Shetland Ponies are a distinct category within the equine species with unique characteristics and uses. Shetland Ponies are a small, hardy breed originating from the Shetland Islands in Scotland, known for their strength, intelligence, and adaptability to harsh climates. This topic explores the comparative anatomy, physiology, and behavioral traits of Shetland Ponies, as well as their respective roles in equestrian activities and agriculture. Included are peer-reviewed research studies and scholarly articles that investigate genetic, nutritional, and health aspects specific to each group, providing insights into their care and management.
Dupont S, De Spiegeleer A, Liu DJ, Lefère L, van Doorn DA, Hesta M.Commercial immunoglobulin E (IgE)-based tests are available for diagnosis of food allergies and are commonly used in equine practice. However, these tests have been proven unreliable as a screening method in man and other species, but not critically evaluated in equids. Therefore, a commercially available IgE-based test for horses was evaluated. Objective: To evaluate the consistency of the results obtained with a commercially available IgE-based test for food allergy diagnosis in ponies (Phase I) and to subject ponies to a provocation trial with the presumed allergens (Phase II). Methods: All...
Brinkmann L, Gerken M, Hambly C, Speakman JR, Riek A.Recent results suggest that wild Northern herbivores reduce their metabolism during times of low ambient temperature and food shortage in order to reduce their energetic needs. It is, however, not known whether domesticated animals are also able to reduce their energy expenditure. We exposed 10 Shetland pony mares to different environmental conditions (summer and winter) and to two food quantities (60% and 100% of maintenance energy requirement) during low winter temperatures to examine energetic and behavioural responses. In summer, ponies showed a considerably higher field metabolic rate (FM...
Bruynsteen L, Janssens GP, Harris PA, Duchateau L, Valle E, Odetti P, Vandevelde K, Buyse J, Hesta M.The present study evaluated the effect of different levels of energy restriction on metabolic parameters in obese ponies. Relative weight changes, markers of lipid metabolism and oxidant/antioxidant balance were monitored. A total of eighteen obese (body condition score ≥ 7/9) Shetland ponies were studied over a 23·5-week trial, which was divided into three periods. The first period involved a 4-week adaptation period in which each animal was fed 100% of their maintenance energy requirements needed to maintain a stable obese body weight (MERob). This was followed by a 16·5-week weight-loss...
Gabor V, Gerken M.Numerical competence is one of the aspects of animal cognition with a long history of research interest, but few results are available for the horse. In the present study, we investigated the ability of three Shetland ponies to discriminate between different quantities of geometric symbols presented on a computer screen in a matching-to-sample arrangement. In Experiment 1, the ponies had to relate two similar quantities to another, paired in contrasts (1 vs. 2, 3 vs. 4 and 4 vs. 5) of the same stimulus (dot). Specific pairs of quantities (all differing by one) of up to five different geometric...
Schurink A, van der Meide NM, Savelkoul HF, Ducro BJ, Tijhaar E.Insect bite hypersensitivity (IBH) is a common allergic skin disease in horses, caused by biting insects of the Culicoides spp. In The Netherlands, Culicoides spp. of the Obsoletus complex are the most important midges involved in IBH. The aim of the present study was to identify and quantify associations between several endogenous (host) and exogenous (environmental) factors and immunoglobulin E (IgE) reactivity against Obsoletus complex-derived whole body extract or seven recombinant allergens, measured by ELISA. Data from 143 Icelandic horses and 177 Shetland ponies were analysed using mult...
Brinkmann L, Gerken M, Riek A.Water is an essential nutrient necessary to support life, and adequate water supply is crucial for animal survival and productivity. The present study was designed to determine seasonal changes in the water metabolism of horses under outdoor conditions. Total body water (TBW) and total water intake (TWI) of 10 adult Shetland pony mares were estimated at monthly intervals for 14 mo by using the deuterium dilution technique. During the last 4 mo, 5 ponies were fed restrictively to simulate natural feed shortage in winter, and 5 ponies served as controls. The TBW (kg) was closely related to body ...
Meulenbroeks C, van der Meide NM, Zaiss DM, van Oldruitenborgh-Oosterbaan MM, van der Lugt JJ, Smak J, Rutten VP, Willemse T.Insect bite hypersensitivity (IBH) in horses is a seasonal, IgE-mediated, pruritic skin disorder primarily caused by Culicoides spp. We hypothesize that a mixed Th2/Th1-type immune status, off season, alters into Th2-dominated immune reactivity in the skin of IBH-affected ponies in the IBH season. To study these immune response patterns Culicoides-specific IgE levels, skin histopathology and cytokine and transcription factor mRNA expression (IL4, IL10, IL13, IFNγ, FoxP3 and CD3(ζ)) in lesional and non-lesional skin of ponies affected by IBH in the IBH season were compared with those of the s...
