Tissue in horses refers to the various types of biological material that make up the body of the animal, including muscle, connective, epithelial, and nervous tissues. Each type of tissue has specific functions and characteristics, contributing to the overall physiology and health of the horse. Muscle tissue is responsible for movement and locomotion, connective tissue provides structural support and protection, epithelial tissue covers body surfaces and lines cavities, and nervous tissue is involved in transmitting signals for communication and coordination within the body. The study of equine tissue encompasses aspects such as growth, repair, and response to injury or disease. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and pathology of different tissue types in horses, offering insights into their role in equine health and disease management.
Dabareiner RM, Snyder JR, White NA, Pascoe JR, Harmon FA, Gardner I, Woliner MJ, Pinney D, Sullins KE.Microvascular permeability of the jejunum of clinically normal equids and microvascular permeability associated with 60 minutes of ischemia (25% baseline blood flow) and subsequent reperfusion were investigated. Eight adult horses were randomly allotted to 2 equal groups: normal and ischemic/reperfusion injury. Lymphatic flow rates, mesenteric blood flow, and lymph and plasma protein concentrations were determined at 15-minute intervals throughout the study. Microvascular permeability was determined by estimates of the osmotic reflection coefficient, which was determined when the ratio of lymp...
Moore RM, Muir WW, Granger DN.Restoration of blood flow after a period of intestinal ischemia is necessary to maintain cell function and viability; however, the reintroduction of oxygen can initiate a cascade of events that exacerbates tissue injury. Intestinal I-R injury is manifested as increased microvascular and mucosal permeability, and mucosal necrosis. Reperfusion injury begins with the accumulation of hypoxanthine from ATP metabolism and the conversion of XDH to XO during ischemia. Upon reperfusion, the XO catalyzes the conversion of hypoxanthine to superoxide radicals in the presence of oxygen. Superoxide radicals...
Sams AE, Minor RR, Wootton JA, Mohammed H, Nixon AJ.Chondrocyte-laden collagen scaffolds were evaluated in extensive cartilage defects in an equine model. Arthroscopic techniques were used to implant a chondrocyte-collagen culture product in 15-mm defects in the lateral trochlear ridge of the femoropatellar joint of 12 horses. Ungrafted control defects were formed in the opposite joint. Groups of six horses were terminated at 4 and 8 months after implantation and the repair sites, adjacent cartilage, and remote cartilage within each femoropatellar joint examined biochemically. Eight months following surgery the relative proportions of type II c...
Baba K, Kawamura T, Shibata M, Sohirad M, Kamiya A.The aim of this computer simulation study is to evaluate the efficiency of capillary networks in the skeletal muscle for oxygen (O2) delivery to tissue for all mammals. This was performed by: (1) employing Krogh's cylinder model for the capillary-tissue system and the minimum volume model for the vascular system, (2) allometrically assessing the muscle blood flow and O2 consumption rate (the main input data) in the resting and exercising states as power functions of body weight from the data reported for several mammals, and (3) calculating the cost-performance of the system from the ratio (ma...
Dowling PM, Wilson RC, Tyler JW, Duran SH.The pharmacokinetics of ciprofloxacin was investigated in healthy, mature ponies. Ciprofloxacin was administered intravenously to six ponies at a dose of 5 mg per kg body weight. Seven days later, ciprofloxacin was administered orally to each pony at the same dose. Intravenous ciprofloxacin concentration vs. time data best fit a two-compartment open model with first-order elimination from the central compartment. Mean plasma half-life, based on the terminal phase, was 157.89 min (harmonic mean). Total body clearance of ciprofloxacin was 18.12 +/- 3.99 mL/min/kg. Volume of distribution at stead...
Loke WK, Khor E.Shrinkage temperature is most often used to report the degree of cross-linking in glutaraldehyde-fixed animal tissue for use in bioprosthetic heart valve fabrication. Present practice utilizes the measurement of hydrothermal shrinkage observed when a sample is subjected to a temperature programme. This measurement at best gives a general indication of the efficiency of the treatment, i.e. the extent of cross-linking in the tissue. When differential scanning calorimetry has been used, the ambiguity arising from the scant reporting of the protocols used does not permit easy comparison of experim...
von Rotz A, Friess AE.Sinus hairs, which are tactile organs of most mammals, are differentiated into cavernous and sinus types. The horse has the cavernous type. Horse lower lips were perfused in diluted Karnovsky's fixative and sinus hair processed for scanning electron microscopy. Anastomosing trabeculae of different thickness and shape originate from the internal connective tissue layer and extend to the external layer, thus forming a dense meshwork suspending the hair root like a net. However, many of the distal trabeculae do not reach the external wall of the blood sinus but end in a finger-like knob within th...
