Fibrosis in horses refers to the formation of excess fibrous connective tissue as a reparative or reactive process following injury or inflammation. This condition can affect various organs and tissues, including the lungs, liver, and skin, leading to impaired function and structural changes. Fibrosis is characterized by the excessive deposition of extracellular matrix components, such as collagen, which can result in tissue stiffness and scarring. In equine medicine, fibrosis can be associated with chronic conditions such as equine asthma or hepatic disease. This page compiles peer-reviewed research studies and scholarly articles that investigate the mechanisms, diagnosis, and management of fibrosis in horses, offering insights into its impact on equine health and potential therapeutic approaches.
Niedermaier G, Poth T, Gehlen H.Two warmblood horses with a history of chronic weight loss and inappetence were referred to the Faculty of Veterinary Medicine, Ludwig-Maximilians University of Munich, Germany, for further examination. The clinical signs in horse 1 were fever, tachycardia and tachypnoea, and chronic ulcerative keratopathy of both eyes. Horse 2 had severe oral ulcerations and was coughing during feeding. In both horses, increased bronchovesicular sounds were heard during auscultation of the lungs. Laboratory findings included mild anaemia, lymphopenia and hypoalbuminaemia. Radiographic examination of the thora...
Matsuda K, Tabata S, Kawamura Y, Kurosawa T, Yoshie N, Taniyama H.Ectopic bone formation in the left atrioventricular valves and cardiac fibroskeleton, with systemic circulatory disturbance, is reported in a 4-year-old crossbred heavy horse. Microscopically, there was fibrosis, chondral metaplasia and mature bone, with bone marrow within the left atrioventricular cusps and in the annuli of the aortic and right atrioventricular valves.
Plummer CE, Ollivier F, Kallberg M, Brooks D, Barrie K, Utter M, Gelatt K.Amniotic membrane transplantation (AMT) is an effective clinical therapy for reconstruction of the ocular surface in human and veterinary patients. Amnion is avascular and strong, contains antiangiogenic and antiinflammatory properties and growth factors, and has properties that prevent or decrease fibrosis in healing tissue. Indications for its use are steadily growing and include grafting to replace diseased, missing or excised tissue, patching to support diseased tissue during the healing process and as a substrate for the expansion of epithelial cells for transplantation to the cornea. AMT...
Derksen FJ, Williams KJ, Pannirselvam RR, de Feijter-Rupp H, Steel CM, Robinson NE.Regional veno-occlusive remodelling of pulmonary veins in EIPH-affected horses, suggests that pulmonary veins may be central to pathogenesis. The current study quantified site-specific changes in vein walls, collagen and haemosiderin accumulation, and pleural vascular profiles in the lungs of horses suffering EIPH. Objective: In the caudodorsal lung regions of EIPH-affected horses, there is veno-occlusive remodelling with haemosiderosis, angiogenesis and fibrosis of the interstitium, interlobular septa and pleura. Methods: Morphometric methods were used to analyse the distribution and accumula...
Miragliotta V, Lefebvre-Lavoie J, Lussier JG, Theoret CL.Horses suffer from a debilitating impediment in repairing wounds located on the lower limb that leads to the development of a fibroproliferative disorder (exuberant granulation tissue). This condition is a source of wastage since it often forces retirement from competition. Treatments that resolve or prevent this condition are still lacking, maybe due to deficient knowledge of the underlying molecular mechanisms. Fibroblast-to-myofibroblast conversion is an essential step allowing contraction during wound repair and is accompanied by an increase in OB-cadherin expression. Objective: To clone e...
Muñoz JA, Marcoux M, Picandet V, Theoret CL, Perron MF, Lepage OM.Palatal sclerotherapy using sodium tetradecyl sulfate has been suggested as a treatment for dorsal displacement of the soft palate in young Standardbred horses. The present study evaluated histological and biomechanical changes in the equine soft palate following trans-endoscopic treatment with a low dose of this compound. Two horses were euthanased and examined at 2 weeks and at 1, 2, 4 and 6 months post-sclerotherapy, while two further horses served as untreated controls. The technique was easily performed in all cases without major complications. On histological examination there was no evi...
