In vivo studies involving horses refer to research conducted within living organisms to understand various biological processes, disease mechanisms, and therapeutic interventions in equine species. These studies provide insights into the physiological and pathological responses of horses under natural conditions. In vivo research encompasses a range of investigations, including pharmacokinetics, disease modeling, and the evaluation of treatment efficacy. It often involves the use of controlled environments to simulate real-life scenarios while observing the effects of specific variables on equine health. This page gathers peer-reviewed research articles and scholarly studies that explore the methodologies, findings, and implications of in vivo research in horses, contributing to the advancement of equine science and veterinary medicine.
Di Pietro R, Arroyo LG, Leclere M, Costa M.Bacterial imbalances are observed in intestinal diseases and fecal microbiota transplantation (FMT) has been used to restore the intestinal microbiota of horses. However, there is evidence that the current methods proposed for FMT in horses have limited efficacy. The objective of this study was to concentrate the bacteria present in the donor stool by centrifugation, and to test the effect in horses with antibiotic-induced dysbiosis. One healthy 11-year-old horse was selected as a fecal donor and 9 horses were given trimethoprim sulfadiazine (TMS) for 5 days to induce dysbiosis. Horses receive...
Terschuur JA, Coomer RPC, McKane SA.The objective of this study was to investigate the postoperative use of intrasynovial honey as an antimicrobial after treatment for synovial sepsis in horses. One colt and 2 mares were presented with acute lameness, with or without an associated wound. All 3 cases were initially managed with surgical endoscopic or tenoscopic debridement and lavage for treatment of different synovial structures. Collection of synovial fluid was consistent with synovial sepsis and this was diagnosed in each case. All horses subsequently underwent arthroscopic lavage under general anesthetic and intraarticular or...
Seewald LA, Sabino IG, Montney KL, Delco ML.To evaluate mitochondrial DNA (mtDNA) release from injured chondrocytes and investigate the utility of synovial fluid mtDNA concentration in early detection of posttraumatic osteoarthritis. We measured mtDNA release using four models of osteoarthritis: in vitro interleukin-1β stimulation of cultured equine chondrocytes, ex vivo mechanical impact of bovine cartilage explants, in vivo mechanical impact of equine articular cartilage, and naturally occurring equine intraarticular fracture. In our in vivo model, one group was treated with an intraarticular injection of the mitoprotective peptide S...
Daoualibi Y, Pereira AHB, Lima LR, Pool RR, Ubiali DG.Proliferative tenosynovitis (PT) is an inflammatory and proliferative disorder of the synovial membrane of the tendon sheath that is rare in animals. The histological alterations are characterized by multinodular neovascularization, with infiltration of histiocytic and multinucleated giant cells and haemosiderin deposition. We reviewed necropsy and biopsy records of horses submitted to the Setor de Anatomia Patológica of the Universidade Federal Rural do Rio de Janeiro from January 2017 to December 2020 to select cases of PT. We identified PT in three adult Brazilian Mangalarga Marchador hors...
Hunt J, Rice M, Henry T.A retrospective cohort study to describe a novel use of a mechanically retained, rigid obturator (RO) to manage maxillary and mandibular persistent pathologic oral communications (PPOCs). This study included 22 horses with PPOC with at least 6 months of follow-up after treatment with a RO. The RO was made with a flowable, bis-acryl-based composite resin. Medical records were analyzed, including case details, obtained imaging, surgical reports, and follow-up information. There were 10 horses that had follow-up examinations by the authors and 8 horses by the referring veterinarian; in 4 horses, ...
Colla S, Seabaugh KA, Zanotto GM, Selberg K.Techniques for local anesthesia of the tibial (TN) and superficial and deep fibular nerves (FNs) in horses are well established. Ultrasound-guided perineural blocks can identify the nerve location, reduce the anesthetic volume needed and avoid needle misplacement. The aim of this research was to compare the success of blind perineural injection technique (BLIND) to ultrasound-guided technique (USG). Fifteen equine cadaver hindlimbs were divided into two groups. Perineural injection of the TN and FNs was performed using a mixed solution of radiopaque contrast, saline and food dye. BLIND (n = ...
Cortez JV, Hardwicke K, Cuervo-Arango J, Grupen CG.The cloning of horses is a commercial reality, yet the availability of oocytes for cloned embryo production remains a major limitation. Immature oocytes collected from abattoir-sourced ovaries or from live mares by ovum pick-up (OPU) have both been used to generate cloned foals. However, the reported cloning efficiencies are difficult to compare due to the different somatic cell nuclear transfer (SCNT) techniques and conditions used. The objective of this retrospective study was to compare the in vitro and in vivo development of equine SCNT embryos produced using oocytes recovered from abatt...
