In vitro research involving horses refers to the study of equine cells, tissues, or biological molecules outside their normal biological context, typically in controlled laboratory environments. This research approach allows scientists to investigate cellular processes, molecular interactions, and the effects of various treatments without the ethical and logistical complexities of in vivo studies. In vitro studies contribute to understanding equine physiology, pathology, and pharmacology by providing insights into cellular responses to pathogens, drugs, and other stimuli. This page compiles peer-reviewed research studies and scholarly articles that explore various in vitro methodologies and their applications in equine science, including cell culture techniques, molecular assays, and drug efficacy testing.
Braune S, Walter M, Schulze F, Lendlein A, Jung F.For in vitro studies assessing the interaction of platelets with implant materials, common and standardized protocols for the preparation of platelet rich plasma (PRP) are lacking, which may lead to non-matching results due to the diversity of applied protocols. Particularly, the aging of platelets during prolonged preparation and storage times is discussed to lead to an underestimation of the material thrombogenicity. Here, we study the influence of whole blood- and PRP-storage times on changes in platelet morphology and function. Blood from apparently healthy subjects was collected according...
Dietze K, Slosarek I, Fuhrmann-Selter T, Hopperdietzel C, Plendl J, Kaessmeyer S.Arterial or venous thromboses are frequent clinical complications with the risk of fatal progression. Recent studies suggest the disruption of angiogenesis in the course of thrombus resolution as the underlying pathomechanism. Very similar to the situation in human patients, equine vessels have been described to be particularly susceptible to thrombosis. In contrast to humans, equine donors are readily available to obtain organs and tissues for isolation of endothelial cells. Objective of this study was to isolate equine endothelial cells and develop an angiogenesis assay from primary cultures...
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...
Guimarães T, Lopes G, Pinto M, Silva E, Miranda C, Correia MJ, Damásio L, Thompson G, Rocha A.Freezability of equine semen may be influenced by microorganism population of semen. The objective of this study was to verify the effect of single-layer density gradient centrifugation (SLC) of fresh semen before cryopreservation on semen's microbial load (ML) and sperm cells kinetics after freezing-thawing. For that, one ejaculate was collected from 20 healthy stallions and split into control (C) samples (cryopreserved without previous SLC) and SLC samples (subjected to SLC). Semen cryopreservation was performed according to the same protocol in both groups. Microbial load of each microorgan...
Walter KM, Moore CE, Bozorgmanesh R, Magdesian KG, Woods LW, Puschner B.Two horses were referred for methemoglobinemia and hemolytic anemia following 5 acute deaths in their herd from an unidentified toxin source. Horses have a greater risk than other mammalian species of developing methemoglobinemia and hemolytic anemia following ingestion of oxidizing toxins, due to deficiencies in the mechanisms that protect against oxidative damage in erythrocytes. Their susceptibility to oxidative erythrocyte damage is evident in the numerous cases of red maple (Acer rubrum) toxicosis. The suspected toxins causing A. rubrum toxicosis are tannic acid, gallic acid, and a metabo...
Burk SV, Dangoudoubiyam S, Brewster-Barnes T, Bryant UK, Howe DK, Carter CN, Vanzant ES, Harmon RJ, Kazacos KR, Rossano MG.Currently, diagnosis of Parascaris equorum infection in equids is limited to patent infections. The goals of this study were to culture P. equorum larvae in vitro and identify excretory-secretory (ES) products for prepatent diagnostic testing. Parascaris equorum L2/L3 larvae were hatched and cultured for up to 3 weeks for ES product collection. Fifth stage (L5) P. equorum were also cultured for ES product collection. Examination of ES fractions by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and silver stain revealed L2/L3 products ranging from 12-94 kDa and L5 products...