Lennard SN, Stewart F, Allen WR.Placentation in equids involves two types of trophoblast: a minor invasive component, the chorionic girdle, that gives rise to transient endocrine structures known as endometrial cups, and a major non-invasive component, the allantochorion, that forms the diffuse, microcotyledonary placenta. Growth factors are likely to be important in controlling these complex events at implantation and this study describes the use of in situ hybridization and northern blotting techniques to monitor expression of insulin-like growth factor II (IGF-II) in the fetus and placenta of the horse (Equus caballus), u...
Gomez-Villamandos RJ, Santisteban Valenzuela JM, Ruiz Calatrava I, Gomez-Villamandos JC, Avila Jurado I.A study was made of the effects of low-level laser irradiation on the cicatrization of superficial wounds in the pharyngeal mucosa of the horse. Methods: Duplicate pharyngeal mucosal ulcers were induced in 12 Spanish horses with submucosal injection of sulfuric acid. A fibroendoscope and an He-Ne laser were used to treat one of the ulcers and the second ulcer in each animal was left untreated, serving as a control. Biopsy samples for the histological study were taken after the seventh laser therapy session from the two animals. Results: Irradiated lesions cicatrized at 10.5 days and nonirradia...
Schrenzel MD, Ferrick DA.Horse (Equus caballus) T-cell receptor alpha (TCRA), gamma (TCRG), and delta (TCRD) chain genes were isolated from a cDNA library and characterized. Five unique TCRAV families, including four full-length sequences, five distinct TCRAJ genes, and a single TCRAC gene were identified. TCRAV genes had closest homology with human sequences and least similarity to rat genes. Among eight horse TCRG genes, two distinct constant region genes with considerable variation in the connecting region were identified, but no variable or joining genes were present. Southern blot hybridization confirmed the pres...
Collatos C, Barton MH, Schleef R, Prasse KW, Moore JN.Much of the pathophysiology associated with equine gastrointestinal diseases is attributed to the effects of endotoxin on haemostasis. Because little is known about the responses of the equine fibrinolytic system to endotoxin, regulation of the system was investigated. Tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type-1 (PAI-1) were identified as the primary plasminogen activator and plasminogen activator inhibitor, respectively, in equine blood. Under experimental conditions, the equine fibrinolytic system responded to endotoxin in a manner similar to that repo...
Trostle SS, Wilson DG, Stone WC, Markel MD.The purposes of this study were to mechanically determine the optimal tissue bite size and to evaluate seven suture materials at their largest commercially available size for breaking strength and stiffness using cadaveric adult equine linea alba. Soft tissues were removed from the abdominal fascia of 16 adult horses. Individual test sections were created from the entire linea alba and labeled (1 through 6) starting at the umbilicus and extending craniad. A single biomechanical test was performed on each test section. Tissue bite size (3, 6, 9, 12, 15, 18, and 21 mm) significantly altered brea...
Asahina M, Murakami K, Ajito T, Goryo M, Okada K.The tissues of an 8-year-old thoroughbred castrated male horse with equine lymphoma were examined immunohistochemically. Neoplastic masses were observed in the mediastinum, mesenteric lymph nodes, gastric mucosa and serosa, liver capsule, and spleen capsule with associated lymph nodes. Histopathologically, the neoplastic cells were seen to consist predominantly of a mixture of well differentiated small and large types. Immunohistochemically, the small lymphoid cells were MHC class IIlow+ and PanT- and the large lymphoid cells were MHC class IIhigh+ and PanT-. These findings revealed that the n...
Brown CC, Meyer RF, Grubman MJ.In a retrospective study, a negative-sense digoxigenin-labeled RNA probe, corresponding to the gene encoding nonstructural protein-1 of African horse sickness virus (AHSV) serotype 4, was applied to formalin-fixed, paraffin-embedded tissue taken from horses in the terminal stages of infection with AHSV. Fifteen infected ponies and one noninfected control were studied. Ponies exhibited a range of clinical signs and lesions. Thirteen ponies were infected with serotype 4, one with serotype 1, and one with serotype 2. Ponies were monitored clinically and euthanatized when severely clinically ill. ...
