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Topic:Biopsy
Biopsy in horses involves the collection of tissue samples for diagnostic purposes, often to identify the presence of disease, evaluate tissue abnormalities, or monitor treatment responses. This procedure can be performed on various tissues, including skin, muscle, liver, and other organs, depending on the clinical indications. Biopsies are typically obtained using specialized instruments and techniques to ensure minimal discomfort and accurate sample collection. The analysis of biopsy samples can provide detailed histological information that aids in diagnosing conditions such as neoplasia, inflammatory diseases, and infectious processes. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and outcomes of biopsy procedures in equine veterinary practice.
Lawsonia intracellularis-like organism infection in a miniature foal. A 7-month-old foal was admitted to the hospital with a history of lethargy, weight loss, mild diarrhea, and anorexia. A diagnosis of proliferative enteritis caused by Lawsonia intracellularis-like organisms was made after necropsy and histologic examination of the small intestine. Although infection with L intracellularis-like organisms is a rare cause of enteritis in foals, it should be considered in the differential diagnosis, especially if the foal was housed in the proximity of pigs or pig feces. Antemortem diagnosis remains challenging because isolation of the organism in fecal material r...
Histopathological findings in equine sinonasal disorders. Biopsies collected from 79 referred cases of equine sinonasal disease, including 27 horses with primary sinusitis, 10 with secondary dental sinusitis, 19 with sinus cysts, 11 with progressive ethmoid haematomata (PEH), 4 with false nostril epidermal inclusion cysts, 4 with sinonasal polyps, 3 with sinonasal mycosis and from 2 control animals were examined histologically. Observations were made on epithelial type and integrity, cellular inflammatory response, fibroplasia and presence of potential pathogens. Chronic inflammatory changes including mucosal thickening, ulceration and significant fi...
Hemothorax in 2 horses. This report documents the successful conservative medical management of hemothorax in 2 horses. Hemothorax occurred after a lung biopsy procedure (horse 1) and strenuous exercise on a treadmill (horse 2). The horses had tachypnea, tachycardia, nostril flaring, hemoptysis, and pawing. Hemothorax was suspected based upon absence of auscultable ventral lung sounds; development of cool extremities and pale, tacky mucous membranes; the ultrasonographic appearance of moderate to severe amounts of pleural fluid; and a concurrent decrease in hematocrit and total plasma protein. Both horses were treate...
A comparison of the ultrastructure and metabolic response of the skeletal muscle of horses performing intense treadmill exercise at 20 and 35 degrees C. The aim of this study was to determine whether the metabolic response and ultrastructure of muscle differed when horses performed intense exercise at different ambient temperatures. Four Standardbred geldings performed treadmill exercise, including an intensive trot of 2600 m on two different occasions, either at a high ambient temperature of 35 degrees C or at a temperature of 20 degrees C. The horses had a warm-up period of 23.5 min of submaximal exercise, followed by 2 h of box rest before the intensive exercise. Muscle biopsy data of adenine nucleotides, creatine phosphate, lactate and gly...
Distribution of fast myosin heavy chain-based muscle fibres in the gluteus medius of untrained horses: mismatch between antigenic and ATPase determinants. The distribution of muscle fibres classified on the basis of their content of different myosin heavy chain (MHC) isoforms was analysed in muscle biopsies from the gluteus medius of adult untrained horses by correlating immunohistochemistry with specific anti-MHC monoclonal antibodies and standard myofibrillar ATPase (mATPase) histochemistry. Percutaneous needle biopsies were taken at 3 depths (20, 40 and 60 mm) from 4 4-y-old Andalusian stallions. The percentage of 'pure' I MHC fibres increased whereas that for pure IIX MHC fibres decreased from the most superficial to the deepest sampling sit...
Factors controlling epidermal growth factor (EGF) gene expression in the endometrium of the mare. Previous studies showed a dramatic increase in EGF gene expression in the endometrial glands of pregnant mares around day 40 after ovulation. To investigate how the steroid hormones of pregnancy might regulate this expression, in situ hybridization was used to monitor the levels of EGF mRNA in endometrial biopsies obtained from seasonally anoestrous or ovariectomised mares given exogenous progesterone and oestrogen, alone or in combination, for up to 46 days. Biopsies were also taken from mares during the non-pregnant cycle, during normal pregnancies and pregnancies compromised by endometrial ...