Lopez MJ, Jarazo J.According to Greek mythology, Prometheus' liver grew back nightly after it was removed each day by an eagle as punishment for giving mankind fire. Hence, contrary to popular belief, the concept of tissue and organ regeneration is not new. In the early 20th century, cell culture and ex vivo organ preservation studies by Alexis Carrel, some with famed aviator Charles Lindbergh, established a foundation for much of modern regenerative medicine. While early beliefs and discoveries foreshadowed significant accomplishments in regenerative medicine, advances in knowledge within numerous scientific di...
Rash A, Woodward A, Bryant N, McCauley J, Elton D.H3N8 equine influenza virus (EIV) has caused disease outbreaks in horses across the world since its first isolation in 1963. However, unlike human, swine and avian influenza, there is relatively little sequence data available for this virus. The majority of published sequences are for the segment encoding haemagglutinin (HA), one of the two surface glycoproteins, making it difficult to study the evolution of the other gene segments and determine the level of reassortment occurring between sub-lineages. Methods: To facilitate the generation of full genome sequences for EIV, we developed a simpl...
Brehm W, Burk J, Delling U.Stem cells in the form of mesenchymal stromal cells derived from various sources have been identified to have the potential of supporting the therapy of joint disease in the horse, and preliminary data has been published about the clinical application of stem cells in horses suffering from clinical joint disease. Furthermore, the horse is recognized to be the ideal large animal model for the preclinical study of cell therapy in joints. The advantage of this species in this respect is the size of the joints, which makes surgical applications practically feasible in analogy to human surgery. Add...
Löfgren M, Ekman S, Svala E, Lindahl A, Ley C, Skiöldebrand E.Formation of synovial joints includes phenotypic changes of the chondrocytes and the organisation of their extracellular matrix is regulated by different factors and signalling pathways. Increased knowledge of the normal processes involved in joint development may be used to identify similar regulatory mechanisms during pathological conditions in the joint. Samples of the distal radius were collected from prenatal and postnatal equine growth plates, zones of Ranvier and articular cartilage with the aim of identifying Notch signalling components and cells with stem cell-like characteristics and...
Coutinho da Silva MA, Seidel GE, Squires EL, Graham JK, Carnevale EM.Objectives were to determine the effects of extracellular Ca(2+) and milk proteins on intracellular Ca(2+) concentrations in stallion sperm; and to determine the effects of single caseins on sperm binding to the zona pellucida (ZP). In Experiment I, sperm were incubated in media containing 2 or 4mM Ca(2+) and intracellular Ca(2+) concentration was determined after ionomycin treatment and long-term incubation (3h). Extracellular Ca(2+) concentrations (2 compared with 4mM) did not affect baseline intracellular Ca(2+) concentration of sperm. However, incubating sperm in a medium containing 4 comp...
Brazil TJ, Dixon PM, Haslett C, Murray J, McGorum BC.The aim of this study was to characterise constitutive apoptosis in equine peripheral blood neutrophils, including assessment of factors that potentially modulate neutrophil survival through alteration of the rate of constitutive apoptosis. Cells underwent spontaneous time-dependent constitutive apoptosis when aged in culture for up to 36 h, developing the structural and functional features of apoptosis observed in many cell types, including human neutrophils. Neutrophils undergoing apoptosis also had diminished zymosan activated serum (ZAS)-stimulated chemiluminescence, but maintained respo...
Esteves CL, Sharma R, Dawson L, Taylor SE, Pearson G, Keen JA, McDonald K, Aurich C, Donadeu FX.Expression of several putative markers of pluripotency (OCT4, SOX2, NANOG, LIN28A, REX1, DNMT3B and TERT) was examined in a range of equine tissues, including early embryos, induced pluripotent stem cells (iPSCs), testis, adipose- and bone marrow-derived mesenchymal stromal cells (MSCs), and keratinocytes. Transcript levels of all markers were highest in embryos and iPSCs and, except for SOX2, were very low or undetectable in keratinocytes. Mean expression levels of all markers were lower in testis than in embryos or iPSCs and, except for DNMT3B, were higher in testis than in MSCs. Expression ...
