Bone marrow in horses is a spongy tissue found within the cavities of certain bones, such as the pelvis, ribs, and femur. It is a vital component of the hematopoietic system, responsible for the production of blood cells, including red blood cells, white blood cells, and platelets. These cells are crucial for oxygen transport, immune function, and blood clotting, respectively. Bone marrow consists of two types: red marrow, which is actively involved in blood cell production, and yellow marrow, which primarily stores fat. The composition and activity of bone marrow can change with age, health status, and physiological demands. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and clinical implications of bone marrow in equine health and disease.
Cheville NF, Prasse K, van der Maaten M, Boothe AD.A newborn foal developed generalized cutaneous mastocytosis characterized by multiple elevated nodules of mast cells in skin and basophil hyperplasia in bone marrow. Skin lesions began as small aggregates of mast cells that progressively enlarged, ulcerated, and regressed spontaneously. Eosinophil infiltration, collagen necrosis, and fibroplasia were characteristic of advanced lesions. Many new lesions developed during the first month of life but numbers progressively diminished. Large numbers of mast cells were present in biopsies of lymph node, spleen and bone marrow. Discrete aggregates of ...
Everett JB, Menarim BC, Barrett SH, Bogers SH, Byron CR, Pleasant RS, Werre SR, Dahlgren LA.Osteoarthritis (OA) can be debilitating and is related to impaired resolution of synovial inflammation. Current treatments offer temporary relief of clinical signs, but have potentially deleterious side effects. Bone marrow mononuclear cells (BMNC) are a rich source of macrophage progenitors that have the ability to reduce OA symptoms in people and inflammation in experimentally-induced synovitis in horses. The objective of this study was to evaluate the ability of intra-articular BMNC therapy to improve clinical signs of naturally occurring equine OA. Horses presenting with clinical and radio...
Paraschou G, Xue C, Egan R, Bolfa P.Lymphoma is a common neoplasm in horses but is reported much less commonly in donkeys. In this case report, we describe the macroscopic, microscopic and immunohistochemical features of a multicentric lymphoma with intestinal and bone marrow involvement. Methods: A geriatric female donkey with history of chronic lameness was found dead. Post-mortem examination revealed advanced emaciation, periodontal disease, left front foot laminitis and multiple, soft, white to yellow tan intestinal transmural masses, up to 12 cm in diameter. Cytology suggested a round cell intestinal neoplasm. The femur of...
Gaesser AM, Usimaki AIJ, Barot DA, Linardi RL, Molugu S, Musante L, Ortved KF.Mesenchymal stem cell (MSC) extracellular vesicles (EVs) have emerged as a biotherapeutic for osteoarthritis; however, manufacturing large quantities is not practical using traditional monolayer (2-D) culture. We aimed to examine the effects of 3-D and 2-D culture 2 types of media: Dulbecco modified Eagle medium and a commercially available medium (CM) on EV yield. Methods: Banked bone marrow-derived MSCs (BM-MSCs) from 6 healthy, young horses were used. Methods: 4 microcarriers (collagen-coated polystyrene, uncoated polystyrene, collagen-coated dextran, and uncoated dextran) were tested in st...
Quam VG, Belacic ZA, Long S, Rice HC, Dhar MS, Durgam S.Safe, efficacious therapy for treating degenerate deep digital flexor tendon (DDFT) and navicular bone fibrocartilage (NBF) in navicular horses is critically necessary. While archetypal orthobiologic therapies for navicular disease are used empirically, their safety and efficacy are unknown. Mesenchymal stem cell-derived extracellular vesicles (EV) may overcome several limitations of current orthobiologic therapies. Objective: To (1) characterise cytokine and growth factor profiles of equine bone marrow mesenchymal stem cell (BM-MSC)-derived extracellular vesicles (BM-EV) and (2) evaluate the ...
Hewitt-Dedman CL, Kershaw LE, Schwarz T, Del-Pozo J, Duncan J, Daniel CR, Cillán-García E, Pressanto MC, Taylor SE.Magnetic resonance spectroscopy (MRS) has been used to investigate metabolic changes within human bone. It may be possible to use MRS to investigate bone metabolism and fracture risk in the distal third metacarpal/tarsal bone (MC/MTIII) in racehorses. Objective: To determine the feasibility of using MRS as a quantitative imaging technique in equine bone by using the H spectra for the MC/MTIII to calculate fat content (FC). Methods: Observational cross-sectional study. Methods: Limbs from Thoroughbred racehorses were collected from horses that died or were subjected to euthanasia on racecourses...
