Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Gerhards H.Antithrombin III (AT III) determinations were done in healthy and sick horses using the chromogenic substrate Chromozym TH. Reference values for adult horses at 25 degrees C were 18-25 IU AT III per ml plasma and 84-118% AT III activity of normal horse plasma, respectively. Precision and accuracy were good (intra assay coefficient of variation less than 2%, accuracy 10%). Surgical operations on healthy horses led to a biphasic decrease in AT III activity touching the lower border of the reference values on the second postoperative day. Other reasons for acquired AT III deficiencies included di...
Junnila M, Korkeala H, Rahko T, Salmi A.The kidney cortex of 32 Finnish horses was analysed chemically for cadmium (Cd) and selenium (Se) content and by light microscopy for histopathological changes of the tissues. Cd concentrations in kidney cortex ranged from 6.9 to 91.6 mg/kg wet weight with an average of 31.9 mg/kg. Se concentrations ranged from 0.5 to 1.5 mg/kg with an average of 1.0 mg/kg. The age of the horses varied from 1.5 to 32 years; mean age was 16 years. Cd levels in kidney cortex seemed to increase linearly up to an age of about 16 years. In old (over 16 years) horses no such correlation could be found. Se concentrat...
Madej A, Kindahl H, Nydahl C, Edqvist LE, Stewart DR.Two mares received PGF-2 alpha twice daily until abortion and 2 mares received a combined treatment with oestradiol benzoate and oxytocin. The mares were about 150 days pregnant. The PG-treated animals aborted after 37 and 61 h, respectively, and the fetuses were expelled in intact fetal membranes. The other 2 mares aborted 13 and 27 h after the first oxytocin injection, respectively, and showed strong uterine contractions and expelled the fetuses in disrupted fetal membranes. Concentrations of 15-ketodihydro-PGF-2 alpha increased both after PG and oxytocin injections and in association with t...
Johnson AL.Experiments were conducted in the horse mare to study the effects of photoperiod and season on serum prolactin and pituitary responsiveness to thyrotropin-releasing hormone (TRH). Increasing the photoperiod to 16 hr light:8 hr dark beginning in December (Experiment 1) and September (Experiment 2) increased serum prolactin, but the rate of increase was greater when the photoperiod treatment was initiated in September. In addition, TRH-induced prolactin secretion was found to be affected by season, in that pituitary secretion (net increase in prolactin and total prolactin secreted) was significa...
Hyland JH, Wright PJ, Clarke IJ, Carson RS, Langsford DA, Jeffcott LB.In Exp. 1, 30 Standardbred mares in deep seasonal anoestrus were divided into 3 equal groups and treated with 0, 50 (G50) or 100 (G100) ng GnRH kg-1h-1 for 28 days via osmotic minipumps. Ovulation occurred in 0/10, 3/10 and 7/10 mares respectively (P less than 0.05). Plasma GnRH profiles (Days -6, 0, 2, 6, 12, 20, 28 and 34 relative to pump insertion) were dose-dependent (P less than 0.01) and peaked on Day 12 of infusion. Mean daily plasma LH concentrations were biphasic in treated mares that ovulated, with LH peaks occurring around Day 6 and Days 16-20. By contrast, in treated mares that did...
Yamamoto M, Yamamoto I, Tanaka Y, Sugano M.1. A method for the purification of horse serum lecithin:cholesterol acyltransferase has been established. 2. The method involves the adsorption of the enzyme from diluted horse serum on DEAE-Sephadex A-50, (NH4)2SO4 fractionation, 1-butanol treatment, and chromatographic techniques of DEAE-Sepharose CL-6B, DEAE-Sephadex A-50, Affi-Gel blue and hydroxylapatite. 3. The resultant enzyme preparation essentially formed a single main band when subjected to polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. 4. The final purification of the enzyme was 20,000-fold with 7% yi...
