Older Horses Research Articles

Girth to Height Ratio (GHR) is Inversely Correlated to Plasma Glucose to Insulin Ratio (GIR), a Measurement of Insulin Resistance, in Horses

Insulin resistance, most often caused by obesity and associated with increased age, occurs when insulin‐dependent tissues have a diminished sensitivity to the effects of insulin. In horses, insulin resistance increases the risk for developing a severe lameness condition, laminitis. The aim of this study was to determine if accessible external measurements of obesity could facilitate detection of insulin resistance in horses, possibly preventing the onset of laminitis through early intervention. We hypothesized that the progression of insulin resistance would directly correlate with quantitative assessment of physical parameters of obesity, such as body condition score (BCS), girth to height ratio (GHR), and neck circumference to height ratio (NCHR). Insulin resistance was determined by fasting plasma glucose to insulin ratio (GIR) in horses (n=23) of varying body conditions. GIR was inversely correlated to age (p = 0.003) and GHR (p = 0.048). There was no relationship between GIR and BCS or NCHR. As the quantitative measurement of GIR is inversely correlated to insulin resistance, these results indicate that older horses and those with greater GHR were more likely to be insulin resistant. In conclusion, GHR predicts insulin resistance as determined by GIR, but other physical parameters of obesity, such as the subjective assessment of BCS and the objective measurement of NCHR, are not reliable predictors of insulin resistance. Therefore, GHR could be used as a parameter to indicate if further assessment of insulin resistance should be conducted in individual horses.

Prevalence of dental disorders in an abattoir population of horses in South Africa by oral examination of intact and bisected heads

Dental care is an integral part of equine veterinary practice. The objectives of this cross sectional study were to describe the prevalence of dental disorders in an abattoir population of horses, and to compare oral examination of intact and bisected heads. Heads from 40 horses, 19 males and 21 females, were examined and divided into immature, adult or older horses based on dental age.Older horses had a significantly higher prevalence of infundibular caries (91.7%), diastemata (66.7%) and fractures (58.3%), whereas dental wear disorders affected all age groups. Gasterophilus spp. larvae were detected in 20% of the horses. A short oral examination performed on intact heads was adequate for diagnosing major disorders, but the occurrence of many conditions had only fair to poor agreement with the bisected heads. A more detailed oral examination may be needed for reliable diagnosis of many disorders.

Seroprevalence of Toxoplasma gondii and Neospora spp. Infections in Arab Horses, Southwest of Iran.

Background:Because of the economic importance of the Arab race horses and also the role of Toxoplasma gondii and Neospora spp. in abortion and reproductive failure of these animals, we decided to perform this study.Objectives:We designed this study to investigate the seroprevalence of anti-Toxoplasma gondii and anti-Neospora spp. antibodies in Arab horses from 12 cities of Khuzestan province in southwest of Iran.Materials and Methods:From October 2009 to March 2011, a total of 235 blood samples were collected from jugular veins of Arab horses of different ages and genders from 12 cities of Khuzestan province. All the sera were tested for anti-Toxoplasma antibodies using the modified agglutination test (MAT) and the existence of anti-Neospora antibodies were tested using N-MAT for Neospora spp.Results:According to the MAT results, antibodies to T. gondii were found in 114 (48.5%) of 235 sera with titers of 1:20 in 84, 1:40 in 19, 1:80 in four, 1:160 in four, and 1:320 in three horses. According to the N-MAT results, antibodies to Neospora spp. were found in 47 (20%) of 235 sera with titers of 1:40 in 39, 1:80 in five, and 1:160 in three horses. We did not observe any statistically significant differences regarding age groups and genders between seropositive and seronegative horses for Neospora spp. using chi-square (χ2) test, but it seemed that anti-Toxoplasma antibodies were more prevalent in older horses (≥ 10 years old).Conclusions:The results indicated that Arab horses are exposed to these parasites in southwest of Iran. Further research is required to determine the genomic structures of these parasites in Arab horses in southwest of Iran.