Equine germplasm bank management involves not only the conservation and use of semen doses, in addition it can also be a resource to study stallion semen quality and after thawing semen properties for reproductive purposes. A possible criterion to measure quality may be based on differential gene expression of loci involved during spermatogenesis and sperm quality maturation. The rapid degradation of sperm after thawing affects the integrity and availability of RNA. In this study we have analyzed genes expressed in equine cryopreserved sperm, which provided an adequate amplification, specifici...
Mosseri S, Hetzel U, Hahn S, Michaloupoulou E, Sallabank HC, Knottenbelt DC, Kipar A.Sarcoids are the most prevalent equine skin tumours and remain a therapeutic challenge due to their differing clinical morphology, local aggressive behaviour, and high recurrence following surgical treatment. In vitro, sarcoid derived fibroblasts are invasive and express matrix metalloproteinase (MMP) -1, -2 and -9. It was hypothesised that the MMPs produced by neoplastic cells play a role in both their local invasiveness and interaction with the overlying epidermis (picket fence formation). The objective of this morphological study was to investigate the local behaviour and in situ MMP expres...
Nedjadi T, Moran AW, Al-Rammahi MA, Shirazi-Beechey SP.The diet of the horse, pasture forage (grass), is fermented by the equine colonic microbiota to short-chain fatty acids, notably acetate, propionate and butyrate. Short-chain fatty acids provide a major source of energy for the horse and contribute to many vital physiological processes. We aimed to determine both the mechanism of butyrate uptake across the luminal membrane of equine colon and the nature of the protein involved. To this end, we isolated equine colonic luminal membrane vesicles. The abundance and activity of cysteine-sensitive alkaline phosphatase and villin, intestinal luminal ...
Rebordão MR, Carneiro C, Alexandre-Pires G, Brito P, Pereira C, Nunes T, Galvão A, Leitão A, Vilela C, Ferreira-Dias G.Besides the classical functions, neutrophils (PMNs) are able to release DNA in response to infectious stimuli, forming neutrophil extracellular traps (NETs) and killing pathogens. The pathogenesis of endometritis in the mare is not completely understood. The aim was to evaluate the in vitro capacity of equine PMNs to secrete NETs by chemical activation, or stimulated with Streptococcus equi subspecies zooepidemicus (Szoo), Escherichia coli (Ecoli) or Staphylococcus capitis (Scap) strains obtained from mares with endometritis. Ex vivo endometrial mucus from mares with bacterial endometritis wer...
Tew SR, McDermott BT, Fentem RB, Peffers MJ, Clegg PD.Messenger RNA (mRNA) decay rates control not only gene expression levels, but also responsiveness to altered transcriptional input. We undertook this study to examine transcriptome-wide posttranscriptional regulation in both normal and osteoarthritic (OA) human articular chondrocytes. Methods: Human articular chondrocytes were isolated from normal or OA tissue. Equine articular chondrocytes were isolated from young or old horses at a commercial abattoir. RNA decay was measured across the transcriptome in human cells by microarray analysis following an actinomycin D chase. Messenger RNA levels ...
Pascucci L, Alessandri G, Dall'Aglio C, Mercati F, Coliolo P, Bazzucchi C, Dante S, Petrini S, Curina G, Ceccarelli P.Multipotent mesenchymal stromal cells (MSCs) have attracted a great deal of interest, due to several distinctive features, including the ability to migrate to damaged tissue and to participate in tissue regeneration. There is increasing evidence that membrane vesicles (MVs), comprising exosomes and shedding vesicles, represent a key component, responsible for many of the paracrine effects of MSCs. The aim of the present study was to establish whether equine adipose-derived MSCs (E-AdMSCs) produce MVs that are capable of influencing angiogenesis, a key step in tissue regeneration. A morphologic...
