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.
Effects of dihydrotestosterone administration with and without estradiol pretreatment on gonadotropin secretion in ovariectomized pony mares. Twenty ovariectomized pony mares were used to determine if dihydrotestosterone propionate (DHTP) administration, with or without estradiol benzoate (EB) pretreatment, would have the same effects on follicle stimulating hormone (FSH) and luteinizing hormone (LH) secretion as testosterone propionate (TP) administration. All mares were given an initial injection of gonadotropin releasing hormone (GnRH) to characterize their LH and FSH response, and then two groups of mares (n = 4/group) were administered EB (22 micrograms/kg of body weight), two groups were administered vehicle (safflower oil) an...
Immune-mediated hemolytic anemia induced by penicillin in horses. Three horses developed severe, immune-mediated hemolytic anemia after treatment with penicillin. The horses had positive direct antiglobulin (Coombs) tests and high titers of IgG antibody that agglutinated penicillin-coated equine red cells. Two of the horses were tested for antibodies to autologous red cell antigens; autoantibodies were not present. Titers of antipenicillin antibody decreased after penicillin was discontinued but IgG antibody was detectable months after recovery. One of the horses was challenged with penicillin; antibody titer increased slightly, but anemia did not develop. A...
Isolation of Cache Valley virus and detection of antibody for selected arboviruses in Michigan horses in 1980. Blood samples collected in September and November 1980 from 87 horses in southwestern Michigan were examined for virus isolation and for plaque-reduction neutralizing antibody against selected arboviruses. Cache Valley virus was isolated from the blood of a clinically normal horse in St Joseph County in September. The age-specific antibody prevalence for Cache Valley virus indicated enzootic transmission in the study area. The high antibody prevalence and the lack of age-specific antibody prevalence indicated sporadic, but intense, exposure to Jamestown Canyon virus. Low prevalences of antibod...
Experimental Trichinella infections in ponies. Light Trichinella infections were established in three ponies given 1000, 5000 and 25000 T. spiralis spiralis infective larvae respectively by stomach tube. A predilection site of infection in all ponies was the tongue. Anti-Trichinella antibodies were detected in all ponies by the enzyme-linked immunosorbent assay using a T. spiralis spiralis excretory-secretory antigen. The ponies given 5000 and 25000 infective larvae reacted positively on days 26 and 24 postinfection, respectively, using a criterion of greater than or equal to 5 X mean optical density readings of preinfection sera as positi...
Unilateral phalangeal dysgenesis and navicular bone agenesis in a foal. This research journal article documents a rare case of a five-day-old foal suffering from a congenitally malformed hoof and the associated lameness. The disorders studied were unilateral navicular bone agenesis […]
Vesicular exanthema of swine virus: isolation and serotyping of field samples. Virus isolation was attempted from 262 field samples of vesicular material collected during the outbreaks of vesicular exanthema of swine in the U.S.A. from 1952-54. Using primary swine kidney culture, viral cytopathogenic agents were isolated from 76.3% of the samples. However, an overall recovery rate of 82.1% was obtained after samples negative in tissue culture were inoculated intradermally in susceptible swine. All vesicular exanthema of swine virus isolates were identified as serotype B51 using complement fixation and serum neutralization tests. Two isolates did not react with antisera t...
Structural studies on equine glycoprotein hormones. Amino acid sequence of equine lutropin beta-subunit. The amino acid sequence was determined for equine lutropin beta (eLH beta). Large fragments were derived from reduced, carboxymethylated eLH beta by digestion with Staphylococcus aureus V8 protease, by cyanogen bromide cleavage, and by cleavage of acid-labile Asp-Pro bonds. The fragments were purified by gel filtration and high performance liquid chromatography (HPLC). The fragments were sequenced by automated Edman degradation to establish the primary structure of eLH beta. Some peptides were further digested with chymotrypsin and the resulting peptides purified by HPLC. In addition to sequen...
Structural studies on equine glycoprotein hormones. Amino acid sequence of equine chorionic gonadotropin beta-subunit. The complete amino acid sequence of the beta-subunit of equine chorionic gonadotropin (eCG beta) has been established by both automated Edman and manual 5-dimethylaminonaphthalene-1-sulfonyl-Edman degradations. Specific fragments were produced by cleavage with Staphylococcus aureus V8 protease, trypsin, or dilute HCl. For the sequence analyses of the heavily glycosylated COOH-terminal portion, a chemical deglycosylation procedure with trifluoromethanesulfonic acid was employed. The peptide chain of eCG beta consists of 149 amino acid residues. Five or more oligosaccharide chains are attached t...
