Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Equine Health
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.
Exploring the possible functions of equine hoof wall tubules. Possible functions of equine hoof wall tubules were investigated in this study. Hydration tests were conducted on blocks of hoof wall tissue in order to test the hypothesis that hollow tubules facilitate the conduction of water vapour distally. Although water loss or gain was inhibited through the outer wall surface, the increase in surface area provided by medullary spaces was ineffective in facilitating hydration through the face with exposed tubule ends. Rather, hollow tubules appear to allow for a higher dehydration rate through their exposed ends. Analysis of medullary space indicates tha...
Equine laminitis basement membrane pathology: loss of type IV collagen, type VII collagen and laminin immunostaining. Disintegration of the basement membrane (BM) of the equine hoof lamellae and failure of the BM to remain attached to the basal cells of the secondary epidermal lamellae (SEL) is one of the earliest pathological events to occur in acute laminitis. Changes in the lamellar basement membrane were investigated by immunolabelling the key structural components of the BM, type IV collagen, type VII collagen and laminin in the lamellar BM of horses 48 h after the induction of laminitis. Lamellar tissues were harvested from 2 normal horses and 2 horses with acute laminitis. Immunostaining with antibody ...
Variation in surface strain on the equine hoof wall at the midstep with shoeing, gait, substrate, direction of travel, and hoof shape. Objectives were to examine the deformation of the healthy equine front hoof during locomotion, by recording strains on its outer surface, and to test whether its mechanical behaviour is significantly altered under different locomotory conditions and variation in hoof shape. Strains were recorded in vivo from 5 rosette gauges around the circumference of the right forehooves of 12 horses. The magnitudes and orientations of principal strains at the midstep were compared statistically for different conditions of shoeing (shod vs. unshod), gait (walk vs. trot), substrate (treadmill vs. ground), and...
Tubule density of the stratum medium of horse hoof. The number of tubules/mm2 (tubule density) of horse hoof horn was quantified in samples taken from the left forefeet of 8 randomly selected slaughterhouse horses in order to establish the normal tubule density characteristics at the midline dead centre (MDC) for the stratum medium of horse hoof. In the past the measurement of tubule distribution within the hoof has lacked objectivity. The horse hoof tubule density results are compared to a recent objective study carried out on pony hoof. A similar 4 zone pattern of tubule density was observed, although the precise zonal boundaries and tubule d...
In vitro attenuation of impact shock in equine digits. This study was designed to test the impact characteristics of the equine digit in vitro with the objective of providing a better understanding of the role of the digital structures in the attenuation of impact shock. Uni-axial accelerometers were mounted on cadaver digits on the distolateral hoof wall, the proximolateral hoof wall, the dorsal surface of the second phalanx, and the mid-lateral first phalanx. The hoof-mounted accelerometers were aligned with the hoof tubules while the bone-mounted accelerometers were oriented along the longitudinal axis of the bone. Each digit was mounted in a t...
Equine laminitis: its development coincides with increased sublamellar blood flow. The effect of alimentary carbohydrate overload on hoof temperature was investigated to determine the state of the sublamellar vasculature preceding the onset of equine laminitis. Hoof, core and ambient temperatures and heart rate were logged continuously in 21 mature Standardbred horses kept in an environmental chamber set at 10 degrees C. Recording hoof temperature was a successful, noninvasive, method to measure indirectly, shifts in digital blood flow against a background of cold induced, physiological, vasoconstriction. High hoof temperatures were assumed to indicate digital vasodilation a...
Effect of supplementary dietary biotin on hoof growth and hoof growth rate in ponies: a controlled trial. The effect of dietary biotin supplementation, at a dose rate of 0.12 mg/kg bwt, on growth and growth rate of the hooves of 8 match-paired poines was investigated in a controlled feeding trial. Treatment animals had a mean hoof growth at the midline dead centre of the hoof capsule of 35.34 mm after 5 months of biotin supplementation compared to control animals 30.69 mm (P < 0.05). Comparison of regression analysis also showed that biotin supplementation produced a significantly higher (P < 0.02) growth rate of hoof horn in this trial. Treatment animals had a 15% higher growth rate of hoof horn ...
