Experimental methods in equine research encompass a variety of techniques and procedures used to investigate physiological, behavioral, and health-related aspects of horses. These methods are designed to collect data that can enhance the understanding of equine biology and inform veterinary practices. Common experimental approaches include controlled trials, observational studies, and laboratory-based experiments. Techniques may involve the use of non-invasive imaging, biochemical assays, and physiological monitoring to assess parameters such as metabolic function, locomotion, and disease progression. This page compiles peer-reviewed research studies and scholarly articles that explore the application, development, and evaluation of experimental methods in the study of equine science.
Cohen ND, Kahn SK, Bordin AI, Gonzales GM, da Silveira BP, Bray JM, Legere RM, Ramirez-Cortez SC.Intragastric administration of virulent Rhodococcus equi protects foals against subsequent experimental intrabronchial (IB) infection, but it is unknown whether R. equi naturally ingested by foals contributes to their susceptibility to pneumonia. Objective: Fecal concentration of virulent R. equi before IB infection with R. equi is positively associated with protection from pneumonia in foals. Methods: Twenty-one university-owned foals. Methods: Samples were collected from experimental studies. Five foals were gavaged with live, virulent R. equi (LVRE) at age 2 and 4 days; the remaining 16 f...
Sreenivasan CC, Uprety T, Reedy SE, Temeeyasen G, Hause BM, Wang D, Li F, Chambers TM.Antibodies to influenza D virus (IDV) have been detected in horses, but no evidence of disease in the field has been reported. To determine whether IDV is infectious, immunogenic, and pathogenic in horses, four 2-year-old horses seronegative for both influenza A (H3N8) and D viruses were intranasally inoculated with 6.25 × 107 TCID50/animal of D/bovine/California/0363/2019 (D/CA2019) virus, using a portable equine nebulizer system. Horses were observed daily for clinical signs including rectal temperature, nasal discharge, coughing, lung sounds, tachycardia, and tachypnea. No horses exhibited...
Rankins EM, Manso Filho HC, Malinowski K, McKeever KH.Horses' muscular tension during acute stress remains unexplored. Our aim was to assess muscular, behavioral, cortisol, and hematocrit responses to social isolation (ISO), novel object exposure (NOV), and sham clipping (CLIP). Altered stress responses were expected. Eight mature Standardbred horses (four mares and four geldings) were exposed to acute stressors and a control period (CON) in a balanced, replicated 4×4 Latin Square experimental design with 3 min treatment periods and 10 min washout periods. Surface electromyography collected from the masseter, brachiocephalas, cervical trapeziu...
Cawley A, Keen B, Tou K, Elbourne M, Keledjian J.The concept of biomarker measurements in the form of a ratio has not been explored in detail. This is surprising considering the current and future potential for biomarkers incorporating endogenous reference compounds (ERCs) in a range of fields. A selection of these relating to clinical and forensic applications, human antidoping, equine antidoping and veterinary residues are discussed.
Hopster K, Watkins AR, Hurcombe SD.To compare the antinociceptive effects of morphine administered via cervical epidural catheter to intravenously administered morphine using a thermal threshold (TT) testing model in healthy adult horses. Methods: Prospective, randomized, blinded experimental study. Methods: A total of six university-owned adult horses. Methods: Horses were instrumented with a cervical (C1-C2) epidural catheter and TT testing device with probes at withers and thoracic limb coronary bands. All horses underwent three TT testing cycles including cervical epidural morphine administration (treatment EpiM; 0.1 mg kg-...
Regenerative medicine applied to skin lesions is a field in constant improvement. The use of biomaterials with integrin agonists could promote cell adhesion increasing tissue repair processes. The aim of this pilot study was to analyze the effect of an α4β1 integrin agonist on cell adhesion of equine adipose tissue (AT) and Wharton's jelly (WJ) derived MSCs and to investigate their adhesion ability to GM18 incorporated poly L-lactic acid (PLLA) scaffolds. Adhesion assays were performed after culturing AT- and WJ-MSCs with GM18 coating or soluble GM18. Cell adhesion on GM18 containing PLLA sc...
Fowler AL, Hayes SH, Crum AD, Lawrence LM.Titanium dioxide has been used as a marker for determining diet digestibility indirectly, but some authors have expressed difficulty in measuring TiO2 concentrations in fecal material. We developed an accurate and precise method to determine TiO2 concentrations in equine feces. The method includes dry-ashing samples, digestion with (NH4)2SO4 in concentrated sulfuric acid, followed by the addition of H2O2 to produce a yellow to orange color that can be read spectrophotometrically. Accuracy was tested by spike recovery, and precision was tested by examining the coefficient of variation (CV) betw...
