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.
Alberghina D, Tombolani C, Quintavalla F.Evaluating the body temperature of horses () is essential for monitoring their health. Rectal thermometry is the most common method for determining the temperatures of adult horses and foals. However, this method requires restraining the animals for several seconds, and it poses potential risks to both horses and humans. This study compared infrared and rectal thermometry in 126 horses, evaluating age and measurement site influences on body temperature. Horses were divided into three groups: foals (4-12 months), Shetland ponies (8-12 months), and adult horses (2-30 years). Rectal, ocular...
Carnevale L, Tagliabue T, Rabbogliatti V, Bona R, Cavallier F.Femoral head ostectomy is considered a salvage procedure in the treatment of chronic coxofemoral joint luxation in small equids. Permanent lameness of varying degrees, largely depending on the animal's weight, and potential contralateral limb deformity may occur. The purpose of this study was to report the outcome of a small equid that, despite undergoing a femoral head ostectomy for a chronic coxofemoral joint luxation, was able to return to being ridden by children and to athletic activities. Methods: An 8-year-old Shetland pony mare (180 kg) was presented for a chronic right hind limb lamen...
Spoormakers TJP, Veraa S, Graat EAM, van Weeren PR, Brommer H.Data on equine thoracic pathology hardly exist in breeds other than Thoroughbreds. Objective: To describe pathological changes of the osseous thoracic vertebral column in Warmblood horses, Shetland ponies and Konik horses, and to compare prevalence and severity. Methods: Descriptive post-mortem study. Methods: Computed tomography was used to examine the thoracic vertebral column of 34 Warmblood horses, 28 Shetland ponies, and 18 Konik horses. Osteoarthritis (OA), periarticular osteolysis, osseous cyst-like lesions and fragments of articular processes (APJs), costovertebral and costotransverse ...
Wagner LH, Aurich J, Claaßen S, Melchert M, Kaps M, Aurich C.Transrectal and transabdominal ultrasonography is an established method to monitor pregnancy, fetal growth and wellbeing in different species. Growth charts with multiple bio-morphometric parameters to estimate days of gestation and days before parturition exist in small companion animals, sheep and goats, riding type horses and large ponies but not in small horse breeds like Shetland ponies. The aim of this study was to apply fetal biometric assessment and detailed description of physiologic fetal development to mid and late term pregnancies in Shetland mares and to generate reference data fo...
Greppi M, Bordin C, Raspa F, Maccone E, Harris P, Ellis AD, Cavallini D, Bergero D, Valle E.Slow feeding devices (SFDs) are useful tools in order to improve the horse well-being and to reduce wastage, but their use may result in unnatural posture during feeding and frustration behaviours. Moreover, it may be important to evaluate the laterality during feeding. The aim of the study was to investigate ponies' feeding behaviour (i.e., lateralisation, frustration, postural eating style) with different hay feeding methods: on the ground (G), a fully filled hay net (HF), a partially filled hay net (HL), and a slow feeder hay box (HB). Nine ponies of two different breed types (Shetland and ...
Determination of morphological and biochemical blood indices facilitates assessment of the health and welfare of horses, their nutrient demand, the effects of training already undertaken, and the horses' suitability for exercise. Identification of the season-dependent components and the effects of sex and exercise on changes in frequently referenced haematological and biochemical parameters was the main goal of the current study. Unassigned: The blood morphology of 21 healthy adult Shetland ponies (11 mares and 10 stallions) aged 6.5 ± 1.4 years from the central Pomeranian region in Poland wa...
Spoormakers TJP, Veraa S, Graat EAM, van Weeren PR, Brommer H.Data on equine lumbar pathology hardly exist in breeds other than Thoroughbreds. Objective: To describe pathological changes of the osseous lumbar vertebral column in Warmblood horses, Shetland ponies and Konik horses. Methods: Descriptive post-mortem study. Methods: The lumbar vertebral columns of 34 Warmblood horses, 28 Shetland ponies, and 18 Konik horses were examined by computed tomography (CT). Osteoarthritis (OA) of articular processes (APJs), OA of intertransverse joints (ITJs), intervertebral disc (IVD) mineralisation, impingement of spinous (SPs) and transverse (TPs) processes and sp...
