Topic:Longitudinal Study
A longitudinal study in the context of equine research involves the systematic observation and data collection from the same group of horses over an extended period. This research approach aims to track changes and developments in various health parameters, behaviors, or conditions within the equine population being studied. By repeatedly assessing the same subjects, researchers can identify patterns, establish temporal sequences, and infer potential causal relationships. Longitudinal studies in horses can encompass a wide range of topics, including growth and development, disease progression, and the impact of environmental or management changes. This page gathers peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and implications of longitudinal studies in equine science.
The use of sonoelastography to assess the recovery of stiffness after equine superficial digital flexor tendon injuries: A preliminary prospective longitudinal study of the healing process. The objective assessment of the mechanical properties of the superficial digital flexor tendon (SDFT) could provide useful information for the rehabilitation of horses with SDFT injuries. Assessment of strain ratio (the strain of a standard reference divided by that of lesions) is a quantitative method in sonoelastography for evaluating tissue stiffness in vivo. As yet, no longitudinal studies have used strain ratio to evaluate the progression of stiffness in SDFT injuries. Objective: To test the hypothesis that strain ratio can evaluate the recovery of stiffness during the healing of SDFT inj...
Monitoring training response in young Friesian dressage horses using two different standardised exercise tests (SETs). Most Friesian horses reach their anaerobic threshold during a standardized exercise test (SET) which requires lower intensity exercise than daily routine training. Objective: to study strengths and weaknesses of an alternative SET-protocol. Two different SETs (SETA and SETB) were applied during a 2 month training period of 9 young Friesian dressage horses. SETB alternated short episodes of canter with trot and walk, lacking long episodes of cantering, as applied in SETA. Following parameters were monitored: blood lactic acid (BLA) after cantering, average heart rate (HR) in trot and maximum H...
Duodenojejunal mesenteric rents: Survival and complications after surgical correction in 38 broodmares (2006-2014). To describe short-term and long-term survival of horses with duodenojejunal mesenteric rents, and to examine the association of selected preoperative, intraoperative, and postoperative factors with survival or colic after discharge, in horses with duodenojejunal mesenteric rents. Methods: Retrospective case series. Methods: Horses undergoing surgery for correction of small intestinal lesions secondary to duodenojejunal mesenteric rents (n = 38). Methods: Medical records (2006-2014) of horses admitted to a referral hospital in Kentucky were reviewed. Data for preoperative and intraoperative...
Presence and distribution of yeasts in the reproductive tract in healthy female horses. Yeasts are commensal organisms found in the reproductive and gastrointestinal tracts, and on the skin and other mucosa in mammals. Objective: The purpose of this study was to isolate and identify yeast flora in the caudal reproductive tract in healthy female horses. Methods: Longitudinal study. Methods: A total of 453 samples were collected using double-guarded swabs from the vestibule, clitoral fossa and vagina in 151 horses. All samples were cultured on Sabouraud 4% dextrose agar and incubated at 35°C for 7-10 days. Isolates were identified according to their morphological characteristics a...
Longitudinal changes in serum catecholamines, dopamine, serotonin, ACTH and cortisol in pregnant Spanish mares. Systemic physiological changes required for placental and fetal development during pregnancy are associated with an activation of the sympathetic nervous system (SNS) and the hypothalamus-pituitary-adrenal axis (HPA) in women, but this fact has not been investigated in mares. Venous blood samples were taken monthly from 31 successful Spanish mares during the 11months of pregnancy. During the first 4months of pregnancy, adrenaline (AD), dopamine (DOPA) and ACTH increases, whereas 5-hydroxitryptamine (5-HT) decreased, and noradrenaline (NAD) and cortisol (CORT) did not change. Serum NAD increase...
Long-term follow-up on recovery, return to use and sporting activity: a retrospective study of 236 operated colic horses in Finland (2006-2012). Surgical treatment of colic is expensive and complications may occur. Information on the prognosis and the use of the horse after surgery for colic is important for surgeons and owners. Current literature on return to athletic function after celiotomy is limited. The present study reviewed surgical cases of the Veterinary Teaching Hospital, Helsinki, Finland for 2006-2012. The aim was to follow the population of horses of different breeds for surgical findings, postsurgical complications, long-term recovery and prognosis. The findings and their influence on survival, return to previous or inte...
The development of locomotor kinetics in the foal and the effect of osteochondrosis. Foals stand and walk immediately after birth, but insight into the subsequent longitudinal development of their gait kinetics in the early juvenile phase and the possible influence of osteochondrosis thereon is lacking. Objective: To quantify gait kinetics in foals during the first half year of life, taking into account their osteochondrosis status. Methods: Prospective, cohort study performed at a single stud farm. Methods: Pressure plate measurements at walk and trot from 11 Dutch Warmblood foals during the first 24 weeks of life were used to determine body mass normalised peak vertical forc...