Enke N, Brinkmann L, Südekum KH, Tholen E, Gerken M.Horses lose high amounts of Na through excessive sweating. These fluid losses can often not be replaced completely by voluntary water intake, requiring saline solutions as rehydration therapy to regain electrolyte balance. The experiment aimed to evaluate the sensitivity and tolerance of Shetland ponies towards different Na concentrations in their drinking water and contained three phases: (1) control: only fresh water provided; (2) pairwise-preference test: choice between fresh water and saline solution with stepwise increasing sodium chloride (NaCl) concentration (0.25%, 0.5%, 0.75%, 1.0%, 1...
Samimi AS, Molaei MM, Azari O, Rezaei MA, Hashemian A.The present study aimed to compare the sedative and analgesic effects of caudal epidural administration of lidocaine alone or in combination with four different α-adrenergic agonists in Mediterranean miniature donkeys. A total of ten clinically healthy (five males and five females) Mediterranean miniature donkeys with an age of 5 ± 1 years, a weight of 100 ± 2 kg and a height at the withers of 0.8 ± 0.06 m (mean ± standard deviation) were used in experimental, crossover (Latin square), randomized, and blinded study. Animals were assigned to five treatment groups including lidocaine alone ...
Janczarek I, Wiśniewska A, Tkaczyk E, Wnuk-Pawlak E, Kaczmarek B, Liss-Szczepanek M, Kędzierski W.Cooling a horse after intensive exercise under hot conditions is commonly recommended. The study aimed to analyze changes in the rectal and surface temperature of the horses subjected to various water cooling treatments. This followed medium-intensity exercise performed by leisure horses under moderate air temperature. The experiment involved a control group without water application, and three variants of water cooling applied to 19 warmblood geldings after medium-intensity effort. Cooling of lower, upper, and lower and upper body parts was performed. In each variant, the rectal and body surf...
Spriet M, Edwards L, Arndt S, Wilson SS, Galuppo LD, Stepanov P, Beylin D.A positron emission tomography (PET) scanner, with an openable ring of detectors, was specifically designed to image the distal limb of standing horses. The goals of this prospective, preclinical, experimental, methods comparison study were to validate the safety of the scanner, assess image quality, and optimize scanning protocols. Six research horses were imaged three times (twice standing, once anesthetized) and six horses in active race training were imaged once under standing sedation. Multiple scans of both front fetlocks were obtained with different scan durations and axial fields of vi...
Peeters MWJ, Thursby JJ, Watson HE, Berner D.Palmaroproximal-palmarodistal oblique (PaPr-PaDiO) radiographs are regularly obtained for a full evaluation of the navicular bone (NB). Despite their routine use, different acquisition techniques are described. Objective: To determine optimal foot placement and beam angle for obtaining PaPr-PaDiO views. Methods: In vitro experiment. Methods: A convenience sample of 26 disarticulated forelimbs were placed in six different positions using a leg press to mimic the weight-bearing position. In each position, navicular PaPr-PaDiO images were obtained with eight different beam angles. The resulting 1...
Nielsen MK, von Samson-Himmelstjerna G, Kuzmina TA, van Doorn DCK, Meana A, Rehbein S, Elliott T, Reinemeyer CR.This guideline have been developed to assist in the design, execution, and interpretation of studies to assess the efficacy of anthelmintic drugs against internal parasites of equines, including nematodes, cestodes, and larval instars of Gasterophilus spp. The design and execution of critical and controlled studies are outlined, and their advantages and disadvantages are discussed. Unique considerations for specific target parasites are included. Information is also provided on selection of animals, procedures for randomization, housing, feeding, dosage titration, dosage confirmation and field...
Pressanto MC, Pascoletti G, Perkins JD, Zanetti EM, Beccati F, Santalucia V, Pepe M.To validate the use of a polyblend tape suture in equine laryngoplasty (PL). Methods: Experimental study. Methods: Thirty-two cadaveric larynges. Methods: Each larynx was randomly assigned to 1 of 4 groups: PL with polyblend tape suture (TigerTape), without (TT) or with a cannula (TTC) in the muscular process of the arytenoid cartilage, and PL with polyester suture (Ethibond), without (EB) or with a cannula (EBC). Construct stiffness, total migration, creep, and drift values were measured after 3000 cycles. The specimens were then loaded to failure to assess their residual properties: load a...
Abd El-Rahman SS, Amer MS, Hassan MH, Fahmy HM, Shamaa AA.Lyophilized equine platelet derived growth factors (LGF) is a novel advanced platelet rich protein growth factor. It has been successfully applied in various fields of regenerative medicine to treat a variety of inflammatory and degenerative musculoskeletal conditions. Our study aimed to evaluate the efficacy of intraarticularly injected LGF for the remedy of articular cartilage injury, commonly characterized by progressive pain and loss of joint function in osteoarthritic rabbits. Full-thickness cylindrical cartilage defects were generated in both femoral condylar articular surfaces in twenty...