Calmodulin-mediated adenylate cyclase from mammalian sperm. Calmodulin (CaM), the calcium binding protein that modulates the activity of a number of key regulatory enzymes, is present at high levels in sperm. To determine whether CaM regulates adenylate cyclase in mammalian sperm, the actions of EGTA and selected CaM antagonists on a solubilized adenylate cyclase from mature equine sperm were examined. The activity of equine sperm adenylate cyclase was inhibited by EGTA in a concentration-dependent manner with a half-maximal inhibitory concentration (IC50) of 2 mM. Equine sperm adenylate cyclase was also inhibited in a concentration-dependent manner by...
Isolation and characterization of two protamines St1 and St2 from stallion spermatozoa, and amino-acid sequence of the major protamine St1. Two protamines, St1 and St2, were isolated from stallion sperm nuclei, where they represent about 75 and 25%, respectively, of the total basic protein complement. The primary structure of protamine St1 (49 residues; Mr approximately equal to 6600) has been determined. The structure of this protamine is compared to the amino-acid sequence of other mammalian protamines already known.
Cellulitis and subcutaneous abscesses caused by Rhodococcus equi infection in a foal. Cellulitis and subcutaneous abscess formation was diagnosed in a 3-month-old Thoroughbred filly. Clinical signs consisted of a large ulcerated plaque, with satellite pustules on the medial aspect of the right hock and subcutaneous abscesses in the right inguinal and mammary gland areas. Laboratory analysis revealed mature neutrophilia. Rhodococcus equi was isolated from the cellulitis and the subcutaneous abscess. Oral administration of erythromycin and rifampin for 35 days resulted in a clinical cure.
Evaluation of fenbendazole for larvacidal effect in experimentally induced Parascaris equorum infections in pony foals. Fifteen pony foals were inoculated with 1,500 +/- 298.7 infective Parascaris equorum eggs. The foals were assigned to 3 treatment groups. Treatments included 10 mg of fenbendazole/kg given once on postinoculation day (PID) 11, 10 mg of fenbendazole/kg given daily on PID 11 to 15, and no treatment (controls). The foals were euthanatized on PID 25 and examined for P equorum larvae in the small intestine, lungs, and liver. Significantly (P less than 0.05) lower mean numbers of P equorum larvae were found in the small intestine of foals treated on PID 11 to 15 (1.4 [range, 0 to 6]) than in the sma...
Pulmonary aspergillosis in a horse with myelomonocytic leukemia. Acute myelomonocytic leukemia was diagnosed in a 2-year-old Standardbred mare that had hind limb edema and fever unresponsive to antibiotics. The mare had anemia, thrombocytopenia, and leukocytosis, with circulating myeloblasts and monocytoid cells. A bone marrow specimen was hypercellular, with myeloblasts and monocytoid cells. Peroxidase, chloroacetate esterase, and alpha naphthyl acetate esterase activities were detected in many bone marrow cells. Interstitial pulmonary densities were seen radiographically. The mare was euthanatized and necropsied. Infiltrates of leukemic cells were found m...
Pleuroscopic diagnosis of gastroesophageal squamous cell carcinoma in a horse. A 15-year-old Quarter Horse gelding was examined because of chronic intermittent colic of 40 days' duration. The clinical signs included acute onset of depression, ptyalism, abdominal splinting, and rolling within an hour of eating. An intramural mass of the esophagus was identified during esophagoscopy. A large soft-tissue density surrounding the distal portion of the esophagus, creating a stricture, was identified on an esophagogram. With the horse slightly sedated, pleuroscopy was performed, allowing direct visualization and biopsy of the mass. The histopathologic diagnosis was squamous cel...
Atrial fibrillation in a pregnant mare: treatment with quinidine sulfate. Atrial fibrillation in a pregnant, lactating, 15-year-old mare nursing a 70-day-old foal was converted to normal sinus rhythm, using quinidine sulfate. The maximum concentration of quinidine was 4.3 mg/L in the mare's milk and was 2.6 mg/L in the mare's serum. Treatment with quinidine did not interrupt the pregnancy. Six months after treatment, the mare developed acute volvulus of the large colon and died. At necropsy, the mare did not have macroscopic or microscopic cardiac lesions. The fetus was macroscopically and histologically normal.
Scanning electron microscope observations of hoof horn from horses with brittle feet. Two types of defect were observed when hoof clippings from horses with brittle feet were viewed in the scanning electron microscope. The first defect showed a loss of structure and horn in the stratum externum. This defect was remedied after biotin treatment. The second defect showed poor attachment of the horn squames and failed to respond to biotin treatment alone. An improvement in this case was achieved by the addition of powdered limestone to the diet.
Clinical observations on the use of BCG cell wall fraction for treatment of periocular and other equine sarcoids. Clinical observations on the use of BCG cell wall fraction in oil for treating seven horses with periocular sarcoids and five horses with sarcoids in other regions are described. Therapy was successful when used for periocular or solitary and smaller sarcoids. For sarcoids previously treated with cryosurgery, therapy appeared to be less efficient. A horse with a sarcoid on the stifle developed a septic gonitis due to necrosis of the sarcoid tissue adjacent to the joint. Sarcoids of the axilla appeared to be more aggressive than sarcoids at other locations and did not respond favourably to this...
