Inflammation is a biological response of the horse's body to harmful stimuli, such as pathogens, damaged cells, or irritants. It is a complex process that involves the activation of immune cells, the release of inflammatory mediators, and changes in blood flow. In horses, inflammation can manifest in various forms, affecting different tissues and organs, including the joints, respiratory system, and skin. The inflammatory response is an essential component of the horse's immune system, aiming to eliminate the initial cause of cell injury, clear out damaged cells and tissues, and establish tissue repair. This topic page gathers peer-reviewed research studies and scholarly articles that explore the mechanisms, effects, and management of inflammation in equine health.
CRAWFORD M.This disease has a very long history, with the earliest written description by Vegetius in the fourth century A.D. It has many names, such as periodic ophthalmia, recurrent ophthalmia, iridocyclitis, uveitis, moon-blindness, etc. Periodic ophthalmia is perhaps the name more generally used, but I prefer to use recurrent iridocyclitis because (a) there is no definite fixed period between the recurrent attacks and (b) because the essential lesion is iridocyclitis.
Pain management in horses plays a pivotal role in the therapeutic approach to several diseases. Horses have cannabinoid receptors at the level of dorsal root ganglia, blood vessels, and synoviocytes that can be up or down- regulated by inflammatory conditions, justifying the possible efficacy of exogenous cannabinoids (i.e., phytocannabinoids) in managing several painful pathologies in this animal species. However, the current use of supplements containing cannabidiol (CBD) in equines is based on anecdotal evidence, without the support of sufficient pharmacokinetic studies. In humans, the conc...
Prudhomme J, Bardet C, Rakotoarivony I, Garros C, Bouhsira É, Lienard E.Insect bite hypersensitivity in horses ("sweet itch") is a common pruritic, chronic, seasonal, and recurrent dermatitis affecting approximately 10% of horses in France and is a major concern for the horse industry and private owners. This dermatitis results from an allergic reaction to the saliva of specific biting flies (Diptera: Nematocera), primarily from the Culicoides genus. Given the frequent occurrence of this health problem and the limited investigation in France, we conducted a field survey in the vicinity of a riding stable in southwestern France with a reported chronic case of recur...
Fikri F, Purnomo A, Maslamama ST, Purnama MTE.In the past 20 years, acupuncture has been utilized as an alternative therapy for equine laminitis despite a lack of clinical evidence to support its effectiveness. Information from previous studies needs to be evaluated holistically to verify the effectiveness of acupuncture. This meta-analysis aimed to comprehensively investigate the effectiveness of acupuncture as a treatment for laminitis in horses. Unassigned: A total of 7 studies out of 145 were selected in the PubMed, Scopus, Cochrane Library, and ProQuest databases using the keywords "equine laminitis," "acupuncture," "horses," and "la...
Bindi F, Nocera I, Meucci V, Vallesi G, Sala G, Spadari A, Rinnovati R, Bonelli F, Sgorbini M.This study investigated the plasma concentrations of symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA) in healthy horses and in horses affected by colic in relation to the type of colic and systemic inflammation response syndrome (SIRS) status. Upon admission (T0), horses underwent a physical examination, and the SIRS status was assessed. The horses with colic were divided retrospectively based on the type of colic, SIRS status, treatment, and outcome. SDMA and ADMA levels were measured at T0 and then every 24 h at four time points (T1, T2, T3, T4). Differences between ...
Płoneczka-Janeczko K, Armstrong E, Siemieniuch-Tartanus M, Magdziarz M.The aim of the study was to explore and characterise healthy foals' eye microbiomes in the first two months of life. Unassigned: Conjunctival swabs were collected three times, not later than 12 h after delivery and again at the end of the first and the second months of life from six clinically healthy foals of the Polish Konik breed. The average interval between the first and second samplings was 33.3 days and between the second and third was 35.6 days. Next-generation sequencing performed on a MiSeq sequencer in paired-end technology was used to analyse the composition of the conjunctival mic...
Żak-Bochenek A, Drábková Z, Sergedaite V, Siwińska N, Bajzert J, Pasak D, Chełmońska-Soyta A.Colic-related obstructions can reduced intestinal mucosa function and cause dysbiosis in horses, but it is unclear how defense barrier and secretory immunoglobulin A (SIgA) secretion is disrupted. Objective: The aim of the study is to evaluate the effect of severity of colic signs and treatments on fecal SIgA and fecal lactate in horses. Methods: Sixty-two client owned hospitalised horses with colic and eight healthy horses. Methods: Prospective clinical trial. Fecal samples were taken daily for 7 days. SIgA was analyzed using ELISA, and D/L-lactate measured with a commercial kit. Results: A...