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...
Bordin C, Raspa F, Harris P, Ellis AD, Roggero A, Palestrini C, Bergero D, Valle E.The application of hay feeding devices, such as the use of hay nets or slow feeders, can help with the management of weight in ponies; however, there is still a lack of knowledge regarding their effect on equine posture. Therefore, the aim of the study was to assess the effect of different feeding devices on the posture of ponies using morphometric analysis. Two different breed types, Shetland type (SH, n = 5) versus Welsh Cob type (WC, n = 4), were fed the same forage in four different ways: on the ground (G), using a fully filled haynet (HF), using a partially filled haynet (HL) and...
Schinköthe J, Gerlach K, Ulrich RG, Brehm W.A 12-y-old Shetland Pony was presented with a mucus-secreting fistula in the right paralumbar fossa. Surgery was performed to unravel the origin of the fistula. The horse died under anesthesia and was forwarded to autopsy. The right kidney was markedly atrophic and fibrotic, consistent with unilateral end-stage kidney. The right ureter was markedly thickened, but with luminal continuity leading into the urinary bladder where a partial obstruction caused by nodular para-ureteral fat necrosis was evident. The lumen of the cutaneous fistula was continuous with the right ureter; therefore, we diag...
Pala S, Hänninen NE, Mohammadi A, Ebrahimi M, Te Moller NCR, Brommer H, René van Weeren P, Mäkelä JTA, Korhonen RK, Afara IO, Töyräs J....The aim of this study is to assess whether articular cartilage changes in an equine model of post-traumatic osteoarthritis (PTOA), induced by surgical creation of standard (blunt) grooves, and very subtle sharp grooves, could be detected with ex vivo T relaxation time mapping utilizing three-dimensional (3D) readout sequence with zero echo time. Grooves were made on the articular surfaces of the middle carpal and radiocarpal joints of nine mature Shetland ponies and osteochondral samples were harvested at 39 weeks after being euthanized under respective ethical permissions. T relaxation times ...
Bamford NJ, Stewart AJ, El-Hage CM, Bertin FR, Bailey SR.Plasma adrenocorticotropic hormone (ACTH) concentration is commonly measured to diagnose pituitary pars intermedia dysfunction (PPID). Several intrinsic and extrinsic factors affect ACTH concentrations, including breed. The objective of this study was to prospectively compare plasma ACTH concentrations among different breeds of mature horses and ponies. Three breed groups comprised Thoroughbred horses (n = 127), Shetland ponies (n = 131) and ponies of non-Shetland breeds (n = 141). Enrolled animals did not show any signs of illness, lameness or clinical signs consistent with PPID. Blood ...
Regnier A, Landrevie C, Robin MC, Einsweiler D, Douet JY, Raymond-Letron I.A 6-year-old miniature Shetland pony mare was referred for evaluation of a left corneal mass, which developed from the healing tissue of a corneal traumatic ulceration that had occurred 4 weeks previously. On gross examination, a spherical, smooth-surfaced, and pink-colored lesion of about 1 cm in diameter was protruding from the left palpebral fissure. Ophthalmic examination revealed that it was attached to the scar tissue of the cornea, and that one corpora nigra was adherent to the posterior face of corneal wounded area, without sign of uveitis. The remainder of the ophthalmic examinatio...