Pro-inflammatory cytokines and structural biomarkers are effective to categorize osteoarthritis phenotype and progression in Standardbred racehorses over five years of racing career. Joint impact injuries initiate a progressive articular damage finally leading to post-traumatic osteoarthritis (PTOA). Racehorses represent an ideal, naturally available, animal model of the disease. Standardbred racehorses developing traumatic osteoarthritis of the fetlock joint during the first year of their career were enrolled in our study. Age-matched controls were contemporarily included. Biomarker levels of equine osteoarthritis were measured in serum and synovial fluid (SF) at baseline, and repeated yearly over the next 4 years of training (from T1 to T4). The effect of time and disea...
Improved radiological diagnosis of palmar osteochondral disease in the Thoroughbred racehorse. Palmar osteochondral disease (POD) is common in the Thoroughbred racehorse yet difficult to diagnose by radiography alone. Objective: To improve the sensitivity and specificity for diagnosing POD from radiographs. Methods: Prospective, longitudinal study. Methods: Radiographs in nine different projections were made of metacarpophalangeal joints (MCPJ) of 50 Thoroughbreds. Post-mortem, MCPJs were dissected and gross pathology was scored. Three experienced Thoroughbred clinicians read each radiograph and recorded their findings. Another clinician reviewed each radiograph alongside the related gr...
Heritability and factors associated with number of harness race starts in the Spanish Trotter horse population. Longevity/durability is a relevant trait in racehorses. Genetic analysis and knowledge of factors that influence number of harness race starts would be advantageous for both horse welfare and the equine industry. Objective: To perform a genetic analysis on harness racing using number of races as a measure of longevity/durability and to identify factors associated with career length in Spanish Trotter Horses (STH). Methods: Longitudinal study. Methods: Performance data (n = 331,970) on the STH population for harness racing at national level between 1990 and 2014 were used. A grouped data model ...
Acute and chronic infections with nonprimate hepacivirus in young horses. The recently discovered nonprimate hepacivirus (NPHV) naturally infects horses and is the closest known homolog of hepatitis C virus to date. Within a follow-up study acute field infections were monitored in four young Thoroughbred horses until the ages of 12-13 months. Serum samples were analyzed for the presence of NPHV RNA and anti-NPHV NS3 antibodies and liver specific parameters were evaluated. The four young horses were not able to clear infection, but remained chronically infected for the entire monitored time period despite the presence of NPHV specific antibodies.
Low-Field Magnetic Resonance Imaging Appearance of Postarthroscopic Magnetic Susceptibility Artifacts in Horses. An awareness of magnetic susceptibility artifacts is important for interpreting prepurchase and postoperative magnetic resonance imaging (MRI) studies in horses. These artifacts occur when a metallic or a paramagnetic substance creates a local magnetic field deformity. Aims of the current experimental study were to determine prevalence of these artifacts after arthroscopy in a sample of nonlame horses, and to describe effects of time and type of pulse sequence on low-field MRI signal intensity and detection of the artifacts. Ten, nonlame Standardbred horses were prospectively recruited. All ho...
Duration of serum antibody response to rabies vaccination in horses. OBJECTIVE To investigate the impact of age and inferred prior vaccination history on the persistence of vaccine-induced antibody against rabies in horses. DESIGN Serologic response evaluation. ANIMALS 48 horses with an undocumented vaccination history. PROCEDURES Horses were vaccinated against rabies once. Blood samples were collected prior to vaccination, 3 to 7 weeks after vaccination, and at 6-month intervals for 2 to 3 years. Serum rabies virus-neutralizing antibody (RVNA) values were measured. An RVNA value of ≥ 0.5 U/mL was used to define a predicted protective immune response on the b...
Synovial incorporation of polyacrylamide hydrogel after injection into normal and osteoarthritic animal joints. Polyacrylamide hydrogel (PAAG) is a non-toxic, non-degradable synthetic product, used for years in the augmentation of soft tissues. Preliminary results in animals and humans have suggested long-lasting beneficial effects on symptoms of osteoarthritis (OA). The aim of this histopathological study was to investigate whether intra-articular injection of PAAG is integrated into synovial tissue in normal and OA animal joints, and if this integration is sustained. (A) A prospective, controlled, longitudinal study of normal knee joints injected with PAAG was performed in 10 rabbits, following the an...