Stammers JP, Leadon DP, Hull D.The fatty acid composition of the plasma free fatty acid, triacylglycerol and phospholipid fractions was measured in blood and milk samples taken daily from 3 mares and their foals on Days 1-9 post partum inclusive, and from a total of 12 mares and foals on Days 22, 30 and 51. A rise in the plasma concentrations of triacylglycerol and phospholipid similar to that well documented in other species occurred in the neonatal period. Alterations in the composition of the foal plasma phospholipid after birth lend support to the view that the placenta rather than the fetus could be responsible for the...
Silver M, Fowden AL, Knox J, Ousey JC, Franco R, Rossdale PD.The effects of insulin-induced hypoglycaemia on plasma catecholamines, cortisol and metabolites have been examined in newborn and 7-14-day-old foals. The fall in plasma glucose elicited by the highest dose of insulin (1.0 i.u./kg) given to the neonates was slower in onset and less severe in effect than 0.5 i.u./kg in the older foals. There was a significant inverse correlation between the concentrations of glucose and adrenaline (but not noradrenaline) in plasma once the glucose level had fallen below 2 mmol/l; the adrenergic response to hypoglycaemia was greater in the 7-14-day-old foals than...
Caron JP, Barber SM, Doige CE, Pharr JW.This study documented the normal histologic features of the equine metacarpal and metatarsal periosteum and characterized its osteogenic response to surgical manipulation. Two periosteal flaps were elevated from the dorsomedial matacarpal and metatarsal diaphysis in each of three limbs of four yearling and four adult lightbreed horses. The superficial metacarpal cortex under the flap was resected with a bone chisel in one-half of the horses and was undisturbed in the remainder. One periosteal flap in each limb was excised and the other flap was replaced and secured by sutures. All limbs in the...
McDowell KJ, Sharp DC, Grubaugh W.Eight ovariectomized pony mares were used to test the effect of various doses of progesterone (0, 50, 150, 450 mg/day, in oil, i.m., for 10 days) on progesterone and LH in the peripheral circulation, and on total protein and uteroferrin in uterine secretions. Progesterone increased uteroferrin, but there were no differences amongst doses of progesterone. Progesterone treatment decreased LH, and tended to increase total protein. Eighteen ovariectomized mares were given vehicle, oestradiol (10 mg/day, in oil, i.m.), progesterone or progesterone + oestradiol for 28 days. Both the last two steroid...
Eysker M, Wemmenhove R.The epidemiology and control of helminth infections in the horse were studied in four small grazing experiments between 1981 and 1984 at the University of Utrecht. At autopsy in November or December negligible Strongylus vulgaris burdens were found in the cranial mesenteric artery of four groups of ponies, which had been treated with an anthelmintic in July and subsequently transferred to a clean pasture. Considerable arterial S. vulgaris burdens were seen in three groups of ponies which were treated with an anthelmintic in July without a move to clean pasture, and in another group of ponies i...
Antczak DF, Oriol JG, Donaldson WL, Poleman C, Stenzler L, Volsen SG, Allen WR.Monoclonal antibodies raised against horse placenta were tested using an indirect immunoperoxidase-labelling technique for reactivity with a panel of tissues from adult horses and conceptuses of various gestational ages. The pattern of reactivity of 4 of the antibodies (F67.1, F71.3, F71.7, F71.14) on trophoblastic tissues described unique antigenic phenotypes for the non-invasive trophoblast of the allantochorion, the invasive trophoblast of the chorionic girdle, and the mature endometrial cup cells, which are derived from the chorionic girdle. Two of the monoclonal antibodies (F67.1 and F71....
von Fellenberg R.The importance of proteases and protease inhibitors for the pathogenesis of pulmonary emphysema and chronic bronchitis of the horse is described. Endogenous elastases from neutrophil granulocytes and macrophages, which probably provoke emphysema in the human being, are not relevant in horse emphysema. Exogenous elastases from different species of streptomyces may be responsible for emphysema generation in this species. Part of the exogenous elastases are poorly or not inhibited at all by the equine blood protease inhibitors especially by alpha 1-protease inhibitors. A disorder similar to genet...