Left ventricular hypertrophy in chronically hypertensive ponies. Systemic arterial hypertension is associated with equine laminitis, a disease precipitated by gross over-ingestion of carbohydrates. We examined the hearts from nine chronically hypertensive (161 +/- 11/99 +/- 6 mmHg) laminitic ponies and nine normotensive (128 +/- 2/76 +/- 3 mmHg) ponies postmortem for signs of left ventricular hypertrophy. The hypertensive ponies had hearts which were significantly larger (7.77 +/- 0.26 g/kg bodyweight (BW) vs. 5.67 +/- 0.22 g/kg BW), as well as increased combined left ventricle and septum weight (4.99 +/- 0.21 g/kg BW vs. 3.67 +/- 0.20 g/kg BW) and left ven...
Actions of non-steroidal anti-inflammatory drugs on equine leucocyte movement in vitro. The direct effects of four non-steroidal anti-inflammatory drugs (NSAIDs) on equine polymorphonuclear (PMN) and mononuclear (MN) leucocyte movement were investigated using two in vitro assay systems. The Boyden chamber microfilter technique measures both chemokinetic and chemotactic locomotion, and the agarose microdroplet assay measures solely chemokinesis. Zymosan-activated plasma (ZAP) and the synthetic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) were used as standard chemoattractants for PMN and MN leucocytes, respectively. The actions of six concentrations of each NSAID, indome...
Thoroughbred blood serum inorganic phosphate concentrations in relation to feeding regime and racing performance. Horses receiving a pelleted or cubed dietary supplementation with roughage, have serum inorganic phosphate (SIP) concentrations consistently below an accepted mean of 1,032 mmol l-1 or 3, 1 mg dl-1. Further, it has been reported that the best eight, two-year-old Irish Thoroughbred track performers of 51 horses tested over a 10 month period, had significantly lower SIP concentrations than the worst eight track performers. In an endeavour to assess any nutritive effect on SIP concentrations and also to assess any effect of SIP concentrations on track performance, metabolic blood profiles from 30...
The induction of equine laminitis with an aqueous extract of the heartwood of black walnut (Juglans nigra). An aqueous extract of the heartwood of black walnut (Juglans nigra) was given via stomach tube to 10 horses. Eight developed Obel grade 3 or 4 laminitis within 12 hr. Limb edema and mild sedation were the only other clinical signs observed. One horse was euthanized due to severe signs. The other 7 recovered within 6 days. Gas chromatography/mass spectrometry of aqueous extracts of heartwood, bark and nuts of black walnut identified juglone in the bark and nuts, but not in the heartwood. It was concluded that the aqueous extract of heartwood is laminogenic to horses, but the active ingredient i...
[Testing of a deworming scheme for horses]. In 1983 and 1984 the effect of a deworming scheme, in which horses were treated at turn out and 4 and 8 weeks later, on the egg output, larval differentiation, weight gain, herbage infestation and in 1984, the percentages of some serum proteins were tested. In 1983 the experiment was done with 42 mares, 54 two year old male horses and 42 male yearlings, kept in groups with permanent or rotational grazing. In 1984 only 90 male yearlings were investigated. In 1983 albendazole and ivermectin were used, 1984 ivermectin. The results of the faecal examinations showed that after ivermectin treatment ...
Pythium destruens sp. nov., an agent of equine pythiosis. The equine phycomycotic agent known commonly as Hyphomyces destruens or occasionally as Pythium gracile, is described as a new species Pythium destruens. Separation is on the basis of morphological features, temperature growth profiles, esterase/lipase activity, and carbohydrate utilization ability. P. diclinum (synonymous with P. gracile sensu Middleton) showed minor differences in vesicle, oospore and oogonium size from P. destruens. P. destruens grew at 40 degrees C on corn meal agar and hydrolysed esters of lauric and oleic acids. These abilities were not displayed by P. diclinum, but this...
Transmural coronary vasodilator reserve and flow distribution during maximal exercise in normal and splenectomized ponies. 1. Transmural distribution of myocardial blood flow was studied using 15 micron diameter radionuclide-labelled microspheres in six normal ponies and nine splenectomized ponies at rest, and during maximal exercise performed without as well as with adenosine infusion (3 microM kg-1 min-1). The splenectomized ponies were also studied during submaximal exercise performed at 75% of the workload. 2. Maximal exertion in normal ponies increased heart rate (348%), mean arterial blood pressure (40.9%), rate-pressure product (563%), arterial O2 content (43.2%), and mean pulmonary artery pressure (247%). ...