Vail TB, Trotter GW, Powers BE.The osteoinductive capability of four particle sizes of equine demineralized bone matrix (DBM) was evaluated. Matrix particles were implanted in brachiocephalicus muscle pouches in six horses and were harvested 8 weeks later. Matrix particle sizes of 2.0 mm3 to 4.0 mm3 and 5.0 mm3 to 10.0 mm3 were associated with osteoinductive activity and minimal signs of local inflammation. The two smaller particle sizes (0.425 mm3 to 0.850 mm3 and 0.850 mm3 to 2.0 mm3) were minimally osteoinductive and were associated with a greater local inflammatory response. Microscopic events associated with new bone p...
Pollitt CC.In the equine hoof, the basement membrane connects the heavily keratinised hoof wall to the dense connective tissue of the distal phalanx, a region able to withstand considerable mechanical stress. This study investigated the properties of this important anatomical and physiological structure. In contrast to haematoxylin and eosin, the connective tissue stains, periodic acid Schiff, periodic acid silver methenamine and Azan showed good resolution of lamellar basement membrane. The lamellar basement membrane cross-reacted with mouse monoclonal antibodies raised against human laminin, thereby pr...
Sonea IM, Bowker RM, Robinson NE, Broadstone RV.Distribution of pulmonary nerves immunoreactive for either substance P or calcitonin gene-related peptide was determined, using immunohistochemical methods on healthy lungs from adult equids. The overall patterns of distribution of substance P and calcitonin gene-related peptide-like immunoreactivity were similar. Distribution of immunoreactive nerves was not uniform throughout the lungs; nerve fibers immunoreactive for these peptides were more frequently observed near the hilus of the lung than in the caudal lobes or in the periphery of the lung. Nerve fibers immunoreactive for substance P or...
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...
Jones DL, Barber SM, Jack SW, Doige CE.Gross and microscopic effects of arthroscopic partial synovectomy on synovium and articular cartilage of middle carpal joints were studied in 15 horses. A 7-mm diameter motorized synovial resector was inserted into each middle carpal joint and arthroscopic partial synovectomy and lavage or arthroscopic lavage alone was performed. Study periods were 0 (three horses), 16 (three horses), and 30 days (six horses). No gross evidence of degenerative joint disease was observed at day 16 or 30. At 30 days, resected areas lacked villi and there was deposition of fibrin on the synovial surface with vary...
Pearson GT.The architecture and neurochemistry of the enteric nervous system was studied by use of whole-mount preparations obtained by microdissection of the horse jejunum. A myenteric plexus and two plexuses within the submucosa were identified. The external submucosal plexus lying in the outermost region of the submucosa had both neural and vascular connections with the inner submucosal plexus situated closer to the mucosa. Counts of neurones stained for NADH-diaphorase demonstrated the wide variation in size, shape and neurone content of individual ganglia in both the external and internal submucosal...
O'Keefe JS, Julian A, Moriarty K, Murray A, Wilks CR.A detection system incorporating the polymerase chain reaction was compared with the use of histopathology and virus isolation to determine the presence of equid herpesvirus type 1 or equid herpesvirus type 4 in equine tissues submitted to a diagnostic laboratory. When the polymerase chain reaction was performed, these tissues had been stored for up to 3 years. Thirty-eight tissues representing 14 cases had been stored embedded in paraffin wax. Analysis of these tissues using the PCR gave predictive values of 1.0 and 0.91 for a positive and negative result respectively, and sensitivity and spe...
Wilson DV, Patterson JS, Stick JA, Provost PJ.The role of platelet-activating factor (PAF) in mediating the colonic damage that develops after large-colon torsion was studied in 14 ponies. Morphologic changes in areas of the ascending colon and selected abdominal and thoracic viscera after 1 hour of large-colon torsion and 3 to 5 hours of reperfusion were determined, as well as the protective effects of systemic administration of a specific PAF antagonist (WEB 2086). Ponies were selected then allocated at random and in equal numbers to 2 groups that received 1 of 2 treatments prior to induction of large-colon torsion: group 1--control (sa...
Edington N, Welch HM, Griffiths L.Equid herpesviruses 1 or 4 (EHV-1 or -4) were isolated by cocultivation from 60% of 40 horses examined at slaughter. The lymph nodes draining the respiratory tract were the most common source of virus. EHV-1 or EHV-4 was never isolated from the trigeminal ganglia (SLG). The polymerase chain reaction (PCR) detected virus in 87.5% of bronchial lymph nodes and a similar level in the trigeminal ganglia that were examined. By both assays approximately one third of the positive animals harboured both viruses. Equid herpesvirus 2 (EHV-2) was isolated from all but one of the horses and from > 75% o...
