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.
Physiological effects of shortening steeplechase in a 3-day-event. Various methods for modifying the Speed and Endurance portion (Day 2) of the 3-day-event have been proposed to aid horses in dealing with the hot and humid conditions expected during the next Olympic 3-day-events in Atlanta, Georgia USA in 1996. This study was designed to characterise the effects of shortening the distance required during the steeplechase (Phase B) in the face of Atlanta-like hot and humid weather conditions. Eight conditioned Thoroughbred horses (mean +/- s.e.m. age 3.75 years, range 3-5 years) underwent 3 randomised permutations of a standardised exercise test on a high spee...
The effect of naloxone administration on the secretion of corticotropin-releasing hormone, arginine vasopressin, and adrenocorticotropin in unperturbed horses. We used our nonsurgical method for collecting equine pituitary venous blood to study the role of endogenous opioids in the basal regulation of the hypothalamo-pituitary-adrenal axis. We gave mares the opioid antagonist, naloxone (NAL), at either a high (0.5 mg/kg i.v. bolus, followed by infusion of 0.25 mg/kg.h; n = 4) or low (0.2 mg/kg i.v. bolus; n = 6) dose rate. Pituitary venous blood was collected continuously, divided into 0.5- or 1-min segments for 15-30 min before and 1 h after the NAL bolus, and assayed for CRH, arginine vasopressin (AVP), and ACTH. The mares tolerated NAL administrat...
Estimation of metabolic energy cost and heat production during a 3-day-event. The metabolic power required for sustained exercise in the horse is proportional to running speed. Moderately fast speeds require substantial energy expenditure and result in the generation of a massive metabolic heat load. Quantitative estimates of energy expenditure and heat production of horses at various running speeds were developed using empirically derived data from treadmill studies. Total metabolic power represents the sum of aerobic power indicated by the rate of oxygen consumption and net anaerobic power indicated by the rate of plasma lactate accumulation. These data were applied t...
Acid:base and serum biochemistry changes in horses competing at a modified 1 Star 3-day-event. We examined the effects of participation in each of 3 modifications of Day 2 of a 3-day-event on blood and serum variables indicative of hydration, acid:base status and electrolyte homeostasis of horses. Three groups of horses - 8 European (E) horses and 2 groups each of 9 North American horses performed identical Days 1 (dressage) and 3 (stadium jumping) of a 3-day-event. E horses and one group of the North American horses (TD) performed modifications of Day 2 of a 1 Star 3-day-event and the other group of North American horses (HT) performed a Horse Trial on Day 2. Jugular venous blood was c...
Effects of hydrogen peroxide on isolated trachealis muscle of horses. During acute bouts of recurrent airway obstruction (heaves) in horses, neutrophils that are capable of increased production of reactive oxygen species accumulate in the airways. In the study reported here, the effect of hydrogen peroxide (H2O2; 1 microM to 0.1M), one of these reactive oxygen species products, on the responses of isolated trachealis muscle of horses was determined. Before and after incubation with H2O2, contractile responses to acetylcholine, electrical field stimulation (EFS), 127 mM KCl, and relaxation responses to isoproterenol and activation of the nonadrenergic noncholiner...
Failure of hyperimmune plasma to prevent pneumonia caused by Rhodococcus equi in foals. A trial was conducted on a Thoroughbred stud to determine whether or not the administration of anti-Rhodococcus equi hyperimmune plasma would reduce the prevalence of R equi pneumonia (rattles) in foals born in the 1992 horse breeding season. Hyperimmune plasma was administered to 34 foals; another 57 foals were untreated. There was no significant difference in the number of transfused foals developing R equi pneumonia compared with the untreated foals. The time required for recovery from pneumonia between the 2 groups was not significantly different.
Necropsy survey of metacarpal fusion in the horse. Paired metacarpi obtained at necropsy from 100 horses ranging in age from term fetus to 35 years were examined to estimate the prevalence and sites of metacarpal fusion. Metacarpal fusion was seen in 192 of 200 metacarpi, and 78% of all horses 2 years or older had 2 or more fusions. Fusion of the second metacarpal bone to the third metacarpal bone was significantly (P < 0.001) more common than was fusion of the fourth to the third metacarpal bone. Fusions appeared for the most part in pairs and were bilaterally symmetric. Rooney-Prickett type-A carpometacarpal joint configurations (in which...
Effect of various extenders and taurine on survival of stallion sperm cooled to 5 degrees C. Stallion semen was diluted in five different extenders (dimitro-poulus onze (Dimitro's), Kenney's modified tryode (Kenney's), modified INRA82 (INRA82), egg yolk-citrate-taurine (Citrate) and EZ-Mixin) and evaluated for motility after cooling and storage at 5 degrees C for 0, 24, 48, 72 and 96 h. EZ-Mixin extender was used as control while 70 and 100 mM of taurine were added to Dimitro's, Kenney's and INRA82 to study its effect under conditions of storage at 5 degrees C and varying processing modifications. Motility in INRA82 was 57.0, 58.4, 61.1, and 56.1% after 24, 48, 72 and 96 h, respective...