Brinkmann L, Gerken M, Riek A.Outdoor group housing is increasingly recognized as an appropriate housing system for domesticated horses. The objective of this study was therefore to investigate the effect of potential feed shortage in semi-natural horse keeping systems in winter on animal health and welfare. In 10 female Shetland ponies blood concentrations (NEFA, total protein (TP), total bilirubin (TB), beta-hydroxybutyrate (BHB) and thyroxine (T4)), body mass and the body condition score (BCS) were monitored for 7 months including a 4 months period of feed restriction in five of the 10 ponies. Restrictively fed animals ...
Schurink A, Wolc A, Ducro BJ, Frankena K, Garrick DJ, Dekkers JC, van Arendonk JA.Insect bite hypersensitivity is a common allergic disease in horse populations worldwide. Insect bite hypersensitivity is affected by both environmental and genetic factors. However, little is known about genes contributing to the genetic variance associated with insect bite hypersensitivity. Therefore, the aim of our study was to identify and quantify genomic associations with insect bite hypersensitivity in Shetland pony mares and Icelandic horses in the Netherlands. Methods: Data on 200 Shetland pony mares and 146 Icelandic horses were collected according to a matched case-control design. C...
Ambrisko TD, Coppens P, Kabes R, Moens Y.This study compares cardiac output (CO) measurements obtained by lithium dilution (LiDCO), pulse power analysis (PulseCO), and continuous thermodilution (CTD) with bolus thermodilution (BTD) in ponies. Methods: Eight isoflurane-anaesthetized Shetland ponies received xylazine, ketamine, and midazolam infusions (0.3, 1.2, and 0.018 mg kg(-1) h(-1), respectively). CO was measured with BTD, CTD, LiDCO, and PulseCO. Lithium was injected into the jugular vein and blood was sampled from the facial artery for lithium detection and this artery was also used for PulseCO. Measurements were obtained durin...
Schurink A, Podesta SC, Ducro BJ, van Arendonk JA, Frankena K.Insect bite hypersensitivity (IBH) is an equine skin allergy caused by bites of Culicoides spp. and impacts on the welfare of affected horses. The aim of this study was to identify and quantify risk factors for IBH. Data from 3453 Friesian horse mares and 7074 Shetland pony mares scored for IBH by inspectors during obligatory foal inspections were analysed using breed-specific multivariable logistic regression models. The combined effect of month and year of scoring, Province and inspector were significantly associated with IBH in both breeds. In Shetland pony mares, withers height and coat co...
Schurink A, Ducro BJ, Bastiaansen JW, Frankena K, van Arendonk JA.Insect bite hypersensitivity (IBH) is the most common allergic disease present in horses worldwide. It has been shown that IBH is under genetic control, but the knowledge of associated genes is limited. We conducted a genome-wide association study to identify and quantify genomic regions contributing to IBH in the Dutch Shetland pony population. A total of 97 cases and 91 controls were selected and matched on withers height, coat colour and pedigree to minimise the population stratification. A blood sample was collected from participating Shetland pony mares, their IBH phenotype was scored and...
Van Weyenberg S, Buyse J, Kalmar ID, Swennen Q, Janssens GP.The relation between plasma leptin and daily ad libitum roughage intake was evaluated during a 14-day period in eight obese Shetland ponies. When the feeding strategy was changed from maintenance feeding to ad libitum feeding, feed intake increased the first day, decreased the second day and increased again during the following days to reach a constant level after 8 days. Plasma leptin concentration increased during the first 2 days, but remained constant afterwards. Although the same pattern was found in all ponies, the magnitude of the increase in leptin on day 1 and the resulting decrease i...
Govaere JL, De Schauwer C, Hoogewijs MK, Chiers K, Lefère L, Catry B, Roels K, van Heerden M, Broeckx S, de Kruif A.Hydrallantois in the mare is a very rare condition, and clinical reports help to gather information to elucidate its pathogenesis, treatment options and prognosis. Five different cases of hydrallantois in the mare are reported in this article, all with the involvement of placentitis. The five mares were presented because of acute distention of the abdomen, dyspnoea, stiff gait and a lack of appetite. After a gradual release of the excessive amount of allantoic fluid, an abortion was induced in all five mares. The foals were either born dead or euthanized. The mares recovered quickly. One mare ...