Hendrickson DA, Nixon AJ, Erb HN, Lust G.Equine neonatal chondrocytes were cultured in three-dimensional fibrin matrices under conditions of immediate implantation or implantation following monolayer culture for 6 days, and 3 cell concentrations (1 x 10(5), 1 x 10(6), and 5 x 10(6) chondrocytes/cm3). Equine fibrinogen was collected by cryoprecipitation and polymerized by use of activated bovine thrombin. The fibrin implants were harvested and analyzed histologically and biochemically at 3, 7, and 14 days after the chondrocytes were implanted in fibrin. The differentiation ratio (ratio of rounded, chondrocyte-like cells to stellate, f...
Barr AR, Duance VC, Wotton SF, Waterman AE, Holt PE.Cyanogen bromide was used to solubilise and specifically fragment purified equine Type I and II collagen and equine articular surface repair tissue. The resultant peptides were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and quantified by densitometric scanning. Measurement of the relative amounts of the peptides alpha 2(I) CB3, 5 and alpha 1(II)CB10 provided an accurate method of establishing the ratio of Type I to Type II collagen in mixtures of purified equine collagens. The method was sensitive to 6% Type II collagen when the band areas were corrected for peptid...
Oriol JG, Sharom FJ, Betteridge KJ.The embryonic capsule, which covers the equine blastocyst after it loses its zona pellucida, is composed of mucin-like glycoproteins. In the present study, we investigated both macroscopic and molecular changes in the capsule during development. The weight of the capsule increased from day 11-12 of pregnancy and reached a maximum at about day 18, coinciding with the time during which the conceptus migrates extensively throughout the uterus. The sialic acid content of the capsule declined markedly from about day 16, the time of conceptus 'fixation' in the uterus, which suggests a unique develop...
Murray MJ, Mahaffey EA.Specimens of grossly normal gastric stratified squamous epithelial mucosa adjacent to the margo plicatus on the right side and along the greater curvature were obtained from 7 foetuses, 10 term foals and 12 foals 2-35 days old. Gastric squamous epithelium from the foetuses changed markedly during gestation. At 150-270 days, the epithelium was 8-10 cells thick, with a single layer of basal cells. Epithelial cells were polyhedral and had abundant clear or slightly stained cytoplasm. In the 300-day foetus the basal layer was thicker, epithelial cells were polyhedral, and there was a flattened 1 c...
Okamoto Y, Minami S, Matsuhashi A, Sashiwa H, Saimoto H, Shigemasa Y, Tanigawa T, Tanaka Y, Tokura S.The sponge-, cotton-, and flake-type remedies made of chitin (chitin-sponge, chitin-cotton, and chitin-flake, respectively), and non-woven fabric of polyester (NWF) composited with chitin (chitin-NWF) were applied to various types of trauma, abscess, surgical tissue defect and herniorrhaphy in 147 clinical cases including 72 dogs, 38 cows, 33 cats, 2 rabbits, one monkey and one horse. Chitin-sponge was applied in 30 cases as filling agent of surgical tissue defect, and in 25 cases of trauma, 31 cases of abscess as wound dressing or tissue defect filling agent. In 77 out of 86 cases (89.5%), go...
Canè V, Botti P, Soana S.The influence of pulsed low-frequency electromagnetic fields (PEMFs) on bone formation was investigated in studies of the healing process of transcortical holes, bored at the diaphyseal region of metacarpal bones of six adult horses, exposed for 30 days to PEMFs (28 G peak amplitude, 1.3 ms rise time, and 75 Hz repetition rate). A pair of Helmholtz coils, continuously powered by a pulse generator, was applied for 30 days to the left metacarpal bone, through which two holes, of equal diameter and depth, had been bored at the diaphyseal region. Two equal holes, bored at the same level in the rig...
Balazs EA, Denlinger JL.Viscosupplementation is a new medical concept that has as its therapeutic goal the restoration of rheological homeostasis in pathological structures such as osteoarthritic joints. When the normal viscoelasticity of a solid tissue compartment or the elastoviscosity of a liquid tissue compartment is decreased under pathological conditions, normal function and regenerative processes are impaired. By introducing viscosupplementary devices, the normal rheological state of such compartments is restored or augmented. These devices stay in the tissue compartment for various periods of time, depending ...