Müller EMT, Ehrle A, Pozzi A, Lasarzik de Ascurra J, Lischer CJ, Kümmerle JM.To describe open reduction and surgical stabilization of a coxofemoral luxation in a pony using a modified toggle pin technique and prosthetic joint capsule reconstruction without osteotomy of the greater trochanter. Methods: A 2-year-old Shetland pony with a bodyweight of 167 kg. Methods: Case report. Methods: Radiographic examination confirmed craniodorsal luxation of the left coxofemoral joint. An open reduction with the aid of a pulley system was performed. A toggle pin was inserted through a bone tunnel extending from the level of the femoral shaft through the femoral head and the cente...
Gautier C, Aurich J, Kaps M, Okada CTC, Wagner LH, Melchert M, Aurich C.In stallions temporarily not intended for breeding, reversible suppression of testicular function by vaccination against GnRH can be of interest. In the present study, effects of GnRH agonist treatment on the resumption of testicular function after GnRH vaccination were investigated. Testis size, testosterone release, semen characteristics and behavior were evaluated. We hypothesized that GnRH agonist treatment would restore testicular function. Shetland stallions were assigned to an experimental and a control group (n = 6 each). Experimental stallions were GnRH-immunized twice, four weeks a...
Bao W, Yu J, He Y, Liu M, Yang X.The intestinal flora has a variety of physiological functions involved in the regulation of host metabolism, immunity and endocrinology, and plays an important role in maintaining the health of the host. In this study, we used high-throughput sequencing technology to analyze the intestinal bacterial diversity and their gene functions in three equine species of the genus Shetland Pony (SP), Mongolian Wild Ass (MA), and Plain Zebra (PZ) in captivity in two wildlife parks in Inner Mongolia Autonomous Region, China. The results showed that only the SP intestinal bacterial abundance index (Chao1) w...
The objective of the current study was to determine the photoperiod-induced variations and the impact of exercise on oxidative stress biomarkers [2-thiobarbituric acid reactive substances (TBARS), aldehydic (AD) and ketonic (KD) derivatives of oxidatively modified proteins (OMP), total antioxidant capacity (TAC), and activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx)] and biomarkers of metabolic alterations [glucose, urea, and uric acid and the activity of lactate dehydrogenase (LDH)] in the blood of Shetland pony mares and stallions involved in recreati...
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...
Kutara K, Ono T, Hisaeda K, Inoue Y, Henmi C, Sho K, Ohnishi A, Ohzawa E, Une Y, Iwata E, Shibano K, Asanuma T, Kitagawa H.Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult...
Durham AE, Potier JF, Huber L.Use of plasma adrenocorticotropic hormone (ACTH) concentrations for the diagnosis of PPID in equids requires awareness of other factors that might influence ACTH concentrations, including breed and time of year. This study was designed to investigate effects of breed on plasma ACTH concentrations and potential interactions between breed and time of year. Ten breeds were selected from a laboratory database containing data on plasma ACTH concentrations. Breeds represented were Arabians, Cobs, Connemara ponies, donkeys, Irish Sports horses, New Forest ponies, Shetland ponies, Thoroughbreds, Warmb...
Mohammadi A, Te Moller NCR, Ebrahimi M, Plomp S, Brommer H, van Weeren PR, Mäkelä JTA, Töyräs J, Korhonen RK.In this study, we mapped and quantified changes of proteoglycan (PG) content and biomechanical properties in articular cartilage in which either blunt or sharp grooves had been made, both close to the groove and more remote of it, and at the opposing joint surface (kissing site) in equine carpal joints. In nine adult Shetland ponies, standardized blunt and sharp grooves were surgically made in the radiocarpal and middle carpal joints of a randomly chosen front limb. The contralateral control limb was sham-operated. At 39 weeks after surgery, ponies were euthanized. In 10 regions of interest (...
Honkanen MKM, Mohammadi A, Te Moller NCR, Ebrahimi M, Xu W, Plomp S, Pouran B, Lehto VP, Brommer H, van Weeren PR, Korhonen RK, Töyräs J....Post-traumatic osteoarthritis is a frequent joint disease in the horse. Currently, equine medicine lacks effective methods to diagnose the severity of chondral defects after an injury. Objective: To investigate the capability of dual-contrast-enhanced computed tomography (dual-CECT) for detection of chondral lesions and evaluation of the severity of articular cartilage degeneration in the equine carpus ex vivo. Methods: Pre-clinical experimental study. Methods: In nine Shetland ponies, blunt and sharp grooves were randomly created (in vivo) in the cartilage of radiocarpal and middle carpal joi...