Clutterbuck AL, Harris P, Allaway D, Mobasheri A.The extracellular matrix (ECM) of connective tissue is constantly being remodelled to allow for growth and regeneration. Normal tissue maintenance requires the ECM components to be degraded and re-synthesised in relatively equal proportions. This degradation is facilitated by matrix metalloproteinases (MMPs) and their proteolytic action is controlled primarily by the tissue inhibitors of metalloproteinases (TIMPs). Both MMPs and TIMPs exist in a state of dynamic equilibrium, with a slight excess of one or the other depending on the need for either ECM breakdown or synthesis. Long-term disrupti...
Vannella KM, Moore BB.Idiopathic pulmonary fibrosis (IPF) remains exactly that. The disease originates from an unknown cause, and little is known about the mechanisms of pathogenesis. While the disease is likely multi-factorial, evidence is accumulating to implicate viruses as co-factors (either as initiating or exacerbating agents) of fibrotic lung disease. This review summarizes the available clinical and experimental observations that form the basis for the hypothesis that viral infections may augment fibrotic responses. We review the data suggesting a link between hepatitis C virus, adenovirus, human cytomegalo...
Williams KJ, Derksen FJ, de Feijter-Rupp H, Pannirselvam RR, Steel CM, Robinson NE.Exercise-induced pulmonary hemorrhage (EIPH) is common in horses following intense exertion, occurring in up to 75% of racing Thoroughbreds and Standardbreds. In spite of this, the pathogenesis of EIPH is poorly understood. In 7 racing Thoroughbred horses with EIPH, 6 sections were collected from the left and right lung, representing the cranial, middle, and caudal region of the dorsal and ventral lung (84 sites total). Grossly, both right and left lungs had numerous dark brown to blue-black foci along the caudodorsal visceral pleura. Tissue sections were stained with hematoxylin-eosin, Masson...
Miragliotta V, Lefebvre-Lavoie J, Lussier JG, Theoret CL.Wounds on horse limbs can develop exuberant granulation tissue which resembles the human keloid. Clues gained from the study of over-scarring in horses might help control fibro-proliferative disorders. Objective: The aim of the present study was to clone full-length equine ANXA2 cDNA then to study spatio-temporal expression of ANXA2 and MMP1 mRNA and protein, potential contributors to remodeling, during repair of body (normal) and limb (fibro-proliferative) wounds in an established horse wound model. Methods: Cloning of ANXA2 was achieved by screening size-selected cDNA libraries. Expression w...
Macbeth BJ.A 12-year-old Clydesdale gelding was presented for colic and dysuria. Obstructive urolithiasis and chronic renal disease were diagnosed via transurethral endoscopy and percutaneous ultrasonography. Nephroliths, hydronephrosis, and peri-ureteral fibrosis were present. Surgical intervention was declined and the gelding was managed medically with antibiotics and dietary modification. Urolithiase obstructive, hydronéphrose unilatérale et lithiase rénale probable chez un Clydesdale hongre âgé de 12 ans. Un Clydesdale hongre âgé de 12 ans a été présenté pour colique et dysurie. Une urolit...
Hoffmann C, Ellenberger C, Mattos RC, Aupperle H, Dhein S, Stief B, Schoon HA.This paper describes the histomorphological and immunohistochemical characterisation of phenotypic variations of endometrosis as well as potential etiological factors which may influence disease progression. In total, 779 endometrial biopsies were examined. These biopsies were taken in the breeding and non-breeding season (n=509), on defined days during the estrous cycle (n=70) and before and after experimentally induced bacterial endometritis (n=200). In addition to conventional histopathology, selected biopsies were investigated using alcianblue staining as well as immunohistochemical method...
Yuan ZQ, Gault EA, Gobeil P, Nixon C, Campo MS, Nasir L.It is now widely recognized that BPV-1 and less commonly BPV-2 are the causative agents of equine sarcoids. Here we present the generation of equine cell lines harboring BPV-1 genomes and expressing viral genes. These lines have been either explanted from sarcoid biopsies or generated in vitro by transfection of primary fibroblasts with BPV-1 DNA. Previously detected BPV-1 genome variations in equine sarcoids are also found in sarcoid cell lines, and only variant BPV-1 genomes can transform equine cells. These equine cell lines are morphologically transformed, proliferate faster than parental ...
Williams KJ, Maes R, Del Piero F, Lim A, Wise A, Bolin DC, Caswell J, Jackson C, Robinson NE, Derksen F, Scott MA, Uhal BD, Li X, Youssef SA, Bolin SR.Pulmonary fibrosis and interstitial lung disease are poorly understood in horses; the causes of such conditions are rarely identified. Equine herpesvirus 5 (EHV-5) is a gamma-herpesvirus of horses that has not been associated with disease in horses. Pathologic and virologic findings from 24 horses with progressive nodular fibrotic lung disease associated with EHV-5 infection are described and compared with 23 age-matched control animals. Gross lesions consisted of multiple nodules of fibrosis throughout the lungs. Histologically, there was marked interstitial fibrosis, often with preservation ...