Södersten F, Hultenby K, Heinegård D, Johnston C, Ekman S.This is a descriptive study of tendon pathology with different structural appearances of repair tissue correlated to immunolocalization of cartilage oligomeric matrix protein (COMP) and type I and III collagens and expression of COMP mRNA. The material consists of nine tendons from seven horses (5-25 years old; mean age of 10 years) with clinical tendinopathy and three normal tendons from horses (3, 3, and 13 years old) euthanized for non-orthopedic reasons. The injured tendons displayed different repair-tissue appearances with organized and disorganized fibroblastic regions as well as areas o...
Rodrigues NL, Doré M, Doucet MY.To characterize the expression of the cyclooxygenase (COX)-1 and COX-2 isoforms in naturally occurring ulcers of the nonglandular portion of the stomach in horses. SPECIMEN POPULATION: 38 specimens from ulcerated stomachs and 10 specimens from healthy stomachs. Methods: Specimens were collected at an abbatoir; for each specimen of squamous gastric mucosa, 1 portion was fixed in neutral-buffered 10% formalin for immunohistochemical analysis and another was frozen at -70 degrees C for immunoblotting analysis. Immunoreactivity to 2 antibodies, MF241 (selective for COX-1) and MF243 (selective for ...
Douglas JE, Mittal C, Thomason JJ, Jofriet JC.During normal weight-bearing and locomotion, the equine hoof wall deforms in a consistent pattern; the proximal dorsal wall rotates caudo-ventrally about the distal dorsal border and there is latero-medial flaring posteriorly. The aim of this study is to examine whether there are regional differences in the modulus of elasticity of hoof wall material and whether such differences correlate with the pattern of deformation which occurs in vivo. The modulus of elasticity of equine hoof wall was determined in tension and compression for samples from six forefeet. Samples were tested at the mid-poin...
Costa D, Leiva M, Naranjo C, Ríos J, Peña MT.To evaluate microbiological, histological, and ultrastructural characteristics of short-term cryopreserved (STC) equine corneoscleral tissue (7 years). Methods: Thirty-four healthy equine globes. Methods: After a decontamination protocol, globes were enucleated and stored at -20°C in broad-spectrum antibiotics. Corneoscleral tissue was evaluated at different storage periods: 1 month-1 year (20 eyes) and 7-9 years (12 eyes). Two eyes were used as controls. Microbiologic study included direct (blood, McConkey, and Sabouraud agars) and enrichment (brain-heart infusion broth) cultures. Cryopr...
Kasapi MA, Gosline JM.The mechanical properties of fully hydrated equine hoof wall were examined at various loading rates in compact tension (CT) fracture, tensile and three-point bending dynamic tests to determine possible effects of hoof wall viscoelasticity on fracture toughness and tensile parameters. Four cross-head rates were used in CT tests: 1.7 x 10(-5), 1.7 x 10 (-3), 1.7 x 10(-2) and 2.5ms-1; four strain rates were used in tensile tests: 1.6 x 10(-3), 3.2 x 10(-2), 0.33 and 70s(-1). Speeds for the highest test rates were achieved using a large, custom-built impact pendulum. Bending test frequencies range...
Velloso Alvarez A, Wooldridge AA, Fuller J, Shrader SM, Mansour M, Boone LH.No studies have evaluated the effect of culture in serum-free media (SF) vs. media supplemented with equine serum (ES) on co-culture of synovial membrane and cartilage tissue explants. The study objective was to evaluate the effects of equine serum supplementation on induced production of inflammatory and catabolic mediators from articular cartilage and synovial explants while in co-culture. Articular cartilage and synovial membrane explants were harvested from femoropatellar joints of five adult horses. Cartilage and synovial explants were harvested from the stifle of five horses, placed in c...
Dunay MP, Németh T, Makra Z, Izing S, Bodó G.In the present series of cases, 8 laparoscopic cryptorchidectomies and 4 laparoscopic ovariectomies were carried out in sedated standing horses. Sedation involved a lesser anaesthesiological risk than does general anaesthesia. As compared to laparotomic exposure, the minimally invasive laparoscopic intervention provided better visualisation, shorter operative time and faster recovery. The blood vessels supplying the testes and ovaries and the suspensory ligaments of the organs were sealed and cut with EnSeal®, an adaptive bipolar electrosurgical blood vessel- and tissue-sealing device. The cl...