Boeer U, Buettner FF, Klingenberg M, Antonopoulos GC, Meyer H, Haverich A, Wilhelmi M.The limited biocompatibility of decellularized scaffolds is an ongoing challenge in tissue engineering. Here, we demonstrate the residual immunogenicity of an extensively decellularized equine carotid artery (dEAC(intens)) and identify the involved immunogenic components. EAC were submitted to an elaborated intensified decellularization protocol with SDS/sodium desoxycholate for 72 h using increased processing volumes (dEAC(intens)), and compared to dEAC(ord) prepared by an ordinary protocol (40 h, normal volumes). Matrix integrity was checked via correlative volumetric visualization which rev...
Fernandez-Fuente M, Terracciano CM, Martin-Duque P, Brown SC, Vassaux G, Piercy RJ.Dysfunctional skeletal muscle calcium homeostasis plays a central role in the pathophysiology of several human and animal skeletal muscle disorders, in particular, genetic disorders associated with ryanodine receptor 1 (RYR1) mutations, such as malignant hyperthermia, central core disease, multiminicore disease and certain centronuclear myopathies. In addition, aberrant skeletal muscle calcium handling is believed to play a pivotal role in the highly prevalent disorder of Thoroughbred racehorses, known as Recurrent Exertional Rhabdomyolysis. Traditionally, such defects were studied in human an...
Morrell JM, Johannisson A.The effect on sperm motility and chromatin integrity of adding homologous or heterologous equine seminal plasma (SP) to fresh stallion spermatozoa selected by single layer centrifugation (SLC) was studied. No statistical difference in mean progressive motility was seen after adding SP at time 0 h, although there were differences for individual stallions. The proportion of spermatozoa with high velocity was increased compared to untreated SLC-selected spermatozoa (P < 0.05), with significant differences between individuals (P < 0.01). When the SLC samples were stored for 24 h before a...
Varner DD, Gibb Z, Aitken RJ.Stallion fertility is a vast subject, with a wide array of permutations that can impact reproductive performance in either positive or negative ways. This review is intended to address a mere segment of the male fertility issue, but the very essence of the male contribution to fertilisation, that of the spermatozoon. Spermatozoal ultrastructure and form-to-function are detailed and spermatozoal metabolism is discussed, with specific reference to distinctive characteristics of stallion spermatozoa. Lastly, methods for assessment of spermatozoal function are considered, with emphasis on spermato...
Donnelly KS, Giuliano EA, Sharm A, Mohan RR.To explore the effect of suberoylanilide hydroxamic acid (SAHA) (i) on corneal fibroblast differentiation, morphology, and viability; and (ii) on the expression levels of matrix metalloproteinases (MMPs) 2 and 9 using an in vitro model of equine corneal fibrosis. Methods: Healthy donor corneas were used to generate primary cultures of equine corneal fibroblasts. The fibroblasts were exposed to 5 ng/mL TGFβ1 to induce myofibroblast formation. The cultures were treated with either 5 μm or 10 μm SAHA for 72 h in the presence of TGFβ1. Real-time PCR and immunocytochemistry were used to determi...
Garvican ER, Cree S, Bull L, Smith RK, Dudhia J.Autologous mesenchymal stem cell (MSC) injection into naturally-occurring equine tendon injuries has been shown to be safe and efficacious and protocols inform translation of the technique into humans. Efficient transfer of cells from the laboratory into tissue requires well-validated transport and implantation techniques. Methods: Cell viability in a range of media was determined over 72 hours and after injection through a 19G, 21G or 23G needle. Viability, proliferation and apoptosis were analysed using TrypanBlue, alamarBlue® and AnnexinV assays. Results: Cell viability was similar in all...
Laverty G, McCloskey AP, Gilmore BF, Jones DS, Zhou J, Xu B.Self-assembling dipeptides conjugated to naphthalene show considerable promise as nanomaterial structures, biomaterials, and drug delivery devices. Biomaterial infections are responsible for high rates of patient mortality and morbidity. The presence of biofilm bacteria, which thrive on implant surfaces, are a huge burden on healthcare budgets, as they are highly resistant to current therapeutic strategies. Ultrashort cationic self-assembled peptides represent a highly innovative and cost-effective strategy to form antibacterial nanomaterials. Lysine conjugated variants display the greatest po...