Derksen FJ, Williams KJ, Uhal BD, Slocombe RF, de Feijter-Rupp H, Eberhart S, Berney C, Robinson NE.Exercise-induced pulmonary haemorrhage (EIPH) occurs in the majority of horses performing strenuous exercise. Associated pulmonary lesions include alveolar and airway wall fibrosis, which may enhance the severity of EIPH. Further work is required to understand the pulmonary response to blood in the equine airways. Objective: To confirm that a single instillation of autologous blood into horse airways is associated with alveolar wall fibrosis, and to determine if blood in the airways is also associated with peribronchiolar fibrosis. Methods: Paired regions of each lung were inoculated with bloo...
Coudry V, Jean D, Desbois C, Tnibar A, Laugier C, George C.Ventricular dysrhythmias are more commonly associated with myocardial disease than are supraventricular dysrhythmias. Management of arrhythmias under general anesthesia is difficult because of the dysrhythmogenic effects of the anesthetic drugs. This report describes a severe ventricular dysrhythmia observed in a pony under general anesthesia, with a severe and old myocardial fibrosis found on postmortem examination. Fibrose du myocarde chez un cheval présentant de la tachycardie ventriculaire polymorphe observée au cours d’une anesthésie générale. Les dysrythmies ventriculaires sont pl...
Nomura M, Hosaka Y, Kasashima Y, Ueda H, Takehana K, Kuwano A, Arai K.The DNA microarray analysis for matrix metalloproteinase (MMP)-related mRNA expression in equine superficial digital flexor tendinitis indicated that mRNA level of MMP-13 was apparently up-regulated in the tendinitis as compared to normal tendon. In situ hybridization also revealed that fibroblastic cells proliferated in the granulation tissue generated in the tendinitis actively expressed MMP-13 mRNA. On the other hand, in normal tendon, a few fibroblastic cells and vascular components lied in the endotenon barely expressed its mRNA, but other cellular components in the tendon bundle were not...
Ortega J, Daft B, Assis RA, Kinde H, Anthenill L, Odani J, Uzal FA.Omphalitis and the resulting septicemia contribute to perinatal mortality in several animal species. In foals, the most important causes of omphalitis are Escherichia coli and Streptococcus zooepidemicus. However to date, no information has been published about the role of Clostridium sordellii in these infections. In this paper, we describe 8 cases of perinatal mortality in foals associated with internal umbilical remnant infection by C. sordellii. The foals studied were between 12 and 21 days old at the time of death, and various breeds were represented in the group. Five of the foals were m...
Brown DL, Anderson M, Cullen JM.Mesenchymal hamartoma of the liver is a rare congenital disorder of biliary tract development. During the necropsy of a late-term equine fetus, a markedly enlarged liver of more than two times normal weight was found. Light microscopic review revealed that the normal hepatic parenchyma had been obliterated, replaced, and expanded by abnormal bile ducts surrounded by abundant, myxoid stroma. The lesion was diagnosed as a mesenchymal hamartoma. Small portions of the liver had bridging septa of fibrosis and proliferations of small-caliber abnormal bile ducts, resembling another congenital biliary...
Staszyk C, Gasse H.Fibroblasts and cementoblasts in the periodontal ligament (PDL) of equine cheek teeth were harvested, and monocultures were obtained by means of a "selective detachment" procedure. Cells were characterized by morphological criteria and by immunostaining for vimentin, FVIII, pan-cytokeratin, smooth muscle actin, and pro-collagen. Cementogenic potential of the cells was determined by immunostaining for osteopontin and by histochemical detection of alkaline phosphatase. Equine periodontal fibroblasts (EPF) were spindle-shaped and polygonal. Equine dental cementoblasts (EDC) grew in cobblestone-li...
Waitt LH, Cebra CK, Tornquist SJ, Löhr CV.A 22-year-old pinto mixed breed mare was admitted for evaluation of severe colic signs and gastric reflux. Multiple nonpainful, variably sized hard masses were palpated in the subcutis over the thorax, abdomen, and hindquarters of the horse. The mare was diagnosed with sterile peritonitis and had systemically high gamma-glutamyltransferase, amylase, and lipase. Three days into treatment she became febrile with signs of persistent and mild abdominal discomfort; euthanasia was elected. Necropsy revealed peripancreatitis, pancreatic fibrosis, abdominal steatitis and panniculitis. Panniculitis ass...