Pozor MA, Benson SM, Macpherson ML, Kelleman AA.Transplantation of stem cells into dysfunctional testes is currently being investigated as a therapeutic option for men and stallions with advanced testicular degeneration. This series of "proof of concept" studies aimed to identify a safe and efficient method of inducing severe testicular degeneration to create an optimal equine recipient model for intratesticular stem cell transplantation (SCT). Two ex vivo and two in vivo experiments were conducted. At first, forty testes obtained from castrations were used to identify an effective therapeutic ultrasound (TUS) device and the protocol for ...
Bourebaba L, Serwotka-Suszczak A, Pielok A, Sikora M, Mularczyk M, Marycz K.Equine metabolic syndrome (EMS) is a multifactorial pathology gathering insulin resistance, low-grade inflammation and past or chronic laminitis. Among the several molecular mechanisms underlying EMS pathogenesis, increased negative insulin signalling regulation mediated by protein tyrosine phosphatase 1 B (PTP1B) has emerged as a critical axis in the development of liver insulin resistance and general metabolic distress associated to increased ER stress, inflammation and disrupted autophagy. Thus, the use of PTP1B selective inhibitors such as MSI-1436 might be considered as a golden therapeut...
Albanese V, Mereu M.Pelvic abscesses occur in horses of all ages and breeds. Although conservative management may be successful, surgical drainage may be necessary for larger abscesses or in case of secondary intestinal obstruction. The purpose of this report is to describe two cases of pelvic abscesses that were successfully drained using indwelling chest tubes, repeated lavages and targeted antibiotic treatment.
Donnelly CG, Johnson AL, Reed S, Finno CJ.Cervical vertebral compressive myelopathy (CVCM) and equine neuroaxonal dystrophy/degenerative myeloencephalopathy (eNAD/EDM) are leading causes of spinal ataxia in horses. The conditions can be difficult to differentiate, and there is currently no diagnostic modality that offers a definitive antemortem diagnosis. Objective: Evaluate novel proteomic techniques and machine learning algorithms to predict biomarkers that can aid in the antemortem diagnosis of noninfectious spinal ataxia in horses. Methods: Banked serum and cerebrospinal fluid (CSF) samples from necropsy-confirmed adult eNAD/EDM (...
Dos Santos GC, Di Filippo PA, da Fonseca LA, Quirino CR.The purpose of this study was to compare the extent of inflammation response in the middle carpal joints of healthy horses following intra-articular injection of 2% lidocaine, 0.5% bupivacaine, or 0.9% saline solution. The right middle carpal joint of 20 horses was injected with 5 mL of 0.5% bupivacaine (GB, n = 10) or 5 mL of 2% lidocaine (GL, n = 10). The left middle carpal joint of horses was used as a control (5 mL 0.9% saline). Serum and synovial fluid (SF) were aseptically collected before and at predetermined times after each injection. Serum and synovial fluid protein, albumin, tra...
Gandini M, Cerullo A, Gallo L, Iussich S, Minoli L, Giusto G.To describe a technique for a side-to-side jejunocecal anastomosis in horses using radiofrequency thermofusion (TF) of the intestines supported by a Cushing oversew and to compare this anastomosis to handsewn and stapled techniques. Methods: Ex vivo study. Methods: Intestinal tracts from 24 slaughtered horses. Methods: A radiofrequency device was used to perform a jejunocecal anastomosis (Group RFA). The construction time and bursting pressure of this construct were compared with those of a hand-sewn double layer (Group HS) and stapled anastomoses (Group ST) without oversew of the staple line....
Panizzi L, Dittmer KE, Vignes M, Doucet JS, Gedye K, Waterland MR, Rogers CW, Sano H, McIlwraith CW, Riley CB.Biomarkers for osteoarthritis (OA) in horses have been extensively investigated, but translation into clinical use has been limited due to cost, limited sensitivity, and practicality. Identifying novel biomarkers that overcome these limitations could facilitate early diagnosis and therapy. This study aimed to compare the concentrations of synovial fluid (SF) and plasma cell-free DNA (cfDNA) over time in control horses with those with induced carpal OA. Following an established model, unilateral carpal OA was induced in 9 of 17 healthy Thoroughbred fillies, while the remainder were sham-operate...
