Ponies are members of the Equidae family and share many physiological and anatomical characteristics, yet they are distinguished by several key differences. Ponies are generally smaller in stature, with a height at the withers of 14.2 hands (58 inches) or less, while horses exceed this height. In addition to size, ponies often exhibit a stockier build, thicker manes, tails, and coats, and a greater bone density compared to horses. These differences can influence their suitability for various tasks and environments. This topic encompasses a collection of peer-reviewed research studies and scholarly articles that explore the genetic, phenotypic, and behavioral distinctions between ponies and horses, as well as their implications for breeding, management, and performance in equine disciplines.
Klei TR, Torbert BJ, Chapman MR, Turk MA.A controlled test method was used to evaluate the efficacy of injectable micelle and oral paste formulations of ivermectin (22,23-dihydroavermectin B1) against 8-week-old Strongylus vulgaris larvae in experimentally infected pony foals. The dosage level of the drug in both formulations tested was 0.2 mg/kg. Ponies were euthanatized and necropsied 5 weeks after treatment. Based on the recovery of live vs dead S vulgaris from mesenteric arteries, both formulations were greater than 99% effective. Increased weight gains and marked reductions in the severity of arterial lesions were observed in tr...
Dyer RM, Liggitt HD, Leid RW.A device was constructed from an equine nasogastric tube, polyethylene tubing, and a 3-way stopcock and used to lavage the lungs of anesthetized ponies. The technique was safe and atraumatic in that 6.4 to 19.7 X 10(7) purified alveolar macrophages were removed from the lungs without harm to the ponies or contamination of the samples with blood. Studies of these highly purified cell suspensions revealed a mean viability of 85% as assessed by eosin dye exclusion with a mean recovery (+/- SD) of 12.5 +/- 4.8 X 10(7) pulmonary alveolar macrophages/pony.
Wagerle LC, Orr JA, Shirer HW, Kiorpes AL, Fraser DB, DeSoignie RC.The purpose of these studies was to examine the time course of the cerebrovascular response to acute hypoxia in unanesthetized ponies. An electromagnetic flow transducer chronically placed on the internal carotid artery of the pony allowed continuous recording of internal carotid artery blood flow (ICBF) which has been shown to be representative of cerebral blood flow (CBF). The ponies were subjected to three levels of acute isocapnic hypoxia (PaO2 = 62, 44, and 39 mm Hg for hypoxia level I, II, and III, respectively), and the temporal and steady-state cerebrovascular response was examined. IC...
Hildebrand SV, Howitt GA.Succinylcholine was administered by infusion to halothane-anesthetized ponies to determine dosage requirements for surgical relaxation up to 3 hours' duration. This was not possible to do, since 4 of 6 ponies studied developed severe reactions characterized by prolonged muscle fasciculations after the initial succinylcholine dose, muscle rigidity, hyperthermia, hypercapnia, tachycardia, increasing pulse pressure, and metabolic acidosis. The reactions resembled those associated with malignant hyperthermia, a disease recognized in persons and swine. Two ponies showed signs of the phase II or des...
Slocombe JO, McCraw BM, Pennock PW, Baird JD.Twelve pony foals (reared worm-free) were inoculated with Strongylus vulgaris. Approximately 8 weeks later, 4 of the foals were given fenbendazole (10% suspension) at a dosage rate of 10 mg/kg of body weight daily for 5 days and 4 foals were given the suspension at a dosage rate of 50 mg/kg daily for 3 days; the remaining foals were given a placebo. All treatments were administered by stomach tube. Fenbendazole was 99.6 and 97.9% effective in the 2 treatment groups, respectively, in eliminating later 4th-stage S vulgaris larvae located near the origin of major intestinal arteries. On microscop...
Suann CJ, Horney FD.Circumcision (or reefing operation) was performed on an aged pony stallion to remove excessive granulation tissue involving the preputial integument following an injury and subsequent paraphimosis. Postoperative swelling of the penis and prepuce was reduced daily with gentle massage. Initially, an improvised suspensory was used to support the penis postoperatively. The pony was able to voluntarily retract its penis six months following surgery.