Age-dependent expression of osteochondrosis-related genes in equine leukocytes

Introduction: Osteochondrosis (OC) is a developmental disease in horses which has a significant impact on the horse's welfare and performance. The early disturbance in the process of endochondral ossification progresses...

Musculoskeletal lesions and lameness in 121 horses with carpal sheath effusion (1999-2010).

Equine carpal sheath effusion has multiple etiologies. The purpose of this retrospective study was to describe the prevalence of distinct musculoskeletal lesions lameness in a sample of horses with a clinical diagnosis of carpal sheath effusion. A total of 121 horses met inclusion criteria. Seventy-four percent (89/121) of horses were lame at presentation; middle-aged (9-18 years, 80%) and older (> 18 years, 85%) horses were lame more frequently than young horses (< 9 years, 44%). Ninety-three percent (113/121) were diagnosed with osseous and/or soft tissue abnormalities. Of these 113 horses, 10 exhibited osseous abnormalities, whereas 111 were diagnosed with soft tissue lesions. Eighty-four percent (93/111) of the soft tissue injuries extended from the caudodistal antebrachium to the palmar metacarpus. The superficial digital flexor tendon (98/111; 88%) and accessory ligament of the superficial digital flexor tendon (64/111; 58%) were the most commonly injured structures, with both structures affected in 41 (41/111; 37%) horses. Injuries within the caudodistal antebrachium included the superficial digital flexor musculotendinous junction (66), the accessory ligament of the superficial digital flexor tendon (64), and deep digital flexor muscle (21), in isolation or in combination with other structures. Increased echogenicity in the medial superficial digital flexor musculotendinous junction was detected in 40 horses and was significantly associated with increasing age (middle-aged, 19/40; old, 18/40). Findings from this study indicated that age should be taken into consideration for horses presented with carpal sheath effusion and that adjacent structures within the caudodistal antebrachium should be included in evaluations.

Suspensory ligament degeneration associated with pituitary pars intermedia dysfunction in horses

In older horses, pituitary pars intermedia dysfunction (PPID) and suspensory ligament (SL) degeneration are common. The aim of the present study was to identify histopathological changes in the SL in horses with PPID. SLs of four horses with clinical signs of PPID (17–26 years of age) were compared with SLs from four old horses (18–31 years of age) and three young horses (4–9 years of age). In horses with PPID, there was reduced longitudinal arrangement of collagen fibres in SLs, along with inclusions of cartilage, extracellular matrix and haemorrhage, as well as significant proteoglycan accumulations between SL fibres. These changes are similar to the degeneration of connective tissues in Peruvian Paso horses with SL degeneration and in humans with Cushing's disease or after long term high dose corticosteroid treatments. These findings indicate an association between degeneration of the SL and PPID.

Prevalence of Osseous Pathology in the Articular Process Articulations in the Equine Cervical and Cranial Thoracic Vertebrae

Reasons for performing studyOsteoarthritis (OA) of the articular processes (APs) is recognised as a clinical condition in the equine cervical spine, but there is little information on the prevalence and distribution of OA in the APs of the cervical and cranial thoracic vertebrae.ObjectivesTo determine the prevalence and distribution of OA in the APs of the equine cervical and cranial thoracic vertebrae in relation to vertebral level, age and size of the horse and side of the neck.Study designA post mortem longitudinal randomised study of 53 horses.HypothesesOA is more prevalent and more severe in the APs of the cervicothoracic junction, the prevalence and severity of OA increases with horse age and size, and OA is equally distributed on left and right sides.MethodsThe cervical (C1–C7) and cranial thoracic (T1–T7) vertebrae of 53 horses were removed at necropsy and boiled out. Based on the size (percentage) of the joint margin that was affected, OA of the 4 APs of each vertebra was graded on a scale of 0 (no osseous lesions) to 3 (severe osseous lesions). Based on these grades, a 3‐factor ANOVA was used to test the random effects of horse, age (young, old) and size (small, large), and the fixed factors of side (left, right) and vertebral level (C1 to T7).ResultsOA lesions were most severe in the mid‐cervical vertebrae (C3–C4) followed by the cervicothoracic curvature (C5–T1). Severity of OA increased with age and size of the horse but there was no difference between left and right sides.ConclusionsOA is symmetrically present with higher severity in the mid‐cervical and cervicothoracic regions and with higher prevalence in older and larger horses. These factors support bilateral injections in specific APs for clinical treatment of OA in the equine cervical spine.Ethical animal research: Approval for this study was obtained under Institutional Animal Care and Use Committee number 02‐11/020‐00. Explicit owner informed consent for participation in this study was not stated but general permission for post mortem examination was given. Sources of funding: Supported by the CVM Endowed Research Funds and the McPhail Endowment at Michigan State University. Competing interests: None.