Wong A, Ghassemi E, Yellowley CE.The intermediate filament protein nestin is used as a marker for neural stem cells, and its expression is inversely correlated with cellular differentiation. More recently, nestin expression has also been described in other cell types including multipotential mesenchymal stromal cells (MSCs). In this study, we examined the expression of nestin in equine, canine and human bone marrow-derived MSCs undergoing osteogenic differentiation, to determine whether nestin levels were attenuated as the cells acquired a more mature phenotype. In addition, the expression of nestin may be under the influence...
Murata D, Miyakoshi D, Hatazoe T, Miura N, Tokunaga S, Fujiki M, Nakayama K, Misumi K.Cartilage regeneration with cell therapy following arthroscopic surgery could be used in racehorses with intra-articular fractures (IAF) and osteochondritis dissecans (OCD). The aims of this study were to investigate the origin and multipotency of stromal cells in the synovial fluid (SF) of horses with intra-articular injury and synovitis, and to provide a new strategy for regeneration of lost articular cartilage. Mesenchymal stromal cells were isolated from SF of horses with IAF and OCD. Multipotency was analysed by RT-PCR for specific mRNAs and staining for production of specific extracellul...
López C, Carmona JU, Giraldo CE, Alvarez ME.1) To evaluate the bacteriostatic in vitro effect of pure platelet-rich plasma (P-PRP), pure platelet-rich gel (P-PRG), leukocyte-poor gel (LPG), platelet-poor plasma (PPP), and heat inactivated plasma (IP) against methicillin-sensitive Staphylococcus aureus (MSSA) over a period of 24 hours. 2) To determine the degradation of platelet factor-4 (PF-4), transforming growth factor beta 1 (TGF-β1), and platelet-derived growth factor isoform BB (PDGF-BB) in these equine blood components. 3) To establish correlations between platelet and leukocyte counts, PF-4 concentrations, and MSSA growth. Metho...
Campos-Chillòn LF, Suh TK, Barcelo-Fimbres M, Seidel GE, Carnevale EM.The objectives of this study were to: (1) determine an optimal method and stage of development for vitrification of bovine zygotes or early embryos; and (2) use the optimal procedure for bovine embryos to establish equine pregnancies after vitrification and warming of early embryos. Initially, bovine embryos produced by in-vitro fertilization (IVF) were frozen and vitrified in 0.25mL straws with minimal success. A subsequent experiment was done using two vitrification methods and super open pulled straws (OPS) with 1- or 8-cell bovine embryos. In Method 1 (EG-O), embryos were exposed to 1.5M e...
Lo CC, Thompson JA, Lowry VK, Varner DD.We used the sperm chromatin structure assay (SCSA) to study the change in stallion sperm DNA susceptibility to denaturation after exposure of extended semen to three different storage temperatures (5, 20, or 37 degrees C) at 7, 20, 31, and 46 h. In addition, we compared the rates of sperm DNA denaturation in fertile and subfertile stallions. Among fertile stallions, spermatozoa stored at 20 and 37 degrees C showed a significant (P 0.05) changes in the SCSA values measured over time, indicating maintenance of chromatin quality for up to 46 h. The COMP(alpha(t)) from stallions classified as sub...
Goszczynski DE, Tinetti PS, Choi YH, Hinrichs K, Ross PJ.Embryonic genome activation is a critical event in embryo development, in which the transcriptional program of the embryo is initiated. The timing and regulation of this process are species-specific. In vitro embryo production is becoming an important clinical and research tool in the horse; however, very little is known about genome activation in this species. The objective of this work was to identify the timing of genome activation, and the transcriptional networks involved, in in vitro-produced horse embryos. RNA-Seq was performed on oocytes and embryos at eight stages of development (MII,...