Enke N, Brinkmann L, Südekum KH, Tholen E, Gerken M.Horses lose high amounts of Na through excessive sweating. These fluid losses can often not be replaced completely by voluntary water intake, requiring saline solutions as rehydration therapy to regain electrolyte balance. The experiment aimed to evaluate the sensitivity and tolerance of Shetland ponies towards different Na concentrations in their drinking water and contained three phases: (1) control: only fresh water provided; (2) pairwise-preference test: choice between fresh water and saline solution with stepwise increasing sodium chloride (NaCl) concentration (0.25%, 0.5%, 0.75%, 1.0%, 1...
Esdaile E, Kallenberg A, Avila F, Bellone RR.Coat color is a trait of economic significance in horses. Variants in seven genes have been documented to cause white patterning in horses. Of the 34 variants that have been identified in KIT proto-oncogene, receptor tyrosine kinase (), 27 have only been reported in a single individual or family and thus not all are routinely offered for genetic testing. Therefore, to enable proper use of marker-assisted selection, determining breed specificity for these alleles is warranted. Screening 19 unregistered all-white Shetland ponies for 16 white patterning markers identified 14 individuals whose phe...
Hermans H, van den Berg EMH, Slenter IJM, Vendrig DJC, de Nijs-Tjon LJL, Vernooij JCM, Brommer H, Boevé MH, Gehring R.Topical dexamethasone and prednisolone are currently the mainstay treatment for equine ophthalmic inflammatory diseases, such as equine recurrent uveitis. Comparative pharmacokinetic studies in horses are lacking and current guidelines are mainly based on empirical data and extrapolation from other species. Objective: To investigate the penetration and local concentrations of topically applied dexamethasone and prednisolone in normal equine ocular fluids and serum. Methods: Prospective randomised experimental pharmacokinetic study. Methods: Twenty-one Shetland ponies without ophthalmic disease...
Dias IR, Maia LM, Quaresma M, Cotovio M, Silva FC.Complete fractures of the third metacarpal/metatarsal bones (Mc/t3) are not common, but can occur in various situations and all types of horses, contributing for approximately one third of all long bone fractures in the horse, mostly related to external trauma or to high energy injuries. To stabilize Mc/t3 fractures in the horse, conservative management with walking casts and/or open reduction and internal fixation techniques are referred in the scientific literature, these last one generally by double platting application to bone surface in 90 degrees. In the present case will be described a ...
Schweinsberg LP, Ehrle A, Schweinsberg U, Meehan L, Noguera Cender A, Lischer CJ.To describe the surgical correction of a multiplanar deformity of the radius in a pony using a single-cut osteotomy. Methods: Case report. Methods: A 9-week-old male Shetland pony foal with a bodyweight of 47 kg. Methods: The foal presented with a complex multiplanar deformity of the right radius. A 3-dimensional model of the bone was created based on computed tomography (CT) imaging. To correct the deformity, the cutting plane for a single-cut osteotomy was calculated following the mathematical approach described by Sangeorzan et al. After osteotomy, the bone was realigned and stabilized wi...
D' Fonseca NMM, Gibson CME, van Doorn DA, Roelfsema E, de Ruijter-Villani M, Stout TAE.Maternal overfeeding is associated with disturbances in early embryonic epigenetic reprogramming, leading to altered expression of imprinted genes and nutrient transporters, which can affect both fetal and placental development and have lasting effects on the health of resulting offspring. To examine how maternal overfeeding affects the equine embryo, Shetland pony mares were fed either a high-energy (HE: 200% of net energy requirements) or maintenance (control) diet. Mares from both groups were inseminated, and day-seven embryos were recovered and transferred to recipients from the same or th...