Kankavi O, Ata A, Akif Ciftcioglu M.The presence of surface-active material in the lung alveolus has been known for several decades as being essential for normal lung function. The host defense and controlling inflammatory processes of the lung are the major functions of SP-A and SP-D. SP-A and SP-D were originally demonstrated in alveolar type II cells, but recent studies have shown extrapulmonary expression of SP-A and SP-D indicating systemic roles of these proteins. Present study describes the presence of SP-A and SP-D in the stallion genital tract, prepuce, prostate, testis, and seminal vesicle using Western blotting and im...
The objective of this study was to graft autologous mesenchymal stem cells (MSCs) at the site of surgical repair of a soft palate defect in an adult horse in an attempt to improve wound healing and to investigate whether the transplanted MSCs would integrate into the soft palate structure and participate in regeneration. Bone marrow was collected from an adult horse with a full-thickness soft palate defect. The MSCs were isolated, cultured in monolayers, and labeled with 5-bromo-2-desoxymidine (BrdU) and chloromethylbenzamido-DiI-derived (cm-DiI) before transplantation. The soft palate defect ...
De Angelis E, Barilli A, Saleri R, Rotoli BM, Ravanetti F, Ferrari F, Ferrari L, Martelli P, Dall'Asta V, Borghetti P.Due to the importance of joint disease and ostearthritis (OA) in equine athletes, new regenerative treatments to improve articular cartilage repair after damage are gaining relevance. Chondrocyte de-differentiation, an important pathogenetic mechanism in OA, is a limiting factor when differentiated articular chondrocytes are used for cell-based therapies. Current research focuses on the prevention of this de-differentiation and/or on the re-differentiation of chondrocytes by employing different strategies in vitro and in vivo. Articular chondrocytes normally live in a condition of higher osmol...
Aradaib IE.A nested reverse transcriptase (RT) polymerase chain reaction (RT-PCR), for rapid detection of African horse sickness virus (AHSV) double-stranded ribonucleic acid (dsRNA) in cell culture and tissue samples, was developed and evaluated. Using an outer pair of primers (P1 and P2), selected from genome segment three of AHSV serotype 6 (AHSV-6), the RT-PCR-based assay resulted in amplification of a 890 base pair (bp) primary PCR product. RNAs from the nine vaccine strains of AHSV, and a number of AHSV field isolates including the Central African isolates of AHSV-9 and AHSV-6, propagated in cell c...
Dubuc V, Laverty S, Richard H, Doré M, Theoret C.There is a growing interest in the scientific community to use computer-based software programs for the quantification of cells during physiological and pathophysiological processes. Drawbacks of computer-based methods currently used to quantify immunohistochemical staining are the complexity of use, expense of software and overly-simplified descriptions of protocol thereby limiting reproducibility. The precise role of mast cells in equine cutaneous wound healing is unknown. Given the contribution of mast cells to the chronic inflammation observed in human keloid, a pathology similar to exuber...
Karagianni AE, Kapetanovic R, McGorum BC, Hume DA, Pirie SR.Alveolar macrophages (AMs) constitute the first line of defence in the lung of all species, playing a crucial role in the regulation of immune responses to inhaled pathogens. A detailed understanding of the function and phenotype of AMs is a necessary pre-requisite to both elucidating their role in preventing opportunistic bacterial colonisation of the lower respiratory tract and developing appropriate preventative strategies. The purpose of the study was to characterise this important innate immune cell at the tissue level by making functional and phenotypic comparisons with peritoneal macrop...
Williams MR.Rats were injected intradermally with rabbit anti-ovalbumin serum and 3 hours later were challenged intravenously with ovalbumin and Evans Blue dye. Inflammatory lesions were produced within 20 minutes and their size was markedly dose-dependent. Attempts were made to interfere with this passive cutaneous anaphylaxis (PCA) by admixture of normal IgG with the rabbit anti-ovalbumin to measure the relative tissue binding affinities of IgG from various species. It was found that normal IgG from any of the species tested had an enhancing effect on PCA in rats. These immunoglobulins serially arranged...
Wertz PW, Downing DT.The lipids of horse hoof have been analyzed by quantitative thin-layer chromatography. The major components include cholesterol (37-40%), six groups of ceramides (10-15%), and cholesteryl sulfate (15-20%). Free fatty acids are abundant (15.8%) in the outer fully keratinized hoof, but are present at only low levels (3.1%) in the softer hyponychium. The material identified as cholesteryl sulfate was isolated by preparative thin-layer chromatography and characterized by a combination of chemical, chromatographic, and spectroscopic methods. The infrared spectrum of the isolated material had absorp...