Clark P, Mogg TD, Tvedten HW, Korcal D.Delayed analysis of blood samples may be caused by restricted access to laboratories. Artifactual changes may occur in the measured analytes as a consequence of delayed analysis and may complicate interpretation of the data. Objective: The purpose of this study was to characterize artifactual changes in equine blood, due to storage, using the Advia 120 hematology analyzer. Methods: Samples of blood from 5 horses were analyzed using the Advia 120 soon after collection and again after 24 and 48 hours of storage at either 4 degrees C or ambient laboratory temperature ( approximately 24 degrees C)...
Ball BA, Vo A.The lipophilic fluorescent probe, 4,4-difluoro-5-(4-phenyl-1 ,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C11-BODIPY581/591) was used to evaluate changes in lipid peroxidation in equine spermatozoa during both short-term exposure to ferrous sulfate and sodium ascorbate in the presence of cumene hydroperoxide as well as during storage of spermatozoa at 5 degrees C for 48 hours. Peroxidation of C11-BODIPY581/591 was accompanied by a shift in fluorescence from red to green, and the relative amount of nonoxidized probe was determined as the ratio of red:(red + green) fluorescenc...
Sime A, McKellar Q, Nolan A.A serum-free cell culture method was developed for equine tracheal epithelial cells which allowed the growth and characterisation of the phenotypical properties of this cell type. Several variables influenced the efficacy of the attachment and growth of the isolated cells. Serum and a collagen matrix were essential components for efficient cell attachment. Once attachment had occurred, cell growth was enhanced by a serum-free medium containing bovine pituitary extract, retinoic acid, insulin, hydrocortisone, transferrin, epidermal growth factor, adrenaline and triiodothyronine. The mean time t...
Ramírez-Agámez L, Hernández-Avilés C, Ortíz I, Love CC, Varner DD, Hinrichs K.Equine spermatozoa appear to differ from spermatozoa of other species in using oxidative phosphorylation preferentially over glycolysis. However, there is little information regarding effects of different energy sources on measured parameters in equine spermatozoa. Objective: To determine the effect of three individual energy substrates, glucose, pyruvate, and lactate, on motion characteristics, membrane integrity, and acrosomal status of stallion spermatozoa. Methods: Freshly ejaculated stallion spermatozoa were incubated with combinations of glucose (5 mm), pyruvate (10 mm), and lactate (1...
Casey PJ, Hillman RB, Robertson KR, Yudin AI, Liu IK, Drobnis EZ.An acrosomal staining technique that can differentiate between living and dead sperm was developed for equine sperm. The fluoresceinated lectin Pisum sativum agglutinin (FITC-PSA) was used to identify the presence or absence of acrosomal contents, while the supravital nuclear dye Hoechst 33258 (H258) was used to assess viability. The accuracy of the FITC-PSA acrosomal stain was tested by comparing the percentage of sperm that had lost their acrosomal contents, detected by the staining method, with that detected by transmission electron microscopy (TEM). Following capacitation in vitro, the acr...
Altamura G, Corteggio A, Nasir L, Yuan ZQ, Roperto F, Borzacchiello G.Equine sarcoids are skin tumours of fibroblastic origin affecting equids worldwide. Bovine papillomavirus type-1 (BPV-1) and, less commonly, type-2 are recognized as etiological factors of sarcoids. The transforming activity of BPV is related to the functions of its major oncoprotein E5 which binds to the platelet-derived growth factor β receptor (PDGFβR) causing its phosphorylation and activation. In this study, we demonstrate, by coimmunoprecipitation and immunoblotting, that in equine sarcoid derived cell lines PDGFβR is phosphorylated and binds downstream molecules related to Ras-mitoge...
Love CC.Sperm quality assays have increased in number in the last 10 years. Most of these assays are flow cytometry based in application and are modified from assays that have been developed to measure somatic cell function. The goal of any sperm quality assay should be to advance the clinicians/researchers understanding of sperm cell function and the relationship to fertility. While these assays appear to measure somatic cell-like functions in sperm there tends to be little understanding how the results of these assays relate to fertility.