Crump A, Donaldson WL, Miller J, Kydd JH, Allen WR, Antczak DF.Antibodies to fetal major histocompatibility complex (MHC) antigens are routinely detected in the serum of pregnant mares some 2-4 weeks after formation of the endometrial cups at Day 36-38 after ovulation. Several experimental approaches were taken to determine whether paternal MHC antigens are expressed on horse placental tissues. First, absorption of anti-paternal MHC antisera with a large volume of endometrial cup cells removed antibody activity in only 2 of 4 experiments. Second, repeated immunization of horses with endometrial cup tissue recovered from a mare on Day 47 of pregnancy faile...
Blaze CA, Robinson NE.Apneic oxygenation was studied in six ponies for 30 minutes, and six horses for 10 minutes. Arterial blood was sampled at regular intervals for measurement of oxygen and carbon dioxide tensions (PaO2 and PaCO2) and calculation of alveolar-arterial oxygen tension difference (PAO2-PaO2). In both groups of animals, PaO2 decreased rapidly during the first 3 minutes of apnea, then more slowly. Although the mean value was above 100 mmHg at 10 minutes, there was considerable inter-animal variability. Before apnea, PAO2-PaO2 was slightly, but not significantly, larger in horses than in ponies and incr...
Wilson DG, Reinertson EL.A modified parainguinal approach was used to castrate 119 abdominal cryptorchid horses. The operative time ranged from 10 to 30 minutes. Follow-up information was obtained for 107 horses. Swelling, more severe than that expected in routine castrations, was reported in six horses. An incisional abscess had to be drained in one horse and one horse died of unexplained causes 3 days after the surgery.
Bell JU, Lopez JM, Bartos KD.1. Serum samples were collected from ten foals at predetermined times during the first 12 months following birth and zinc and copper concentrations and ceruloplasmin activity were evaluated. 2. Serum zinc concentrations were found to be quite variable with respect to age (range = 67-95 micrograms/dl). 3. Serum copper concentrations increased in a linear fashion from day 0 to day 28 before levelling off at 190-247 micrograms/dl. 4. Ceruloplasmin activity was found to correlate with the concentration of serum copper (r = 0.92) and reached a plateau at an activity of 30-38 IU by day 28.
Duchamp G, Bour B, Combarnous Y, Palmer E.Injection of hCG (2000-2500 i.u., i.v.) to mares when a follicle reaches 35 mm induces ovulation between 24 and 48 h. However, repeated injections induce antibodies against hCG. We report attempts to induce ovulation without this inconvenience. We called 'response' an ovulation between 24 and 48 h after treatment. The typical response to hCG was obtained in 73% (N = 145) of treated mares. After immunization against hCG, the response (0%, N = 10) was less than in nonimmunized controls (100%, N = 9). Simultaneous injection of dexamethasone and hCG resulted in induction of ovulation (71%, N = 14)...
Penn D, Dolderer M, Schmidt-Sommerfeld E.Carnitine concentrations were measured in the milk of sheep, cows, goats, and horses, in human milk of term and preterm infants and in European infant formulas. There were significant species' differences in carnitine milk content. Acylcarnitine concentrations ranged from 13 to 47% of total carnitine. This may be related to differences in maternal and/or mammary gland metabolism. The concentration of long-chain acylcarnitine in milk was under 1% in all investigated species. In cow's milk, there was a decrease in acylcarnitine concentration during the first 2 months of lactation. In human milk,...
O'Callaghan MW, Hornof WJ, Fisher PE, Rabbe OG.This study describes the development of a radioaerosol technique for horses using 99mtechnetium-DTPA (diethylenetriaminepentacetate). In 24 normal, adult horses, very satisfactory ventilation images were obtained with the technique. Four-minute administrations of the aerosol resulted in a mean uptake of radioactivity in the lung fields of 3.02 mCi, with mean maximum counts (+/- sd) of 159,800 +/- 75,000 per camera field. The mean clearance half-time for the 99mtechnetium-DTPA from the lung fields was 55.6 +/- 14.2 mins which is very similar to figures obtained for normal human and dog lungs. T...