An index of the environmental thermal load imposed on exercising horses and riders by hot weather conditions. There is a need to determine objectively the environmental heat load imposed on horses competing to an international standard in 3-day-events in environments where there is likely to be a high level of radiation added to high ambient temperatures and relative humidity; the presently used FEI 'Comfort Index' is severely limited in its applicability. It is proposed that the Wet Bulb Globe Temperature (WBGT) Index be used. This index was originally established for man exercising strenuously under harsh climatic conditions with high solar radiation levels. It may be defined as: WBGT = 0.7Twb + 0.3...
Kinematic differences between the distal portions of the forelimbs and hind limbs of horses at the trot. In literature, it has been hypothesized that the concussion at impact in the equine forelimb is larger than that in the hind limb, and therefore, eventually more clinical lameness may develop in the distal portion of the forelimbs. As the functional anatomy of the distal forelimb and hind limb segments is similar, a study was undertaken to compare the kinematics of hoof and fetlock in the forelimbs and hind limbs. For this purpose, the trot of 24 clinically normal (sound) horses on a treadmill (4 m/s) was recorded, using modern gait analysis equipment. It appeared that vertical hoof velocity a...
Controlled efficacy study of the bioequivalence of Strongid C and generic pyrantel tartrate in horses. The bioequivalence of Strongid C and generic pyrantel tartrate was determined in a controlled study using 30 horses with naturally acquired endoparasitic infections. Three horses were randomly allocated to each of ten replicates based on quantitative nematode and ascarid egg counts and fecal larvae culture results. Horses within each replicate were randomly assigned to one of three treatment groups. Horses in Treatment Group 1 received only oats; horses in Treatment Group 2 received generic pyrantel tartrate pellets (2.65 mg pyrantel tartrate kg-1) mixed with oats; horses in Treatment Group 3 ...
Jejunal intussusception: a complication of functional end-to-end stapled anastomoses in two ponies. Jejunojejunal intussusception occurred after jejunal resection and stapled functional end-to-end anastomosis in two pony mares. In both mares, the lead point of the intussusception was the stapled functional end-to-end (FEE) anastomosis. The stapled free ends of jejunum were oversewn with an inverting suture pattern. A possible explanation for development of the intussusception was the acute angle created in the intestine by the FEE anastomosis. This angulation may have impaired flow of ingesta causing motility changes that predisposed the site to intussusception. Because the oversewn blind in...
Protein tyrosine phosphorylation in equine platelets: the effect of stimulation by thrombin and platelet-activating factor (PAF). Protein tyrosine phosphorylation (PTP) in thrombin- and platelet-activating factor (PAF)-stimulated equine platelet activation was investigated in the absence and presence of 2 protein tyrosine kinase inhibitors (PTKIs), methyl 2,5-dihydroxycinnamate (MDHC) and genistein. Washed equine platelets aggregated irreversibly in response to thrombin or PAF in an agonist concentration dependent fashion. MDHC produced an MDHC concentration and time dependent inhibitory effect on rate and extent of thrombin- and PAF-induced aggregations, whereas the effect of genistein on the same parameters was only ge...
Initiation of transcription and nucleologenesis in equine embryos. The time of activation of the embryonic genome (maternal-embryonic transition) in equine embryos was investigated by assessing incorporation of 3H-uridine and nucleolar development. In Experiment 1, embryos were recovered from the oviduct (n = 15) and the uterus (n = 3). Recovered embryos were assessed for morphologic development and quality score. Recovered embryos with less than 8 cells (two cells, n = 4; four cells, n = 5; five cells, n = 2) were incubated with 3H-uridine (560 microCi/ml) for 10 hr, while eight-cell embryos (n = 2), morulae (n = 2), and blastocysts (n = 3) were incubated wi...
Gunshot injuries in horses: 22 cases (1971-1993). Twenty-two horses were examined because of firearm injuries. Nine had been shot with .22-caliber bullets, 2 with BB pellets, 6 with buckshot, 1 with a .35-caliber bullet, and 1 with an airgun pellet. Injury was confined to the skin or skeletal muscles in 8 horses. Of these, 7 returned to their previous use. In 14 horses, injuries to additional structures were incurred, including the sinus and pharynx (n = 2), mandible (n = 1), tooth (n = 1), aorta (n = 1), eye (n = 3), tibia (n = 1), gastrointestinal tract (n = 3), joint (n = 1), and trachea (n = 1). The 3 horses that had only eye injuries wer...