Preliminary observations in in vitro development of equine embryo after ICSI. The objective of this study was to perform intracytoplasmic sperm injection (ICSI) on in vitro matured equine oocytes and to improve in vitro embryonic development on Vero cells after activation of the microinjected oocytes with calcium ionophore. After maturation (23 or 40 h, 38.5 degrees C, 5% CO2), the cumulus-oocyte complexes were denuded, centrifuged and all oocytes exhibiting the first polar body were microinjected. ICSI was performed using fresh semen from three fertile stallions. Microinjected oocytes were activated with calcium ionophore A23187 (10 min, 10 microM) and cultured individ...
Effect of hoof trimming on the occurrence of distal phalangeal palmar process fractures in foals. This study sought to determine if extensive trimming of the front hooves of foals results in a higher incidence of palmar process fractures compared to untrimmed foals, and to characterise the clinical course of foals with palmar process fractures with physical findings, hoof measurements and radiography. Twenty foals age 4-8 weeks of multiple breeds were examined every 2 weeks over a 12 week period. Ten foals had both front hooves extensively trimmed every 4 weeks, while 10 foals remained untrimmed. Palmar process fractures occurred in 4 trimmed and 3 untrimmed foals. Four foals with fracture...
Finite element analysis of static loading in donkey hoof wall. A finite element model of donkey hoof wall was constructed from measurements taken directly from the hoof capsule of the left forefoot. The model was created with a 2 mm mesh and consisted of 11,608 nodes. A linear elastic analysis was conducted assuming isotropic material properties in response to a 375 newton (N) load, to simulate static loading. The load was applied to the wall via 400 laminae in order to simulate the way in which the pedal bone is suspended within the donkey hoof capsule. Displacement, stress concentration, principal strain, and force distribution across the hoof wall were...
Effect of rider and riding style on deformation of the front hoof wall in warmblood horses. A rider modifies the weight distribution and dynamic balance of the horse. But what effect does a rider have on the mechanical behaviour of the hoof during each stance phase? Does riding style have any effect on this behaviour? We attempted to answer these questions using strains recorded from 5 rosette strain gauges glued to the surface of the front hooves of 4 Warmblood horses. Comparisons were made between strains with and without a rider, and when the rider was sitting, rising at a trot, or in a forward seated position. The change in strains from trot to lead or nonlead at a canter, and th...
Effect of a supplementary dietary evening primrose oil mixture on hoof growth, hoof growth rate and hoof lipid fractions in horses: a controlled and blinded trial. The lipid chemistry of the normal equine hoof, together with the effect of oral supplementation with an evening primrose oil mixture (EPOM) on its growth, growth rate and lipid content was assessed in a controlled and blinded feeding trial at the Defence Animal Centre. Twelve horses were paired as closely as possible according to sex, age, weight, height and colour and then one from each pair was randomly allocated to treatment or control groups. The treatment group received 30 ml of oral EPOM/day, otherwise the nutrition and management regimes were the same for all horses. No significant diff...
Batimastat (BB-94) inhibits matrix metalloproteinases of equine laminitis. A method for culturing explants of lamellar hoof was developed to investigate the process of lamellar separation that occurs in laminitis. Explants, consisting of hoof wall, dermal and epidermal lamellae and the adjacent sub-lamellar connective tissue remained intact when cultured in tissue culture medium for 2 days. However, when cultured in the presence of the matrix metalloproteinase (MMP) activator aminophenylmercuric acetate (APMA), the lamellae separated when tension was applied by pulling the hoof wall in an opposite direction to the connective tissue. The separation occurred between th...
A permeability barrier in the dorsal wall of the equine hoof capsule. The permeability barrier in the dorsal wall of the equine hoof capsule was studied by means of horseradish peroxidase (HRP) in 0.9 N saline solution as a water soluble tracer. Section were treated with 3'3'-diaminobenzidine tetrachloride (DAB) and before dissection the quality of the horn of feet from 10 horses was assessed and given a subjective grade as either good or poor. Blocks of tissue from each horse were left in either an oven at 60 degrees C or in water for 2 weeks before treatment in HRP, sectioning and DAB solution. Regions observed were i) outer surface, ii) outermost layers of th...