Son JK, De Paz P, Kim J, Sanaei R, Ryu S, Bailey S, Davies HMS.Changes in the third metacarpal (MC3) mid-diaphyseal dimensions were measured radiographically in young Thoroughbred racehorses through race training and found to be associated with a higher risk of shin soreness. However, it is still unclear whether such negative MC3 morphologies are set congenitally or through development. Objective: To quantify MC3 bone dimensional changes through growth. Methods: Longitudinal. Methods: Twenty privately owned Thoroughbred foals were radiographed bimonthly from birth to 14 months of age. Four linear MC3 parameters (proximodistal MC3 length, mid-diaphyseal do...
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...
Nagy A, Dyson SJ.There is no description of comparative magnetic resonance imaging (MRI) and fan-beam computed tomography (CT) findings in the fetlock of lame sports horses. Objective: To document low-field MRI and fan-beam CT diagnoses in the lame and nonlame limbs of sports horses with fetlock region pain, and to evaluate whether combined imaging provides superior information to either technique alone. Methods: Retrospective descriptive study. Methods: Clinical records of sports horses with pain causing lameness localised to the metacarpo/metatarsophalangeal joint region that had undergone fan-beam CT and lo...
Euppayo T, Siengdee P, Limlenglert P, Nganvongpanit K, Watanabe G, Kasashima Y, Arai K.The self-renewal capacity of chondrocytes in osteoarthritis (OA) joints is limited, and mesenchymal stem cells (MSCs) are crucial in disease treatment. This study established an OA model from equine bone marrow-derived mesenchymal stem cells (eBMSCs). The eBMSCs were cultured and differentiated into chondrocytes to generate cartilage pellets, which were induced for 7 d with inflammatory cytokines, interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) to mimic OA conditions. Treated culture medium was collected to estimate enzyme activity (MMP-2, MMP-3, and MMP-9) using zymograph...
Lee S, Kyaw MT, Harada K, Kusakabe KT, Igase M, Sasaki N.Generally, most mesenchymal stem cells (MSCs) have lower pluripotency and limited differentiation potential than embryonic stem cells (ESCs). However, a small subpopulation of MSCs, called multilineage differentiating stress-enduring (MUSE) cells, exhibit pluripotency. MUSE cells express stage-specific embryonic antigen 3 (SSEA-3), a sphingoglycolipid. Here, we isolated and investigated the pluripotency of SSEA-3-positive MSCs (MUSE cells). Six thoroughbred horses were used as test subjects. MSCs were harvested from the bone marrow of the thoracic vertebrae under ultrasound guidance. Harvested...
Contentin R, Jehl C, Commenchail K, Legendre F, Galéra P, Cassé F, Demoor M.Osteoarthritis (OA) affects millions of people globally, causing irreversible cartilage damage, chronic inflammation, and progressive joint dysfunction. Similarly, horses can develop OA spontaneously or due to their athletic careers, influenced by mechanical and biochemical factors. Current treatments primarily focus on symptom relief without promoting cartilage regeneration. In line with the 3Rs principles (refine, reduce, replace), the development of OA models is essential for advancing new therapeutic approaches against OA. In response to this need, the present study aimed to develop an m...
Chaipokam J, Rojnuckarin P.In Thailand, stem cell transplantation and horse antithymocyte globulin (ATG) are not accessible for most adult aplastic anemia (AA) patients. Alternative therapies are required. We conducted a cohort study of 110 adult AA patients treated with oxymetholone alone for at least 30 days from 2013 to 2023. Response at month 6 and prognostic factors were evaluated. The mean age was 63.4 years old and 58.2% were female. Severe and very severe AA (SAA/VSAA) comprised 64.5% and 3.6%, respectively. The initial oxymetholone daily dose was 150 mg in 66.4%. The overall response was 56.4% (50.7% for SAA/V...
Maguire M, Brusie R.To determine the outcome of skeletally mature performance horses with subchondral bone cysts and fissures in the proximal aspect of the first phalanx treated by lag screw compression. Unassigned: Case records of horses that underwent lag screw compression to treat subchondral bone lesions in the proximal aspect of the first phalanx were reviewed. Performance horses > 5 years old with lameness referrable to the fetlock region; radiographic or other advanced imaging evidence of subchondral bone lesions, with no other concurrent cause for lameness; and at least 6 months of follow-up data were inc...
Germonpré J, Lorenz I, Vandekerckhove LMJ, Duchateau L, Diekhoff T, Vanderperren K.Dual-energy computed tomography (DECT) is a promising advancement for detecting bone edema-like lesions (BME). However, its application in horses remains limited. The aim of this study was to evaluate DECT virtual-non-calcium (VNCa) imaging in the equine foot and establish which confounding factors could influence its applicability in clinical practice. The DECT VNCa map of 14 standing and 5 cadaveric (recumbent) cases with foot-related lameness was scored in consensus by two readers in comparison to MRI. Overall, 17/19 cases demonstrated BME on MRI, whereas 2 did not. Agreement between DECT V...