Bortell R, Asquith RL, Edds GT, Simpson CF, Aller WW.Nineteen weanling ponies and 1 adult pony were given a single oral dose of aflatoxin B1 (AFB1). Dosages were: 0, 0.5, 1, 2, 4, 5, 6, and 7.4 mg of AFB1/kg of body weight. Vital signs were monitored, and whole blood and serum collected for analysis of serum enzymes, prothrombin time, blood cell counts, and serum urea nitrogen. Ponies that died were examined for gross lesions, and tissues were collected for histopathologic examination and analysis of AFB1 and AFM1 residues. Two of the 4 ponies given the 2 mg/kg dose and all ponies given the larger dosages died within 76 hours. Clinical signs inc...
Stick JA, Slocombe RF, Derksen FJ, Scott EA.Esophageal healing was studied in 12 ponies after cervical esophagotomy. The esophagus was sutured, feed and water were withheld for 48 hours, and then all ponies were permitted to eat. In group I (n = 6), a longitudinal esophagotomy was made. In group II (n = 6), a rotational esophagotomy was made with the mucosal incision 180 degrees away from the incision in the esophageal muscle. Three ponies in each group were fed a soft diet ad libitum for 9 days, and then were allowed access to hay and grain. The remaining ponies were fed hay and grain. The esophagotomies of all hay-fed ponies dehisced ...
White NA, Moore JN, Douglas M.This paper describes the histological and scanning electron microscopical examinations of the right colic artery of eight ponies. Lesions all had large thrombi surrounding a larva or larvae, with arterial wall thickening. Endothelial shape change, degeneration and loss were present. Fibrin-platelet red blood cell aggregates were present on endothelial surfaces as well as on the surface of thrombi. Damage to the intima appeared to produce the conditions for progressive thrombus formation.
Stalheim OH, Cottew GS, Freundt EA, Koski TA, Leach RH, Perreau P, Stone SS.Antisera to 10 mycoplasma species of bovine origin were produced in 10 ponies and were distributed for evaluation in growth-inhibition tests at 6 laboratories in Australia, England, Denmark, France, and the United States. Except for a few failures with some antigens produced at the 6 laboratories, the antisera induced large zones of growth inhibition in homologous, but not heterologous, systems. These antisera may be useful as standard reagents for the identification of the bovine mycoplasmas.
Srivastava SK, Barnum DA.Streptococcus equi was found to adhere to tongue, cheek and nasal epithelial cells of ponies, in vitro. Maximum adherence was observed at pH 7.5 after one hour of incubation of bacteria with epithelial cells. This adherence was more on epithelial cells from adult animals than from foals. Streptococci exposed to heat (60 degrees C for 10 min) or treated with pepsin or trypsin showed a reduced adherence, whereas an increase occurred on treatment with hyaluronidase. Antibodies against whole S. equi cells or M-like protein blocked the adherence, whereas antibodies against group-specific carbohydra...
Hofing GL, Bennett DG.Patent infections with Strongylus vulgaris were established in 6 of 8 helminth-free ponies given 41 to 101 adult worms via nasogastric tube. The parasites were removed from the cecum and ventral colon and transferred within 1 to 2 hours of the death of the donor horses. Eggs were found in the feces of the recipients in 2 or 3 days; egg counts reached maximum, 28 eggs per gram of feces, at 4 weeks after ponies were inoculated. In 6 ponies euthanatized 3 to 7 weeks after parasitic transfers were done, 28% of the inoculated worms were found alive at necropsy. A 7th pony was maintained as a donor ...
Parks CM, Manohar M.Blood flow to the brain, heart, kidneys, diaphragm, and skeletal muscles was studied at rest and during graded treadmill exercise, using radionuclide-labeled microspheres (15 microns diameter), in 11 healthy adult ponies. Hemodynamic changes brought about by exercise included marked increases in cardiac output, mean aortic pressure, left ventricular end-diastolic pressure, and right ventricular systolic and end-diastolic pressures. Blood flow to the brain stem and cerebral hemispheres was unchanged during both moderate exercise (heart rate = 154 +/- 3 beats/min) and severe exercise (heart rate...