Ueki M, Takeshita H, Fujihara J, Ueta G, Nakajima T, Kominato Y, Kishi K, Iida R, Yasuda T.Equine (Equus caballus) deoxyribonuclease I (DNase I) was purified from the parotid gland, and its 1295-bp cDNA was cloned. The mature equine DNase I protein consisted of 260 amino acid residues. The enzymatic properties and structural aspects of the equine enzyme were closely similar to those of other mammalian DNases I. Mammalian DNases I are classified into three types--pancreatic, parotid and pancreatic-parotid-based on their tissue distribution; as equine DNase I showed the highest activity in the parotid gland, it was confirmed to be of the parotid-type. Comparison of the susceptibility ...
Sievers H, Hiebl B, Hünigen H, Hirschberg RM.Blood supply is an important factor for the normal function of the equine hoof, but earlier studies present conflicting data on functional characteristics of its angioarchitecture. Objective: Emphasis was laid on demonstration of the microvascularisation in the different hoof wall regions, aiming at assessment of specialised vascular structures, e.g. vascular sphincter mechanisms and arteriovenous anastomoses. Methods: The angioarchitecture of the adult pododerma in the equine hoof wall was examined by scanning electron microscopy of micro-corrosion casts assisted by exemplary histological and...
Loux S, Robles M, Chavatte-Palmer P, de Mestre A.Development and the subsequent function of the fetal membranes of the equine placenta require both complex and precise regulation of gene expression. Advancements in recent years in bioinformatic techniques have allowed more extensive analyses into gene expression than ever before. This review starts by combining publically available transcriptomic data sets obtained from a range of embryonic, placental and maternal tissues, with previous knowledge of equine placental development and physiology, to gain insights into key gene families relevant to placentation in the horse. Covering the whole o...
Wattle O.The equine skin and its appendages (chestnut, hoof capsule, ergot, sebaceous glands, sweat glands and hair) consist mainly of keratinocytes. The intermediate filament cytoskeleton of these cells in involved in specialised functions, such as mechanical co-ordination of the cytoskeleton of the cell or tissue. In this study, 7 monoclonal antibodies, one polyclonal antibody and immunoblot analysis were used to characterise cytokeratins (separated by 1- and 2-dimensional gel electrophoresis) from the hoof wall and chestnut. The tissue distribution of these cytokeratins was studied by immunohistoche...
Boos GS, Nobach D, Failing K, Eickmann M, Herden C.A suitable RNA extraction protocol was established to gain high quality RNA from formalin-fixed paraffin-embedded tissues to perform reliable molecular assays either applicable for using FFPE tissue archives or tissues with harsh formalin-fixation. Eighteen FFPE samples from the central nervous system of horses, stored up to 11 years, were used as archive cases. To test the influence of the fixation period, brain, liver, kidney, and skeletal muscle tissue fragments from another horse, were treated either with water or tris-acetate-EDTA buffer after fixation under different timepoints with 10...
Grages AM, Verhaar N, Pfarrer C, Breves G, Burmester M, Neudeck S, Kästner S.In experimental studies investigating strangulating intestinal lesions in horses, different ischaemia models have been used with diverging results. Therefore, the aim was to comparatively describe ischaemia reperfusion injury (IRI) in a low flow (LF) and no flow (NF) model. Under general anaesthesia, 120 min of jejunal ischaemia followed by 120 min of reperfusion was induced in 14 warmbloods. During ischaemia, blood flow was reduced by 80% (LF, n = 7) or by 100% (NF, n = 7). Intestinal blood flow and oxygen saturation were measured by Laser Doppler fluxmetry and spectrophotometry. Clinical, hi...
Warnken T, Brehm R, Feige K, Huber K.The aim of the study was to analyze key proteins of the equine insulin signaling cascade and their extent of phosphorylation in biopsies from muscle tissue (MT), liver tissue (LT), and nuchal AT, subcutaneous AT, and retroperitoneal adipose tissues. This was investigated under unstimulated (B1) and intravenously insulin stimulated (B2) conditions, which were achieved by injection of insulin (0.1 IU/kg bodyweight) and glucose (150 mg/kg bodyweight). Twelve warmblood horses aged 15 ± 6.8 yr (yr), weighing 559 ± 79 kg, and with a mean body condition score of 4.7 ± 1.5 were included in the s...