Young AE, Bower LP, Affolter VK, De Cock HE, Ferraro GL, Bannasch DL.Chronic progressive lymphedema (CPL) is a debilitating condition identified in Clydesdales, Shires and Belgian draft horses and results in progressive swelling of the lower legs associated with the development of thick skin folds, ulcerations, fibrosis and marked hyperkeratosis. The result is severe discomfort and recurrent secondary infection, often requiring euthanasia. Due to the delayed onset, many horses are bred prior to diagnosis. CPL has only been documented in three related draft horse breeds, suggesting a genetic cause. Determining the molecular basis would enable owners to test hors...
Dubuc V, Lepault E, Theoret CL.Wound repair in horse limbs is often complicated by excessive fibroplasia and scarring. Occlusion of the microvessels populating the granulation tissue appears to be involved in the excessive accumulation of extracellular matrix during the repair of limb wounds. This study aimed to determine whether endothelial cell hypertrophy or hyperplasia, or both, contribute to microvascular occlusion and whether the pericyte is involved in this anomaly. We created 5 wounds, each 2.5 x 2.5 cm, on both forelimbs and on the body of 6 horses. One limb was bandaged to stimulate excessive wound fibroplasia. We...
Epstein KL, Parente EJ.To report a laparoscopic technique for insertion of polypropylene mesh in the nephrosplenic space in horses and evaluate outcome. Methods: Descriptive experimental study. Methods: Five healthy mature horses. Methods: One laparoscope and 2 instrument portals were made on the left side of the horse. The nephrosplenic space was measured and appropriately sized polypropylene mesh was inserted and attached to the dorsolateral splenic capsule and perirenal fascia using helical titanium coils. All horses had repeat laparoscopy 4 weeks later and were necropsied at intervals 4-14 weeks after mesh place...
Story MR, Gaughan EM, Andrews GA, Balch S.A 14-month-old male Quarter horse was presented for evaluation of a grade 3 out of 5 (grade 0 = sound; grade 5 = non-weight bearing) right rear lameness. A firm, 8 x 16 cm mass was palpable at the caudal medial aspect of the distal tibia and proximal tarsal region of the right hind limb. A percutaneous needle aspirate contained mesenchymal cells that were moderate to large in size with single, oblong nuclei. Differential diagnoses included fibrous hyperplasia, fibroma, or well-differentiated fibrosarcoma. Excisional biopsy for both definitive diagnosis and treatment was offered and selected by...
Singh K, Holbrook TC, Gilliam LL, Cruz RJ, Duffy J, Confer AW.Multisystemic eosinophilic epitheliotropic disease was diagnosed histologically in a 17-year-old Quarter Horse intact mare that was presented with a chronic history of respiratory distress. At necropsy, the lungs were poorly collapsed and the pulmonary parenchyma contained innumerable, discrete, spherical nodules in a miliary pattern. A few similar nodules were scattered in the liver and the renal lymph nodes. Histologically, these nodules consisted of fibrosing eosinophilic granulomas. Based on histologic findings and the absence of an etiologic agent, a diagnosis of multisystemic eosinophili...
Matsuda K, Tabata S, Kawamura Y, Kurosawa T, Yoshie N, Taniyama H.Ectopic bone formation in the left atrioventricular valves and cardiac fibroskeleton, with systemic circulatory disturbance, is reported in a 4-year-old crossbred heavy horse. Microscopically, there was fibrosis, chondral metaplasia and mature bone, with bone marrow within the left atrioventricular cusps and in the annuli of the aortic and right atrioventricular valves.
Walthall JC, McKenzie RA.Horses grazing manily Cenchrus ciliaris and/or Panicum maximum var. trichoglume pastures on over 30 properties in southern central Queensland developed lesions of osteodystrophia fibrosa. Horses on individual properties in coastal Queensland grazing Setaria anceps, Brachiaria mutica or Pennisetum clandestinum also developed the disease. Ill-thrift, lameness, and fibrous swellings of nasal bones, maxillae and mandibles were observed. Calcium and phosphorus levels of pasture were normal but all the above pasture species contained oxalates which were suspected of causing the disease.