Moreno CR, Santschi EM, Younkin JT, Larson RL, Litsky AS.To determine the failure method of simulated equine medial femoral condyle (MFC) subchondral bone defects under compression and the influence of screw placement on failure resistance. Methods: In vitro study. Methods: Composite disks (CD) simulating the moduli of yearling bone in the MFC. Methods: Four CD conditions were tested, all with a 12.7 mm void (n = 6 per condition): intact (no void), void only, void with a 4.5 mm screw placed in neutral fashion, and void with a 4.5 mm screw placed in lag fashion. Composite disks of each condition were tested under monotonic compression to 6000...
Moorman VJ, Pezzanite LM, Griffenhagen GM.To compare the efficacy and duration of action for perineural analgesia with liposomal bupivacaine (LB) versus bupivacaine hydrochloride (BHCl) in a sole-pressure induced model of forelimb lameness in horses. Methods: 6 healthy adult research horses. Methods: In 1 randomly assigned forelimb, grade 3/5 lameness was induced by use of a sole-pressure lameness model. Objective lameness (vector sum [VS]) was determined with an inertial sensor system at 0, 1, 6, and 24 hours after lameness induction to evaluate the model. Mechanical nociceptive thresholds (MNTs) and objective lameness (VS and force ...
Schulze N, Werpy N, Gernhardt J, Fritsch G, Hildebrandt T, Vanderperren K, Klopfleisch R, Ben Romdhane R, Lischer C, Ehrle A.Dynamic computed tomography (CT) imaging has been introduced in human orthopaedics and is continuing to gain popularity. With dynamic CT, video sequences of anatomical structures can be evaluated in motion. Objective: To investigate the feasibility of dynamic CT for diagnostic imaging of the equine cervical articular process joints (APJs) and to give a detailed description of the APJ movement pattern. Methods: Descriptive cadaver imaging. Methods: Cervical specimens of twelve Warmblood horses were included. A custom-made motorised testing device was used to position and manipulate the neck spe...
Cheng X, Kong X, Fan Y, Wang X, Li Z, Wu H.Generally, adequate motor coordination (MC) ability is one among the critical factors for the overall development of children. In this paper, we have thoroughly analyzed the effects of equine-assistant activity (EAA) training on MC in children. For this purpose, MC test, specifically for children, was used to the Körperkoordinationstest für Kinder (KTK), and a total of 100 children, particularly those in 8 to 10 age, were equally separated into equine-assistant activity group (EAAG) and control group (CG), respectively. The EAAG group has attended a 14-week EAA training program, while the CG...
Hagen A, Holland H, Brandt VP, Doll CU, Häußler TC, Melzer M, Moellerberndt J, Lehmann H, Burk J.Platelet lysate (PL) is an attractive platelet-based therapeutic tool and has shown promise as xeno-free replacement for fetal bovine serum (FBS) in human and equine mesenchymal stromal cell (MSC) culture. Here, we established a scalable buffy-coat-based protocol for canine PL (cPL) production (n = 12). The cPL was tested in canine adipose MSC (n = 5) culture compared to FBS. For further comparison, equine adipose MSC (n = 5) were cultured with analogous equine PL (ePL) or FBS. During canine blood processing, platelet and transforming growth factor-β1 concentrations increased ( < 0.05 and < ...
Potter SJ, Bamford NJ, Baskerville CL, Harris PA, Bailey SR.Ponies and some horse breeds such as Andalusians exhibit an 'easy keeper' phenotype and tend to become obese more readily than other breeds such as Standardbreds. Various hypotheses have been proposed, including differences in appetite or metabolic efficiency. This study aimed to investigate the effect of breed on nutrient digestibility. Ponies, Standardbreds and Andalusian horses were adapted to consuming either a control fibre-based diet ( = 9), a hypercaloric cereal-rich diet ( = 12) or a hypercaloric fat-rich diet ( = 12) over 20 weeks. Total faecal collection was performed over 24 h to de...
Leemans B, Bromfield EG, Stout TAE, Vos M, Van Der Ham H, Van Beek R, Van Soom A, Gadella BM, Henning H.We describe the development of two methods for obtaining confluent monolayers of polarized, differentiated equine oviduct epithelial cells (EOEC) in Transwell inserts and microfluidic chips. EOECs from the ampulla were isolated post-mortem and seeded either (1) directly onto a microporous membrane as differentiated EOECs (direct seeding protocol) or (2) first cultured to a confluent de-differentiated monolayer in conventional wells, then trypsinized and seeded onto a microporous membrane (re-differentiation protocol). Maintenance or induction of EOEC differentiation in these systems was achiev...