Measurement of distal limb sub-bandage pressure over 96 hours in horses. Currently, there is no objective information quantifying pressures exerted by distal limb bandages. Objective: To quantify the pressure exerted by each compression layer, a polo wrap (DLP), a compression bandage (DLC), and to measure the effect of time on sub-bandage pressure. Methods: Longitudinal observational experiment. Methods: A DLC construct included a cotton roll compressed with brown gauze and elastic layers and the DLP construct included a pillow pad compressed by a cloth wrap. Dorsal and lateral sensors were placed on the mid-metacarpus. In healthy horses, sub-bandage pressures were...
Preventive health care of Pony Club horses in rural New South Wales, Australia. To describe preventive health care provided to a cohort of Pony Club horses in rural New South Wales, Australia, and the associated veterinary involvement. Methods: Prospective longitudinal study Methods: Observational data collected for 48 Pony Club horses using daily owner-kept diaries and monthly veterinary visits for 9-12 months. Results: Frequency of healthcare events varied markedly between the horses; 54% of horses received 5 or more foot-care treatments, 69% received 1-3 anthelmintic treatments, 40% received dental care, 21% received chiropractic care; only 8% were vaccinated. Farriers...
Clinical course of sarcoids in 61 Franches-Montagnes horses over a 5-7 year period. The progression of equine sarcoids (ES) is notoriously unpredictable. Making a choice for the appropriate treatment is challenging when dealing with milder manifestations of ES. Objective: The aim of this study was to investigate the clinical course of ES in young horses. Methods: A cohort of 61 ES-affected three-year-old Franches-Montagnes horses and a breed-, age- and geographically matched control group of 75 ES-free peers were examined twice over a period of 5-7 years. Owners and caretakers were queried, using a standardized questionnaire. Results: More than half of the 38/61 (62%) horses...
Pharmacokinetic and pharmacodynamic properties of pergolide mesylate following long-term administration to horses with pituitary pars intermedia dysfunction. The objective of this study was to gain an understanding of the pharmacokinetic and pharmacodynamic properties of pergolide in horses with PPID after of long-term oral administration. Six horses with confirmed PPID were treated with pergolide (Prascend ) at 1 mg/horse po q24 h for 2 months, followed by 2 mg/horse po q24 h for 4 months. Following the last dose, plasma samples were collected for measurement of pergolide using an LC/MS/MS method and ACTH measurement using a chemiluminescent immunoassay. Noncompartmental and compartmental pharmacokinetic analyses were performed, as well as p...
Nonlinear hierarchical modeling of experimental infection data. In this paper, we propose a nonlinear hierarchical model (NLHM) for analyzing longitudinal experimental infection (EI) data. The NLHM offers several improvements over commonly used alternatives such as repeated measures analysis of variance (RM-ANOVA) and the linear mixed model (LMM). It enables comparison of relevant biological properties of the course of infection including peak intensity, duration and time to peak, rather than simply comparing mean responses at each observation time. We illustrate the practical benefits of this model and the insights it yields using data from experimental i...
Long-term monitoring of opioid, sedative and anti-inflammatory drugs in horse hair using a selective and sensitive LC-MS/MS procedure. Compared to blood or urine, drugs can be detected for much longer periods in the long hair of horses. The aim of this study was to establish and validate a highly sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the detection and quantification of frequently prescribed opioids, sedatives and non-steroidal anti-inflammatory agents in the mane and tail hair of horses. Based on an average growth rate of about 2 cm per month, times of administration reported by horse owners or veterinary physicians were related to drug localizations in hair. Hair samples were collecte...
The repeatability of an oral glucose test in ponies. Insulin dysregulation can be difficult to diagnose from basal insulin and glucose concentrations, so a field-based oral glucose test (OGT) is preferred. However, the repeatability of this test has not been reported. Objective: To determine the repeatability of an in-feed OGT in ponies and examine some factors affecting the palatability of the test meal. Methods: A repeated measures, longitudinal study. Methods: An in-feed OGT was performed at 08.00 h on 3 consecutive occasions under controlled conditions in 8 mixed breed ponies. d-glucose (0.75 g/kg bwt) was dissolved in water and combined wit...
Arthroscopic Removal of Large Extensor Process Fragments in 18 Friesian Horses: Long-Term Clinical Outcome and Radiological Follow-Up of the Distal Interphalangeal Joint. Report long-term clinical and radiological follow-up in horses after removal of large extensor process fragments occupying >25% of the joint surface of the distal interphalangeal joint (DIJ). Methods: Retrospective case series. Methods: Friesian horses (n=18) that underwent arthroscopic removal of a large extensor process fragment. Methods: Arthroscopic examination of the DIJ was performed in dorsal recumbency with the affected foot in extension using routine portals. Visualization of the fragment was improved using motorized synovial resectors. A dissection plane between the common digital ex...