Onzere CK, Hulbert M, Sears KP, Williams LBA, Fry LM.Equine theileriosis, caused by and , leads to anemia, exercise intolerance, and occasionally, death. Theileriosis-free countries prohibit the importation of infected horses, resulting in significant costs for the equine industry. Imidocarb dipropionate is the only treatment for in the United States, but lacks efficacy against . The goal of this study was to assess the in vivo efficacy of tulathromycin and diclazuril against . Fourteen -infected horses were utilized. Six were treated with eight weekly 2.5 mg/kg doses of tulathromycin. Three were treated daily for eight weeks with 2.5 mg/kg di...
Vitale V, Nocera I, van Galen G, Sgorbini M, Conte G, Aliboni B, Verwilghen D.Transcutaneous abdominal ultrasonography using alcohol saturation is used in the diagnostic workup of a variety of conditions in horses. The duration of the examination and the amount of alcohol used in each case may vary depending on several factors. The aim of this study is to describe the breath alcohol test results obtained by veterinarians performing abdominal ultrasound on horses. Six volunteers were enrolled, after written consent, and a Standardbred mare was used for the whole study protocol. Each operator performed a total of 6 ultrasounds by pouring the ethanol solution from a jar or...
Soiluva J, Häyrinen L, Gangini G, Öistämö R, Gracia-Calvo LA, Raekallio MR.Traditional visual lameness assessment is subjective. Ethograms have been developed for evaluating pain and objective sensors to detect lameness. Heart rate (HR) and heart rate variability (HRV) have been used to evaluate stress and pain. The aim of our study was to compare subjective and behavioral lameness scores, a sensor system measuring movement asymmetry, HR, and HRV. We hypothesized that these measures would show related trends. In 30 horses, an inertial sensor system was used to measure movement asymmetries during trot in-hand. A horse was categorized as sound if each asymmetry was les...
Langreder N, Schäckermann D, Meier D, Becker M, Schubert M, Dübel S, Reinard T, Figge-Wegener S, Roßbach K, Bäumer W, Ladel S, Hust M.Insect bite hypersensitivity (IBH) is the most common allergic skin disease of horses. It is caused by insect bites of the Culicoides spp. which mediate a type I/IVb allergy with strong involvement of eosinophil cells. No specific treatment option is available so far. One concept could be the use of a therapeutic antibody targeting equine interleukin 5, the main activator and regulator of eosinophils. Therefore, antibodies were selected by phage display using the naïve human antibody gene libraries HAL9/10, tested in a cellular in vitro inhibition assay and subjected to an in vitro affinity...
Verhaar N, Hoppe S, Grages AM, Hansen K, Neudeck S, Kästner S, Mazzuoli-Weber G.α2 agonists are frequently used in horses with colic, even though they have been shown to inhibit gastrointestinal motility. The aim of this study was to determine the effect of dexmedetomidine on small intestinal in vitro contractility during different phases of ischaemia. Experimental segmental jejunal ischaemia was induced in 12 horses under general anaesthesia, and intestinal samples were taken pre-ischaemia and following ischaemia and reperfusion. Spontaneous and electrically evoked contractile activity of the circular and longitudinal smooth muscles were determined in each sample with a...
Persistent post-breeding induced endometritis (PPBIE) is considered a major cause of subfertility in mares. It consists of persistent or delayed uterine inflammation in susceptible mares. There are many options for the treatment of PPBIE, but in this study, a novel approach aimed at preventing the onset of PPBIE was investigated. Stallion semen was supplemented with extracellular vesicles derived from amniotic mesenchymal stromal cells (AMSC-EVs) at the time of insemination to prevent or limit the development of PPBIE. Before use in mares, a dose-response curve was produced to evaluate the eff...
Fisher M, Nebroski M, Davies J, Janzen E, Sullivan D, Lung O.The complete genome of a novel torque teno virus species (Torque teno equus virus 2 (TTEqV2) isolate Alberta/2018) was obtained by high-throughput sequencing (HTS) of nucleic acid extracted from the lung and liver tissue of a Quarter Horse gelding that died of nonsuppurative encephalitis in Alberta, Canada. The 2805 nucleotide circular genome is the first complete genome from the Mutorquevirus genus and has been approved as a new species by the International Committee on Taxonomy of Viruses. The genome contains several characteristic features of torque teno virus (TTV) genomes, including an OR...
Ishikawa Y, Sakai DM, Im JS, Zhang S, Reed RA, Quandt JE, Baldo CF, Walters B, Barletta M.To evaluate a regional anesthetic technique for blocking the abdominal midline in horses. Methods: Anatomical description and prospective, crossover, placebo-controlled, blinded study. Methods: Adult horses; two cadavers, six healthy animals. Methods: In stage 1, 0.5% methylene blue with 0.25% bupivacaine (0.5 mL kg) was injected using ultrasonography into the internal rectus abdominis sheath (RAS) of two cadavers with a one-point or two-point technique. The dye spread was described after the dissection of the abdomens. In stage 2, each horse was injected with 1 mL kg of 0.9% NaCl (treatment P...