Macêdo IN, Arruda LCP, de Santana BB, de Moura TCM, Guerra MMP, Bezerra DG, Carneiro GF, Silva SV.The objective of this study was to evaluate the effects of the addition of different concentrations of ozone to quarter horse semen submitted to cryopreservation. Six ejaculates from four stallions were collected and were divided in four experimental groups: a control group (BotuCRIO® extender) and three other groups with BotuCRIO® ozonized at concentrations of 6, 8 and 12 μg of O/mL. The semen samples were diluted (200 x 10 spermatozoa/mL), filled in straws and frozen. After thawing (37 ºC, 30s), the samples were evaluated at 0, 30 and 60 minutes of incubation regarding sperm kinetics by ...
Nichols CL, Doherty TJ, Schumacher J, Jones PD, Sun X.To determine whether palmar digital nerve (PDN) blockade in horses with a combination of dexmedetomidine and mepivacaine would block the response to mechanical force applied to the digit longer than would anesthetizing these nerves with mepivacaine alone or dexmedetomidine alone. Methods: 8 mares with no signs of lameness. Methods: In a randomized, crossover, blinded, experimental study, both PDNs of the same forelimb of each horse were anesthetized by perineural injection with either 30 mg mepivacaine alone, 250 µg of dexmedetomidine alone, or 30 mg mepivacaine combined with 250 µg of dexme...
Fojtík L, Fiala J, Pompach P, Chmelík J, Matoušek V, Beier P, Kukačka Z, Novák P.Covalent labeling of proteins in combination with mass spectrometry has been established as a complementary technique to classical structural methods, such as X-ray, NMR, or cryogenic electron microscopy (Cryo-EM), used for protein structure determination. Although the current covalent labeling techniques enable the protein solvent accessible areas with sufficient spatial resolution to be monitored, there is still high demand for alternative, less complicated, and inexpensive approaches. Here, we introduce a new covalent labeling method based on fast fluoroalkylation of proteins (FFAP). FFAP u...
Carvalho JRG, Conde G, Antonioli ML, Santana CH, Littiere TO, Dias PP, Chinelatto MA, Canola PA, Zara FJ, Ferraz GC.In horses, there is an increasing interest in developing long-lasting drug formulations, with biopolymers as viable carrier alternatives in addition to their use as scaffolds, suture threads, screws, pins, and plates for orthopedic surgeries. This communication focuses on the prolonged biocompatibility and biodegradation of PLA, prepared by hot pressing at 180 °C. Six samples were implanted subcutaneously on the lateral surface of the neck of one horse. The polymers remained implanted for 24 to 57 weeks. Physical examination, plasma fibrinogen, and the mechanical nociceptive threshold (MNT) w...
Philip M, Karakka Kal AK, Subhahar MB, Karatt TK, Mathew B, Perwad Z.Performance-enhancing substances and methods have become a serious problem in competitive sports. The hypoxia-inducible factor (HIF) stabilizers can enhance the organism's capacity for molecular oxygen transport and are likely to be abused as performance-enhancing agents in sports. This paper describes the metabolic conversion of the popular hypoxia inducible factor-prolyl hydroxylase (HIF-PH) inhibitors, namely, daprodustat, desidustat, and vadadustat using equine liver microsomes, determined on a QExactive high-resolution mass spectrometer. During this study, a total of 10 metabolites for da...
Kuroda T, Minamijima Y, Nomura M, Yamashita S, Yamada M, Nagata S, Mita H, Tamura N, Fukuda K, Kuwano A, Kusano K, Toutain PL, Sato F.For medication control in several jurisdictions, withdrawal time is the period of refrain from racing after drug administration. It is set by adding a safety period to an experimental detection time. However, there are no reports of statistical analyses of detection time for the determination of withdrawal time in flunixin meglumine-treated horses. Objective: To analyse the population pharmacokinetics of flunixin in horses through the generation of a dataset for detection time statistical analysis and predictions via Monte Carlo simulation. Methods: Experimental study. Methods: Drug plasma and...
Amado-Fuentes M, Gozalo M, Garcia-Gomez A, Barrios-Fernandez S.People with disabilities due to genetic origin often present high levels of stress: non-pharmacological interventions such as Equine-Assisted Interventions (EAI) may be a useful strategy. The objective of this pilot study was to evaluate stress levels in two participants with 22q11.2 deletion syndrome diagnosis, immediately after carrying out the EAI. A single case experimental design methodology was chosen due to the small sample size. Two participants with 22q11.2 Deletion Syndrome, a rare disease, with different comorbidities were included. The present study considered the EAI as the indepe...
Lepage OM, Di Francesco P, Moulin N, Gangl M, Texier G, Marchi J, Cadoré JL.Background: The management of bleeding originating from the guttural pouch (GP) has a high success rate, but the resolution of the macroscopic inflammatory lesions in the case of mycosis (GPM) is highly variable; the resolution of neurological disorders is inconstant and challenging. Objectives: Our aim was to test the feasibility and safety of topical oxygen therapy (TOT) in horses after induction of GPM and in cases with naturally occurring disease. Study design: This study was an in vivo experimental and retrospective two-phase study. Methods: During phase 1, the pilot study, both GPs were ...