Brinkmann L, Gerken M, Riek A.Recent results suggest that the wild ancestor of the horse, the Przewalski horse, exhibits signs of a hypometabolism. However, there are speculations that domestic animals lost the ability to reduce energy expenditure during food shortage and adverse environmental conditions. Therefore, we investigated physiological and behavioural strategies employed by a robust domesticated horse breed, the Shetland pony, over the course of a year under temperate conditions by measuring ambient temperature (T(a)), subcutaneous temperature (T(s)), locomotor activity (LA), lying time, resting heart rate, body ...
Schramel J, Nagel C, Auer U, Palm F, Aurich C, Moens Y.The regional distribution of ventilation in conscious standing pregnant Shetland pony mares was investigated by Electrical Impedance Tomography (EIT). Six ponies were repeatedly examined a minimum of four weeks prior to (antepartum, AP) until three weeks after parturition (postpartum, PP). From the cross-sectional ventilation image the ventral to dorsal (V/D), left to right (L/R) ventilation distribution ratio and the relative ventilation in four horizontal regions of interest (ROI) placed symmetrically in the chest was analyzed. Antepartum V/D was 0.74 ± 0.09 on day -28 ± 3 (AP28) and decre...
Nagel C, Aurich J, Palm F, Aurich C.Heart rate (HR) is an important parameter of fetal well-being. In horses, HR and heart rate variability (HRV) can be determined by fetomaternal electrocardiography (ECG) from mid-pregnancy to foaling. Normal values for physiological parameters in larger breeds are often used as reference values in ponies. However, HR increases with decreasing size of the animal and in ponies is higher than in warmblood horses. It is not known if fetal HR is affected by breed and if values obtained in larger breeds can be used to assess Shetland fetuses. We have determined fetomaternal beat-to-beat (RR) interva...
van de Goor LH, van Haeringen WA, Lenstra JA.As a consequence of the close integration of horses into human society, equine DNA analysis has become relevant for forensic purposes. However, the information content of the equine Short Tandem Repeat (STR) loci commonly used for the identification or paternity testing has so far not been fully characterized. Population studies were performed for 17 polymorphic STR loci (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, LEX3 and VHL20) including 8641 horses representing 35 populations. The power of parental exclusion, polymorphic information content...
Brooks SA, Makvandi-Nejad S, Chu E, Allen JJ, Streeter C, Gu E, McCleery B, Murphy BA, Bellone R, Sutter NB.Horses, like many domesticated species, have been selected for broad variation in skeletal size. This variation is not only an interesting model of rapid evolutionary change during domestication, but is also directly applicable to the horse industry. Breeders select for complex traits like body size and skeletal conformation to improve marketability, function, soundness and performance in the show ring. Using a well-defined set of 35 measurements, we have identified and quantified skeletal variation in the horse species. We collected measurements from 1215 horses representing 65 breeds of dive...
Larenza MP, Peterbauer C, Landoni MF, Levionnois OL, Schatzmann U, Spadavecchia C, Thormann W.To evaluate pharmacokinetics of ketamine and norketamine enantiomers after constant rate infusion (CRI) of a subanesthetic dose of racemic ketamine or S-ketamine in ponies. Methods: Five 6-year-old Shetland pony geldings that weighed between 101 and 152 kg. Methods: In a crossover study, each pony received a CRI of racemic ketamine (loading dose, 0.6 mg/kg; CRI, 0.02 mg/kg/min) and S-ketamine (loading dose, 0.3 mg/kg; CRI, 0.01 mg/kg/min), with a 1-month interval between treatments. Arterial blood samples were collected before and at 5, 15, 30, 45, and 60 minutes during drug administration and...
Bosch G, de Mos M, van Binsbergen R, van Schie HT, van de Lest CH, van Weeren PR.Extracorporeal shock wave therapy (ESWT) is frequently used in equine practice, but little is known about its biological action. Objective: To study the effects of ESWT on matrix structure and gene expression levels in normal, physiologically loaded tendinous structures in ponies. Methods: Six Shetland ponies, free of lameness and with ultrasonographically normal flexor and extensor tendons and suspensory ligaments (SL), were used. ESWT was applied at the origin of the suspensory ligament and the mid-metacarpal region of the superficial digital flexor tendon (SDFT) 6 weeks prior to sample taki...