Oxytocin-neurophysin I mRNA abundance in equine uterine endometrium. A positive-feedback loop between luteal oxytocin and uterine prostaglandin F2 alpha (PGF) is a major signal for luteolysis in ruminants. Likewise, uterine PGF causes luteolysis in mares, but the involvement of oxytocin in this process is unclear. We wanted: 1) to determine if the oxytocin-neurophysin I (OT-NP I) gene is transcribed into mRNA in the endometrium of mares; and, if so, 2) to analyze relative changes in abundance of endometrial OT-NP I mRNA throughout the estrous cycle and during early stages of pregnancy. Endometrial biopsies were obtained from nonbred mares during estrus, and 5, ...
Effect of ischemia and reperfusion on neutrophil accumulation in equine microvascular tissue flaps. 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...
An immunohistochemical study of interstitial cells of Cajal (ICC) in the equine gastrointestinal tract. The interstitial cells of Cajal (ICC) are c-kit immunoreactive cells of the gastrointestinal tract which are suggested to have a role in the control of intestinal motility. Cells with c-kit immunoreactivity have not been previously described in the gastrointestinal tract of the horse. Immunoreactivity for c-kit was revealed using immunohistochemical labelling with an anti-c-kit polyclonal antibody. Sections of normal gastrointestinal tissue were examined from 13 anatomically defined sites from stomach to small colon taken from horses free from gastrointestinal disease. Three types of c-kit imm...
Spinal muscle pathology. Clinical signs that are easily referred to spinal muscle pathology include atrophy of epaxial muscles, focal swelling and palpable tenderness, as well as enlarged muscles with increased tone. Less easily recognized signs include rigidity of the spine, shortened stride, hindlimb lameness, and indicators of poor performance. Muscle biopsy is one option in evaluating sore backs and is best used when physical examination and imaging procedures do not reveal a likely diagnosis or when conventional treatments are unsuccessful. Rhabdomyolysis of spinal muscles may be due to nutritional myodegeneratio...
Oral metastasis of renal cell carcinoma in a horse. A 14-year-old hunter gelding presented with an ulcerated mass on the left premaxilla. Biopsy of the mass revealed a poorly differentiated carcinoma. Surgical excision was attempted, but local regrowth followed several months later, at which point radiotherapy was carried out. An initial improvement was followed by marked deterioration and the animal was humanely killed. Post-mortem examination revealed a massively enlarged right kidney and associated widespread metastases. A metastatic clear cell renal carcinoma was identified by histological examination.
Unique localization of protein gene product 9.5 in type B synoviocytes in the joints of the horse. Fibroblast-like (Type B) synoviocytes are cells in the synovial membrane that are responsible for production of both synovial fluid and the extracellular matrix in the synovial intima. Immunostaining of the horse synovial membrane for protein gene product (PGP) 9.5, which is a neuron-specific ubiquitin C-terminal hydrolase, demonstrated selective localization of the immunoreactivity in a synoviocyte population different from acid phosphatase-positive Type A synoviocytes. The immunoreactive cells were lined up in the synovial intima and extended dendritic processes towards the joint cavity to f...
Studies on equine lipid metabolism. 1. A fluorometric method for the measurement of lipolytic activity in isolated adipocytes of rats and horses. A simple and sensitive method for direct and continuous monitoring of free fatty acid (FFA) release, by measuring the pH-sensitive change in relative fluorescence intensity of seminaphthofluorescein (SNAFL-1) is described. The method was designed to use a small number of adipocytes isolated from fat pads of rats and biopsy specimens of horses for the detection of decreasing pH in fat cell suspensions caused by released FFA into the incubation medium. Species specific differences of lipolysis were demonstrated when adipocytes of rats and horses are incubated with stimulators or inhibitors of li...
Successful treatment of an equine preputial fibrosarcoma using 5-fluorouracil/evaluation of the treatment using quantitative PCNA and Ki67 (MIB 1) immunostaining. (case report). An 18-month-old cross-bred Fjord pony colt presenting a fibrosarcoma of the prepuce with severe infiltrative growth, was treated by topical application of 5-fluorouracil. Biopsies were taken before and after a treatment period of 2 months. As a control, preputial tissue from a healthy horse was biopsied. Tissue sections were stained immunohistochemically for Proliferating Cell Nuclear Antigen (PCNA) and Proliferation related factor--Ki67 (MIB1). Using computerized quantitative image analysis of these sections, Mitotic index (PCNA), Growth Fraction (Ki67) and total nuclear area percentage of th...