Werner LA, Hardy J, Bertone AL.To compare intra-articular (IA) and bone gentamicin concentrations achieved after intra-articular administration or regional intravenous perfusion (RIP). Methods: Experimental study. Methods: Twelve healthy adult horses. Methods: Horses were assigned to 2 treatment groups (n = 6/group): Group 1, 1 g gentamicin administered simultaneously in both left and right metacarpophalangeal joints and group 2, 1 g gentamicin administered simultaneously in both left and right lateral palmar veins. Serum, synovial fluid, and bone biopsy specimens were collected. Gentamicin concentrations were determined by...
Peterson RB, Goyal SM.A comparative study was carried out to determine the relative sensitivities of eight different cell culture systems to six different herpesviruses of animals. The cells used were: OFL (ovine fetal lung), ML (mink lung), FK (ferret kidney), PTK-2 (potoroo kidney), TEK (turkey embryo kidney), ED (equine dermal), BT (bovine turbinate), and PK15 (porcine kidney). The viruses tested were: PRV (pseudorabies) of swine, CPHV (caprine herpesvirus), IBRV (infectious bovine rhinotracheitis virus), DN-599 strain of bovine herpesvirus type 4, EHV-1 (equine herpesvirus), and CHV (canine herpesvirus). On the...
van de Water E, Oosterlinck M, Dumoulin M, Korthagen NM, van Weeren PR, van den Broek J, Everts H, Pille F, van Doorn DA.Nutraceuticals are often used in the management of equine osteoarthritis, but scientific evidence of their efficacy is lacking. Objective: To study the preventive effects of two new nutraceuticals after the experimental induction of synovitis in comparison with positive and negative control treatments. Methods: Blinded, controlled, randomised experiment. Methods: Twenty-four healthy Standardbred horses were randomly allocated to supplement AT (multi-ingredient, 28 days), supplement HP (collagen hydrolysate, 60 days), meloxicam (4 days) or placebo (60 days). Synovitis was induced in the right i...
Tangtrongsup S, Kisiday JD.Dexamethasone is known to support mesenchymal stem cell (MSC) chondrogenesis, although the effects of dose and timing of exposure are not well understood. The objective of this study was to investigate these variables using a laboratory model of MSC chondrogenesis. Methods: Equine MSCs were encapsulated in agarose and cultured in chondrogenic medium with 1 or 100 nM dexamethasone, or without dexamethasone, for 15 days. Samples were analyzed for extracellular matrix (ECM) accumulation, prostaglandin E2 and alkaline phosphatase secretion, and gene expression of selected collagens and catabolic e...
Sanchez-Teran AF, Bracamonte JL, Hendrick S, Burguess HJ, Duke-Novakovski T, Schott M, Hoff B, Rubio-Martínez LM.To evaluate the effect of arthroscopic lavage on systemic serum amyloid A (SAA) and SAA, total protein, nucleated cell count, and percentage of neutrophils in synovial fluid in healthy horses. Methods: Prospective experimental study. Methods: Healthy adult horses (n = 6). Methods: Middle carpal joints were randomly assigned to 1 of 2 treatments: arthrocentesis (controls) or arthroscopic lavage, with 30 day washout period between treatments. Synovial fluid and blood samples were collected at 0, 24, 48, 72, 96, and 120 hours. Measurements included systemic and synovial fluid SAA, as well as ...
Devireddy RV, Swanlund DJ, Olin T, Vincente W, Troedsson MH, Bischof JC, Roberts KP.Optimization of equine sperm cryopreservation protocols requires an understanding of the water permeability characteristics and volumetric shrinkage response during freezing. A cell-shape-independent differential scanning calorimeter (DSC) technique was used to measure the volumetric shrinkage during freezing of equine sperm suspensions at cooling rates of 5 degrees C/min and 20 degrees C/min in the presence and absence of cryoprotective agents (CPAs), i.e., in the Kenney extender and in the lactose-EDTA extender, respectively. The equine sperm was modeled as a cylinder of length 36.5 microm a...
Burger D, Thomas S, Aepli H, Dreyer M, Fabre G, Marti E, Sieme H, Robinson MR, Wedekind C.Genes of the major histocompatibility complex (MHC) have been shown to influence social signalling and mate preferences in many species, including humans. First observations suggest that MHC signalling may also affect female fertility. To test this hypothesis, we exposed 191 female horses () to either an MHC-similar or an MHC-dissimilar stimulus male around the time of ovulation and conception. A within-subject experimental design controlled for non-MHC-linked male characteristics, and instrumental insemination with semen of other males ( = 106) controlled for potential confounding effects of ...