Molín J, Asín J, Vitoria A, Sanz A, Gimeno M, Romero A, Sánchez J, Pinczowski P, Vázquez FJ, Rodellar C, Luján L.A 1-month-old Purebred Spanish Horse (PSH) foal presented with progressive hepatic failure culminating in death. Hepatic lesions were consistent with congenital hepatic fibrosis (CHF). Genetic studies in the PKHD1 gene in the affected foal revealed that it was heterozygous for the 2 previously described single-nucleotide polymorphisms (SNPs) linked to CHF in Swiss Franches-Montagnes (SFM) horses. In addition, 2 novel mutations were detected, the foal being homozygous for one of them and heterozygous for the other. Genetic studies in a healthy PSH population ( n = 35) showed a 3-fold higher gen...
Knight AP, Kimberling CV, Stermitz FR, Roby MR.The death of 10 horses was attributed to feeding dried grass hay containing hound's-tongue, Cynoglossum officinale. Affected horses developed weight loss, icterus, photosensitization, and hepatic encephalopathy. Histologic examination of the liver of 3 of the horses revealed megalocytosis, biliary hyperplasia, and fibrosis characteristic of pyrrolizidine alkaloid poisoning. Hound's-tongue was found to contain large quantities (0.6% to 2.1%, dry matter basis) of toxic pyrrolizidine alkaloids, which, when fed to a pony for 20 days, caused liver fibrosis and biliary hyperplasia.
Buergelt CD, Greiner EC.Fibrosing granulomas were found in the liver and occasionally on the intestinal and diaphragmatic serosae and in the lung of 11 horses submitted for necropsy. Although these granulomas were considered incidental findings in most of the horses, they had caused liver failure in 1 horse. The granulomas typically were characterized by a dense collagenous core that frequently was mineralized. The periphery contained a rim of inflammatory cells. Only in 1 of the 11 horses was there evidence of an egg shell suggestive of schistosomes. Schistosomal eggs were not detected in the feces of the horses. Th...
Furuoka H, Shirakawa T, Taniyama H, Ohishi H, Satoh H, Itakura C.Pancreatic tissue from 20 horses was examined using immunocytochemical techniques. In aged horses, neogenesis of endocrine cells, neoformation, and hyperplasia of islets occurred closely associated with the pancreatic duct; these changes were regarded as nesidioblastosis. In addition, pancreatic fibrosis accompanied by ductal proliferation and endocrine neogenesis was considered a regenerative change. Thus, the origin of neoformation in the endocrine pancreas was in the ductal system, and it is suggested that the pancreatic endocrine cells were of endodermal origin.
Morgan SJ, Van Houten DS.Cells found in the intima and media of the cranial mesenteric artery of a mature mare with chronic arteritis were identified as smooth muscle cells and occurred in association with collagen and elastin fibres. As no fibroblasts were demonstrable within these regions, the smooth muscle cells were the likely source of the extracellular matrix. In contrast, the abnormal adventitis from the same artery contained abundant fibroblasts which are considered to be the source of the adventitial collagen.
Dean PW, Robertson JT.Seven horses were used to compare the Gambee, the crushing, and a 2-layer inverting suture pattern composed of a simple continuous layer in the mucosa oversewn with a continuous Lembert pattern in the seromuscular layer. Horses were evaluated at 30 days for adhesion formation, lumen diameter, and quality of healing at the anastomotic sites. One horse was euthanatized 9 days after surgery after 24 hours of ileus and colic; necropsy revealed septic peritonitis and widespread adhesions. One horse had no adhesions. The remaining horses had adhesions associated with 50% of the Gambee and 50% of the...
Ferreira-Dias G, Nequin LG, King SS.Pathologic changes in the endometrium of mares may be rated according to Kenney's method of classification. Category I endometrium contains healthy tissue with no or few widely scattered pathologic changes. At the opposite end, severe widespread pathologic changes are associated with category III. Uterine biopsy specimens were collected aseptically from 16 mares during the estrous and diestrous stages of the cycle. Pathologic changes were evaluated, using light microscopy, and endometrium was classified as Kenney's category I, II, or III. Endometrial tissue of category I (n = 5 mares in estrus...
