hematology analyzer and ELISA methods, respectively, in donor-matched BMA, BMAC (in-house centrifugation protocol), whole blood, and platelet-rich plasma (E-PET; Pall...
Al-Khaldi KO, Al-Ruzaiqi KH, Babji AS, Lim SJ, Sadiq MB, Yimer N.Exercise-induced oxidative stress and inflammation adversely affect the health and performance of athletic horses. This study aimed to evaluate the safety of edible bird's nest (EBN) supplementation and its potential anti-inflammatory and immunomodulatory effects in Arabian race stallions during exercise. Key objectives included assessing EBN's impact on hepatic and renal function, hematological profiles, and sialic acid (SA) levels. Unassigned: Two experiments were conducted on 18 Arabian stallions. In Experiment 1, six healthy stallions were divided into control (n = 2) and EBN-supplemented ...
Carmona JU, López C.(1) Background: Tendon and ligament injuries are a leading cause of lameness in horses, with significant economic implications. Platelet-rich plasma (PRP) has gained attention for its regenerative potential, but its efficacy remains uncertain due to inconsistent study designs and reporting. (2) Methods: This systematic review, following the PRISMA guidelines, evaluated 22 studies (clinical and experimental) to assess the safety and efficacy of PRP in treating equine tendon and ligament injuries. The risk of bias was analyzed using the ROBINS-I and RoB 2.0 tools. (3) Results: PRP demonstrated a...
Clarke EJ, Jensen A, Gillen AM, Bardell D, Senior M, Anderson JR, Peffers MJ.To determine the protein composition of equine platelet-rich plasma (PRP) and PRP-derived extracellular vesicles (EVs) and evaluate their effects on tendon inflammation in vitro. As tendon injuries are common in horses and treatment with PRP derived from the horse's own blood shows promise, but outcomes vary due to inconsistent composition. PRP contains EVs that facilitate cell communication. Unassigned: From December 2022 through May 2023, equine plasma (n = 3, adult) was isolated via double centrifugation and PRP produced using a commercial kit. Extracellular vesicles were isolated using dif...
Collins E, Barr E, Zhang C, Steadman M, Gilger B, Henriksen ML.To describe the most efficient topical horizontally centrifuged platelet-rich fibrin (H-PRF) treatment protocol for equine ulcerative keratitis (EUK) that is easy to use, and to report the preliminary concentration of growth factors and cytokines in equine H-PRF. Unassigned: 5 client-owned horses diagnosed with EUK were enrolled over an 11-month period. Unassigned: 3 horses were geldings, and 2 were mares. The mean (± SD) age was 5.95 ± 5.01 years. The owners' main goal was to avoid surgery for EUK. Unassigned: H-PRF was used in 3 different protocols: solid H-PRF, sutured to the EUK area (n ...
Munoz Moran JA.This study was performed to evaluate the efficacy of intra-articular (IA) injections of a combination of platelet rich plasma (PRP) and hyaluronic acid (HA) on joint effusion following arthroscopic removal of OCD in the tarso-crural joint (TCJ) in young Andalusian horses. Methods: Forty Andalusian horses diagnosed with OCD of the distal intermediate ridge of the tibia (DIRT) were included in the study. Horses enrolled in this study had persisting synovial effusion after arthroscopic removal of OCD in the TCJ. A subjective semi-quantitative effusion score was adopted in the study to define the ...
Kooy S, Constant J, Cole R, Boone L.Clinical use of blood-derived intra-articular therapies, such as platelet-rich plasma (PRP), have increased in equine athletes due to their proposed disease-modifying effects. Need for a shelf-stable, allogeneic PRP product with known composition for standardized treatment exists. The objective of this study was to compare systemic and local effects of a single intra-articular injection of equine leucoreduced allogeneic pooled freeze-dried PRP (alloPRP) to a placebo control (saline) in normal, healthy equine joints. Unassigned: Twelve healthy horses were randomly assigned to either control (sa...
Friend MM, McGaffigan EM, Hall SM, Staniar WB, Smarsh DN.Equine blood samples are often collected in uncontrolled, distant environments and stored for later analysis. Objective: This study aimed to determine how sample storage methods influence complete blood count (CBC) parameters, hypothesizing that temperature and time elapsed from collection to analysis would affect CBC parameters. Methods: Blood samples were collected from 10 healthy Quarter Horse mares (age: 13 ± 4.5 years old) and stored in EDTA tubes at room temperature (22°C), above ice (8°C), refrigerated (4°C), or in contact with ice (2°C). The IDEXX ProcyteDx was used to obtain CBCs...
McKenna KD, Struble SE, Max LNF, Linardi RL, Ortved KF.To quantify platelets, leukocytes, cytokines, and growth factors in ProVet autologous platelet concentrate (APC). We hypothesized that APC would contain significantly increased leukocytes and platelets compared to whole blood and significantly increased concentrations of anti-inflammatory cytokines and growth factors compared to serum. Unassigned: Blood was obtained from 6 horses and processed to produce APC. Leukocyte and platelet concentrations were quantified in whole blood and APC. Cytokines, including interleukin (IL)-1β, IL-4, IL-6, IL-10, tumor necrosis factor-α, and IL-1Ra, and growt...
