Search Results (26)

This study investigated the presence of antibodies to human adenovirus type 36 (HAdV-D36) in horses with different metabolic statuses, including normal, overweight, and those diagnosed with equine metabolic syndrome (EMS). A total of 151 serum samples were tested, of which 47.6% were positive for anti-HAdV-D36 antibodies. Although the horses were confirmed to be susceptible to HAdV-D36 infection, there was no significant correlation between infection and blood glucose or cholesterol levels. However, the triglyceride levels showed significant differences—they were particularly elevated in the seropositive horses with EMS. These findings suggest that the virus may act by a different mechanism in horses than in other species, and highlight the need for further research to understand its role in horses. Full article

Equine asthma is a chronic respiratory disease characterised by neutrophilic inflammation, airway hyperresponsiveness, and impaired pulmonary function. Obesity, increasingly prevalent among domestic horses, has been identified as a potential risk factor for exacerbating inflammatory conditions. This study aimed to explore whether obesity modifies neutrophil metabolism and inflammatory responses in horses affected by asthma. Six asthmatic horses in clinical remission were categorised into two groups: obese and non-obese, based on body condition score. Serum levels of interleukin-1β (IL-1β) and peripheral blood neutrophil counts were significantly higher in obese horses, indicating a heightened systemic inflammatory state. Neutrophils from obese horses displayed a stronger oxidative burst following zymosan stimulation and elevated IL-1β gene expression in response to lipopolysaccharide, suggesting a hyperinflammatory phenotype. Metabolomic profiling of neutrophils identified 139 metabolites, with notable differences in fatty acids, branched-chain amino acids, and tricarboxylic acid (TCA) cycle intermediates. Pathway enrichment analysis revealed significant alterations in fatty acid biosynthesis, amino acid metabolism, and glutathione-related pathways. Elevated levels of itaconate, citraconic acid, and citrate in obese horses indicate profound metabolic reprogramming within neutrophils. These results suggest that obesity promotes a distinct neutrophil phenotype marked by increased metabolic activity and heightened responsiveness to inflammatory stimuli. This altered profile may contribute to the persistence or worsening of airway inflammation in asthmatic horses. The findings underscore the importance of addressing obesity in the clinical management of equine asthma and open avenues for further research into metabolic-targeted therapies in veterinary medicine. Full article

Prevalence of endocrine disease in sport horses has been sparsely reported. They often compete well into their teenage years; thus, diagnosis and control of endocrine disease could be important to maintain performance and optimise health and welfare. The aim was to compare the prevalence of pituitary pars intermedia dysfunction (PPID), insulin dysregulation (ID) and metabolic obesity between sport and non-sport type breeds and assess disease progression. Blood samples submitted for plasma adrenocorticotropic hormone (ACTH), serum insulin or adiponectin were included in this study. Horses were grouped according to their breed into sport horses, which are typically used for athletic purposes, and non-sport horses, which are less-athletic breeds typically used for leisure. Cases included 1365 non-sport horse initial samples with 1850 non-sport horse follow-up samples and 1022 sport horse initial samples with 1081 sport horse follow-up samples. PPID and metabolic obesity were found to be as prevalent in the sport horse population, but non-sport horses were more likely to have ID. Upon follow up examination PPID was more prevalent with higher median ACTH in sport horses. This was also true of metabolic obesity in sport horses at follow-up, although median adiponectin was higher, perhaps indicating that the population is less severely affected than non-sport horses. Screening for endocrinopathies should be considered in sport horses presenting with poor performance. Full article

The gut microbiota plays a basic role in maintaining the psychophysical health and well-being of horses. Understanding the complex interactions among microbial communities in relation to age, management, and health is a topic of growing interest. The equine microbiota, given its complexity, is subject to variations caused by internal or external stressors that can lead to metabolic problems and pathologies, i.e., obesity and laminitis. The aim of this study was to characterize the fecal microbiota of 12 purebred Arabian horses and to compare the microbial communities in two distinct management systems (Group 1 = box 22 h/day + paddock 2 h/day and Group 2 = paddock 24 h). Fecal samples were analyzed using high-throughput sequencing of 16S rRNA V3-V4 amplicons. The microbiota was predominantly composed of Firmicutes (32–53%) and Bacteroidetes (32–47.8%), with Ruminococcaceae emerging as the most prevalent bacterial family (10.9–24%). Comparisons of alpha and beta diversity revealed no statistically significant differences between the groups based on different management systems. This preliminary characterization contributes valuable data for understanding the equine fecal microbiota and lays the groundwork for future studies on the relationship among intestinal microbiota and equine health, performance, and management strategies. Full article