Schubert S, Brehm W, Hillmann A, Burk J.For clinical applications of multipotent mesenchymal stromal cells (MSCs), serum-free culture is preferable to standardize cell products and prevent contamination with pathogens. In contrast to human MSCs, knowledge on serum-free culture of large animal MSCs is limited, despite its relevance for preclinical studies and development of veterinary cellular therapeutics. This study aimed to evaluate the suitability of a commercially available serum-free human MSC medium for culturing equine adipose-derived MSCs in comparison with human adipose MSCs. Enzyme-free isolation by explant technique and e...
Pusterla N, Chae JS, Kimsey RB, Berger Pusterla J, DeRock E, Dumler JS, Madigan JE.Most human granulocytic ehrlichiosis (HGE) studies carried out in horses use needle inoculation of infected leucocytes or cell cultures. This route of inoculation does not accurately reflect natural infection of the tick-borne agent. To investigate whether tick transmission influences the course of granulocytic ehrlichiosis in the horse model, experimental transmission through infected laboratory-reared Ixodes scapularis ticks was attempted into two healthy horses. One additional horse served as negative control and was exposed to uninfected ticks. Eleven days after exposure to nymphal or adul...
Divers TJ, Cummings JE, de Lahunta A, Hintz HF, Mohammed HO.To determine whether equine motor neuron disease (EMND) could be induced in adult horses fed a diet low in vitamin E and high in copper and iron. Methods: 59 healthy adult horses. Methods: Horses in the experimental group (n = 8) were confined to a dirt lot and fed a concentrate low in vitamin E and high in iron and copper in addition to free-choice grass hay that had been stored for 1 year. Control horses (n = 51) were fed a concentrate containing National Research Council-recommended amounts of copper, iron, and vitamin E. The hay fed to control horses was the same as that fed to experimenta...
Klohonatz KM, Nulton LC, Hess AM, Bouma GJ, Bruemmer JE.Maternal recognition of pregnancy (MRP) in the mare is an unknown process. In a non-pregnant mare on day 14 post-ovulation (PO), prostaglandin F2α (PGF) is secreted by the endometrium causing regression of the corpus luteum. Prior to day 14, MRP must occur in order to attenuate secretion of PGF. The embryo is mobile throughout the uterus due to uterine contractions from day of entry to day 14. It is unknown what signaling is occurring. Literature stated that infusing oil or placing a glass marble into the equine uterus prolongs luteal lifespan and that in non-pregnant mares, serum exosomes co...
Rochais C, Sébilleau M, Houdebine M, Bec P, Hausberger M, Henry S.Attention is described as the ability to process selectively one aspect of the environment over others. In this study, we characterized horses' spontaneous attention by designing a novel visual attention test (VAT) that is easy to apply in the animal's home environment. The test was repeated over three consecutive days and repeated again 6 months later in order to assess inter-individual variations and intra-individual stability. Different patterns of attention have been revealed: 'overall' attention when the horse merely gazed at the stimulus and 'fixed' attention characterized by fixity and...
Tharasanit T, Colleoni S, Galli C, Colenbrander B, Stout TA.Vitrifying oocytes is a potentially valuable means of preserving the female germ line, but significantly compromises oocyte developmental competence. This study examined the hypothesis that the cumulus complex protects the oocyte during vitrification. Vitrified-warmed immature cumulus oocyte complexes (COCs) were labelled with a plasma membrane impermeant DNA marker (ethidium homodimer-1) to examine the percentage and location of dead cumulus cells, and to investigate the effect of the proportion of dead cells (+1,+2 or +3) on the success of in vitro maturation (IVM). Further, oocytes were lab...
Yang X, Chasteen ND.Electron paramagnetic resonance spectroscopy and gel permeation chromatography were employed to study the molecular diffusion of a number of small nitroxide spin probes (approximately 7-9 A diameter) into the central cavity of the iron-storage protein ferritin. Charge and polarity of these radicals play a critical role in the diffusion process. The negatively charged radical 4-carboxy-2,2,6,6-tetramethylpiperidine-N-oxyl (4-carboxy-TEMPO) does not penetrate the cavity whereas the positively charged 4-amino-TEMPO and 3-(aminomethyl)-proxyl radical and polar 4-hydroxy-TEMPO radical do. Unlike th...
Smith KC, Whitwell KE, Mumford JA, Gower SM, Hannant D, Tearle JP.Twelve Welsh Mountain pony mares in late gestation were infected intranasally with EHV-1 (AB4 isolate) at dose rates from 10(3) to 10(7.3) TCID50. This resulted in 3 cases of paresis, at Days 9, 10 and 12 after inoculation, and 5 abortions, at Days 6, 9, 18, 19 and 20. Euthanasia was performed between Days 6 and 21, with collection of uterine specimens for histopathology, virus isolation and immunoperoxidase staining from the pregnant horn, non-pregnant horn and body. EHV-1 replication in endometrial vessels was detected as early as Day 6 and was maximal at Days 9-11, when widespread thrombois...