Profiles of strongyle EPG values for Thoroughbred mares on 14 farms in Kentucky (2012–2013)

The main purpose of the research was to determine if three weekly samplings would produce consistent results for low strongyle egg shedders, generally associated with older horses. Strongyle egg counts per gram of feces (EPG) were done for 661 Thoroughbred mares on 14 farms in 2012–2013 once a week for three consecutive weeks. None of the mares had been treated with ivermectin or moxidectin for more than 90 days and with fenbendazole, oxibendazole, or pyrantel pamoate for more than 60 days. Strongyle EPG count data indicated that 38.3% of the mares were positive at first and second sampling, and 37.8% – at third sampling. There were 5.6–63.3% of horses positive per farm. Correlations between EPG count data in all three weeks are quite high (Rs=0.84, p<0.001). Level of horse infection was found to be dependent on horse age, type of farm and individual characters of horse. This study documented that strongyle egg counts (EPGs) from individual horses did not differ significantly between weeks. Thus, a single strongyle EPG count can be interpreted as indicative of the level of egg shedding for a given horse. These data support the current trend of not deworming all adult horses on a farm, so that high shedders can be identified and treated. This saves horse owners money and reduces development of potential drug resistance of parasites because of less frequent usage of antiparasitic compounds. Information from this study helps to conclude recommendations for parasite control in horses globally.

Repeatability of kinematics traits of free jumping in Brazilian sport horses

This study was carried out to estimate the repeatability of kinematics traits associated to the performance of free jumping young horses at three different ages. Free jumpings from 108 young horses were evaluated, resulting in a total of 1067 jumpings. All the animals were assessed at three age classes, at 22–25; 29–32 and 36–39 months of age, with five free jumping at each age classes over 0.60m, 0.80m and 1.05m high a vertical fence, respectively. Eighteen horse׳s anatomical points were highlighted by reflective markers. Jumpings were recorded by a 100-Hz camera and analyzed by the Simi Reality Motion Systems® software. The repeatability ranged from 0.18 to 0.89 at the three age classes. The lowest repeatability value was obtained for the radial-metacarpal angle at 22–25 months of age, as well as, the highest repeatability value was obtained for the coxofemoral angle at 36–39 months of age. In general, the repeatability values were lower at the first age class, with younger animals and the obstacle was lower, and higher repeatability values at the last evaluation, with higher fence and older horses had already twice performed the experimental protocol. The highest repeatability values were obtained for the horse-conformation traits measured at the trunk. Scapulohumeral angle, coxofemoral angle, neck angle and landing distance required fewer jumpings for young horses׳s jumping ability, where other traits, such as last stride length prior to jumping, forelimbs heights at jumping and radial-metacarpal angle, required additional measurements.

Chronisch progressief lymfoedeem bij het Belgisch trekpaard in België: klinische fenotypering, prevalentie en analyse van risicofactoren