Calero Rodriguez A, de Grauw JC, van Loon JPAM.To determine the effect of fraction of inspired oxygen (FiO) on intrapulmonary shunt fraction as measured by F-shunt in ponies during isoflurane anaesthesia. Methods: Prospective, randomized clinical study. Methods: A group of 23 adult Shetland ponies undergoing a total of 32 anaesthetic procedures. Methods: Ponies were premedicated intravenously (IV) with detomidine (0.01 mg kg) and either morphine (0.1 mg kg) or butorphanol (0.02 mg kg). Anaesthesia was induced with ketamine (2.2 mg kg) and midazolam (0.07 mg kg) administered IV. Ponies were randomly allocated to maintenance of anaesthesia w...
D' Fonseca NMM, Beukers M, Wijnberg ID, Navas de Solis C, de Ruijter-Villani M, van Doorn DA, Stout TAE, Roelfsema E.Changes in cardiovascular parameters, including blood pressure (BP) and cardiac anatomical dimensions, are an inconsistent feature of the equine metabolic syndrome. The order in which these changes arise is unknown. Objective: Determine the order in which EMS-associated changes in cardiovascular parameters arise. Methods: Twenty Shetland pony mares. Methods: High-energy (HE) diet mares were fed 200% of net energy requirements for 1 (n = 3) or 2 (n = 7) consecutive diet-years, with 17 weeks of hay-only between years. Noninvasive BP measurements and echocardiograms were performed during bo...
Salinovich O, Payne SL, Montelaro RC, Hussain KA, Issel CJ, Schnorr KL.Previous results from our laboratory have demonstrated that equine infectious anemia virus displays structural variations in its surface glycoproteins and RNA genome during passage and chronic infections in experimentally infected Shetland ponies (Montelaro et al., J. Biol. Chem. 259:10539-10544, 1984; Payne et al., J. Gen. Virol. 65:1395-1399, 1984). The present study was undertaken to obtain an antigenic and biochemical characterization of equine infectious anemia virus isolates recovered from an experimentally infected pony during sequential disease episodes, each separated by intervals of ...
Lichtenstein DL, Rushlow KE, Cook RF, Raabe ML, Swardson CJ, Kociba GJ, Issel CJ, Montelaro RC.As an important enzyme in DNA synthesis, dUTPase is present in a wide variety of organisms and viruses and has been identified as a component of the equine infectious anemia virus (EIAV) pol gene. The role of EIAV dUTPase, designated DU, in virus replication in vitro and in vivo was investigated with a recently described infectious molecular clone of EIAV. A deletion mutant that was deficient in dUTPase activity was constructed, and its replication kinetics was examined in fetal equine kidney (FEK) cells and primary equine bone marrow macrophage (EBMM) cells. In FEK cells, which are permissive...
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...
Frischknecht M, Jagannathan V, Plattet P, Neuditschko M, Signer-Hasler H, Bachmann I, Pacholewska A, Drögemüller C, Dietschi E, Flury C, Rieder S....The identification of quantitative trait loci (QTL) such as height and their underlying causative variants is still challenging and often requires large sample sizes. In humans hundreds of loci with small effects control the heritable portion of height variability. In domestic animals, typically only a few loci with comparatively large effects explain a major fraction of the heritability. We investigated height at withers in Shetland ponies and mapped a QTL to ECA 6 by genome-wide association (GWAS) using a small cohort of only 48 animals and the Illumina equine SNP70 BeadChip. Fine-mapping re...
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...