Horses evolved to live in herds, continuously moving and foraging. Domestic horses often have limited social contact and movement, with high calorific intake, contributing to obesity. “Track grazing” is an increasingly popular management system, but evidence of its impact on weight management, behaviour, and welfare is limited. Horses (n = 19) resident at HorseWorld (UK) were observed July to October 2023, monitoring bodyweight (kg), Body Conditions Score (BCS), hoof health, behaviour, and welfare indicators. Horses on track grazing systems lost significantly more bodyweight (kg) (F(1,15) = 8.752, p = 0.010) than their restricted grazing counterparts, although this was not supported by BCS findings which may be ineffective for subtle body weight changes. Horses on track grazing systems lost (mean ± S.D.) 10.67 ± 9.9 kg from their starting weight, whereas those on the traditional paddock systems gained 6.8 ± 13.7 kg. Hoof health and general welfare assessment scores were maintained. More behaviours in “positive”, “negative”, and “neutral” categories were observed in paddock system horses than those on the track grazing system, although these differences were not statistically significant. These findings suggest that horses prone to bodyweight gain can be managed effectively using track grazing systems whilst maintaining health and welfare. Full article

Obesity is an important health concern in horses, along with humans and companion animals. Adipose tissue is an inflammatory organ that alters the insulin-signaling cascade, ultimately causing insulin dysregulation and impaired glucose metabolism. These disruptions can increase the risk of metabolic disease and laminitis in horses and may also impact energy metabolism during exercise. A single bout of exercise, along with chronic exercise conditioning, increases insulin sensitivity and glucose disposal via both contraction- and insulin-mediated glucose uptake pathways. Regular exercise also increases calorie expenditure, which can facilitate weight (as body fat) loss. This paper explores the metabolic pathways affected by adiposity, as well as discusses the impact of exercise on insulin metabolism in horses. Full article

Donkey medicine is gaining attention due to their increased use as companion animals, in shows, asinotherapy, etc. The increasing demand and unique aspects call for specialized care, requiring new information (physiology, infectious disorders, pharmacology, etc.). Since obesity is common in this species, hyperlipemia, metabolic syndrome and insulin dysregulation (ID) are common disorders in donkeys, in some cases with high mortality, either directly (multiorgan dysfunction) or indirectly due to poor quality of life (chronic laminitis). Donkeys have long-life expectancy and are often afflicted with pituitary pars intermedia dysfunction (PPID), a neurodegenerative and endocrine disease. Hyperlipemia is diagnosed based on high plasma triglyceride concentration in association with clinical findings and laboratory abnormalities from affected tissues (liver, kidney and pancreas). The measurement of resting serum insulin and plasma ACTH concentrations is the first step in ID and PPID diagnosis. In donkeys with clinical signs of ID (obesity or recurrent laminitis) or PPID (hypertrichosis, regional adiposity, laminitis and weight loss), where these hormones are in the normal or non-diagnostic range (donkey-specific cut-off values and reference ranges need to be established), dynamic tests are recommended (oral sugar test or thyrotropin-releasing hormone, respectively). Equine treatment protocols apply to donkeys, although pharmacological studies for most drugs, except pergolide, are lacking. Full article

Equine metabolic syndrome (EMS) has become an important issue in modern veterinary medicine and is linked to the common, extremely painful, most-of-the-time performance-terminating hoof laminitis. The growing knowledge in the field of genetic background, inducing environmental factors, diagnosis, treatment and maintenance of affected equines led us to summarise the available information to be used not only for scientific purposes but for fieldwork. In horses, the clinical presentation of EMS includes: obesity or local fat deposition, bilateral lameness or hoof rings attributed to ongoing or previous (pasted) laminitis with the key feature of the occurrence of insulin dysregulation, disturbing the homeostasis within insulin, glucose and lipid metabolism. The management of EMS is based on dietary and fitness discipline; however, intensive research is ongoing in the field of regenerative medicine to develop modern and promising therapies. Full article