Wijnberg ID, Schrama SE, Elgersma AE, Maree JT, de Cocq P, Back W.Therapeutic options for stringhalt in horses are limited, whereas medical experiences with botulinum toxin type A (Botox) have been positive. To evaluate its effectiveness in horses, surface electromyography (sEMG) signals before and after injection need to be quantified. Objective: Treatment of healthy ponies and cases with Botox should reduce muscle activity in injected muscles and reduce spastic movements without adverse side effects. Methods: Unilaterally, the extensor digitorum longus, extensor digitorum lateralis and lateral vastus muscles of 6 healthy mature Shetland ponies and 2 talent...
Duehlmeier R, Hacker A, Widdel-Bigdely A, von Engelhardt W, Sallmann HP.Glucose homeostasis depends on insulin-regulated glucose uptake in the skeletal muscles and fat tissues via glucose transporter (GLUT) 4 translocation into cellular plasma membranes. The present study sought to elucidate GLUT4 expression, GLUT1 and GLUT4 translocation and glucose uptake in the skeletal muscles of Shetland ponies. Semitendinosus muscle explants were removed by open muscle biopsy from six Shetland pony geldings under general anaesthesia. The expression of GLUT4 was analysed by measuring muscle crude membrane (CM) GLUT4 protein contents. To determine the insulin-stimulated GLUT t...
Levionnois OL, Spadavecchia C, Kronen PW, Schatzmann U.To determine the minimum alveolar concentration (MAC) of isoflurane in Shetland ponies using a sequence of three different supramaximal noxious stimulations at each tested concentration of isoflurane rather than a single stimulation. Methods: Prospective, experimental trial. Methods: Seven 4-year-old, gelding Shetland ponies. Methods: The MAC of isoflurane was determined for each pony. Three different modes of electrical stimulation were applied consecutively (2 minute intervals): two using constant voltage (90 V) on the gingiva via needle- (CVneedle) or surface-electrodes (CVsurface) and one ...
Van Weyenberg S, Hesta M, Buyse J, Janssens GP.In nine initially obese ponies, a weekly weight loss according to 1% of their ideal body weight was evaluated for its impact on insulin sensitivity and metabolic profile. Weight loss was obtained solely through energy restriction, initially at 70% of maintenance energy requirements, but to maintain constant weight loss, feed amount had to be decreased to 50% and 35% of maintenance energy requirement during the course of the trial. An oral glucose tolerance test (OGTT) was performed at weeks 0, 10 and 17. Fasted blood samples were taken on weeks 0, 3, 10, 17 for analysis of triglycerides (TG), ...
Roth LS, Balkenius A, Kelber A.Arrhythmic mammals are active both during day and night if they are allowed. The arrhythmic horses are in possession of one of the largest terrestrial animal eyes and the purpose of this study is to reveal whether their eye is sensitive enough to see colours at night. During the day horses are known to have dichromatic colour vision. To disclose whether they can discriminate colours in dim light a behavioural dual choice experiment was performed. We started the training and testing at daylight intensities and the horses continued to choose correctly at a high frequency down to light intensitie...
Garré B, Gryspeerdt A, Croubels S, De Backer P, Nauwynck H.The purpose of the current study was to investigate the therapeutic efficacy of valacyclovir against EHV1 in a controlled study. Eight naïve Shetland ponies were inoculated with 10(6.5) TCID(50) of the neuropathogenic strain 03P37. Four ponies were treated with valacyclovir at a dosage of 40mg/kg bodyweight, 3 times daily, for 5 (n=2) or 7 (n=2) consecutive days, while the other four ponies served as untreated controls. The treatment regimen started 1h before inoculation. Ponies were monitored daily for clinical signs. At 0, 1, 2, 3, 4, 5, 7, 9, 11, 14, 17 and 21 days post inoculation (d pi),...
Schurink A, van Grevenhof EM, Ducro BJ, van Arendonk JA.Insect bite hypersensitivity (IBH) is a seasonal recurrent allergic reaction of horses to the bites of certain Culicoides spp. and is found throughout the world. The aim of our study was to estimate the heritability and repeatability of IBH in the Dutch Shetland pony population. A total of 7,924 IBH scores on 6,073 mares were collected during foal inspections in 2003, 2005, and 2006. Mares were scored for clinical symptoms of IBH from June until February by 16 inspectors. Of all mares, 74.4% (n = 4,520) had a single observation, 20.7% (n = 1,255) had 2 observations, and 4.9% (n = 298) had 3 ob...