Impact of feeding and housing on the development of osteochondrosis in foals-A longitudinal study. Osteochondrosis dissecans (OCD) is a developmental orthopedic disease caused by a failure of the endochondral ossification in epiphyseal plates and joint cartilage. This trouble may induce the presence of osteochondral fragments in the articulation, fissures or subchondral bone cysts in the growth cartilage. Occurrence of osteochondrosis is influenced by a complex interaction of different factors. Among these, the effect of the housing and the feeding of the foals during their first months of life, have been described as risk factors for the development of osteochondrosis. The aim of this stud...
Changes in maternal androgens and oestrogens in mares with experimentally-induced ascending placentitis. While advanced stages of ascending placentitis can be diagnosed by transrectal ultrasonography and clinical signs, early stages can be missed. Thus, additional tools could enhance assessment of placental health. Objective: To characterise peripheral dehydroepiandrosterone sulphate (DHEA-S) and testosterone concentrations in mares carrying normal pregnancies (Study 1) and compare plasma concentrations of DHEA-S, testosterone, oestradiol 17-β (oestradiol) and oestrone sulphate (OES) in mares with or without placentitis (Study 2). Methods: Longitudinal cohort study of healthy mares (Study 1) and...
The incidence and risk factors for shipping fever in horses transported by air to Hong Kong: Results from a 2-year prospective study. A 2 year prospective study was performed between February 2011 and January 2013 to determine the incidence and risk factors for shipping fever (SF) in horses transported by air to Hong Kong (HK). Using a questionnaire, data were collected from professional flying grooms regarding the journey to HK and horses in the shipment. Horses were monitored in quarantine for 2 weeks after arrival in HK, and clinical signs of SF recorded. Poisson and logistic regression models were used to identify risk factors for SF at the horse and shipment levels. The study analysed data from 869 horses on 81 flights ...
Environmental heat and airborne pollen concentration are associated with increased asthma severity in horses. Clinical exacerbations of severe equine asthma (formerly recurrent airway obstruction [RAO]) are more frequently reported during winter when horses are exposed to airborne dusts during stabling. However, we have also observed a worsening of clinical signs on days during a heatwave. Objective: To investigate the association between environmental temperature and humidity and clinical signs of asthma in horses during clinical exacerbation of the disease. Methods: Retrospective longitudinal study. Methods: Historical data on 14 severe asthmatic horses exposed to a dusty environment and evaluated u...
Factors associated with dust dispersed in the air of indoor riding arenas. Environmental factors contribute to respiratory diseases in horses and man. During exercise, equine ventilation is increased, potentially increasing exposure of the airways to inhaled particulates. Currently, there is very little information on the quality of air in riding arenas. Objective: To evaluate air quality and dust particle concentrations in indoor riding arenas before and after use for riding. Methods: Longitudinal study. Methods: Air quality was assessed in 4 indoor riding arenas in Saxony-Anhalt, Germany on a monthly basis for 1 year. Concentrations of particles in 6 particle fract...
Longitudinal Cell Tracking and Simultaneous Monitoring of Tissue Regeneration after Cell Treatment of Natural Tendon Disease by Low-Field Magnetic Resonance Imaging. Treatment of tendon disease with multipotent mesenchymal stromal cells (MSC) is a promising option to improve tissue regeneration. To elucidate the mechanisms by which MSC support regeneration, longitudinal tracking of MSC labelled with superparamagnetic iron oxide (SPIO) by magnetic resonance imaging (MRI) could provide important insight. Nine equine patients suffering from tendon disease were treated with SPIO-labelled or nonlabelled allogeneic umbilical cord-derived MSC by local injection. Labelling of MSC was confirmed by microscopy and MRI. All animals were subjected to clinical, ultrason...
Development of the faecal microbiota in foals. The intestinal microbiota is a complex polymicrobial ecosystem that exerts extremely important roles in the development and maintenance of health. Recently, as new sequencing technologies have become more available, there has been a revolution in the understanding of the equine intestinal microbiota. However, studies characterising the pioneer intestinal bacteria colonising foals and its development over time are still limited. Objective: The objectives of this study were to characterise the intestinal bacterial colonisation of newborn foals and to follow individual animals over time until age...
The longitudinal effect of a multi-strain probiotic on the intestinal bacterial microbiota of neonatal foals. The microbiota plays a key role in health and disease. Probiotics are a potential way to therapeutically modify the intestinal microbiota and prevent disease. Objective: The aim of this study was to investigate the effects of probiotics on the bacterial microbiota of foals during and after administration. Methods: Randomised placebo controlled field trial. Methods: Thirty-eight healthy neonatal foals enrolled in a previous study were selected. The foals had received a multi-strain probiotic (four Lactobacillus spp. 3-4 × 10 colony-forming units (cfu)/g each, Bifidobacterium animalis spp. lact...