Sjöberg I, Horn I, Ljungvall K, Andersen PH, Sternberg-Lewerin S.To investigate the influence of surgical antimicrobial prophylaxis (SAP) on complication rates and surgical site infections (SSI) in horses undergoing sutured castration in a hospital setting. Methods: Retrospective chart review of a convenience sample. Methods: A total of 220 colts and stallions admitted for sutured castration. Methods: Medical records of sutured castration were assessed for patient characteristics, perioperative and postoperative medications, and postoperative complications within 6 weeks after surgery. The effect of these variables on the occurrence of complications was a...
Heidenberger J, Reihs EI, Strauss J, Frauenlob M, Gültekin S, Gerner I, Tögel S, Ertl P, Windhager R, Jenner F, Rothbauer M.Osteoarthritis (OA) is a prevalent degenerative joint disorder characterized by cartilage degradation, chronic inflammation, and progressive joint dysfunction. Despite rising incidences driven by ageing and increasing obesity, potent treatments remain elusive, exacerbating the socioeconomic burden. OA pathogenesis involves an imbalance in extracellular matrix (ECM) turnover, mediated by inflammatory cytokines and matrix-degrading enzymes, leading to oxidative stress, chondrocyte apoptosis, and ECM degradation. Additionally, synovial inflammation (synovitis) plays a critical role in disease pro...
Akçay S, Gurkok-Tan T, Ekici S.Intense physical activity in endurance horses triggers complex immune and inflammatory responses, yet the molecular mechanisms underlying these adaptations remain unclear. This study investigated immune-related transcriptomic changes following a 160 km endurance ride, focusing on sex-based differences. Using a bioinformatics approach, differentially expressed genes (DEGs), pathways, microRNAs (miRNAs), and transcription factors (TFs) were analyzed before (T0) and after (T1) the ride. A protein-protein interaction (PPI) analysis was conducted to identify key regulatory genes. Pathway enrichment...
Conley HE, Davis KU, Adler KB, Lavoie JP, Sheats MK.Asthma is a chronic inflammatory airway disease that affects millions of people worldwide. Horses develop asthma spontaneously and serve as a relevant model for multiple phenotypes and endotypes of human asthma. In horses with equine asthma (EA), environmental organic dust triggers increased inflammatory cytokines, excess airway mucus, reversible bronchoconstriction, and airway inflammation. In horses with severe EA (sEA), lower airway inflammation is invariably neutrophilic, making sEA a potential model for severe neutrophilic asthma in humans. Alveolar macrophages (AM) and airway neutrophils...
Jimenez C, Hogan P, Belaghi R, Curtiss A.Epiglottitis is an uncommon upper airway pathology manifested endoscopically by mucosal oedema, reddening and thickening of the epiglottic mucosa. Literature on epiglottitis in horses is sparse. Objective: To describe the diagnosis, treatment and outcome of Thoroughbred and Standardbred racehorses diagnosed with epiglottitis at a single centre. A secondary objective is to demonstrate the efficacy of inhaled and topical anti-inflammatories for this condition. Methods: Retrospective case series. Methods: Medical records (2009-2023) were reviewed for racehorses treated for epiglottitis. Data coll...
Beck AA, Paz LB, Frank MI, Pereira RCF, De La Côrte FD.To evaluate the effect of IA injections of botulinum toxin type A (BoNT-A) in horses with chronic, naturally occurring distal tarsal osteoarthritis. Unassigned: 9 horses were selected after physical and radiographic assessments. Horses also underwent an objective lameness examination and were included if they had a hindlimb impact lameness (Pmin ≥ 3 mm), which positively responded (≥ 50%) to the tarsometatarsal and centrodistal joints' anesthetic block. Horses randomly received an intra-articular injection of BoNT-A or an equivalent volume of saline solution. Horses were reevaluated at pos...
Li X, Hu S, Yu Z, He F, Zhao X, Liu R.Nanoplastics (NPs) are emerging pollutants worldwide. Particularly worrisome is that although studies have reported that NPs can amplify the biotoxicity of environmental pollutants, the specific mechanism remains unclear. Here, we found that NPs, even without significant toxicity (cell survival: 99.11%), amplified the hepatocyte toxicity of Cd. Mechanistically, higher Cd uptake (Δ = 23.80%) combined with crucial intracellular desorption behavior of Cd loaded in NPs (desorption rate: 82.70%) were identified as prerequisites for NPs amplifying Cd cytotoxicity. As for toxigenic pathways, the inf...