Het Belgisch trekpaard is belast met chronisch progressief lymfoedeem (CPL), een bekende, ongeneeslijke aandoening. Tot op heden bestaat er geen uniform diagnostisch protocol, waardoor een goede schatting van de prevalentie onbestaande is. Het doel van dit artikel was een eenduidige klinische onderzoeksmethode te ontwikkelen om de objectiviteit van de CPL-diagnose te verhogen en de prevalentie van CPL bij het Belgisch trekpaard na te gaan. Daarnaast werd aan de hand van statistische modellen het verband onderzocht tussen bepaalde factoren, zoals de interactie leeftijd-geslacht, vachtkleur en seizoen, enerzijds en het optreden van klinische symptomen anderzijds. Deze studie toont aan dat de prevalentie van CPL hoog is. In de volledige steekproef, waarbij een groot aandeel van de paarden jonger was dan drie jaar, was 60,66% aangetast. In een subset van oudere dieren (≥ 3 jaar) was dat 85,86%. Bij sommige paarden werden reeds milde symptomen gezien vanaf één jaar (14% van de jaarlingen), maar duidelijke letsels kwamen doorgaans voor vanaf de leeftijd van drie jaar. Het ontwikkelde protocol kan de CPL-diagnose en toekomstige gegevensverzameling vergemakkelijken. In de voorliggende studie werden factoren die significant geassocieerd zijn met CPL, i. e. interactie leeftijd-geslacht, vachtkleur en seizoen, geïdentificeerd en gekwantificeerd. Daarmee is de basis gelegd voor kwantitatief genetisch onderzoek met als ultiem doel CPL bij het Belgisch trekpaard te reduceren.

Random regression models for genetic evaluation of performance of the Hungarian show-jumping horse population

The aim of the study was to estimate genetic parameters for show-jumping competition performance using random regression model. Show-jumping competition results collected between 1996 and 2009 were analyzed. The database contained 272 951 starts of 8020 horses. Identity number and gender of the horse, rider, competition date, the level of the competition and placing were recorded in the database. Competition levels were categorized into five groups. Weighted – competition level used – square root transformed placing was used to measure performance of horses. The random regression model included fixed effects for gender, year and place of competition, and random effects for rider, animal and permanent environment.&#x0D; Later performance of show-jumping horses measured with weighted square root ranks is less influenced by rider and permanent environmental effects than performance at the beginning of a horse’s sporting career. Heritability increased continuously from 6.3 years of age (2296 age in days), values were in the range of 0.07 and 0.37. Higher heritability was found in later ages. Weak genetic and phenotypic correlation was found between the early 4–5–6 years of age and older (7, 8, 8+) age classes. From 8.5 years of age (3132 days old) there were strong genetic and phenotypic correlations between neighboring age groups. For the same age classes moderate and strong genetic and phenotypic correlation was found. Genetic correlation between 13.5 years of age and older horses was very strong.

Effects of age and macrophage lineage on intracellular survival and cytokine induction after infection with Rhodococcus equi

Rhodococcus equi, a facultative intracellular pathogen of macrophages, causes life-threatening pneumonia in foals and in people with underlying immune deficiencies. As a basis for this study, we hypothesized that macrophage lineage and age would affect intracellular survival of R. equi and cytokine induction after infection. Monocyte-derived and bronchoalveolar macrophages from 10 adult horses and from 10 foals (sampled at 1–3 days, 2 weeks, 1 month, 3 months, and 5 months of age) were infected ex vivo with virulent R. equi. Intracellular R. equi were quantified and mRNA expression of IL-1β, IL-4, IL-6, IL-8, IL-10, IL-12 p40, IL-18, IFN-γ, and TNF-α was measured. Intracellular replication of R. equi was significantly (P<0.001) greater in bronchoalveolar than in monocyte-derived macrophages, regardless of age. Regardless of the macrophage lineage, replication of R. equi was significantly (P=0.002) higher in 3-month-old foals than in 3-day old foals, 2-week-old foals, 1-month-old foals, and adult horses. Expression of IL-4 mRNA was significantly higher in monocyte-derived macrophages whereas expression of IL-6, IL-18, and TNF-α was significantly higher in bronchoalveolar macrophages. Induction of IL-1β, IL-10, IL-12 p40, and IL-8 mRNA in bronchoalveolar macrophages of 1–3-day old foals was significantly higher than in older foals or adult horses. Preferential intracellular survival of R. equi in bronchoalveolar macrophages of juvenile horses may play a role in the pulmonary tropism of the pathogen and in the window of age susceptibility to infection.