Jackson TA, Osburn BI, Cordy DR, Kendrick JW.Experimental infection with equine herpesvirus 1 (rhinopneumonitis) resulted in neurologic disease in 8 of 15 inoculated horses. Nonpregnant animals did not develop clinical disease, and microscopic examination of tissues revealed no changes. In all mares between 3 and 9 months of gestation, a neurologic syndrome appeared 6 to 8 days after inoculation. Mares inoculated when 10 months pregnant did not develop neurologic disorders, but several aborted. The histopathologic change common to both sequelae was vasculitis, involving smaller arteries and veins. Although blood vessel changes were detec...
Yan W, Faisal SM, Divers T, McDonough SP, Akey B, Chang YF.Little information is available about experimental induction of leptospirosis in horses. Objective: Determine serologic, hematologic responses of horses to Leptospira interrogans serovar Kennewicki infection. Methods: Four adult horses seronegative for leptospirosis. Methods: Experimental and observational study. Horses were challenged with an equine isolate of L. interrogans serovar Kennewicki at 2 different doses and different inoculation sites. After challenge, the horses were monitored for 60 days. Blood, urine, and aqueous humor samples were collected at intervals until euthanasia 60 days...
Kim HY, Mott J, Zhi N, Tajima T, Rikihisa Y.Human granulocytic ehrlichiosis (HGE), a tick-borne zoonosis, is caused by an obligatory intragranulocytic bacterium, the HGE agent, a strain of Anaplasma phagocytophila. The equine model of HGE is considered valuable in understanding pathogenic and immune mechanisms of HGE. In the present study, cytokine mRNA expression by peripheral blood leukocytes (PBLs) in horses was examined during the course of infection by intravenous inoculation of A. phagocytophila or by allowing feeding by infected ticks. The p44 genes encoding the major outer membrane protein P44s of A. phagocytophila were detected...
Aksular M, Calvo-Pinilla E, Marín-López A, Ortego J, Chambers AC, King LA, Castillo-Olivares J.African horse sickness is a severe, often fatal, arboviral disease of equids. The control of African horse sickness virus (AHSV) in endemic countries is based currently on the use of live attenuated vaccines despite some biosafety concerns derived from its biological properties. Thus, experimental vaccination platforms have been developed over the years in order to avoid the biosafety concerns associated with the use of attenuated vaccines. Various studies showed that baculovirus-expressed AHSV-VP2 or modified Vaccinia Ankara virus expressing AHSV-VP2 (MVA-VP2) induced virus neutralising antib...
Clarke EJ, Johnson E, Caamaño Gutierrez E, Andersen C, Berg LC, Jenkins RE, Lindegaard C, Uvebrant K, Lundgren-Åkerlund E, Turlo A, James V....Equine osteoarthritis (OA) is a heterogeneous, degenerative disease of the musculoskeletal system with multifactorial causation, characterized by a joint metabolic imbalance. Extracellular vesicles are nanoparticles involved in intracellular communication. Mesenchymal stem cell (MSC) therapy is a form of regenerative medicine that utilizes their properties to repair damaged tissues. Despite its wide use in veterinary practice, the exact mechanism of action of MSCs is not fully understood. The aim of this study was to determine the synovial fluid extracellular vesicle protein cargo following in...
Lindegaard C, Gleerup KB, Thomsen MH, Martinussen T, Jacobsen S, Andersen PH.To compare the effects of intra-articular (IA) versus IV administration of morphine on local and systemic inflammatory responses in horses with experimentally induced acute synovitis. Methods: 8 horses. Methods: Each horse received the following 2 treatments 4 hours after synovitis was induced: IA administration of morphine (0.05 mg/kg) with IV administration of 1 mL of saline (0.9% NaCl) solution/100 kg, and IA administration of 1 mL of saline solution/100 kg with IV administration of morphine (0.05 mg/kg). Treatments were administered in randomized order with a washout period of 3 weeks betw...
González Vázquez AG, Blokpoel Ferreras LA, Bennett KE, Casey SM, Brama PA, O'Brien FJ.Joint repair remains a major challenge in orthopaedics. Recent progress in biomaterial design has led to the fabrication of a plethora of promising devices. Pre-clinical testing of any joint repair strategy typically requires the use of large animal models (e.g., sheep, goat, pig or horse). Despite the key role of such models in clinical translation, there is still a lack of consensus regarding optimal experimental design, making it difficult to draw conclusions on their efficacy. In this context, the authors performed a systematic literature review and a risk of bias assessment on large anima...