Zamith Cunha R, Zannoni A, Salamanca G, De Silva M, Rinnovati R, Gramenzi A, Forni M, Chiocchetti R.The metacarpophalangeal joint undergoes enormous loading during locomotion and can therefore often become inflamed, potentially resulting in osteoarthritis (OA). There are studies indicating that the endocannabinoid system (ECS) modulates synovium homeostasis, and could be a promising target for OA therapy. Some cannabinoid receptors, which modulate proliferative and secretory responses in joint inflammation, have been functionally identified in human and animal synovial cells. Unassigned: To characterize the cellular distribution of the cannabinoid receptors 1 (CB1R) and 2 (CB2R), and the can...
Gebremedhn S, Gad A, Ishak GM, Menjivar NG, Gastal MO, Feugang JM, Prochazka R, Tesfaye D, Gastal EL.Innumerable similarities in reproductive cyclicity and hormonal alterations highlight the considerable utility of the mare to study aspects of follicular dynamics and reproductive function in view of the largely constricted, human research subjects. The bi-directional communication between the growing oocyte and the surrounding somatic cells embodies the hallmark of mammalian follicular development, partially mediated by extracellular vesicles (EVs) encapsulated with microRNAs (miRNAs) and present in the follicular fluid (FF). Here, we aimed to decipher the dynamics of the miRNAs in EVs from e...
Verhaar N, de Buhr N, von Köckritz-Blickwede M, Dümmer K, Hewicker-Trautwein M, Pfarrer C, Dengler F, Kästner S.Hypoxia inducible factors (HIF) are widely researched in human medicine for their role in different disease processes. The aim of this study was to investigate the expression and distribution of HIF in experimental small intestinal ischemia in the horse. Unassigned: In 14 horses under general anesthesia, segmental jejunal ischemia with 90% reduction in blood flow was induced. The horses were randomly divided into two groups of seven horses, one subjected to ischemic postconditioning (IPoC) by delayed reperfusion, and a control group (group C) undergoing undelayed reperfusion. Intestinal sample...
Burns TA, Watts MR, Belknap JK, van Eps AW.Supporting limb laminitis (SLL) is a complication of severe orthopedic disease in horses and is often life-limiting, yet the pathophysiology remains obscure. Objective: To investigate the role of digital lamellar inflammatory signaling in the pathophysiology of SLL using a model of unilateral weight bearing, hypothesizing that there would be evidence of lamellar inflammation in limbs subjected to the model. Methods: Thirteen healthy adult Standardbred horses were used for this study (11 geldings, 2 mares; mean age 6.5 ± 2.5 years; mean body weight 458.3 ± 32.8 kg). Methods: Randomized...
Palmisano M, Javsicas L, McNaughten J, Gamsjäger L, Renaud DL, Gomez DE.Anecdotal evidence suggests plasma transfusions increase serum amyloid A (SAA) concentrations in healthy neonatal foals making this marker of inflammation inappropriate for therapeutic decision making in such animals. Objective: Administration of hyperimmune fresh frozen plasma (FFP) increases SAA concentration in healthy foals and in foals with failure of transfer of passive immunity (FTPI). Methods: Eighty-six healthy foals. Methods: Prospective cohort study. Foals <24 hours of age receiving plasma transfusion for treatment of FTPI (serum immunoglobulin G [IgG] concentrations 8 g/L; nÂ...
Doll CU, Bohner M, Berner D, Buettner K, Horstmeier C, Winter K, Burk J.Low-field magnetic resonance imaging (MRI) has gained increasing importance to monitor equine tendon lesions. Comparing results between studies and cases is hampered, because image analysis approaches vary strongly. This study aimed to improve reliability, comparability and time efficiency of quantitative MRI image analysis. Unassigned: Induced tendon lesions were studied over a 24-week period with 10 follow-up MRI examinations. Signal intensities (SIs) of tendons, tendon lesions, cortical bone and background, as well as lesion cross-sectional areas (CSAs) were measured. Lesion SI standardisat...