Equine pulmonary disease: a case control study of 300 referred cases. Part 2: Details of animals and of historical and clinical findings. Examination of historical and clinical details of 270 adult horses suffering from a variety of mainly chronic pulmonary diseases showed that the chronic obstructive pulmonary disease (COPD) group (median age 9 years) were the oldest, and that the COPD, chronic idiopathic hypoxaemia and exercise induced pulmonary haemorrhage (EIPH) groups had the longest duration of disease (median durations 7, 12 and 9 months, respectively) with a median disease duration of 2 months for the remaining horses. A history of antecedent respiratory infection was present in 24.3% of all horses. Six out of 12 horses ...
Treatment and outcome of chronic tenosynovitis in three horses. Three horses were presented for treatment of chronic infections of the digital flexor tendon sheath. Clinical signs included severe lameness, and heat, pain and swelling of the digital flexor tendon sheath. The horses were treated with surgical lavage of the tendon sheath, systemic and local antibiotics, and analgesics. In each case, resolution of the lameness occurred over weeks to months. Only one horse returned to athletic activity, while the other two became comfortable at pasture. Response to treatment in cases of chronic tenosynovitis may not be as rapid or complete as that reported for ...
Fatigue behavior of the equine third metacarpus: mechanical property analysis. This is the first in a series of experiments to study the fatigue properties of equine cannon (third metacarpal) bone specimens from Thoroughbred racehorses. Monotonic and fatigue tests to failure were performed in four-point bending on diaphyseal specimens in a 37 degrees C saline bath to answer three initial questions. (a) Will a linear variable differential transducer yield the same elastic modulus as strain gauges? (b) Will fatigue results depend on whether the periosteal or endosteal side of the beam is in tension? (c) Are there regional variations in the monotonic and fatigue properties ...
Serial measurement of peripheral oestrogen and progesterone concentrations in oestrous mares to determine optimum mating time and diagnose ovulation. Rapid enzyme-based immunoassays were used to measure concentrations of oestradiol-17 beta and progesterone in daily blood samples recovered throughout oestrus and for a few days after ovulation from 34 Thoroughbred and 8 pony-type maiden, barren and foaling mares. The first detectable fall in oestradiol-17 beta levels occurred in 88% of the mares within the interval -72 to 0 h with respect to ovulation and in 65% of mares within the interval of -48 to 0 h. The results indicated that serial daily hormone assays of this type could, in a high proportion of animals, predict a correct time for a si...
Thermal and cardiorespiratory responses of horses to submaximal exercise under hot and humid conditions. The objective of this study is to determine the effects of heat, and heat and high relative humidity (RH) on the thermal and cardiorespiratory responses to exercise and recovery. Five Thoroughbred horses (age 3 to 6) completed exercise tests under each of 3 environmental conditions: cool, dry (CD, room temperature (T) = 20 degrees C, RH = 45-55%), hot, dry (HD, T = 32-34 degrees C, RH = 45-55%) and hot, humid (HH, T = 32-34 degrees C, RH = 80-85%). Horses were exercised at a workload equal to 50% of VO2max on a treadmill set at a 10% slope until attainment of a pulmonary artery blood (PA) temp...
Distribution of cytosolic oestrogen and progesterone receptors in the genital tract of the mare. The distribution of oestrogen and progesterone receptors in the equine genital tract was investigated by means of a modified dextran-coated charcoal method on samples collected from the vagina, the cervix and the uterus of 30 healthy adult Polish mares, divided into two groups on the basis of their serum progesterone levels. The concentrations of oestrogen and progesterone receptors were significantly (P < 0.05) lower in the vagina and the cervix than in the uterus, in agreement with data from human beings, cattle and pigs, which showed that the highest concentrations of oestrogen and proge...
Effects of gonadal steroids on the opioid regulation of LH and prolactin release in ovariectomized pony mares. The aim of the present study was to investigate the role of ovarian steroids in the opioid regulation of LH and prolactin release in mares. Effects of the opioid antagonist naloxone on LH and prolactin secretion were determined in ovariectomized pony mares. The animals were pretreated with either progesterone (500 micrograms kg-1) or oestradiol benzoate (10 micrograms kg-1) for 8 days and subsequently with a combination of progesterone and oestradiol for an additional 8 days. Naloxone administration (0.5 mg kg-1 i.v.) resulted in a significant release of LH as well as prolactin in mares after ...
Ultrasound-guided intrafollicular treatment in mares. A technique for intrafollicular treatment with a transvaginal ultrasound-guided injection needle was developed using equine chorionic gonadotropin (eCG) as the test substance. An injection was made into one growing follicle of a wave when the follicles were 20 to 23 mm. The treated follicles were injected with 1000 iu of eCG in 0.2 ml saline solution and control follicles were injected with 0.2 ml of the saline vehicle (10 mares per group, 1 follicle per mare). The injection system used an inner 25-gauge needle and an outer 20-gauge needle inserted together through the needle-guide channel of ...