Ralston SL, Freeman DE, Baile CA.The roles of volatile fatty acids (VFA) and of the large intestine in the control of feeding in ponies were investigated. Ponies with cecal fistulas were adapted to ad libitum access to pelleted feed. Treatment solutions were given as a bolus 15 min before the animals were allowed free access to feed after a 4-h fast. Each dose of VFA solution was tested in a crossover design with a water control. When the ponies were permitted to eat after the treatments, the latency to eat, first meal size, and duration and first intermeal interval were recorded. Feed intakes were measured at 3 and 18 h afte...
Withrow JM, Sargent GF, Scheffrahn NS, Kesler DJ.Two pony mares were administered 150 mg of testosterone propionate every other day for 20 days (ten injections) and every ten days there-after. An additional two mares and one stallion were not treated and served as controls. Testosterone propionate was dissolved in absolute ethanol and administered subcutaneously. Sex behavior tests were conducted 26 and 40 days after the first injection. Control mares exhibited very little male sex behavior. Both testosterone propionatetreated mares, however, exhibited mounting, sniffing, flehmen, biting and vocalization behavior in the presence of an estrou...
Blythe LL, Kitchell RL, Holliday TA, Johnson RD.Normal nerve conduction velocity values in 10 ponies were determined for sensory nerve fibers in the median and ulnar nerves. A percutaneous signal-averaging technique was developed and used. Medial and lateral palmar digital nerves on the abaxial surface of the proximal sesamoid bones were used as the sites for percutaneous stimulation, whereas recording sites included the medial and lateral palmar nerves just distal to the carpus and the median and ulnar nerves in the middle of the radius. Sensory nerve conduction velocities can be evaluated simply and clinically in the limbs of horses, usin...
Parks C, Manohar M, Lundeen G.To examine the effects of tachycardia on coronary circulation, transmural distribution of myocardial blood flow (MBF, 15-micron diameter radionuclide-labeled microspheres) was studied in six healthy adult ponies at rest (heart rate = 60 +/- 7 beats . min-1), during ventricular pacing at 150 and 200 beats . min-1, as well as with ventricular pacing at 250 beats . min-1 before and during maximal coronary vasodilatation (iv adenosine infusion; 4 mumole . kg-1 . min-1). Mean aortic pressure and cardiac output were unchanged from control values with ventricular pacing. Whereas ventricular pacing at...
Reitsma JF.A report on infection with Dictyocaulus arnfieldi in a number of ponies and one horse in which complete clinical recovery was obtained following treatment with albendazole (Valbazen), administered by oral route at a dosage of 25 mg/kg of body weight twice daily for five days.
Tate LP, Ralston SL, Koch CM, Everitt JI.Small intestinal resection (SIR) is not uncommonly done in surgical treatment of equine colic, but little is known about the long-term effects of SIR on horses and ponies. Twelve ponies, fed maintenance amounts of pelleted feed, were divided randomly into 4 treatment groups. D-Xylose absorption curves were recorded for each pony before surgical treatments were performed. Treatments consisted of control (ileal bypass) and 40%, 60%, or 80% SIR. D-Xylose absorption, serum electrolyte, and enzyme profiles for each animal were recorded once every 30 days for 180 days after surgical treatment, and t...
Coffman JR, Colles CM.Sensitivity to insulin was assessed in ponies episodically affected with chronic laminitis by measurement of blood glucose and arterial blood pressure during insulin tolerance tests. In terms of blood glucose values, laminitic ponies were significantly less sensitive to insulin than controls. Conversely, a post-insulin decline in diastolic, systolic and mean blood pressure values was significantly greater in laminitic ponies than in controls.
Makawiti DW, Allen WE, Kilpatrick MJ.A simple and rapid (less than 2 h) immunoassay method has been developed based upon a novel separation technique called LIDIA (Ligand Differentiation Immunoassay), enabling direct estimation of the concentration of oestrone sulphate in ethanolic extracts of blood plasma. An antiserum raised against oestrone-3-glucuronyl-BSA was used which showed a higher cross-reaction with the sulphate than the glucuronide metabolite. The assay had a sensitivity of 5.2 pg/tube and acceptable inter-(less than 18%) and intra-(less than 8.5%) assay precision. Analysis of samples of peripheral venous plasma obtai...