Freeman DA, Woods GL, Vanderwall DK, Weber JA.The hypothesis that equine embryos initiate oviductal transport in mares was tested by placing day 6 uterine embryos in the oviducts of day 2 (n = 10) or day 5 (n = 10) recipient mares and attempting to collect the embryos from the uterus 48 h later. To determine whether the surgical transfer procedure initiated oviductal transport, medium alone was placed in the oviducts of day 2 (n = 10) inseminated mares (sham transfer), and uterine embryo collections were attempted 48 h later. Embryos were transported through the oviduct of day 2 recipients by day 4 (instead of day 5 to 6) in six of ten ma...
Koepf EK, Burtnick LD.Horse plasma gelsolin labelled with benzophenone-4-isothiocyanate can be photochemically cross-linked to rabbit cardiac tropomyosin. The cross-linking proceeds with greater efficiency in calcium-containing buffers. Further evidence for interaction between these proteins is provided by retention of fluorescently labelled gelsolin on tropomyosin-agarose affinity columns and by the ability of tropomyosin to cause an increase in the fluorescence intensity of gelsolin labelled with fluorescein-5-isothiocyanate. Both of these effects require the presence of calcium ions.
Hartwig FP, Lisboa FP, Hartwig FP, Monteiro GA, Maziero RR, Freitas-Dell'Aqua CP, Alvarenga MA, Papa FO, Dell'Aqua JA.During the cooling process, sperm may suffer irreversible damage that compromises the fertility rate. Incorporating cholesterol-loaded cyclodextrin (CLC) represents a strategy to increase sperm resistance at low temperatures; however, high levels of cholesterol in the cell membrane can interfere with sperm capacitation. The goals of this study were to determine the CLC concentration and cooling temperature that produce optimal kinetic parameters and viability of sperm from stallions identified as bad coolers (BCs) and good coolers (GCs), as well as the effect of adding CLC on the occurrence of...
Clegg PD, Carter SD.A study was performed to identify the activation status of the gelatinase MMPs, MMP-2 and -9, in both normal and diseased equine articular tissues. In addition, the production and activation status of equine MMP-2 and -9 by equine articular cells and tissues in response to increasing IL-1beta concentrations was assessed. The study was performed to test the hypothesis that activation of MMPs is a fundamental step in the pathogenesis of joint diseases; and that this activation is mediated by the cytokine IL-1. Using purified equine MMP-2 and -9, the molecular weights of the zymogen and activated...
Womble A, Giguère S, Murthy YV, Cox C, Obare E.The objectives of this study were to determine the serum and pulmonary disposition of tilmicosin in foals and to investigate the in vitro activity of the drug against Rhodococcus equi and other common bacterial pathogens of horses. A single dose of a new fatty acid salt formulation of tilmicosin (10 mg/kg of body weight) was administered to seven healthy 5- to 8-week-old foals by the intramuscular route. Concentrations of tilmicosin were measured in serum, lung tissue, pulmonary epithelial lining fluid (PELF), bronchoalveolar lavage (BAL) cells, and blood neutrophils. Mean peak tilmicosin conc...
Norman TE, Batista M, Lawhon SD, Zhang S, Kuskie KR, Swinford AK, Bernstein LR, Cohen ND.This study's objective was to determine the in vitro antimicrobial activities of gallium maltolate (GaM) and 20 other antimicrobial agents against clinical equine isolates of Corynebacterium pseudotuberculosis. The growth of cultured isolates was not inhibited by any concentration of GaM. MIC data revealed susceptibility to commonly used antimicrobials.
Benson BM, Byron CR, Pondenis H, Stewart AA.To investigate, in vitro, the effects of radial shock waves on the release of nitric oxide (NO) and synthesis of prostaglandin E2 (PGE2) and glycosaminoglycan (GAG), and liberation of GAG, from equine articular cartilage explants. Methods: Equine cartilage from normal metacarpophalangeal and metatarsophalangeal joints was exposed to radial shock waves at various impulse doses and then maintained as explants in culture for 48 h. Shock waves were delivered at 1,876 Torr pressure and a frequency of 10 Hz. Treatment groups consisted of a negative control group, or application of 500, 2,000, or 4,0...