Nyindo MB, Ristic M, Lewis GE, Huxsoll DL, Stephenson EH.Four ponies experimentally infected with Ehrlichia equi developed substantial cell-mediated immune responses, as measured by the leukocyte migration-inhibition test. Serum anti-E equi antibodies up to 1:1,280 were demonstrated by the indirect fluorescent antibody test. Cell-mediated immune responses returned to a base-line value by day 200 after primary inoculation, but serum antibody titers persisted for at least 300 days after inoculation. Two additional susceptible ponies, which were inoculated with convalescent blood or organ homogenates from ponies recovered from acute equine ehrlichiosis...
Stewart AA, Barrett JG, Byron CR, Yates AC, Durgam SS, Evans RB, Stewart MC.To compare viability and biosynthetic capacities of cells isolated from equine tendon, muscle, and bone marrow grown on autogenous tendon matrix. Methods: Cells from 4 young adult horses. Methods: Cells were isolated, expanded, and cultured on autogenous cell-free tendon matrix for 7 days. Samples were analyzed for cell viability, proteoglycan synthesis, collagen synthesis, and mRNA expression of collagen type I, collagen type III, and cartilage oligomeric matrix protein (COMP). Results: Tendon- and muscle-derived cells required less time to reach confluence (approx 2 weeks) than did bone marr...
Hussey GS, Goehring LS, Lunn DP, Hussey SB, Huang T, Osterrieder N, Powell C, Hand J, Holz C, Slater J.Equine herpesvirus myeloencephalitis (EHM) remains one of the most devastating manifestations of equine herpesvirus type 1 (EHV-1) infection but our understanding of its pathogenesis remains rudimentary, partly because of a lack of adequate experimental models. EHV-1 infection of the ocular vasculature may offer an alternative model as EHV-1-induced chorioretinopathy appears to occur in a significant number of horses, and the pathogenesis of EHM and ocular EHV-1 may be similar. To investigate the potential of ocular EHV-1 as a model for EHM, and to determine the frequency of ocular EHV-1, our ...
Malik CL, Stover SM, Martin RB, Gibeling JC.Previous studies of the fracture properties of cortical bone have suggested that the fracture toughness increases with crack length, which is indicative of rising R-curve behavior. Based on this indirect evidence and the similarity of bone to ceramic matrix composites, we hypothesized that bone would exhibit rising R-curve behavior in the transverse orientation and that the characteristics of the R-curves would be regionally dependent within the cortex due to variations in bone microstructure and toughening mechanisms. To test these hypotheses, we conducted R-curve experiments on specimens fro...
Petter-Puchner AH, Froetscher W, Krametter-Froetscher R, Lorinson D, Redl H, van Griensven M.While fibrin sealant (FS) and equine collagen (EC) have been used as scaffold materials in experimental spinal cord injury (SCI), questions concerning neurocompatibility still remain. In this study, we assessed potential adverse effects, as well as functional and histological impact of FS and EC in subtotal hemisection of the thoracic spinal cord (SC) in rats. Methods: 124 male rats were randomly assigned to four main groups (n=31): Sham (SH), Lesion only (L), fibrin sealant (GFS) and equine collagen group (GEC). SH animals received laminectomy only; all other animals underwent subtotal latera...
de Laat MA, van Eps AW, McGowan CM, Sillence MN, Pollitt CC.Laminitis has many triggers and comparing the histopathology of lesions induced by different causes may help to establish whether a common mechanism or multiple pathologies are involved. The aim of this study was to describe the microscopical lesions and to quantify morphometric changes in the lamellae of horses with insulin-induced (n=4) and oligofructose (OF)-induced laminitis (n=4) compared with normal controls (n=4). Archived lamellar samples collected during two previous studies were used. Laminitis was induced within 48 h in standardbred horses with either a euglycaemic, hyperinsulinaemi...
Daly JM, Yates RJ, Browse G, Swann Z, Newton JR, Jessett D, Davis-Poynter N, Mumford JA.Vaccination and challenge studies in ponies are the most relevant experimental system for predicting whether strains included in equine influenza vaccines are relevant, but they are difficult to perform. Objective: In order to investigate the feasibility of using a small animal model, results of a cross-protection study in hamsters were compared with those from a previous pony challenge experiment. Methods: Animals were immunised with inactivated vaccines containing one of 4 strains of equine influenza A H3N8 subtype virus isolated over a 26 year period (1963 to 1989), then challenged with a 1...
Pusterla N, Pusterla JB, Braun U, Lutz H.Four cows and four horses were infected experimentally with Ehrlichia phagocytophila, the cause of tickborne fever in ruminants, and with human granulocytic ehrlichia-like agent, a recently discovered species that infects people, horses and dogs in the USA and Europe. They were infected in either order, 30 days apart, to investigate serological cross-reactivity within the Ephagocytophila genogroup. The course of infection was assessed by routine clinical, haematological, serological and polymerase chain reaction (PCR) examinations. Two of the cows infected with Ephagocytophila and two of the h...