Morphologic comparisons among equine endometrium categories I, II, and III, using light and transmission electron microscopy. To evaluate whether the pathologic changes observed by light microscopy in endometrium of categories II and III were reflected by cellular changes and to describe differences in the endometrial cell ultrastructure during estrus and diestrus. Methods: 18 healthy mares. Methods: Endometrial tissues biopsied during the physiologic breeding season were categorized, using light microscopy, and were studied, using transmission electron microscopy (TEM). Results: Using TEM, glycogen granules were associated with giant mitochondria for all endometrial types during diestrus. Development of rough endopl...
Lymphoproliferative and myeloproliferative disorders. Nomenclature regarding neoplasia of the hematopoietic and lymphoid tissues in the horse is confusing. This article will clarify terminology, and discuss the individual lymphoproliferative and myeloproliferative disorders recognized in the horse. Diagnostic techniques that are useful in cases in which hematopoietic or lymphoid tissue neoplasia are suspected include histochemical staining profiles, bone marrow aspiration, and bone marrow biopsy.
Survey of the large animal diplomates of the American College of Veterinary Internal Medicine regarding percutaneous lung biopsy in the horse. A survey designed to obtain information on the indications, contraindications, complications, and methodology of percutaneous lung biopsy in the horse was sent to large animal diplomates of the American College of Veterinary Internal Medicine. Sixty-five of 190 diplomates returned the survey (response rate: 34%) and 59 of these 65 respondents (91%) indicated that they worked with horses. Forty-four diplomates had performed a percutaneous lung biopsy in 1 or more horses (i.e. 75% of those diplomates working with horses and 68% of total respondents). Clinical and radiologic diagnoses that prompt...
Muscle anaerobic response to a maximal treadmill exercise test in Standardbred trotters. The purpose of this study was to develop a standardised maximal treadmill exercise test performed until fatigue in order to find reproducible markers for anaerobic metabolism, specifically adenine nucleotide degradation. Six Standardbred trotters performed an incremental maximal treadmill exercise test in 1 min steps (starting with 7 m/s) until they could no longer keep pace with the treadmill. The test was performed twice with at least one week between the tests. Heart rate was recorded and venous blood samples were obtained during the test and in the recovery period for determination of plas...
Occult osseous metastasis of a colonic adenocarcinoma visualized with technetium tc 99m hydroxymethylene diphosphate scintigraphy in a horse. A 5-year-old Arabian horse was admitted with a 5-day history of undulant pyrexia of unknown origin, inappetence, obtundation, and acute collapse. Physical examination results were unremarkable except for a grade II/VI left-sided systolic cardiac murmur and abdominal splinting. Mild chronic inflammatory changes were evident on clinicopathologic evaluation. Echocardiography revealed moderate aortic insufficiency. A solitary soft tissue opacity was found on thoracic radiography but not on ultrasonography. Palliative treatment was ineffective. Nuclear scintigraphy with WBC labeled with technetium ...
Morphometric analysis of endometrial periglandular fibrosis in mares. To develop an objective, quantifiable assay for endometrial periglandular fibrosis (EPF) and correlate assay results with histologic and ultrastructural changes in equine endometrial biopsy specimens. Methods: Endometrial biopsy specimens from 70 mares from 3 to 27 years old in estrus. Methods: In a double-blinded study design, endometrial biopsy specimens were graded histologically (modified Kenney classification) for EPF and inflammation. Endometrial periglandular collagen volume fraction (%EPCVF) was determined by light microscopic image analysis of picrosirius red-stained sections. Specime...
Paraneoplastic pruritus and alopecia in a horse with diffuse lymphoma. An 8-year-old castrated male Paint Horse was referred because of generalized pruritus, alopecia, and intermittent fever. Results of gross evaluation of the skin and microscopic evaluation of skin scrapings were inconclusive. Histologic examination of skin biopsy specimens revealed vasculitis. The horse had persistent hypercalcemia; therefore, lymphosarcoma was considered a possibility. Ultrasonography revealed hypoechoic nodules within the parenchyma of the spleen and liver. Results of microscopic evaluation of an aspirate from a splenic nodule were suggestive of lymphosarcoma. The condition o...
Occurrence and importance of glomus organs (Hoyer-Grosser’s organs) in the skin of the equine and bovine mammary gland. Glomus organs (Hoyer-Grosser's organs) were frequently found in the corium and the subcutis of the skin of the equine and bovine mammary gland. They were most frequently situated in the border zone between the stratum profundum and the stratum superficiale corii. These specialized vascular structures (arterio-venous anastomosis) were present in all investigated skin areas. Although the glomus organs varied in size and shape, they possessed common histologic structures: an arteriole entered the connective capsule of the glomus and divided into strongly convoluted arterio-venous channels; the ar...