Mirzai S, Safi S, Mossavari N, Afshar D, Bolourchian M.The present study was conducted to establish a Loop-mediated isothermal amplification (LAMP) technique for the rapid detection of B. mallei the etiologic agent of glanders, a highly contagious disease of equines. A set of six specific primers targeting integrase gene cluster were designed for the LAMP test. The reaction was optimized using different temperatures and time intervals. The specificity of the assay was evaluated using DNA from B.pseudomallei and Pseudomonas aeruginosa. The LAMP products were analyzed both visually and under UV light after electrophoresis. The optimized conditions w...
Tesena P, Korchunjit W, Taylor J, Wongtawan T.Gastric tissue biopsy and gene expression analysis are important tools for disease diagnosis and study of the physiology of the equine stomach. However, RNA extraction from gastric biopsy samples is a complex procedure because the samples contain low quantities of RNA and are contaminated with mucous protein and bacterial flora. The objectives of these studies were to compare the performance of RNA extraction methods and to investigate the sensitivity of commercial qPCR master mixes for gene expression analysis of gastric biopsy samples. Three commercial RNA extraction methods (TRIzol, GENEzol...
Amavisit P, Browning GF, Lightfoot D, Church S, Anderson GA, Whithear KG, Markham PF.A rapid polymerase chain reaction (PCR) assay was developed for detecting Salmonella in faeces of horses and assessed on samples from horses admitted to a veterinary hospital. Direct detection was achieved by amplification of part of ompC after extraction of DNA from faeces using a spin column method to reduce the amount of inhibitory substances in samples. An internal positive control was included to detect false negative results. While the sensitivity of the PCR assay was less than culture when assessed on faeces inoculated with Salmonella, its sensitivity on faecal samples obtained from hor...
Byron CR, Benson BM, Stewart AA, Pondenis HC.To evaluate the effects of methylprednisolone acetate (MPA) on proteoglycan production by equine chondrocytes and to investigate whether glucosamine hydrochloride modulates these effects at clinically relevant concentrations. Methods: Articular cartilage with normal gross appearance from metacarpophalangeal and metatarsophalangeal joints of 8 horses (1 to 10 years of age). Methods: In vitro chondrocyte pellets were pretreated with glucosamine (0, 1, 10, and 100 microg/mL) for 48 hours and exposed to MPA (0, 0.05, and 0.5 mg/mL) for 24 hours. Pellets and media were assayed for proteoglycan prod...
Medina-Torres CE, Mason SL, Floyd RV, Harris PA, Mobasheri A.The aim of this study was to determine if hypoxia and the hypoxia mimetic cobalt chloride regulate the activity of matrix metalloproteinase (MMP)-2 and -9 in cultures of equine hoof keratinocytes. These effects were assessed in primary cultures of laminar keratinocytes using gelatin zymography. Incubation of keratinocytes with cobalt chloride significantly increased the levels of active MMP-2 compared to untreated controls. Hypoxia significantly increased the expression of active MMP-2 and -9 in keratinocyte cultures. This up-regulation was observed after 6h and peaked at 24h. The study findin...
Rigby SL, Barhoumi R, Burghardt RC, Colleran P, Thompson JA, Varner DD, Blanchard TL, Brinsko SP, Taylor T, Wilkerson MK, Delp MD.Persistent, postmating endometritis affects approximately 15% of mares and results in reduced fertility and sizable economic losses to the horse-breeding industry. Mares that are susceptible to postmating endometritis have delayed uterine clearance associated with reduced uterine contractility. Unfortunately, the mechanism for reduced uterine contractility remains an enigma. The present study examined the hypothesis that mares with delayed uterine clearance have an intrinsic contractile defect of the myometrium. Myometrial contractility was evaluated in vitro by measuring isometric tension gen...