Castro-Cuellar G, Cremer J, Queiroz-Williams P, Knych HK, Leise BS.The objective of this study was to describe the pharmacokinetics of intra-articular (IA) administered buprenorphine in horses with lipopolysaccharide (LPS)-induced synovitis. Radiocarpal synovitis was induced in six healthy adult horses with the IA injection of LPS (0.5 ng/joint) on two occasions in a randomized cross-over design. Treatments (IA buprenorphine (IAB) at 5 μg/kg plus intravenous saline; and intravenous buprenorphine (IVB) at 5 μg/kg plus IA saline) were administered 4 h following LPS injection. Concentrations of buprenorphine were assessed in plasma and synovial fluid (SF) ...
Koch DW, Schnabel LV, Reynolds J, Berry CR.Limb lymphedema in horses can be debilitating and painful. Pneumatic compression therapy has shown significant benefits for people suffering from lymphedema. The objective of this study was to determine the effect of a novel, equine-specific pneumatic compression device on the lymphatic flow of healthy horse forelimbs as determined by Tc-99m sulfur colloid lymphoscintigraphy. Methods: 6 healthy Thoroughbreds. Methods: In a randomized crossover design, horses underwent bilateral forelimb lymphoscintigraphy following subcutaneous injection of Tc-99m sulfur colloid at the coronary band as untreat...
Love CC.Sperm quality has an important role in determining fertility. Although there have been numerous studies to document the relationship between sperm quality and fertility, the methods of determining this association and conclusions vary. In the present study, computer-assisted sperm analysis (CASA) was used for evaluation of sperm motility, and differential interference contrast (DIC) microscopy was used for evaluating sperm morphologic features of breeding stallions. Fertility was measured using three endpoints: seasonal pregnancy rate (PR), percent pregnant/cycle (PC), and percent pregnant/fir...
Westgate SJ, Percival SL, Knottenbelt DC, Clegg PD, Cochrane CA.Horse wounds have a high risk of becoming infected due to their environment. Infected wounds harbour diverse populations of microorganisms, however in some cases these microorganisms can be difficult to identify and fail to respond to antibiotic treatment, resulting in chronic non-healing wounds. In human wounds this has been attributed to the ability of bacteria to survive in a biofilm phenotypic state. Biofilms are known to delay wound healing, principally due to their recalcitrance towards antimicrobial therapies and components of the innate immune response. This study describes the presenc...
Nawrocka D, Kornicka K, Åšmieszek A, Marycz K.Equine Metabolic Syndrome (EMS) is a steadily growing life-threatening endocrine disorder linked to insulin resistance, oxidative stress, and systemic inflammation. Inflammatory microenvironment of adipose tissue constitutes the direct tissue milieu for various cell populations, including adipose-derived mesenchymal stromal cells (ASCs), widely considered as a potential therapeutic cell source in the course of the treatment of metabolic disorders. Moreover, elevated oxidative stress induces inflammation in intestinal epithelial cells (IECs)-the first-line cells exposed to dietary compounds. In...
Takahashi T, Yawata M, Raudsepp T, Lear TL, Chowdhary BP, Antczak DF, Kasahara M.In rodents, the Ly49 family encodes natural killer (NK) receptors interacting with classical MHC class I molecules, whereas the corresponding receptors in primates are members of the killer cell immunoglobulin-like receptor (KIR) family. Recent evidence indicates that the cattle, domestic cat, dog, and pig have a single LY49 and multiple KIR genes, suggesting that predominant NK receptors in most non-rodent mammals might be KIR. Here, we show that the horse has at least six LY49 genes, five with an immunoreceptor tyrosine-based inhibition motif (ITIM) and one with arginine in the transmembrane...
Witkowska-Piłaszewicz OD, Żmigrodzka M, Winnicka A, Miśkiewicz A, Strzelec K, Cywińska A.Serum amyloid A (SAA) is the major acute phase protein in horses. It is produced during the acute phase response (APR), a nonspecific systemic reaction to any type of tissue injury. In the blood of healthy horses, SAA concentration is very low, but it increases dramatically with inflammation. Due to the short half-life of SAA, changes in its concentration in blood closely reflect the onset of inflammation and, therefore, measurement of SAA useful in the diagnosis and monitoring of disease and response to treatment. Increases in SAA concentration have been described in equine digestive, reprodu...
Crisman MV, Scarratt WK, Zimmerman KL.Activation of the host response to infection, the "acute-phase response," is a highly organized physiologic reaction that includes changes in concentrations of plasma acute-phase proteins (APPs). The APPs are increasingly being used as markers for prognosis and monitoring response to therapy along with general determinants of equine health. Use of APPs in veterinary medicine is becoming more widespread as more commercial diagnostic kits are being validated. This article reviews the salient features of APPs and examines their current application and potential utility in equine inflammatory diso...