Skeletal muscle glycolytic capacity and phosphofructokinase regulation in horses with polysaccharide storage myopathy. To determine whether polysaccharide storage myopathy (PSSM) in Quarter Horses is attributable to a defect in glycolysis or in the allosteric regulation of phosphofructokinase (PFK) enzyme. Methods: Muscle biopsy specimens were obtained from 6 Quarter Horses with PSSM and 8 Quarter Horse or Thoroughbred control horses. Methods: Maximal activity of glycogenolytic and glycolytic enzymes was determined spectrophotometrically. Maximal activity of PFK was determined for each horse at pH 8.0, and at pH 7.0 when variable concentrations of the activators, fructose 6 phosphate, fructose 2,6 bisphosphate...
Ultrasound-assisted diagnosis of renal dysplasia in a 3-month-old Quarter Horse colt. A 3-month-old foal was presented for correction of bilateral angular limb deformities. Azotemia was detected as an incidental finding. Small, misshapened, hyperechoic kidneys with decreased corticomedullary demarcation were noted with ultrasonography. Additionally, the internal renal architecture was abnormal in that the intrarenal vessels and distant collecting system were not clearly seen in either kidney. Ultrasound-guided renal biopsy was suggestive of congenital renal dysplasia, which was later confirmed at necropsy. Clinical, sonographic, and pathologic features of equine renal dysplasia...
ATP loss with exercise in muscle fibres of the gluteus medius of the thoroughbred horse. Muscle ATP loss with exercise has implications both to the causes of fatigue and muscle damage. To study this at the single muscle fibre level, five trained thoroughbred horses performed consecutive 90 second gallops on an inclined treadmill followed by a final gallop to fatigue. Biopsies of the m. gluteus medius were taken at rest, post-exercise and during 24 hour recovery. Blood lactate was 20.0 mmol litre-1 or more, and plasma NH3 300-800 mumol litre-1, following the final gallop. Minimal changes occurred in the plasma markers, CK and AST. ATP loss with exercise was 32.2 (SD 12.2) per cent....
Mycosis fungoides in a horse. A 17-year-old Quarter Horse mare was examined to determine the cause of a vulvar mass. Differential diagnoses for the swollen, ulcerated tissue included hypersensitivity reaction to insect stings or bites and cutaneous neoplasia. During the next 4 months, the mass enlarged involving the skin of the perineum and ventral aspect of the abdomen with secondary dependent edema of both hind limbs. Histologic examination of biopsy and necropsy specimens revealed changes consistent with a diagnosis of mycosis fungoides (cutaneous T-cell lymphoma). Diagnostic features included invasion of neoplastic lym...
Androgen receptors and skeletal muscle composition in trotters treated with nandrolone laureate. To study the effects of nandrolone laureate (19-nortestosterone) on muscle hypertrophy and concentration of androgen receptors (AR), biopsy specimens were taken from the middle gluteal muscle of 6 Finnhorse trotters (geldings and mares) undergoing training before, immediately after, and 13 weeks after a 14-week treatment with nandrolone. Another 6 similarly trained horses served as controls. An additional 10 mares and 10 geldings were used to study annual variation in muscle concentration of AR. AR was immunohistochemically localized in the nuclei. AR concentration remained constant during the...
A sensitive electrophoretic method for the quantification of myosin heavy chain isoforms in horse skeletal muscle: histochemical and immunocytochemical verifications. In adult horses, three myosin heavy chain (MyHC) isoforms can be identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunohistochemistry using specific anti-MyHC monoclonal antibodies. This report studies the suitability of a consistent SDS-PAGE technique for quantifying MyHC profiles in homogenized cryostate sections of equine gluteus medius muscle biopsies (n = 18). The method used (previously described by R. J. Talmadge and R. R. Roy; J. Appl. Physiol. 1993, 75, 2337-2340) resolved MyHCs in three bands: I, IIB or IIX, and IIA from the fastest to the slowe...
Skeletal muscle histology and biochemistry of an elite sprinter, the African cheetah. To establish a skeletal muscle profile for elite sprinters, we obtained muscle biopsy samples from the vastus lateralis, gastrocnemius and soleus of African cheetahs (Acinonyx jubatus). Muscle ultrastructure was characterized by the fiber type composition and mitochondrial volume density of each sample. Maximum enzyme activity, myoglobin content and mixed fiber metabolite content were used to assess the major biochemical pathways. The results demonstrate a preponderance of fast-twitch fibers in the locomotor muscles of cheetahs; 83% of the total number of fibers examined in the vastus laterali...