Rosa MVD, Rosa M, Botteon PTL.This study aimed to evaluate the use of equine amniotic membrane (EAM), frozen indirectly using liquid nitrogen and stored between -10° and -24°C, in the treatment of equine skin lesions. Six healthy female horses, aged 3-10 years, were included in this study. EAM was collected from previously evaluated healthy parturient mares. Wounds were surgically created at the distal ends of the forelimbs. One limb was chosen for treatment, and the contralateral limb was chosen as the control. Pain sensitivity, presence of granulation tissue, secretions, and bleeding after debridement during cleaning w...
McD￮ LA, Esparza Gonzalez BP, Nino-Fong R, Aburto E.Autologous mesenchymal stem cells (MSCs) have been used as a potential cell-based therapy in various animal and human diseases. Their differentiation capacity makes them useful as a novel strategy in the treatment of tissue injury in which the healing process is compromised or delayed. In horses, bone healing is slow, taking a minimum of 6-12 months. The osteogenic capacity of equine bone marrow and muscle MSCs mixed with fibrin glue or phosphate-buffered saline (PBS) as a scaffold is assessed. Bone production by the following groups was compared: Group 1, bone marrow (BM) MSCs in fibrin glue;...
Robertson SA, Andrew SE.To determine if opioid growth factor (OGF, [Met5]enkephalin) and its specific receptor (OGFr) are present in normal cat, dog and horse cornea. Methods: Normal dog, cat and horse. Methods: Corneas were obtained from animals euthanized for reasons unrelated to this project. One cornea from each of three normal cats, dogs and horses was evaluated. The right or left cornea from each animal was chosen randomly. Corneas were harvested and placed in corneal storage media for transport to The M.S. Hershey Medical Center of The Pennsylvania State University where immunocytochemistry techniques were use...
Ludewig T.The purpose of the study was to give a histological picture of the different skin regions of the mammary gland in mares. Special emphasis on the dark coating in the sulcus intermammarius was given. As a result, the dark pigmented udder skin can be subdivided into the skin of the Corpus mammae, the sulcus intermammarius and the teat skin. In the sulcus intermammarius the whole epidermis was considerably thicker than usual, especially the stratum corneum (up to 70 layers of cornified layers) and the stratum spinosum. In general, the squamous keratinocytes were unusually large. The histological p...
Bristol DG, Cullen J.Six animals were used to compare simple interrupted, simple continuous, and stapled techniques for end-to-end rotated small colon anastomoses. Three ponies were evaluated three days after surgery for adhesion formation and luminal diameter at each anastomosis site. Two ponies and one horse were evaluated 14 days after surgery for adhesion formation. All anastomosis sites were examined histologically for alignment of tissue planes, and evidence of inflammation. No single technique was superior in all areas examined. While only three of the nine anastomoses had mild fibrinous adhesions at three ...
Brown CC, Meyer RF, Grubman MJ.In a retrospective study, a negative-sense digoxigenin-labeled RNA probe, corresponding to the gene encoding nonstructural protein-1 of African horse sickness virus (AHSV) serotype 4, was applied to formalin-fixed, paraffin-embedded tissue taken from horses in the terminal stages of infection with AHSV. Fifteen infected ponies and one noninfected control were studied. Ponies exhibited a range of clinical signs and lesions. Thirteen ponies were infected with serotype 4, one with serotype 1, and one with serotype 2. Ponies were monitored clinically and euthanatized when severely clinically ill. ...
Scott WM, Fowler JD, Matte G, Allen AL, Wilkinson AA, Bailey JV, Fretz PB.To investigate neutrophil accumulation after ischemia and reperfusion (IR) in microvascular tissue flaps in horses. Methods: Randomized controlled experiment. Methods: A total of 8 horses between 1 and 10 years of age, 4 of each sex. Methods: Control and experimental myocutaneous island flaps based on the superficial branch of the deep circumflex iliac vessels were dissected on each horse. Atraumatic vascular clamps were applied to the pedicle of the experimental flap for 90 minutes and then removed to allow reperfusion. Based on the assumption that rapid infiltration of neutrophils into affec...
Pollitt CC.In the equine hoof, the basement membrane connects the heavily keratinised hoof wall to the dense connective tissue of the distal phalanx, a region able to withstand considerable mechanical stress. This study investigated the properties of this important anatomical and physiological structure. In contrast to haematoxylin and eosin, the connective tissue stains, periodic acid Schiff, periodic acid silver methenamine and Azan showed good resolution of lamellar basement membrane. The lamellar basement membrane cross-reacted with mouse monoclonal antibodies raised against human laminin, thereby pr...