Leemans B, Gadella BM, Stout TA, De Schauwer C, Nelis H, Hoogewijs M, Van Soom A.In contrast to man and many other mammalian species, conventional in vitro fertilization (IVF) with horse gametes is not reliably successful. The apparent inability of stallion spermatozoa to penetrate the zona pellucida in vitro is most likely due to incomplete activation of spermatozoa (capacitation) because of inadequate capacitating or fertilizing media. In vivo, the oviduct and its secretions provide a microenvironment that does reliably support and regulate interaction between the gametes. This review focuses on equine sperm-oviduct interaction. Equine sperm-oviduct binding appears to be...
Pomar FJ, Teerds KJ, Kidson A, Colenbrander B, Tharasanit T, Aguilar B, Roelen BA.The occurrence of pregnancies and births after embryo transfer (ET) of in vivo produced embryos is generally more successful compared to that of embryos produced in vitro. This difference in ET success has been observed when embryos of morphological equal (high) quality were used. The incidence of apoptosis has been suggested as an additional criterion to morphological embryo evaluation in order to assess embryo quality and effectively predict embryo viability. In this study, equine, porcine, ovine, caprine and bovine in vivo and in vitro produced morphologically selected high quality (grade-I...
Mihm M, Evans AC.The selection of a single ovarian follicle for further differentiation and finally ovulation is a shared phenomenon in monovulatory species from different phylogenetic classes. The commonality of dominant follicle (DF) development leads us to hypothesize that mechanisms for DF selection are conserved. This review highlights similarities and differences in follicular wave growth between cows, mares and women, addresses the commonality of the transient rises in FSH concentrations, and discusses the follicular secretions oestradiol and inhibin with their regulatory roles for FSH. In all three spe...
Nemoto M, Oue Y, Morita Y, Kanno T, Kinoshita Y, Niwa H, Ueno T, Katayama Y, Bannai H, Tsujimura K, Yamanaka T, Kondo T.Recently, outbreaks associated with equine coronavirus (ECoV) have occurred in Japan and the United States. While ECoV is likely to be pathogenic to horses, it has not been shown that experimental inoculation of horses with ECoV produces clinical signs of disease. In this study, we inoculated three Japanese draft horses with an ECoV-positive diarrheic fecal sample to confirm infection after inoculation and to investigate the clinical course and virus shedding patterns of ECoV. Virus neutralization tests showed that all three horses became infected with ECoV. Two of the three horses developed c...
Chambers TM, Quinlivan M, Sturgill T, Cullinane A, Horohov DW, Zamarin D, Arkins S, GarcÃa-Sastre A, Palese P.Three previously described NS1 mutant equine influenza viruses encoding carboxy-terminally truncated NS1 proteins are impaired in their ability to inhibit type I IFN production in vitro and are replication attenuated, and thus are candidates for use as a modified live influenza virus vaccine in the horse. Objective: One or more of these mutant viruses is safe when administered to horses, and recipient horses when challenged with wild-type influenza have reduced physiological and virological correlates of disease. Methods: Vaccination and challenge studies were done in horses, with measurement ...
Christoffersen M, Woodward E, Bojesen AM, Jacobsen S, Petersen MR, Troedsson MH, Lehn-Jensen H.The objective of the study was to evaluate the gene expression of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, tumor necrosis factor [TNF]-α, IL-1 receptor antagonist [ra] and serum amyloid A (SAA) in endometrial tissue and circulating leukocytes in response to uterine inoculation of 105 colony forming units (CFU) Escherichia coli in mares. Before inoculation, mares were classified as resistant or susceptible to persistent endometritis based on their uterine inflammatory response to infusion of 109 killed spermatozoa and histological assessment of the endometrial quality. ...
Thorpe CT, Karunaseelan KJ, Ng Chieng Hin J, Riley GP, Birch HL, Clegg PD, Screen HR.Although the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the energetic cost of locomotion. To maximise energy storage and return, energy-storing tendons need to be more extensible and elastic than tendons with a purely positional function. These properties are conferred in part by a specialisation of a specific compartment of the tendon, the interfascicular matrix, which enables sliding and recoil between adjacent fascicles. However, the composition of the interfascicular matr...
Brooks SA, Bailey E.Sabino (SB) is a white spotting pattern in the horse characterized by white patches on the face, lower legs, or belly, and interspersed white hairs on the midsection. Based on comparable phenotypes in humans and pigs, the KIT gene was investigated as the origin of the Sabino phenotype. In this article we report the genetic basis of one type of Sabino spotting pattern in horses that we call Sabino 1, with the alleles represented by the symbols SB1 and sb1. Transcripts of KIT were characterized by reverse transcriptase polymerase chain reaction (RT-PCR) and sequencing cDNA from horses with the g...