Ousey JC, Rossdale PD, Cash RS, Worthy K.Multiparous pregnant mares, on two studfarms, were studied following natural challenge with equid herpesvirus-1 (EHV-1). They were divided into three groups according to serum complement fixation titres: Group A (N = 11) were not challenged and delivered normal foals; Group B (N = 13) were challenged but delivered normal foals; Group C (N = 23) were challenged and delivered infected foals which were stillborn or lived for less than 31 h. In Groups A and B mean (+/- s.d.) gestational age at delivery was 343 (+/- 8) and 339 (+/- 8) days respectively, whereas in Group C it was significantly (P le...
Little TV, Woods GL.The accessory sex glands of 10 stallions were examined by transrectal ultrasonography. Seminal vesicles were 26.4 +/- 5.2 (s.d.) mm in width and 9.2 +/- 3.1 mm in height. Ampullae were 16.3 +/- 3.6 mm in width and 12.9 +/- 3.9 mm in height. Bulbourethral glands were 19.7 +/- 4.6 mm in width and 32.4 +/- 6.7 mm in length. Prostate lobes exceeded 34 mm in width and were 23.5 +/- 5.7 mm in height. The prostatic isthmus was 6.0 +/- 1.4 mm in height. The seminal colliculus, masculine uterus, and deferent ducts were also identified and characterized. Five of these stallions were killed to compare tr...
Boyle MS, Cran DG, Allen WR, Hunter RH.The morphology of the uterotubal junction (UTJ) and caudal isthmus during the peri-ovulatory period, and the distribution of spermatozoa within the region, were studied in 10 Pony mares. The proximal tip of the uterine horn and caudal 1-2 cm of the isthmus were removed during oestrus or shortly after ovulation from animals mated or artificially inseminated within the previous 24 h. The tissues were incised longitudinally and fixed for scanning electron microscopy. Analysis of micrographs showed deep longitudinal and oedematous folds in the preovulatory samples. After ovulation, much of the fol...
Sprouse RF, Garner HE, Green EM.Thirteen (65 per cent) of 20 horses subjected to carbohydrate overload developed Obel Grade 3 lameness within 56 h. Increases in plasma endotoxin from control levels of less than 0.1 ng/litre to values ranging from 2.4 to 81.53 ng/litre were measured in 11 (85 per cent) of 13 horses during the onset of Obel Grade 3 lameness. Obel Grade 3 lameness was associated with rises in plasma Gram-negative endotoxin levels in 11 (92 per cent) of 12 horses. Two peak increases separated by 16 h were verified in five (45 per cent) of 11 horses that exhibited both endotoxaemia and Obel Grade 3 lameness. The ...
Frewein J, Buff E.In the anatomical literature there are inconsistencies in the description of the levatores costarum muscles in man and in the domestic animals, and their innervation either by the dorsal or the ventral branches of the thoracic nerves. Therefore we studied the form, structure and, with the aid of the dissecting microscope, the innervation of these muscles in 7 dogs, 8 cats, 5 horses and 12 pigs. In the dog, cat and horse, mm. levatores costarum are present from the second to the last rib. In the pig, these muscles are present from the second to the 15th rib, even in individuals with 16 pairs of...
Allen WR, Sanderson MW, Greenwood RE, Ellis DR, Crowhurst JS, Simpson DJ, Rossdale PD.A total of 18 experimental pony and 136 commercial maiden, barren and foaling Thoroughbred mares in seasonal or lactation-related anoestrus were injected subcutaneously with 1 or 2 slow-release D,L-lactide-glycolide co-polymer implants impregnated with 0.9 or 1.8 mg of the potent GnRH analogue, ICI 118 630, to give a daily release of, respectively, 30 or 60 micrograms analogue for 28 days; 32 of the Thoroughbred mares were also given a daily oral dose of 27.5 mg allyl trenbolone for 5 days after injection of the implant. Thirteen pony (76%) and 120 Thoroughbred (88%) mares ovulated 3-18 days a...
Wawrzeńska M.In this paper, the effect of ascorbic acid on motoric activity of the intestines of rabbits, pigs, cows, sheep and horses has been determined, and a possible participation of the adrenogenic system in this mechanism has been shown. In experiments in vitro the motility of the duodeum, jejunum, caecum and colon in the animals mentioned abowe was recorded by the method of Magnus after administration of ascorbic acid. Diastolic reactions were observed in all animals, which were much greater in small intestines than in large ones. To elucidate the diastolic mechanism under the influence of ascorbic...