Goodwin D, Levine M, McGreevy PD.Paedomorphosis is the retention of juvenile morphology at maturity and is important in generating evolutionary change in domestic species and species in the wild. When comparing dogs with the wolf, this preliminary study saw paedomorphosis in their physical and behavioral traits (Goodwin, Bradshaw, & Wickens, 1997). This preliminary study compared morphological characteristics of 10 breeds from northern regions (Shetland ponies) and southern regions (Arabians) with the Exmoor pony. Twenty-three respondents from the United Kingdom and Australia rated the breeds for 7 physical traits. As evi...
Bochröder B, Schubert R, Bödeker D.Discs of stripped mucosa from the proximal ventral colon were prepared immediately after slaughter of 8 Shetland cross-breed ponies. The mucosae were fixed in incubation chambers and used in incubation experiments to study the transmucosal fluxes of the amino acids lysine, histidine and arginine (150 min) and of ammonia (90 min). When the amino acid concentrations in the mucosal solution were in the physiological range (2.8-3.0 mmol/l) no transport to the serosal side of the tissue was found. When the concentrations were raised 10-fold, less than 2% of the mucosal amino acid pool was recovered...
Spadavecchia C, Levionnois O, Kronen PW, Leandri M, Spadavecchia L, Schatzmann U.To investigate effects of isoflurane at approximately the minimum alveolar concentration (MAC) on the nociceptive withdrawal reflex (NWR) of the forelimb of ponies as a method for quantifying anesthetic potency. Methods: 7 healthy adult Shetland ponies. Methods: Individual MAC (iMAC) for isoflurane was determined for each pony. Then, effects of isoflurane administered at 0.85, 0.95, and 1.05 iMAC on the NWR were assessed. At each concentration, the NWR threshold was defined electromyographically for the common digital extensor and deltoid muscles by stimulating the digital nerve; additional el...
Watson TD, Burns L, Love S, Packard CJ, Shepherd J.Plasma lipoproteins were isolated from eight Thoroughbred horses and eight Shetland ponies on the basis of particle size by gel filtration chromatography and according to density using rate-zonal ultracentrifugation. Three major classes corresponding to very low density lipoproteins (VLDL), low density lipoproteins (LDL) and high density lipoproteins (HDL) were identified and characterised by their lipid and apolipoprotein compositions. The particle size distributions of each class were determined by electron microscopy and non-denaturing polyacrylamide gradient gel electrophoresis. HDL was fo...
Klouth E, Zablotski Y, Goehring LS.Equid herpesvirus type 1 (EHV-1) causes several outbreaks of abortion and/or equid herpesvirus-associated myeloencephalopathy (EHM) worldwide each year. EHM is of great concern, as permanent neurological gait anomalies can leave a horse unfit for future use. The study assesses the risk factors associated with the occurrence of EHM. During an unmitigated outbreak, 141 adult horses/ponies of several distinct breeds were evaluated-using multiple Bayesian logistic regression calculating the odds ratios for breed, age, and sex. In total, 33 of the 141 horses showed signs of EHM. Fjord horses and wa...
Meulenbroeks C, van der Meide NM, Willemse T, Rutten VP, Tijhaar E.Ponies may suffer from Insect bite hypersensitivity (IBH), an allergic IgE-mediated pruritic skin disorder, induced by allergens from biting midges of the Culicoides spp. Objective: To determine whether recombinant Culicoides obsoletus allergens are able to activate T cells of ponies exposed to C. obsoletus and whether these allergen-specific responses differ between IBH-affected and healthy ponies. Methods: Ten IBH-affected Shetland ponies and 10 age-matched healthy controls taken from the same stables, to ensure similar exposure to midges. Methods: Peripheral blood mononuclear cells (PBMC) w...
Schurink A, Podesta SC, Ducro BJ, van Arendonk JA, Frankena K.Insect bite hypersensitivity (IBH) is an equine skin allergy caused by bites of Culicoides spp. and impacts on the welfare of affected horses. The aim of this study was to identify and quantify risk factors for IBH. Data from 3453 Friesian horse mares and 7074 Shetland pony mares scored for IBH by inspectors during obligatory foal inspections were analysed using breed-specific multivariable logistic regression models. The combined effect of month and year of scoring, Province and inspector were significantly associated with IBH in both breeds. In Shetland pony mares, withers height and coat co...