Perkins GA, den Bakker HC, Burton AJ, Erb HN, McDonough SP, McDonough PL, Parker J, Rosenthal RL, Wiedmann M, Dowd SE, Simpson KW.Little is known about the gastric mucosal microbiota in healthy horses, and its role in gastric disease has not been critically examined. The present study used a combination of 16S rRNA bacterial tag-encoded pyrosequencing (bTEFAP) and fluorescence in situ hybridization (FISH) to characterize the composition and spatial distribution of selected gastric mucosal microbiota of healthy horses. Biopsy specimens of the squamous, glandular, antral, and any ulcerated mucosa were obtained from 6 healthy horses by gastroscopy and from 3 horses immediately postmortem. Pyrosequencing was performed on bio...
Schauer SN, Sontakke SD, Watson ED, Esteves CL, Donadeu FX.Previous evidence from in vitro studies suggests specific roles for a subset of miRNAs, including miR-21, miR-23a, miR-145, miR-503, miR-224, miR-383, miR-378, miR-132, and miR-212, in regulating ovarian follicle development. The objective of this study was to determine changes in the levels of these miRNAs in relation to follicle selection, maturation, and ovulation in the monovular equine ovary. In Experiment 1, follicular fluid was aspirated during ovulatory cycles from the dominant (DO) and largest subordinate (S) follicles of an ovulatory wave and the dominant (DA) follicle of a mid-cycle...
Maury W.In vivo, equine infectious anemia virus (EIAV) replicates in tissues rich in macrophages, and it is widely believed that the tissue macrophage is the principal, if not sole, cell within the host that replicates virus. No viral replication has been detected in circulating peripheral blood monocytes. However, proviral DNA can be detected in these cells, and monocytes may serve as a reservoir for the virus. In this study, an in vitro model was developed to clarify the role of monocyte maturation in regulating EIAV expression. Freshly isolated, nonadherent equine peripheral blood monocytes were in...
Colenbrander B, Gadella BM, Stout TA.Pregnancy rates in managed horse populations depend on the innate fertility of the mares and stallions involved and on the quality of breeding management. Of course, because a single stallion usually mates many mares, stallion fertility is a critical factor in the overall success of a breeding program. Unfortunately, accurate evaluation of stallion fertility per se requires a large number of normal mares to be mated and is necessarily retrospective. Rather, the ideal is to predict fertility in advance of the stallion's breeding career, and this is currently attempted by way of a thorough physi...
Hendrickson DA, Nixon AJ, Grande DA, Todhunter RJ, Minor RM, Erb H, Lust G.Cartilage resurfacing by chondrocyte implantation, with fibrin used as a vehicle, was examined in large (12 mm) full-thickness articular cartilage defects in horses. Articular chondrocytes, isolated from a 9-day-old foal, were mixed with fibrinogen and injected with thrombin, in a 1:1 mixture, into 12 mm circular defects on the lateral trochlea of the distal femur of eight normal horses. The contralateral femoropatellar (knee) joint served as a control in which the defect was left empty. Synovial fluid from the femoropatellar joints was sampled on days 0, 4, 7, 30, 120, and 240 postoperatively...
Schoster A, Weese JS, Guardabassi L.The gastrointestinal microbiota is extremely important for human and animal health. Investigations into the composition of the microbiota and its therapeutic modification have received increasing interest in human and veterinary medicine. Probiotics are a way of modifying the microbiota and have been tested to prevent and treat diseases. Probiotics are proposed to exert their beneficial effects through various pathways. Production of antimicrobial compounds targeting intestinal pathogens, general immune stimulation, and colonization resistance are among these mechanisms. Despite widespread ava...
de Grauw JC, van de Lest CH, Brama PA, Rambags BP, van Weeren PR.Meloxicam is a commonly used nonsteroidal anti-inflammatory drug in equine practice, but little is known about its in vivo effects on joint inflammation and cartilage turnover. Objective: To study the effects of meloxicam on biomarkers of inflammation, matrix metalloproteinase (MMP) activity, and cartilage biomarkers in joints with experimental synovitis. Methods: In a 2-period cross-over study, synovitis was induced at T = 0 h in the L or R intercarpal joint of 6 horses by intraarticular injection of 0.5 ng lipopolysaccharide (LPS). Horses received once daily meloxicam (0.6 mg/kg bwt per os) ...