Goff AK, Pontbriand D, Sirois J.In Exp. 1, 4 mares were given oxytocin intravenously (10 i.u./500 kg body wt) daily between Days 9 and 14 (Day 0 = day of ovulation) when pregnant and on Days 9-14, 16, 18, 20 when non-pregnant (not inseminated). In the non-pregnant mares the increase in plasma PGFM response to oxytocin was greater at Day 13 (235 +/- 54 pg/ml) than at Day 11 (113 +/- 38 pg/ml; P less than 0.05) and was maximum at Day 16. However, these animals did not return to oestrus and plasma progesterone did not fall below 4 ng/ml. There was no significant increase in response to oxytocin between Days 9 and 14 in the preg...
Ducharme NG, Horney FD, Baird JD, Arighi M, Burton JH.The effect of resection of 75% (length measurement) of the large colon in ponies was studied. Ten ponies in good physical condition were divided into two groups: group I consisted of the six experimental ponies and group II of four control ponies. Preoperatively and postoperatively for five months, ten clinicopathological parameters were determined: body weight, venous blood pH, plasma bicarbonate, total plasma protein concentration, serum electrolyte values (sodium, potassium, chloride), and fecal osmolarity. Subjective assessment of attitude and appetite revealed no difference between the gr...
Parraga ME, Kittleson MD, Drake CM.The aim of this study was to determine if quinidine administration increases steady state serum digoxin concentration in horses. Digoxin (0.01 mg/kg q. 12 h per os) was administered to 6 horses for 7 days. Steady state was confirmed by identifying statistically indistinguishable peak and trough serum digoxin concentrations on Days 4, 5, and 6. On Day 6, serum digoxin concentration was measured at baseline and 0.25, 0.5, 1, 2, 4, 6, 8 and 12 h after digoxin administration. On Day 7, quinidine (20 g at baseline and 10 g at 2, 4 and 6 h) was administered per os and serum digoxin concentration was...
Hood DM, Brumbaugh GW, Wagner IP.To determine whether a unique dihydropyridine (BAYTG 1000) would be beneficial in preventing laminitis in horses. Methods: 16 clinically normal adult horses. Methods: 8 pairs of horses were used in a controlled double-blind study, using sex- and age-matched horses randomly assigned to treatment or control groups. Horses were subjected to carbohydrate overload to induce laminitis. Treated horses were administered BAY TG 1000 (30 mg/kg, PO, q 24 h) for 3 days. Hoof wall surface temperature (HWST) and lameness were recorded at 4-hour intervals. The HWST was adjusted on the basis of time of onset ...
Bergman HJ, de Kruif A.In this last article the veterinary supervision of problem mares at the stud is reviewed. Treatment possibilities are evaluated. The usefulness of treatment with progestagens in order to sustain pregnancy or to prevent embryonic death is discussed.
Hwang J, Golla V, Metwali N, Thorne PS.Adverse respiratory health effects in the agricultural industry have been linked to particulate endotoxin exposure. However, whether the endotoxin concentration is significantly correlated to the size of the particle remains an open question. To date, limited research has been conducted to assess particulate endotoxin exposures in the agricultural industry in general or the equine industry in particular. A task-based exposure assessment was conducted to characterize the endotoxin levels of inhalable and respirable particles on four Kentucky farms during the summer season. We conducted personal...
McD○ LA, Stover SM, Bach JM, Taylor KT.To determine the mechanical properties of Equine Interlocking Nail (EIN; JD Wheat Veterinary Orthopedic Research Laboratory, University of California, Davis) stabilized osteotomized tibiae and compare these variables with estimated in vivo loads. Methods: In vitro biomechanical investigation. Methods: Twelve adult equine cadaveric tibiae. Methods: EIN-stabilized tibiae were tested monotonically under compression, 3- and 4-point bending, and torsion. Mechanical properties were compared with estimated in vivo loads. Results: EIN-tibial composite mean compressive yield load (11 kN) and bending mo...