Martin BW, Terry MK, Bridges CH, Bailey EM.Three Shetland ponies were given a single oral dose of ground Cassia occidentalis seeds in aqueous suspension. The clinical signs observed resembled those seen in naturally occurring and experimental cases in cattle. The syndrome was characterized by an afebrile course, incoordination, recumbency and death. Elevations of blood alkaline phosphatase, CPK, LDH, and SGOT were observed. Although muscle lesions were not seen grossly, microscopic lesions included segmental necrosis of skeletal muscle fibers. The findings were regarded as sufficiently characteristic of C. occidentalis poisoning to be ...
Clegg PD, Butson RJ.A nine-year-old Shetland pony gelding, with a history of recurrent upward fixation of the patella, suddenly developed severe lameness in its right hindlimb. A luxation of the coxofemoral joint was diagnosed by a clinical and radiographic examination. The initial treatment of the luxation by closed reduction was not maintained, and the limb was placed in an Ehmer sling for four days after a second closed reduction. This allowed the femoral head to remain in the acetabulum, although a persistent subluxation remained, presumably owing to a rupture of the round ligament. The pony remained comforta...
Mullaney TP, Brown CM.Newborn Shetland foals died of acute hepatic failure following oral administration of approximately 16 mg/kg body weight ferrous fumarate. Lesions in these foals were indistinguishable from lesions in foals given an oral digestive inoculant containing ferrous fumarate and were also similar to the syndrome characterised as 'toxic hepatopathy' in foals in the United States in 1983. We conclude that foals are susceptible to toxicity from low doses of iron compounds in the first few days of life. Vitamin E and selenium deficiency may contribute to this susceptibility.
Deichsel K, Pasing S, Erber R, Ille N, Palme R, Aurich J, Aurich C.The use of breeding stallions for equestrian competitions requires that fertility is not negatively affected by competition or transport to the competition site. In this study, effects of cortisol release induced by road transport (600 km), adrenocorticotropic hormone (ACTH) administration (3 × 0.5 mg synthetic ACTH) and placebo treatment on semen quality and testosterone release were investigated in Shetland stallions (N = 13) using a crossover design. Saliva for cortisol and blood for testosterone analysis were collected for 10 weeks after treatments. Semen was collected daily for 5 days di...
Adamska M, Skotarczak B.The purpose of this study was to detect piroplasms, which are pathogens of veterinary and zoonotic importance in ticks, that were collected from ponies and field vegetation and to determine the role of Shetland ponies as potential reservoir hosts for piroplasms. A total of 1737 feeding and 371 questing Ixodes ricinus collected from horses or vegetation were tested for the presence of Babesia and Theileria DNA. Piroplasm 18S rRNA gene amplification was conducted, and the obtained amplicons were sequenced. Babesia DNA was detected in only three ticks (one tick collected from a pony and two colle...
McChesney SL, England JJ, McChesney AE.An agent lethal to embryonated chicken eggs was isolated from lung tissues of a quarter horse mare with a fatal respiratory disease. The lesions induced in embryonated chicken eggs, the tinctoral properties, the ultrastructural morphology, the resistance of the organism to sodium sulfadiazine, and the presence of a chlamydial complement fixing antigen, identify this isolate as a member of the family Chlamydiaceae and suggest the agent to be Chlamydia psittaci. Two Shetland ponies experimentally infected with the isolated agent developed subclinical infection as demonstrated by an increase in c...
Schurink A, van der Meide NM, Savelkoul HF, Ducro BJ, Tijhaar E.Insect bite hypersensitivity (IBH) is a common allergic skin disease in horses, caused by biting insects of the Culicoides spp. In The Netherlands, Culicoides spp. of the Obsoletus complex are the most important midges involved in IBH. The aim of the present study was to identify and quantify associations between several endogenous (host) and exogenous (environmental) factors and immunoglobulin E (IgE) reactivity against Obsoletus complex-derived whole body extract or seven recombinant allergens, measured by ELISA. Data from 143 Icelandic horses and 177 Shetland ponies were analysed using mult...
Gromadzka-Ostrowska J, Zalewska B, Jakubów K, Gozlinski H.Changes in some trace minerals concentrations (calcium, inorganic phosphorus, magnesium, zinc, iron, copper, sodium and potassium) in blood plasma were investigated during a three-year period in Shetland pony mares. Blood plasma mineral concentrations were determined by the atomic absorption method and colorimetric method. The three-year averages were in micrograms/ml; Na 4630 +/- 168; K 277 +/- 3.8; Ca 171 +/- 3.8; P 31.5 +/- 0.74; Fe 1.92 +/- 0.14; Zn 1.07 +/- 0.04 and Cu 1.06 +/- 0.02. Two trace minerals (magnesium in inorganic phosphorus) showed only long-term tendency changes--upward or d...