Pessoa CR, Pessoa AF, Maia LA, Medeiros RM, Colegate SM, Barros SS, Soares MP, Borges AS, Riet-Correa F.The effects and susceptibility of donkeys to Crotalaria juncea and Crotalaria retusa poisoning were determined at high and low doses. Seeds of C. juncea containing 0.074% of dehydropyrrolizidine alkaloids (DHPAs) (isohemijunceines 0.05%, trichodesmine 0.016%, and junceine 0.008%) were administered to three donkeys at 0.3, 0.6 and 1 g/kg body weight (g/kg) daily for 365 days. No clinical signs were observed and, on liver and lung biopsies, the only lesion was a mild liver megalocytosis in the donkeys ingesting 0.6 and 1 g/kg/day. Two other donkeys that received daily doses of 3 and 5 g seed/...
Schwarz B, Klang A, Bezdekova B, Sárdi S, Kutasi O, Hoven R.Equine multinodular pulmonary fibrosis (EMPF), a progressive fibrosing interstitial lung disease has been associated with gammaherpesviruses. This case series describes five horses with EMPF. Three of the horses (two in Hungary, one in the Czech Republic) were diagnosed with EMPF ante mortem. They presented with typical clinical signs of EMPF including dyspnoea and weight loss. Arterial blood gas analysis revealed hypoxaemia. Blood work showed signs of inflammation like neutrophilia and hyperfibrinogenaemia. An endoscopic examination of the respiratory tract including cytology and culture of t...
Ferreira-Dias GM, Serrão PM, Durão JF, Silva JR.To document uterine growth and microvascular development in the endometrium of uteri with differing degrees of fibrosis as well as uterine growth throughout the estrous cycle of mares. Methods: 30 mares. Methods: Uterine tissue was obtained during the breeding season from a slaughter facility. Stage of estrous cycle of the mares was assessed on the basis of ovarian structures and plasma progesterone concentrations. Endometrium was characterized by use of light microscopy, and blood vessel walls were marked by histochemical techniques. Microvascular development was evaluated by a computerized i...
Straticò P, Guerri G, Palozzo A, Di Francesco P, Vignoli M, Varasano V, Petrizzi L.Capsulitis leads to the release of inflammatory mediators in the joint, causing capsular fibrosis and osteoarthritis (OA). Strain elastosonography (SE) measures the elasticity of tissue by evaluating its strain in operator-dependent deformation. The aims of the study were to assess the feasibility, repeatability, and reproducibility of SE for imaging the distal attachment of the joint capsule (DJC) of metacarpophalangeal joints in sound horses (Group S) and in horses with metacarpophalangeal OA (Group P) and to evaluate differences in the elastosonographic patterns of these horses. After a who...
Cranley JJ, McCullagh KG.The hearts and aortas of 2076 unselected horses of all ages were examined immediately after slaughter. Focal zones of fibrosis, observed in the myocardium of 14.3 per cent of hearts examined, were found in both atria and ventricles and were unrelated to age. Microscopically the majority of lesions involved myocardial fibre lysis and replacement fibrosis, although acute infarction was present in some cases. Intramyocardial arterioles in or adjacent to the lesions exhibited occlusive arteriosclerotic changes whereas those elsewhere remained patent. The evidence strongly suggests that the myocard...
Giannitti F, Petrov R, Parker J, Booth M, Anderson M.A 9-year-old Thoroughbred gelding presented with a 97-day history of poor performance and intermittent fever. Clinicopathologic changes included increased serum activity of γ-glutamyltransferase and alkaline phosphatase, mild hyperbilirubinemia, and leukocytosis with neutrophilia and lymphopenia. Abdominal ultrasound revealed hepatomegaly with hyperechoic hepatic parenchyma and biliary distention. Pathologic findings included marked hepatomegaly (liver 3.6% of body weight), firm hepatic consistency with a diffuse enhanced reticular pattern, severe portal bridging and sinusoidal fibrosis, oval...
Nixon AJ, Stashak TS, Smith FW, Norrdin RW.Carbon fibre-polylactic acid composites and monofilament non-absorbable suture material were compared for the repair of surgically transected superficial digital flexor tendons in 10 horses. All surgical wounds healed by first intention. The repaired tendons were enlarged, the carbon implanted tendons being larger than those sutured. The horses were killed at six, eight, 12,20 or 24 weeks. Greater fibrous thickening occurred in tendons repaired with carbon fibre, especially at 12 weeks postoperatively. Carbon fibre incited a greater histological response with macrophages, lymphocytes, plasma c...