Blanchard TL, Elmore RG, Youngquist RS, Loch WE, Hardin DK, Bierschwal CJ, Ganjam VK, Balke JM, Ellersieck MR, Dawson LJ, Miner WS.Fifty mature pony stallions were randomly assigned to one of five treatment groups: Group 1- controls (no treatment), Group 2 - 0.55 mg/kg stanozolol weekly for 13 treatments, Group 3 - 1.1 mg/kg stanozolol every 3 weeks for 5 treatments, Group 4 - 1.1 mg/kg boldenone undecylenate every 3 weeks for 5 treatments, and Group 5 - 0.55 mg/kg boldenone undecylenate weekly for 13 treatments. Scrotal widths (SW), combined testis weights (CTW), and daily sperm productions (DSP) were not different between Groups 1 and 2. Ponies in Group 5 had smaller SW (P<0.01), smaller CTW and decreased DSP compare...
Harkema JR, Robinson NE, Scott JB.Twelve Shetland ponies were fed a high-starch ration. Seven ponies which had a transitory metabolic acidosis developed laminitis 56 hours (+/- 3.5, SEM) after overfeeding. These ponies also developed persistent hypokalemia, hyperthermia, and increased heart rate 24 hours before the onset of lameness. Serum sodium, serum chloride, hematocrit, plasma volume, and blood volume were unchanged. At the onset of clinical signs of laminitis, cardiac output and blood pressure increased, but total peripheral resistance was unchanged. None of the measured or calculated values predicted the onset of lamini...
Greer GJ, Bello TR, Amborski GF.ABSTRACT: The prepatent period of Strongyloideswesteri experimentalinfection in ponies was 6 to 10 days in pony foals and 11 to 13 days in pony yearlings. The infection stimulated moderate inflamma- tion in the anterior one-third of the small intestine in pony foals. Pony yearlings and Quarter Horse foals lost the infection and were resistantto reinfection. The loss of infection was associated with a neutrophiliain QuarterHorse foals and an increase in p-globulin in pony yearlings.
Ghoshal NG.A relatively unknown existence of a tracheal bronchus in three, approximately 2-3 years old ponies, is reported and the possible genesis of this anomaly is discussed.
Frauenfelder HC, Fessler JF, Latshaw HS, Moore AB, Bottoms GD.External cardiac massage and concomitant respiratory support were used successfully 6 of 8 anesthetized ponies sustaining unexpected cardiac arrest while being used in a study of shock. Approximately 20 thoracic compressions/min maintained systolic and diastolic aortic blood pressures in excess of 50% of the corresponding base-line values in 5 ponies. The high success rate was attributed to early recognition of the problem, the small size of the patient, and the relatively short duration of cardiopulmonary resuscitation (average, 2.9 minutes). It was concluded that external cardiac message can...
Haluska GJ, Lowe JE, Currie WB.A complete set of electromyographic recordings, plasma samples and behavioural observations were collected from 2 mares beginning 7 days pre partum, through parturition and into the early post-partum period. During the week pre partum, EMG activity was elevated, occurring 26-73% of the time. Activity was least during the day and greatest at night with no significant difference for the hours of the day or between days pre partum. During the 24 h before delivery, EMG activity was increased for 7-13 h (55-80%) during the daylight hours. EMG activity decreased 2-4 h immediately preceding delivery ...
Cullen CL, Grahn BH.The study reports on the diagnosis and treatment of a severe case of corneal ulceration and anterior uveitis in a 1-year-old Norwegian fjord pony, which did not respond to initial […]
Gibson K, O'Hara A, Huxtable C.Focal intramural nodules were palpated in the rectal wall of a 12-year-old pony mare presented for rectal prolapse. Eosinophilic proctitis was diagnosed by examination of fine needle aspirates and biopsy of the largest rectal nodule. After treatment with a course of corticosteroids, the rectal nodule and accompanying peripheral eosinophilia resolved. There was no recurrence of the condition during the follow-up period of 20 months. Focal eosinophilic proctitis appeared to be an unusual cause of tenesmus and rectal prolapse in this case.
Reilly JD, Cottrell DF, Martin RJ, Cí·¯ord DJ.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 ...