Physiological response to a breed evaluation field test in Icelandic horses

This study examined the response in terms of heart rate (HR), respiratory rate (RR), haematocrit (Htc), rectal temperature (RT), and some plasma variables in Icelandic horses of different sexes and ages performing the riding assessment in a breed evaluation field test (BEFT). The study was conducted in Iceland on 266 horses (180 mares and 86 stallions, divided into four age groups; 4, 5, 6 and ⩾7 years old). RT and RR were recorded and blood samples were taken before the warm-up and after the riding assessment. Horse HR, velocity and distance were recorded during the warm-up, the riding assessment and a 5-min recovery period. The distance covered in the BEFT was 2.9±0.4 km (range: 1.8 to 3.8 km, n=248), the duration was 9:37±1:22 min:s (range: 5:07 to 15:32 min:s, n=260) and the average speed was 17.8±1.4 km/h (range: 13.2 to 21.3 km/h, n=248). Average HR was 184±13 b.p.m. (range: 138 to 210 b.p.m., n=102) and peak HR 224±9 b.p.m. (range: 195 to 238 b.p.m., n=102), and 36% of the BEFT was performed at HR ⩾200 b.p.m. Post-exercise plasma lactate concentration (Lac) was 18.0±6.5 mmol/l (range: 2.1 to 34.4 mmol/l, n=266), and there was an increase in total plasma protein, plasma creatine kinase and aspartate amino transferase concentration, as well as RR, RT and Htc. Stallions covered a longer total distance (in the warm-up and BEFT) (P<0.05), at a faster speed during BEFT (P<0.001) than mares and had higher Htc and lower HR and post-exercise Lac values. There were few effects of age, but the 4- and 5-year-old horses had lower Htc than older horses and 4-year-old horses had higher post-exercise RR than older horses, although they were ridden for a shorter distance, shorter duration and at lower peak velocity (P<0.1). The results showed that the riding assessment in the BEFT is a high-intensity exercise. The results also showed that aerobic fitness was higher in stallions and that age had a limited effect on the physiological response. It is suggested that these results should be used as a guide for the development of training programmes and fitness tests in Icelandic horses that would improve both performance and welfare of the horse.

High Plasma Concentrations of Sclerostin, an Inhibitor of the Wnt Signaling Pathway, in Young Horses Affected by Osteochondrosis

Osteochondrosis (OC) is a developmental disease in horses with a significant impact on the horse’s welfare and performance. The early disturbance of enchondral ossification progresses to inflammatory and healing process in older horses. Metabolic pathway analysis showed an obvious dysregulation of several signaling pathways related to cartilage formation and cartilage repair such as Wnt/β-catenin, Indian hedgehog and TGF-β signaling pathways. Other regulated genes appeared to be involved in high carbohydrate diet, abnormal insulin metabolism or inflammation. Sclerostin is an osteocyte-secreted soluble antagonist of the Wnt/β-catenin signaling pathway. It is crucial for osteoblast development and activity and is increased in naturally occurring lesions of equine osteochondrosis. The aim of this study is to compare the circulating sclerostin levels between OC-affected (n = 20) and healthy horses (n = 19). A significant linear regression between plasma sclerostin and age is observed especially in the healthy young horses. The mean plasma sclerostin concentration is significantly higher in young horses suffering from osteochondrosis compared to the control horses. These results reinforce the possible role of the Wnt/β-catenin signaling pathway in the OC pathogeny. The inhibition of this essential pathway could disturb the osteo-chondral differentiation. More studies are currently needed to define the eventual clinic interest of plasma sclerostin as future biomarker in bone and cartilage diseases.