Amaral A, Fernandes C, Szóstek-Mioduchowska A, Lukasik K, Rebordão MR, Pinto-Bravo P, Skarzynski DJ, Ferreira-Dias G.Cathepsin G (CAT) is a protease released by neutrophils when forming neutrophil extracellular traps that was already associated with inducing type I collagen (COL1) in equine endometrium in vitro. Endometrosis is a fibrotic condition mainly characterized by COL1 deposition in the equine endometrium. The objective was to evaluate if noscapine (an alkaloid for cough treatment with anti-neoplastic and anti-fibrotic properties) would reduce transcription (evaluated by qPCR) and COL1 protein relative abundance (evaluated by western blot) induced by CAT in equine endometrial explants from follicula...
Easton-Jones CA, Madigan JE, Barnum S, Maxwell LK, Taylor SD, Arnesen T, Pusterla N.Equine herpesvirus-5 is commonly isolated from the lungs of horses with EMPF, suggesting an etiological link. Valacyclovir is used empirically to treat EMPF; however, no data is available concerning its impact on EHV-5 viral kinetics. Objective: To determine the effect of oral administration of valacyclovir on EHV-5 viral load measured by qPCR in blood, nasal secretions (NS) and BALF in horses with EMPF. Methods: Six horses diagnosed with EMPF. Methods: A prospective clinical trial was performed. Horses received 10 days of PO administered valacyclovir (loading dose 30 mg/kg, maintenance dose 2...
Janicek J, Lopes MA, Wilson DA, Reed S, Keegan KG.Fibrotic myopathy can cause incapacitating gait abnormalities. Transection of the fibrotic mass followed by early post operative exercise is the best treatment for fibrotic myopathy. A laser may be used to transect the fibrotic mass. Assessment of the effectiveness of therapies for fibrotic myopathy has been limited to subjective evaluation. Objective: To objectively assess gait abnormalities associated with fibrotic myopathy before and after laser fibrotomy followed by early post operative exercise. Methods: Kinematic evaluation of horses with fibrotic myopathy walking and trotting on a tread...
Silva GTA, Guest BB, Gomez DE, McGregor M, Viel L, O'Sullivan ML, Runciman J, Arroyo LG.Calcification of the tunica media of the axial pulmonary arteries (PA) has been reported in a large proportion of racehorses. In humans, medial calcification is a significant cause of arterial stiffening and is implicated in the pathogenesis of cardiac, cerebral, and renal microvascular diseases. Pulse wave velocity (PWV) provides a measure of arterial stiffness. This study aimed to develop a technique to determine PA-PWV in horses and, secondarily, to investigate a potential association between PA-PWV and arterial fibro-calcification. A dual-pressure sensor catheter (PSC) was placed in the ma...
Elemmawy YM, Senna NA, Abu-Seida AM, Youssef AF.Injury of suspensory ligament (SL) branch is a frequently diagnosed problem in horses of different ages and disciplines. This case reports for the first time the ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI) findings in a 10-year-old draught horse with traumatic chronic SL branch desmitis of 8 months duration. The horse had a grade 3 of 5 left hindlimb lameness with a moderately hot, painful, and diffuse swelling from the tarsus till the hoof. Ultrasonography, both SL branches appeared as enlarged hyperechogenic structures with poor demarcation of their margins a...
Tulleners E, Mann P, Raker CW.Epiglottic augmentation with injectable bovine collagen or an autogenous or allogenous auricular cartilage graft was performed in 12 horses with endoscopically and radiographically normal epiglottises. The grafting procedures were easy to perform and did not cause apparent discomfort. Cartilage graft extrusion or resorption may have occurred, but was not seen by endoscopy and lateral laryngeal radiography. Only collagen implants remained evident endoscopically, as smooth round submucosal bulges ventral to the epiglottic cartilage. Two horses with collagen implants, and all horses with cartilag...
Souza SS, Aguiar FLN, Alves BG, Alves KA, Brandão FAS, Brito DCC, Raposo RDS, Gastal MO, Rodrigues APR, Figueiredo JR, Teixeira DÍA, Gastal EL.Ovarian tissue transplantation methods using cooled and cryopreserved samples have been attractive options for fertility preservation in animal models and humans. The aim of this study was to evaluate the impact of previous exposure to cooling, cryopreservation, and VEGF on the overall efficiency of equine ovarian tissue after heterotopic xenotransplantation in mice. The end points evaluated were follicular morphology and development, follicular and stromal cell densities, angiogenesis (i.e. the density of new and mature blood vessels), collagen types I and III fiber densities, and total fibro...