Wang SZ, Rushlow KE, Issel CJ, Cook RF, Cook SJ, Raabe ML, Chong YH, Costa L, Montelaro RC.The potential for antibody-dependent enhancement of replication of macrophage/monocyte tropic viruses has posed a significant problem in the development of vaccines for several animal and human viruses and has raised significant concern in the design of potential AIDS vaccines. Using the previously described equine infectious anemia virus/Shetland pony system as a model for HIV-1 vaccine development, we have evaluated the efficacy of a recombinant subunit vaccine containing a baculovirus-expressed envelope surface glycoprotein (gp90) of EIAV. The results of these trials demonstrate not only th...
Payne SL, Salinovich O, Nauman SM, Issel CJ, Montelaro RC.Comparisons of peptide and oligonucleotide maps of glycoproteins and RNA from nine isolates of equine infectious anemia virus (EIAV) that were generated during parallel infections of two Shetland ponies revealed that each isolate was structurally unique. Each EIAV isolate contained a unique subset of variant peptides, oligonucleotides, or both, indicating that structural variation in EIAV is a random and noncumulative process and that a large spectrum of possible EIAV variants can be generated in infected animals.
Orrego A, Issel CJ, Montelaro RC, Adams WV.Five serial passages of a cell-adapted strain of equine infectious anemia (EIA) virus were conducted in Shetland ponies. The 13 recipient ponies became agar-gel immunodiffusion test-positive by 25 days after they were inoculated. The virulence of the cell-adapted strain of EIA virus markedly increased through 3 serial passages, although individual variation within passages was high. The 1st serial-passage recipient remained afebrile through 200 days, whereas a febrile episode occurred about every 185, 44, 35, and 33 days in the 2nd, 3rd, 4th, and 5th serial-passage recipients, respectively. Se...
Bosch G, Lin YL, van Schie HT, van De Lest CH, Barneveld A, van Weeren PR.Extracorporeal shockwave therapy (ESWT) has recently been introduced as a new therapy for tendon injuries in horses, but little is known about the basic mechanism of action of this therapy. Objective: To study the effect of ESWT on biochemical parameters and tenocyte metabolism of normal 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 ten...
Potter SJ, Bamford NJ, Harris PA, Bailey SR.To determine the prevalence of obesity within a population of pleasure horses and ponies in Victoria, Australia, and to compare owners' perceptions of their animals' body condition with researchers' assessments. Methods: An observational study plus owner questionnaire. Methods: Ten Pony Club rallies in different regions of Victoria were attended. Information regarding 229 horses and ponies were obtained from owner questionnaires, and owners' perceptions of the current body condition of their animals were assessed using a visual analogue scale. Body condition score (BCS) was assessed by the res...
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...
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 ...
Snow DH, Guy PS.Skeletal muscle of the equine was differentiated into three fibre types according to myosin ATPase (pH 9.4) and succinic dehydrogenase activity. The percentage of these types was determined in the musculus deltoideus, m triceps brachii caput longum, m gluteus medius, m semitendinosis, m biceps femoris and m vastus lateralis of the thoroughbred, Shetland pony, pony, heavy hunter and donkey. In addition the m gluteus medius was examined in the arab and American racing quarterhorse. High myosin ATPase activity fibres varied from a mean of 93.2 per cent in the m gluteus medius of the quarterhorse ...
Sarin JK, Te Moller NCR, Mancini IAD, Brommer H, Visser J, Malda J, van Weeren PR, Afara IO, Töyräs J.Arthroscopic assessment of articular tissues is highly subjective and poorly reproducible. To ensure optimal patient care, quantitative techniques (e.g., near infrared spectroscopy (NIRS)) could substantially enhance arthroscopic diagnosis of initial signs of post-traumatic osteoarthritis (PTOA). Here, we demonstrate, for the first time, the potential of arthroscopic NIRS to simultaneously monitor progressive degeneration of cartilage and subchondral bone in vivo in Shetland ponies undergoing different experimental cartilage repair procedures. Osteochondral tissues adjacent to the repair sites...