Lavoie-Lamoureux A, Martin JG, Lavoie JP.Neutrophils are the predominant cells recruited in the airways of horses suffering from heaves. These cells have been shown to express arginase in some species. The metabolism of l-arginine is thought to be involved in chronic inflammation, and airway obstruction and remodeling. The aim of this study was to assess the expression, regulation, activity, and functional role of arginase isoforms in equine neutrophils. Arginase I, arginase II, ornithine decarboxylase (ODC) and ornithine aminotransferase (OAT) expression were assessed in resting and stimulated (IL-4, LPS/fMLP, PMA; 5 and 18 h) blood...
Seidel GE.Principles and procedures for cryopreservation of equine embryos are described. Embryos less than 250 microM in diameter can be cryopreserved successfully if glycerol is used as the cryoprotectant. Cooling is takes place in such a way that most of the water leaves the cells before intracellular ice forms, and glycerol is removed after thawing without undue osmotic swelling of cells. Vitrification procedures also show promise for small embryos. Satisfactory procedures for cryopreserving embryos of more than 250 microM in diameter are not yet available.
Henderson IS, Brama P, Osborne M, Beltman ME.Deslorelin acetate implants, recently licensed in Ireland and the UK for ovulation induction in mares, have been associated with prolonged interovulatory intervals in USA studies, leading to the practice of removing implants postovulation. Trial data in Australia indicate a less pronounced effect on interovulatory intervals, suggesting possible geographical variation. Objectives of the current study were to assess the effect of deslorelin implants, with and without removal on oestrous cycle length in Irish- and UK-based Thoroughbred broodmares. Data were collected retrospectively from 88 oestr...
Munroe G.Twenty-seven of 167 neonatal thoroughbred foals (16 per cent) were found to have retinal haemorrhages after a careful examination of the entire fundus. Experience in differentiating haemorrhages from other lesions, and the selection of foals from normal populations, were considered to have an important effect on their apparent incidence. Bilateral haemorrhages were more common and there was a significantly higher incidence in female foals. The numbers of haemorrhages ranged between one and 20; 36 per cent of eyes with retinal haemorrhages had the small punctate type and 56 per cent had the spl...
Pozio E, Tamburrini A, Sacchi L, Gomez Morales MA, Corona S, Goffredo E, La Rosa G.Routine examination for Trichinella infection by artificial digestion of 5-g samples of muscle tissue revealed the presence of muscle larvae in one out of 28 horses imported from Romania to an abattoir in Italy. The parasite, identified as Trichinella spiralis by the polymerase chain reaction, showed a reproductive capacity index of 68 in Swiss mice. Light microscope examination of 200 nurse cell-larva complexes showed that 22% of them were calcified and that the capsules of the non-calcified nurse cells were 17.5-27.5 microns (s = 22.67 microns) thick and had very few cellular infiltrates. Th...
Schoenborn WC, Rick MC, Hornof WJ.A 6-year-old Thoroughbred gelding presented with a left forelimb lameness. The results of lameness examination, radiography, nuclear scintigraphy, and computed tomography are presented. Based on the diagnostic imaging, subchondral fractures and osteochondritis dissecans lesions of the proximal articular surface of the proximal phalanx were diagnosed. A brief discussion of osteochondritis dissecans is presented.
Mozzaquatro FD, Verstegen JP, Douglas RH, Troedsson MH, Delacorte FD, Silva CA, Rubin MI.Ultrasound-guided follicular aspiration was performed in 26 Criollo crossbred mares, followed by the evaluation of ultrasonographic images of the Corpus luteum (CL) that was formed after puncture of follicles of different diameters (Group 25-29 mm; Group 30-35 mm and Group >35 mm). Serum progesterone (P(4) ) concentrations were measured to determine CL function. The size of the CL was measured and the CL was classified based on the following echoscore: 1- anechoic tissue; 2- poorly defined luteal structure with low echogenicity; 3- echogenicity analogous to a luteal structure. The proport...