D'Fonseca NMM, Gibson CME, Hummel I, van Doorn DA, Roelfsema E, Stout TAE, van den Broek J, de Ruijter-Villani M.Obesity has been associated with altered reproductive activity in mares, and may negatively affect fertility. To examine the influence of long-term high-energy (HE) feeding on fertility, Shetland pony mares were fed a diet containing 200% of net energy (NE) requirements during a three-year study. The incidence of hemorrhagic anovulatory follicles (HAF) and annual duration of cyclicity were compared to those in control mares receiving a maintenance diet. Day-7 embryos were flushed and transferred between donor and recipient mares from both groups; the resulting conceptuses were collected 21 day...
Drudge JH, Lyons ET, Tolliver SC, Swerczek TW.Oxibendazole (OBZ; 10 mg/kg of body weight) was administered to ponies at 8-week intervals to control strongylosis in a breeding band of Shetland-type ponies (n = 29 to 50) from October 1978 through September 1984. A similar use of cambendazole (CBZ; 20 mg/kg of body weight) in this band of ponies during the preceding 4-year period resulted in the survival of a CBZ-resistant population (S) of small strongyles. Effectiveness of OBZ treatments was monitored by pre- and posttreatment counts of the number of strongyle eggs per gram of feces (epg) and of the number of strongyle larvae per gram of f...
Sleutjens J, Serra Bragança FM, van Empelen MW, Ten Have RE, de Zwaan J, Roelfsema E, Oosterlinck M, Back W.Obesity and hyperinsulinaemia are frequently encountered in the equine population and risk factors for the development of laminitis. There are many options for hoof support that claim a beneficial effect, but often the scientific evidence is scarce. Objective: To quantify the effect of frog-supportive shoes on hoof kinetics in normal and obese ponies. Methods: Controlled in vivo trial. Methods: Ten Shetland mares (n = 10) with a normal (n = 5) or obese (n = 5) body condition were led over a dynamically calibrated pressure plate before (T0), immediately after (T1) and 72 h (T2) after ap...
Ross MW, Lowe JE, Cooper BJ, Reimers TJ, Froscher BA.A 12-year-old, 195 kg Shetland pony broodmare had eight seizures between May 29 and August 7, 1979. Plasma glucose levels during three of these seizures were markedly depressed (16, 18 and 19 mg/100 ml). Serum insulin levels were elevated during two of the seizures (86.0 and 97.7 microU/ml). Although a fasting hypoglycemia was not demonstrated, plasma glucose values during a normal day were abnormal; a plasma glucose level of 42 mg/100 ml was noted eight hours post-feeding. Serum insulin values obtained during an oral glucose tolerance test and intravenous glucagon tolerance test were consiste...
Mirmojarabian SA, Kajabi AW, Ketola JHJ, Nykänen O, Liimatainen T, Nieminen MT, Nissi MJ, Casula V.Machine learning models trained with multiparametric quantitative MRIs (qMRIs) have the potential to provide valuable information about the structural composition of articular cartilage. To study the performance and feasibility of machine learning models combined with qMRIs for noninvasive assessment of collagen fiber orientation and proteoglycan content. Retrospective, animal model. An open-source single slice MRI dataset obtained from 20 samples of 10 Shetland ponies (seven with surgically induced cartilage lesions followed by treatment and three healthy controls) yielded to 1600 data points...
Sandersen CF, Detilleux J, Delguste C, Pierard L, van Loon G, Amory H.High-dose dobutamine stress echocardiography has been shown to be cardiotoxic and arrhythmogenic in horses. However, the test may have benefit in practice as a pharmacological challenge of exercise without the treadmill being required. Objective: To investigate the effect of low-dose dobutamine on cardiac performance in ponies previously treated with atropine, in order to develop a pharmacological protocol that allows examination of the equine heart under stimulation. Methods: In 13 healthy Shetland ponies, heart rate (HR), stroke index (SI) and cardiac index (CI) were calculated from pulsed-w...