Castanheira CIGD, Anderson JR, Clarke EJ, Hackl M, James V, Clegg PD, Peffers MJ.This study describes a novel technique to analyze the extracellular vesicle (EV)-derived microRNA (miRNA) crosstalk between equine chondrocytes and synoviocytes. Donor cells (chondrocytes, n = 8; synoviocytes, n = 9) were labelled with 5-ethynyl uridine (5-EU); EVs were isolated from culture media and incubated with recipient cells (chondrocytes [n = 5] were incubated with synoviocyte-derived EVs, and synoviocytes [n = 4] were incubated with chondrocyte-derived EVs). Total RNA was extracted from recipient cells; the 5-EU-labelled RNA was recovered and sequenced. Differential expression analysi...
Giorgio SD, Monti S, Palmieri V, Marino G, Napoli E, Vullo C, Catone G.A 3-year-old Quarter horse stallion with unilateral left cryptorchidism was referred for the absence of the left testis in the scrotal bursa and an enlarged right testis. The ultrasonographic examination revealed the presence of the left testis at the abdominal level. Two small hyperechogenic lines were observed running parallel and resembling a cylindrical cavitary foreign body, within a non-homogeneous area with blurred margins. The testis was removed by laparoscopy and macroscopically, the testis's cut section revealed the presence of two live adult nematodes emerging from 2 mm blood-filled...
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...
The objective of the present study was to investigate the influence of daily rhythms on the immune and inflammatory systems in horses, considering white blood cell count (WBCs), leukocyte subpopulations (neutrophils, basophils, eosinophils, lymphocytes, and monocytes), CD4+, and CD8+ lymphocyte populations, interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Ten Italian Saddle horses (7-12 years old, body weight 480 ± 30 kg) underwent blood sampling every 4 h over a 24-h period. The COSINOR method was used to identify rhythms and their parameters. A one-way ...
The inflammatory status in horses with gastric ulcers was monitored by two inflammatory biomarkers, S100A12 and adenosine deaminase (ADA), using saliva samples from healthy and horses with gastric ulcers. Two trials were developed: an experimental trial, in which gastric ulceration was induced in 8 horses by feed deprivation, and a clinical trial, in which 20 horses without any symptomatology and 37 with symptoms compatible with gastric ulcers were used. S100A12 and ADA levels were measured in the saliva samples of all horses using previously validated assays. In both trials, horses with gastr...
Giercuszkiewicz-Hecold B, Pajuelo D, Steczkiewicz Z, Cywinska A, Marycz K.Astaxanthin, a strong antioxidant carotenoid, has shown promising features in mitigating inflammation and oxidative stress and so that has been considered as a supplement for high-performance animals. In this study, we aimed to evaluate the effects of astaxanthin on oxidative stress, inflammation, and mitochondrial health in peripheral blood mononuclear cells (PBMC) isolated from Arabian racehorses. Horse-derived peripheral blood mononuclear cells exposed to hydrogen peroxide (H₂O₂) presented increased reactive oxygen species (ROS) accumulation and overexpression of pro-inflammatory cytoki...
Lam KP, Keys DA, McMullen RJ.To describe infracyanine green-based photodynamic therapy (InfraCG-PDT) and evaluate outcomes in horses with immune-mediated keratitis (IMMK). Methods: Medical records from 2014 to 2020 from the Equine Clinic Munich-Riem, Germany, and Auburn University Equine Ophthalmology Service identified horses diagnosed with IMMK following ophthalmic examination that had undergone InfraCG-PDT. Methods: Multiple intrastromal injections of EmunDo (InfraCG, A.R.C. Laser, Nuernberg, Germany) within an affected quadrant or the entire cornea were treated with diffuse diode laser energy (FOX A.R.C., Laser, Nuern...
Wright JP, Gray SM, Bishop RC.To describe and demonstrate the collection of abdominal fluid from a standing, sedated equine patient. Unassigned: 1 healthy university-owned animal was used for abdominocentesis demonstration. Images from various clinical cases from the University of Illinois Veterinary Teaching Hospital are shown. Unassigned: Under standing sedation, a 10 X 10-cm area is clipped and aseptically prepared on the most dependent portion of the abdomen to the right of midline. One to 2 mL of 2% lidocaine is instilled subcutaneously and into the abdominal musculature at the abdominocentesis site. A stab incision i...
Moore GE, Leatherwood JL, Glass KG, Arnold CE, Paris BL, Carter MM, George JM, Fontenot AB, Martinez RE, Franklin MA, Norton SA, Bradbery AN....The objective was to evaluate dietary fermentation product (SCFP) on joint inflammation and cartilage metabolism in exercising yearlings challenged with intra-articular lipopolysaccharide (LPS), hypothesizing dietary SCFP (TruEquineC, Diamond V Mills, Inc.) would ameliorate joint inflammation and increase cartilage metabolism. Thirty Quarter Horse yearlings were stratified by bodyweight (BW), age, sex, and randomly assigned to dietary treatments (n = 10/treatment): control (0), 46, or 92 mg/kg BW/d SCFP. Treatments were top-dressed to 1% BW/d concentrate void of added microbials. Horses ...