Kaminski M, Metenier L, Sykiotis M, Ryder OA, Demontoy MC.1. Among several species of Equidae only E. przewalskii possesses a serum esterase identical with that of E. caballus. 2. The esterases of Hemionidae differ slightly from that of domestic horse by electrophoretic migration and by antigenic structure. 3. Zebras (grevyi, burchelli) appear devoid of this component but Z. hartmannae possesses an esterase of high enzymatic activity, differing notably from that of horse by electrophoretic and antigenic properties.
Schneider RK, Andrea R, Barnes HG.An open, contaminated, comminuted fracture of the radius of a 500-kg adult horse was diagnosed. Antibiotic-impregnated polymethyl methacrylate implants were placed into the fracture site to help eliminate infection from the limb. Later in the course of treatment, lag screws were placed across the fracture to generate compression and healing. The fracture healed, and the horse was released to its owners. The implants were not removed, and only a mild lameness existed 90 days later.
Powers SK, Beadle RE, Thompson D, Lawler J.The purpose of these experiments was to examine the temporal pattern of arterial carbon dioxide tension (PaCO2) to assess the relationship between alveolar ventilation (VA) and CO2 return to the lung at the onset and offset of submaximal treadmill exercise. Five healthy ponies exercised for 8 min at two work rates: 50 m/min 6% grade and 70 m/min 12% grade. PaCO2 decreased (P less than 0.05) below resting values within 1 min after commencement of exercise at both work rates and reached a nadir at 90 s. PaCO2 decreased maximally by 2.5 and 3.5 Torr at the low and moderate rate, respectively. Aft...
Evans MJ, Irvine CH.Deeply acyclic (seasonally anovulatory) mares were treated with GnRH or a GnRH analogue to induce follicular development and ovulation. Courses of GnRH (3--4) were administered at approximately 10-day intervals to reproduce the gonadotrophin surges which precede ovulation in the normal cycle. Exogenous progesterone was administered in an attempt to reproduce the luteal phase pattern. Induced serum FSH concentrations were comparable to those causing follicular development in the normal cycle, but induced LH levels were lower and of shorter duration than those of the periovulatory surge. Three o...
Harmel JL, Lewis CW, Sah RL, Kawcak CE, Wheeler DL.Millions of Americans suffer from osteoarthritis, a joint disease characterized by cartilage degradation and subchondral bone sclerosis. However, little is known about its pathology. It remains to be discovered which comes first in the progression of osteoarthritis: subchondral bone remodeling or cartilage degeneration. This study assessed equine cartilage degeneration, based upon measurements of cartilage thickness and Indian ink stain uptake. By gaining a greater understanding of the determining factors in cartilage degeneration, we may be able to better understand the pathomechanics of oste...
Underwood C, Collins SN, Mills PC, Van Eps AW, Allavena RE, Medina Torres CE, Pollitt CC.Pharmaceutical agents with potential for laminitis prevention have been identified. Many of these, including the MMP inhibitor marimastat, are impractical for systemic administration. This study compared local delivery of marimastat by regional limb perfusion (RLP) to systemic intravenous bolus dosing (SIVB), and established whether RLP results in local lamellar drug delivery. Six adult horses received 0.23 mg/kg of marimastat by RLP followed by 0.23 mg/kg marimastat by SIVB, with a 24-h washout period. Lamellar ultrafiltration probes sampled lamellar interstitial fluid as lamellar ultrafiltra...
Boulton EP, Seeherman HJ, Kirker-Head CA, Steckel RR.Laryngotomy incisions for either staphylectomy, ventriculectomy, cordectomy, resection of the palatopharyngeal arch, or subepiglottal cyst removal, were closed primarily in 42 horses. Incisional complications were subcutaneous emphysema (11 horses, 26%), incisional discharge (4 horses, 10%), postoperative fever (4 horses, 10%), incisional abscessation (3 horses, 7%), incisional seroma (2 horses, 5%), and subcutaneous edema (2 horses, 5%). Incisional complications were identified in 22 horses, but only 8 horses (19%) required intervention for incisional healing to occur. Factors such as preoper...