Lichtenstein DL, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) provides a uniquely dynamic system in which to study the mechanism and role of genomic variation in lentiviral persistence and pathogenesis. We have used a Shetland pony model of infection to investigate the association of specific long terminal repeat (LTR) and env gene genomic sequences with the initiation of infection and the onset of disease. We analyzed viral RNA isolated from a pathogenic stock of virus (EIAV PV) and from plasma taken during the first disease episode from two ponies infected with EIAV PV. Overall sequence variation within gp90 was lo...
Norton EM, Avila F, Schultz NE, Mickelson JR, Geor RJ, McCue ME.Ponies are highly susceptible to metabolic derangements including hyperinsulinemia, insulin resistance, and adiposity. Objective: Genetic loci affecting height in ponies have pleiotropic effects on metabolic pathways and increase the susceptibility to equine metabolic syndrome (EMS). Methods: Two hundred ninety-four Welsh ponies and 529 horses. Methods: Retrospective study of horses phenotyped for metabolic traits. Correlations between height and metabolic traits were assessed by Pearson's correlation coefficients. Complementary genome-wide analysis methods were used to identify a region of in...
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),...
Nyman G, Funkquist B, Kvart C, Frostell C, Tokics L, Strandberg A, Lundquist H, Lundh B, Brismar B, Hedenstierna G.The anatomical basis of gas exchange impairment in the anaesthetised horse was studied by computerised tomography (CT; three shetland ponies) and morphological analysis (one pony and three horses). By means of CT, densities were seen in dependent lung regions early during anaesthesia, both with spontaneous breathing and with mechanical ventilation. The densities remained for some time where they had initially been created when the animal was turned from dorsal to sternal recumbency. Deep insufflation of the lungs reduced the dense area. Gas exchange was impaired roughly in proportion to the de...
Metzger J, Rau J, Naccache F, Bas Conn L, Lindgren G, Distl O.Miniature size in horses represents an extreme reduction of withers height that originated after domestication. In some breeds, it is a highly desired trait representing a breed- or subtype-specific feature. The genomic changes that emerged due to strong-targeted selection towards this distinct type remain unclear. Results: Comparisons of whole-genome sequencing data from two Miniature Shetland ponies and one standard-sized Shetland pony, performed to elucidate genetic determinants for miniature size, revealed four synergistic variants, limiting withers height to 34.25 in. (87 cm). Runs of h...
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...
Reissmann M, Bierwolf J, Brockmann GA.In horses, a pigment dilution acting only on black eumelanin is the so-called silver coat colour, which is characterized by a chocolate-to-reddish body with a white mane and tail. Using information from other species, we focused our study on SILV as a possible candidate gene for the equine silver phenotype. A 1559-bp genomic fragment was sequenced in 24 horses, and five SNPs were detected. Two of the five SNPs (DQ665301:g.697A>T and DQ665301:g.1457C>T) were genotyped in 112 horses representing eight colour phenotypes. Both mutations were completely associated with the silver phenotype: all eum...
Rafati N, Andersson LS, Mikko S, Feng C, Raudsepp T, Pettersson J, Janecka J, Wattle O, Ameur A, Thyreen G, Eberth J, Huddleston J, Malig M, Bailey E....Skeletal atavism in Shetland ponies is a heritable disorder characterized by abnormal growth of the ulna and fibula that extend the carpal and tarsal joints, respectively. This causes abnormal skeletal structure and impaired movements, and affected foals are usually killed. In order to identify the causal mutation we subjected six confirmed Swedish cases and a DNA pool consisting of 21 control individuals to whole genome resequencing. We screened for polymorphisms where the cases and the control pool were fixed for opposite alleles and observed this signature for only 25 SNPs, most of which we...
Küls N, Trujanovic R, Otero PE, Larenza-Menzies MP.Colic surgery is one of the most painful procedures carried out in horses. Common strategies to alleviate immediate postsurgical abdominal pain include the administration of potent systemic analgesics; however, these may cause unwanted adverse effects such as cardiovascular depression, ileus, and ataxia. The administration of local anesthetics at the incision site in form of an ultrasound-guided subcostal transversus abdominis plane (TAP) block may therefore be preferred to provide adequate analgesia without significant side effects. To date, no technique for a TAP block in horses undergoing m...