Serpa PBS, Bogers S, Byron C, Cardona G, Patton M.A 1-year-old American Quarter horse was presented with acute onset of right hind lameness. On physical examination, there was synovial effusion of the right tarsocrural joint. Synovial fluid cytology revealed a marked eosinophilic synovitis. Serology indicated evidence of acute and chronic infection with Borrelia burgdorferi, although PCR of the synovial fluid was negative. The filly was treated with phenylbutazone and oxytetracycline, and repeated synovial cytology indicated improvement. The filly was discharged with a prescription of minocycline for 30 days. Despite initial improvement, recu...
Carvalho IB, Branco S, Laranjo M, Queiroga MC, Bettencourt E.Uterine health is paramount to fertility in broodmares and for the success of a breeding project, and the Lusitano breed is no exception. This study aimed to characterize the mare uterine microbiota using practical clinical evaluation methods. Mares were examined by transrectal palpation and ultrasonography, followed by the collection of samples by one of three different techniques: uterine lavage, biopsy, or swab. The results of cytology, histology, microbiology, and antimicrobial susceptibility testing were recorded, and statistical analyses were performed. Inflammation was present in 42.2% ...
Toft K, Mardahl M, Hedberg-Alm Y, Anlén K, Tydén E, Nielsen MK, Honoré ML, Fromm B, Nielsen LN, Nejsum P, Thamsborg SM, Cirera S, Pihl TH.Non-strangulating intestinal infarctions (NSII) associated with Strongylus vulgaris infection and idiopathic peritonitis (IP) share similar clinical presentation but require different treatment approaches. Horses with NSII need surgical intervention, while idiopathic peritonitis cases can be successfully treated with antimicrobials. A correct diagnosis is thus crucial, but because the two diseases overlap in clinicopathological features, differentiation is difficult in clinical practice. MicroRNAs (miRNAs) are non-coding RNAs that exhibit measurable changes in abundance in tissues and circulat...
Birkmann K, Waldern N, Jucker S, Balaschitsch K, Zablotski Y, Fettelschoss-Gabriel A.Recurrent urticaria is common in horses. The pathophysiology is poorly understood and treatment options are limited. Often, only glucocorticoids are effective for controlling clinical signs, albeit with potential adverse effects. Studies investigating new treatments need a validated objective scoring system for the grading of skin lesions to assess response. Objective: The aims were to investigate inter- and intraobserver reliability of the Equine Urticaria Activity Score (EqUAS) for the grading of skin lesions in horses with recurrent urticaria, and to examine agreement between experienced an...
Rinnovati R, Spadari A, Malpighi A, Meistro F, Ralletti MV, Marcucci E, Tarasconi MA, Chiatto RL, Tommasa SD.Numerous treatment strategies have been proposed to manage osteoarthritis (OA) in sport horses. Carboxymethylcellulose (CMC), is used in veterinary medicine for various purposes. Objective: This study aimed to assess the efficacy of a CMC hydrogel in reducing clinical lameness in horses with OA affecting joint. The hypothesis was that intra-articular CMC would produce a sustained reduction in lameness compared to a control treatment. Methods: Thirty client-owned horses diagnosed with OA-related lameness in the metacarpophalangeal joint were enrolled. Horses were randomly assigned to two groups...
Miranda MR, Montano C, Golino V, de Chiara M, Del Prete C, Pepe G, De Biase D, Ciaglia T, Bertamino A, Campiglia P, Sommella E, Vestuto V, Pasolini MP.Wounds are common in equine practice, and often lead to complications such as infections, delayed healing and hypertrophic scarring, which can be costly and difficult to manage. Developing affordable and effective treatments has become an increasingly important focus in veterinary research. Equine advanced-platelet-rich fibrin plus (A-PRF+) demonstrates regenerative properties comparable to its human counterpart, but cellular-level investigations exploring its molecular mechanisms remain limited. This study aimed to investigate the in vitro effects of equine A-PRF + on primary fibroblast ...
Quam V.Inflammation plays a role in acute and chronic equine tendon/ligament injury; anti-inflammatories are often indicated. Local corticosteroids provide consistent and profound short-term effects on pain and inflammation across species. However, there is no demonstrated benefit in the long term, and complications can occur. Alternative biologic anti-inflammatory treatments are available and should be used in horses at risk of complications. Nonetheless, corticosteroids remain an affordable and effective anti-inflammatory that, with continued research, may be indicated on a case-by-case basis as pa...
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...