Neto da Silva AC, Costa AL, Teixeira A, Alpoim-Moreira J, Fernandes C, Fradinho MJ, Rebordão MR, Silva E, Ferreira da Silva J, Bliebernicht M....In older mares, increasing collagen fibers (fibrosis) in the endometrium and oviduct predisposes to sub-fertility and infertility. In this study, (i) gene transcription of collagen (qPCR: COL1A1, COL1A2, COL3A1, COL5A1); (ii) total collagen protein (hydroxyproline); (iii) collagen distribution (Picrosirius red staining; polarized light microscopy); and (iv) microvascular density (Periodic acid-Schiff staining), were evaluated in mares' placenta, and related to mares age, and placenta and neonate weights. Samples were collected from the gravid horn, non-gravid horn, and body of the placenta fro...
Rijkenhuizen AB, Németh F, Dik KJ, Goedegebuure SA.A macroscopical, arteriographical and histological study was made of the arterial supply of the navicular bones of horses with clinical and/or radiographic signs of navicular disease. Based on the clinical and radiological findings the navicular bones of 40 Warmblood horses are divided into four different groups. In the pattern of the arteriogram obvious changes are noticed: an imbalance and a distal to proximal shift between the distal and proximal arterial supply occur, indicating a reduction of the distal blood supply with a compensatory reaction of the proximal, medial and lateral supply. ...
Valentine BA, Del Piero F, Edwards RB.Intramuscular desmoid tumors (musculoaponeurotic fibromatosis) were discovered in two young adult horses. The tumor in one horse was in the lateral cervical musculature, and that in the second horse occurred in the pectoral musculature. Histopathologic features were similar in both horses and included proliferation of fibroblasts and cells expressing muscle actin (myofibroblasts), with extensive dissecting fibrosis within muscle. These features are similar to those of desmoid tumors in humans, particularly those also known as musculoaponeurotic fibromatosis. Dissection of these lesions reveale...
Schmidbauer SM, Venner M, von Samson-Himmelstjerna G, Drommer W, Gruber AD.Interstitial lung disease with chronic fibrosis is a frequent cause of reduced performance in horses. The aim of this study was to establish a model of acute alveolar damage and interstitial lung disease in horses that could be used to monitor the histopathological lesions and changes in expression levels of genes relevant to pulmonary fibrosis. Six adult horses were given a single intravenous injection (6 mg per kg body weight) of perilla mint ketone (PMK). Transthoracic lung biopsy samples (1 x 0.2 x 0.2 cm) were collected before and after (days 1, 4, 8, 11, 15, 18, 22, 25 and 29) the admini...
Berry CR, O'Brien TR, Madigan JE, Hager DA.Clinical records and thoracic radiographs of 19 horses with a confirmed pathologic diagnosis of silicosis were reviewed. These horses had histories of varying degrees of chronic weight loss, exercise intolerance, and respiratory distress. At the time of presentation, two horses were asymptomatic. Ten horses were geldings and nine were female. The mean age of the 19 horses was 10.7 +/- 5.5 years. Fourteen horses were identified as being from the Monterey-Carmel Peninsula of midcoastal California. An abnormal, structured interstitial pulmonary pattern was identified on thoracic radiographs in ea...
Epstein KL, Parente EJ.To report a laparoscopic technique for insertion of polypropylene mesh in the nephrosplenic space in horses and evaluate outcome. Methods: Descriptive experimental study. Methods: Five healthy mature horses. Methods: One laparoscope and 2 instrument portals were made on the left side of the horse. The nephrosplenic space was measured and appropriately sized polypropylene mesh was inserted and attached to the dorsolateral splenic capsule and perirenal fascia using helical titanium coils. All horses had repeat laparoscopy 4 weeks later and were necropsied at intervals 4-14 weeks after mesh place...
Aristizabal FA, Lopes MA, Silva A, Avanza MF, Nieto JE.To evaluate the effect of onlay mesenteric flaps (MFs) with end-to-end jejunojejunostomy on stomal diameter, length of jejunum with reduced stomal diameter, abdominal adhesion formation, and healing. Methods: Experimental study. Methods: Healthy adult horses (n = 6). Methods: Two hand sewn end-to-end jejunal anastomoses using a 1 layer simple continuous serosubmucosal suture pattern were performed in each horse ∼ 2 and 5 m oral to the ileocecal fold. Using a random design for selection anastomosis location (oral or aboral), 1 anastomosis was covered with 2 adjacent onlay MFs secured with int...