Korthagen NM, Brommer H, Hermsen G, Plomp SGM, Melsom G, Coeleveld K, Mastbergen SC, Weinans H, van Buul W, van Weeren PR.Cartilage repair remains a major challenge and treatment of (osteo)chondral defects generally results in poor quality fibrous repair tissue. Our approach aims to address some of the major biomechanical issues encountered in scaffold-based cartilage repair, such as insufficient stiffness of the scaffolds, step formation at the interface with the native tissue and inadequate integration with the original tissue. Two osteochondral defects were created on the medial femoral trochlear ridge in each stifle of six Shetland ponies. The defects were filled with a bi-layered implant consisting of a poly...
Spoormakers TJP, Veraa S, Graat EAM, van Weeren PR, Brommer H.The importance of the equine thoracolumbar vertebral column in orthopaedic disorders is well recognized and diagnostic imaging becomes more feasible, but little is known about variations in the anatomical configuration within breeds. In this descriptive post-mortem study, anatomical variations in three widely differing breeds: Warmblood horses, Shetland ponies and semi-feral Konik horses are described. The caudal cervical (C), thoracic (T), lumbar (L) and sacral (S) regions of the vertebral column of 30 Warmblood horses, 29 Shetland ponies and 18 Konik horses were examined using computed tomog...
Kankofer M, Kolm G, Aurich J, Aurich C.Sperm cell membranes are susceptible to peroxidative damage by an excess of reactive oxygen species (ROS). Antioxidative defence systems consisting of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) physiologically control the balance between ROS production and neutralization. In the present study the hypothesis was tested that lipid peroxidation occurs during storage of semen at 5 degrees C and that semen extender has positive effects on the antioxidative potential of equine semen. The aim of the study was to determine the activity of GSH-Px, SOD and CAT and the...
Frischknecht M, Flury C, Leeb T, Rieder S, Neuditschko M.Shetland ponies were selected for numerous traits including small stature, strength, hardiness and longevity. Despite the different selection criteria, Shetland ponies are well known for their small stature. We performed a selection signature analysis including genome-wide SNPs of 75 Shetland ponies and 76 large-sized horses. Based upon this dataset, we identified a selection signature on equine chromosome (ECA) 1 between 103.8 Mb and 108.5 Mb. A total of 33 annotated genes are located within this interval including the IGF1R gene at 104.2 Mb and the ADAMTS17 gene at 105.4 Mb. These two ge...
van Grevenhof EM, Ducro B, Heuven HC, Bijma P.It is expected that climate and habitat factors influence the prevalence of culicoides and, therefore, the prevalence of insect bite hypersensitivity (IBH), but very little is described in the literature to prove the association of these factors. Prevalence varies widely from 3% in certain areas of Great Britain to 60% in certain parts of Australia. Objective: To describe the influence of environmental factors on the prevalence of IBH in Shetland ponies and Friesian horses in The Netherlands. Methods: Data on 3284 Shetland and 2824 Friesian mares (n = 6108) were collected in The Netherlands, b...
van Eldik P, van der Waaij EH, Ducro B, Kooper AW, Stout TA, Colenbrander B.Inbreeding is widely believed to negatively affect reproductive performance. Indeed, in some species, high levels of inbreeding are thought to be the major cause of poor semen quality. It is, however, not clear whether inbreeding affects fertility in horses. In this study, the relationship between inbreeding and semen quality was examined in 285 immature Shetland pony stallions submitted for breeding soundness examination in March-April of the years 1992-1997. The majority of stallions examined were 3 years old (85%) and their coefficients of inbreeding ranged from 0 to 25% (mean+/-S.D.: 3+/-4...
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), ...