Influence of age and sexual maturation on the expression of LH and FSH receptors and aromatase P450 in equine male reproductive tissues

Testicular function and maturation in male domestic animals is regulated by a complex interplay of endocrine, paracrine and autocrine factors. The objective of the present study was to characterize gene expression of the receptors for LH (LHR) and FSH (FSHR) as well as aromatase in equine epididymal and testicular tissue with regard to sexual maturity of stallions. We hypothesized tissueand age-related differences in the expression and localization of these genes. Tissue from testis and epididymis (corpus and cauda) was collected at routine castration of 21 sexually healthy stallions. They belonged to 4 different age groups: prepubertal ( 9 years, n 1⁄4 4). Changes in mRNA expression and protein localisation of LHR, FSHR and aromatase were analysed using quantitative real-time PCR (qRT-PCR) with GAPDH as reference gene, immunohistochemistry (IHC), and multiple immunofluorescence labelling. Statistical analysis was performed with the SPSS/PC statistics package (version 17.0 for windows, SPSS Inc., Chicago, IL, USA) Comparisons between age groups were done by KruskalWallis test with a subsequent Wilcoxon test. In testicular and corpus and cauda epididymal tissue collected from older stallions, the relative gene expression of aromatase in testicular parenchyma was significantly higher (p<0.05) than in animals of all other age groups. No differences in LHR and FSHR mRNA expression in testes were seen with respect to age. However, quantitative total expression of FSHR-mRNA in corpus and cauda epididymidis was significantly elevated (p<0.05) in older horses compared

The effects of three‐month oral supplementation with a nutraceutical and exercise on the locomotor pattern of aged horses

Multiple in vitro studies assessing articular tissues have indicated that glucosamine and chondroitin sulphate may possess anti-inflammatory effects, but little is known of their clinical effects in vivo. Many old horses have stiff joints, which is likely to be attributable to inflammation and therapy with these nutraceutical compounds could improve joint function. To assess the clinical effects of a mixed supplement on the improvement of stiff gait in aged horses. Randomised, blinded, placebo-controlled study. A group of 24 geriatric equids (age 29 ± 4 years; mean ± s.d.) received either 3 months oral supplementation with a test compound (containing glucosamine, chondroitin sulfate and methyl sulfonyl methane), or a placebo. Kinematic outcome criteria (primary: stride length; secondary: carpal flexion, fore fetlock extension and tarsal range of motion) were objectively quantified on a treadmill at a walk and trot before and after treatment. Stride length did not change significantly in the treated horses at the end of the trial. In the control group, carpal flexion and fore fetlock extension were significantly increased (P<0.05). There were no indications of effect of the supplement on gait characteristics. The observations in the control group may have been due to a habituation or exercise effect. This study does not support the use of a glucosamine/chondroitin sulfate/methyl sulfonyl methane supplement to improve stiff gait in geriatric horses because of the lack of a sizeable effect. The significant changes in gait parameters in the control group may indicate the usefulness of exercise regimens in older horses.

The Athletic Performance of Thoroughbred Racehorses out of Mares with Suspected Placentitis during Gestation

Thoroughbred mares treated for signs of placentitis are potentially costly to farms and owners. Although these treatments often are effective, the resulting foal may require expensive aftercare. The current study investigated the future racing performance of foals from mares treated for clinical and subclinical signs of placentitis compared with matched control mares that had no signs of placentitis producing foals on the same farms. In total, 190 horses born from mares with suspected placentitis met the criteria for analysis and were matched with 190 horses born on the same farm. Mare data and percentage of stakes winners in each group were analyzed with Student t test. Analysis between pairs of horses was done using a paired t test for number of starts, wins, places, shows, and amount earned. Significance was set at a P value of <.05. Mares with suspected placentitis were slightly older than control mares, had slightly shorter lengths of gestation, and had a longer interval to subsequent pregnancy than control mares (P < .05). Horses out of suspected placentitis mares that were racing as 2 year olds in the study had no difference in starts, wins, places, shows, and percentages of black-type race winners; however, this group earned more than their matched control pairs (P < .05). Older horses (3 year olds) out of suspected placentitis mares had no differences in number of starts, wins, places, shows or amount earned; however, the matched control older horses had more black-type race winners (P < .05). The information from this study may aid owners when making decisions about treatment options.