Trachsel D, Tschudi P, Portier CJ, Kuhn M, Thormann W, Scholtysik G, Mevissen M.Atrial fibrillation is a well-known heart disease in horses. The common therapy consists of administration of quinidine. More potent antiarrhythmic drugs have become available for human therapy and the use of these as alternatives to quinidine for equine antiarrhythmic therapy is a matter of interest. Amiodarone (AMD) is used in human medicine for treatment of many arrhythmias, including atrial fibrillation. Its disposition in horses has not yet been investigated. The purpose of this study was to measure the effect of single intravenous doses of amiodarone (5 and 7 mg/kg) on the surface electr...
Brinkmann L, Gerken M, Riek A.Water is an essential nutrient necessary to support life, and adequate water supply is crucial for animal survival and productivity. The present study was designed to determine seasonal changes in the water metabolism of horses under outdoor conditions. Total body water (TBW) and total water intake (TWI) of 10 adult Shetland pony mares were estimated at monthly intervals for 14 mo by using the deuterium dilution technique. During the last 4 mo, 5 ponies were fed restrictively to simulate natural feed shortage in winter, and 5 ponies served as controls. The TBW (kg) was closely related to body ...
Schmidt O, Deegen E, Fuhrmann H, Dühlmeier R, Sallmann HP.The aim of this study was to investigate the influence of a fat-supplemented diet compared with a carbohydrate diet on the lipid metabolism and the enteroinsular axis of Shetland ponies. The 'crossover' experiment was divided into two parts: in the first 10 weeks the diets comprised the correct number of calories according to requirements and in the following 10 weeks they were hypercaloric, in order to check the effect of a different energy content of the diets. Feeding the fat-enriched diet, independently of its energy content, led to a significant decrease in plasma triglycerides, associate...
Ohnuma K, Yokoo M, Ito K, Nambo Y, Miyake YI, Komatsu M, Takahashi J.Early pregnancy factor (EPF) is an immunosuppressive protein detected in the early pregnancy serum. We have already reported that we developed the rosette inhibition test for mare EPF and detected EPF in thoroughbreds. The aim of this study was to determine whether or not our method could be used clinically. Methods: The rosette inhibition test for equine EPF was carried out on serum from six nonpregnant and six pregnant Shetland ponies, a female and a male Chinese pony, and four nonpregnant and 13 pregnant thoroughbred mares. In the thoroughbreds sera were collected during the pregnancy perio...
Eysker M, Boersema JH, Kooyman FN.Two groups of three ponies were used to study the effect of three ivermectin or pyrantel treatments given at intervals of 5 weeks at the beginning of the grazing season. Although each pyrantel treatment resulted in a greater than 95% reduction in faecal egg counts during the first 3 weeks, high pasture larval counts were seen from the beginning of August onwards and substantial cyathostomine burdens were found at necropsy in December. The ivermectin treatments resulted in an even more pronounced reduction in faecal egg output, and the pasture larval counts and cyathostomine burdens at necropsy...
Aurich JE, Kranski S, Parvizi N, Aurich C.This study investigated the regulation of growth hormone (GH) release in stallions and tested the hypothesis that the somatotrophic axis influences testicular function. Basal plasma GH concentrations, effects of an experimental decrease of GH release on testicular function and an opioidergic regulation of GH release were investigated in Shetland stallions (n=6). No seasonal variations in plasma GH concentrations were found over a 12-month period. Treatment with the somatostatin analogue octreotid (100mg twice daily over 10 days) caused a decrease in semen motility from 38.7+/-8.4% progressivel...
Eysker M, Mirck MH.The distribution of inhibited early third stage Cyathostominae larvae in different parts of the large intestine of the horse was studied in 20 Shetland ponies necropsied in autumn 1982, 1983 and 1984. The location of the larvae in the large intestinal wall was studied by histological examination of the intestines of the eight ponies from 1984. Inhibited larvae were located predominantly and more or less equally in the caecum and the ventral colon. Generally fewer early L3 were in the dorsal colon. In 1984 a considerable proportion (mean 17%, range 9.7-36.9%) of the inhibited larvae was found i...
Claeys I, Van der Vekens E, Kümmerle J, de Preux M, Koch C.To develop a minimally invasive technique for placing a toggle construct across the coxofemoral joint of small equids using computer-assisted surgery. Methods: Experimental cadaveric study. Methods: Three pilot specimens: One donkey, one Shetland pony and one Warmblood foal. Six main study specimens: Three Shetland ponies, one American Miniature Horse, one Warmblood foal and one donkey. Methods: Experimental surgeries were performed on both coxofemoral joints of each cadaver. Using a minimally invasive surgical approach, 5.5 mm bone canals were drilled through the femur and acetabulum, trave...