Fetal development of the white line (Zona alba) of the equine hoof. The fetal development of the white line (Zona alba) in the equine hoof is described. Its specific structure of lamellar and interlamellar horn, which in turn is composed of cap and terminal horn, is formed in the second half of the hoof's fetal development. In equine fetuses with a crown-rump length of less than 550 mm, the hoof capsule lacks a 'characteristic' white line since no borders between stratum medium, stratum internum and sole horn are discernible. In the hoof of an equine fetus with a crown-rump length of 550 mm, a narrow white line has taken shape. Its shallow lamellae are arrange...
Onychomycosis in white line disease in horses: pathology, mycology and clinical features. This paper describes onychomycosis in horses and reports the pathological findings, associated fungi and incidence of concurrent white line disease. In addition to these observations, relevance between post mortem and clinical findings of onychomycosis are discussed in 3 necropsied horses. Samples were collected from 100 hooves from a total of 51 Thoroughbreds suffering from white line disease. Of these, 15 hooves from 13 horses were also complicated with severe hoof wall fissure formation. Preparations from the same samples were used both for histopathology and for culture to identify the ass...
Cytokeratins of the equine hoof wall, chestnut and skin: bio- and immunohisto-chemistry. 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...
Effects of season and diet on tensile strength and mineral content of the equine hoof wall. Studies evaluating nutritional and seasonal influences on hoof strength and composition in horses, as well as the scientific justification for feeding supplements to improve hoof quality, are lacking. The horseman and veterinarian need controlled studies in this area to make informed decisions. This project quantified, in 2 trials, relative elasticity, tensile strength, % moisture, and mineral composition of hooves of 48 mature Thoroughbred mares maintained on different nutritional/management regimens, sampled quarterly over 12 month periods. Tensile strength was positively associated with sul...
Decreased glucose metabolism causes separation of hoof lamellae in vitro: a trigger for laminitis? Explants of horses' hooves remained intact for up to 8 days when incubated in Dulbecco's modified Eagle medium (D-MEM) containing 25 mmol/l glucose but separated within 36 h when incubated in saline. The separation occurred between the basal epidermal cells and their basement membrane which is characteristic of the hoof separation that occurs in laminitis. Separation of hoof explants was prevented by addition of glucose to saline and was induced by adding 2-deoxyglucose or aminophenylmercuric acetate to D-MEM. Glucose consumption by the hoof explants was inhibited by 2-deoxyglucose and aminoph...
Digital perfusion, evaluated scintigraphically, and hoof wall growth in horses with chronic laminitis treated with egg bar-heart bar shoeing and coronary grooving. Nuclear scintigraphy was used to assess digital perfusion before and after treatment in 10 horses with clinical and radiographic evidence of chronic laminitis. Horses were evaluated for lameness, degree of distal phalanx rotation, and heel-toe hoof wall growth ratio, and randomly divided into two treatment groups. Group 1 horses received only egg bar-heart bar shoeing; Group 2 underwent egg bar-heart bar shoeing and coronary grooving. Horses were re-evaluated for digital perfusion, lameness, degree of distal phalanx rotation, and hoof wall growth at 6 week intervals over the 18 week follow-up ...
The development of microcracking and failure in bone depends on the loading mode to which it is adapted. During locomotion, the anterior cortex of the equine radius is loaded predominantly in tension, the posterior predominantly in compression. The anterior cortex is relatively strong in tension, the posterior in compression. We investigated the pattern of failure of specimens from the two cortices using laser scanning confocal microscopy. All specimens were loaded in four-point bending to increasingly higher loads. We quantified the amount of diffuse microcracking on the tensile side of these specimens by observing the amount of light emitted under laser illumination. The amount of light emitted...
A particulate viral protein vaccine reduces viral load and delays progression to disease in immunized ponies challenged with equine infectious anemia virus. Immunization regimens that induce a broadly reactive cytolytic T lymphocyte (CTL) response specific for lentiviral antigens have emerged as the leading candidates in efficacy trials conducted in both animal modelshumans. To date, lentivirus vaccination strategies have overlooked one such immunization strategy, namely the use of particulate antigens. To evaluate the efficacy of targeting antigen into the phagocytic pathway to elicit a cell-mediated immune response to lentiviral antigens, we initiated the first study of a particulate-based vaccination protocol using a large animal model system. ...