Equine glaucoma: a histopathologic retrospective study (1999–2012)

To characterize and describe the histopathologic findings in equine globes enucleated due to glaucoma. Medical records at The Ohio State University from 1999 to 2012 were reviewed retrospectively. Signalment, history, and treatment data were collected, and histologic slides of enucleated globes were examined and lesions recorded. Twenty-three eyes from 23 horses were eligible for inclusion in this study. The majority of affected horses were > 15 years of age (65%). The ages ranged from 5 to 35 years (mean = 17.4 years). The left eye was affected in 10 cases (43%) and the right eye in 13 cases (57%). There were 13 mares (56%) and 10 geldings (44%). Quarter Horses (30%), Appaloosas (26%), and Thoroughbreds (22%) were the most common breeds in the study population. The most common histopathologic changes included hypercellularity of the optic nerve (93%), retinal atrophy (89%), corneal vascularization (83%), descemetization of pectinate ligaments (83%), hypercellularity of the anterior corneal stroma (75%), posterior bowing of the iris base (74%), ciliary body atrophy (74%), corneal striae (70%), pars plana elongation (60%), cataract (53%), and collapsed ciliary cleft/trabecular meshwork (52%). Evidence of uveitis (cataract, lymphoplasmacytic infiltration of the uvea, and/or anterior or posterior synechiae) was present in 20/23 eyes (87%). Equine glaucoma most commonly occurs secondary to uveitis with Appaloosas and older horses predisposed. Histologic changes are comparable to prior reports of chronic glaucoma; notable findings not previously described in the horse were posterior bowing of the iris base and relative sparing of the superior retina from atrophy associated with elevated IOP.

Radiographic configuration and healing of 121 fractures of the proximal phalanx in 120Thoroughbred racehorses (2007–2011)

Although fractures of the proximal phalanx are one of the most common long bone fractures of Thoroughbred horses in training, limited details on variations in morphology and radiological progression have been published. To describe in detail the configuration of parasagittal fractures of the proximal phalanx in a group of Thoroughbred racehorses, to report fracture distribution within this group of horses and to document radiological progression of fracture healing in cases treated by internal fixation. Restrospective case series. Case records and radiographs of Thoroughbred racehorses with parasagittal fractures of the proximal phalanx admitted to Newmarket Equine Hospital between 2007 and 2011 were analysed. One hundred and twenty-one fractures were identified in 120 Thoroughbred racehorses. Fractures were frequently more complex than was appreciated immediately following injury; a feature that has not been reported previously. There was seasonality of fractures in 2- and 3-year-old horses, but not in older horses. Fractures of the proximal phalanx may be more complex than recognised previously, although often their complexity cannot be identified radiographically immediately following injury. The seasonality observed in 2- and 3-year-old horses is most likely to be a consequence of the timing of the turf-racing season in the UK. The Summary is available in Chinese - see Supporting information.

Comparison of krill oil and fish oil supplementation on serum and tissue fatty acid profiles in horses

s / Journal of Equine Veterinary Science 33 (2013) 321-399 342 0700, 0800, 0900, 1100, 1300, and 1500 hours. Psyllium supplementation lowered glucose (P<0.0001) concentrations, glucose AUC (P<0.0001), insulin AUC (P 1⁄40.0067), and increased time to peak glucose (P 1⁄40.0478).There was a treatment by sex interaction for insulin (P 1⁄40.0101), and peak insulin (P 1⁄40.0163) concentrations, glucose AUC (P 1⁄40.0253), and insulin AUC (P 1⁄40.0129). These variables were lowered to a greater extent in geldings than in mares. Higher NSC intake resulted in higher peak insulin (P 1⁄40.0398) in all horses. Older horses had higher peak insulin (P 0.0091), decreased time to peak glucose (P<0.0001) and decreased time to peak insulin (P 0.0005All characteristics of glucose and insulin decreased (P 0.0154) over the 30 day interval spent grazing pasture. These results indicate that supplementing psyllium in horses grazing cool season grasses lowered systemic glucose and insulin concentrations and these effects may reduce the risk of metabolic diseases, such as laminitis, in horses consuming NSCs. However, systemic glucose and insulin concentrations were effected to a greater extent in males