Kotilainen T, Huhtinen M, Katila T.The objective of this study was to investigate the inflammatory reaction induced in the equine uterus by insemination with fresh and frozen semen. Eleven groups (6 to 8 mares per group) were studied during 2 breeding seasons. The mares were inseminated using raw semen, frozen semen, extended fresh and frozen semen, concentrated fresh semen, seminal plasma and seminal extenders only. One group was bred naturally. Six hours after insemination, the uteri were flushed with 50 ml of phosphate-buffered saline (PBS). Seventeen out of 104 samples (16%) exhibited slight bacterial growth. Neutrophil con...
Alghamdi AS, Lovaas BJ, Bird SL, Lamb GC, Rendahl AK, Taube PC, Foster DN.Bovine semen is naturally deposited in the vagina and spermatozoa migrate through the cervix into the uterus leaving the bulk of seminal plasma (SP) behind. In equine, both spermatozoa and SP are deposited directly in the uterus and SP reduces sperm binding to neutrophils and prevents the formation of DNA-based neutrophil extracellular traps (NETs). We investigated the role of bovine SP on sperm-neutrophil binding using the four most common bovine semen extenders. Contrary to equine, bovine spermatozoa removed from SP had low binding to neutrophils for up to 3h, but as little as 10% SP increas...
Böer U, Lohrenz A, Klingenberg M, Pich A, Haverich A, Wilhelmi M.Decellularized equine carotid arteries (dEAC) may represent a reasonable alternative to alloplastic materials in vascular replacement therapy. Acellularity of the matrix is standardly evaluated by DNA quantification what however may not record sufficiently the degree of matrix immunogenicity. Thus, our aim was to analyze dEAC with a low DNA content for residual cellular proteins. A detergent-based decellularization protocol including endonuclease treatment resulted in dEAC with 0.6 ± 0.15 ng DNA/mg dry weight representing 0.33 ± 0.14% of native tissue DNA content. In contrast, when matrices ...
Wieringa R, de Vries AA, Rottier PJ.Equine arteritis virus (EAV) is an enveloped, positive-stranded RNA virus belonging to the family Arteriviridae of the order NIDOVIRALES: Six transmembrane proteins have been identified in EAV particles: the nonglycosylated membrane protein M and the glycoprotein GP(5) (previously named G(L)), which occur as disulfide-bonded heterodimers and are the major viral envelope proteins; the unglycosylated small envelope protein E; and the minor glycoproteins GP(2b) (formerly designated G(S)), GP(3), and GP(4). Analysis of the appearance of the GP(2b), GP(3), and GP(4) proteins in viral particles by g...
Sabeur K, Ball BA.Reactive oxygen species (ROS) play an important role in normal sperm function, and spermatozoa possess specific mechanisms for ROS generation via an NAD(P)H-dependent oxidase. The aim of this study was to identify the presence of an NADPH oxidase 5 (NOX5) in equine testis and spermatozoa. The mRNA of NOX5 was expressed in equine testis as detected by northern blot probed with human NOX5 cDNA and by RT-PCR. Immunoblotting with affinity purified alpha-NOX5 revealed one major protein in equine testis and other tissues. Immunolocalization of NOX5 showed labeling over the rostral sperm head with so...
Blackmore TM, Dugdale A, Argo CM, Curtis G, Pinloche E, Harris PA, Worgan HJ, Girdwood SE, Dougal K, Newbold CJ, McEwan NR.The horse, as a hindgut fermenter, is reliant on its intestinal bacterial population for efficient diet utilisation. However, sudden disturbance of this population can result in severe colic or laminitis, both of which may require euthanasia. This study therefore aimed to determine the temporal stability of the bacterial population of faecal samples from six ponies maintained on a formulated high fibre diet. Bacterial 16S rRNA terminal restriction fragment length polymorphism (TRFLP) analyses of 10 faecal samples collected from 6 ponies at regular intervals over 72 hour trial periods identifie...
Mancini IAD, Schmidt S, Brommer H, Pouran B, Schäfer S, Tessmar J, Mensinga A, van Rijen MHP, Groll J, Blunk T, Levato R, Malda J, van Weeren PR.Recent research has been focusing on the generation of living personalized osteochondral constructs for joint repair. Native articular cartilage has a zonal structure, which is not reflected in current constructs and which may be a cause of the frequent failure of these repair attempts. Therefore, we investigated the performance of a composite implant that further reflects the zonal distribution of cellular component both in vitro and in vivo in a long-term equine model. Constructs constituted of a 3D-printed poly(ϵ-caprolactone) (PCL) bone anchor from which reinforcing fibers protruded into ...