Sarcoplasmic reticulum responses to repeated sprints are affected by conditioning of horses. Sarcoplasmic reticulum (SR) responses to repeated sprints and to physical conditioning were studied in 10 Quarter Horses. Exercise tests (four repeated sprints on a treadmill) were conducted before and after 12 wk of sprint conditioning. Muscle samples from the middle gluteal muscle were taken before and after each exercise test, and SR vesicles were isolated. Calcium uptake was determined spectrophotometrically using antipyrylazo III, and Ca2+-ATPase activity was determined using an enzyme-linked optical assay. Conditioning increased calcium uptake rate and Ca2+-ATPase activity by 14 and 38%,...
Association of Clostridium difficile with enterocolitis and lactose intolerance in a foal. Diagnoses of Clostridium difficile enterocolitis and lactose intolerance were made in a neonatal foal with persistent diarrhea. It was determined that the foal had lactose intolerance on the basis of the results of a lactose tolerance test, and a diagnosis of C difficile enterocolitis was subsequently made. The foal responded to oral administration of metronidazole and lactase. Lactose intolerance is a secondary problem most commonly associated with rotavirus infection, but it can be caused by any condition affecting the small intestine. Because C difficile can affect the small intestine in fo...
Evaluation of enterolithiasis in equids: 900 cases (1973-1996). To identify breed, age, sex, physical findings, history, and outcome of treatment in horses and other equids with enterolithiasis. Methods: Retrospective study. Methods: 900 equids with enterolithiasis. Methods: Medical records from equids with enterolithiasis admitted between 1973 and 1996 were reviewed. Data on signalment, history, physical examination and clinicopathologic findings, surgical findings, and outcome were compiled from records and from telephone interviews with owners. Sex and breed predilections were determined by comparison of the study population with the general hospital po...
Incarceration of the small colon through a rent in the gastrosplenic ligament in a pony. A 10-year-old castrated male pony was examined for intermittent signs of abdominal pain of 3 days' duration. An incarceration of the small colon through a rent in the gastrosplenic ligament was found. Resection and end-to-end anastomosis were performed on the affected portion of the small colon. The pony recovered and returned to its previous degree of activity. Incarceration of the small intestine and large colon through rents in the gastrosplenic ligament are documented, although involvement of the small intestine is more common. To the best of our knowledge, incarceration of the small colon...
Endoscopy of the intertubercular bursa in horses. Forelimbs from 3 anesthetized horses and 16 fresh cadaver horses were used to describe the endoscopic anatomy of the intertubercular bursa and outline the surgical portals that provide the greatest access to structures within the bursa. A lateral arthroscopic portal was made proximal to the deltoid tuberosity of the humerus into the distal bursal recess. A second portal was created proximal to the humeral tubercles that entered the proximal bursal space. These approaches provided consistent viewing and instrument access to the lateral intertuberal groove, the greater and intermediate humeral t...
Human chorionic gonadotropin induces an inverse regulation of steroidogenic acute regulatory protein messenger ribonucleic acid in theca interna and granulosa cells of equine preovulatory follicles. The time- and gonadotropin-dependent regulation of steroidogenic acute regulatory protein (StAR) has not been characterized in vivo in preovulatory follicles of large monoovulatory species or sexually mature animals. The objectives of this study were to clone equine StAR and describe the regulation of its messenger RNA (mRNA) in equine follicles after the administration of an ovulatory dose of hCG. The screening of an equine follicle complementary DNA (cDNA) library with a mouse StAR cDNA probe revealed two forms of equine StAR that differ only in the length of their 3'-untranslated region (3'...
Variability of oxygen radical absorbance capacity (ORAC) in different animal species. The oxygen radical absorbance capacity (ORAC) was measured both in whole (ORAC-T) and deproteinized (ORAC-AS) plasma samples of human, pig, cow, rabbit, dog, cat, sheep, horse, dolphin, turkey, guinea-hen and chicken. In the 12 species, ORAC-T data, expressed as micromoles of peroxyl radicals trapped by 11 of sample, were found scattered between 8,600 and 23,000 micromol/l. The species with the highest ORAC-T values were cat among mammals and chicken among avies. ORAC-AS values ranged between 600 and 2000 micromol/l, with the highest values found in dolphin and sheep among mammals, while chick...