There is ample research describing the increased risk of health concerns associated with equine obesity, including insulin dysregulation and laminitis. For athletes, the negative effect of weight carriage is well documented in racing thoroughbreds (i.e., handicapping with weight) and rider weight has been shown to impact the workload of ridden horses and to some degree their gait and movement. In many groups of competitive and athletic horses and ponies, obesity is still relatively common. Therefore, these animals not only are at risk of metabolic disease, but also must perform at a higher workload due to the weight of their adipose tissue. Excess body weight has been documented to affect gait quality, cause heat stress and is expected to hasten the incidence of arthritis development. Meanwhile, many equine event judges appear to favor the look of adiposity in competitive animals. This potentially rewards horses and ponies that are at higher risk of disease and reinforces the owner’s decisions to keep their animals fat. This is a welfare concern for these animals and is of grave concern for the equine industry. Full article

Horses are large non-ruminant herbivores and rely on microbial fermentation for energy, with more than half of their maintenance energy requirement coming from microbial fermentation occurring in their enlarged caecum and colon. To achieve that, the gastro-intestinal tract (GIT) of horses harbors a broad range of various microorganisms, differing in each GIT segment, which are essential for efficient utilization of feed, especially to use nutrients that are not or little degraded by endogenous enzymes. In addition, like in other animal species, the GIT microbiota is in permanent interplay with the host’s cells and is involved in a lot of functions among which inflammation, immune homeostasis, and energy metabolism. As for other animals and humans, the horse gut microbiome is sensitive to diet, especially consumption of starch, fiber, and fat. Age, breeds, stress during competitions, transportation, and exercise may also impact the microbiome. Because of its size and its complexity, the equine GIT microbiota is prone to perturbations caused by external or internal stressors that may result in digestive diseases like gastric ulcer, diarrhea, colic, or colitis, and that are thought to be linked with systemic diseases like laminitis, equine metabolic syndrome or obesity. Thus, in this review we aim at understanding the common core microbiome -in terms of structure and function- in each segment of the GIT, as well as identifying potential microbial biomarkers of health or disease which are crucial to anticipate putative perturbations, optimize global practices and develop adapted nutritional strategies and personalized nutrition. Full article

Laminitic horses commonly suffer from an endocrine disease such as equine metabolic syndrome. Hyperinsulinemia is considered a key factor in the pathogenesis of laminitis. Since insulin also affects protein turnover in the body, the resting plasma amino acid concentrations of obese horses that were presented for a combined glucose insulin test (CGIT) were determined. In total, 25 obese horses and two lean horses with recurrent laminitis underwent a CGIT. Of these, five were not insulin dysregulated (obese), 14 were insulin dysregulated (ID), and eight were insulin-dysregulated and laminitic (IDL). Significant differences in the resting concentrations between obese and insulin dysregulated and laminitic (citrulline p = 0.038, obese: 73.001 ± 12.661 nmol/mL, IDL: 49.194 ± 15.486 nmol/mL; GABA p = 0.02, obese: 28.234 ± 3.885 nmol/mL, IDL: 16.697 ± 1.679 nmol/mL; methionine p = 0.018, obese: 28.691 ± 5.913 nmol/mL, IDL: 20.143 ± 3.09 nmol/mL) as well as between insulin dysregulated individuals with and without laminitis (GABA p < 0.001, ID: 28.169 ± 6.739 nmol/mL) regarding three amino acids were determined. This may be an interesting approach, especially for diagnostic testing and possibly also for the feed supplements of horses at risk of developing laminitis. However, further research, including a higher number of cases, is required. Full article

Obesity is a common feature in horses suffering from metabolic syndrome. While adipokines involvement as biomarkers is better established in human pathology, little data are available on horses. This study aimed to investigate the possible association and relationship between selected metabolic parameters and morphological traits in equine metabolic syndrome. Adiposity was evaluated using body condition score (BCS) and cresty neck score (CNS). Plasma levels of total cholesterol, insulin, NEFA, and adipokines (omentin and chemerin) were determined using enzyme-linked immunosorbent assays. Spearman correlation, univariate linear regression analysis and hierarchical clustering were performed. Significant positive correlations were observed between NEFA and bodyweight (r = 0.322; p = 0.006), BCS (r = 0.295; p = 0.013), and CNS (r = 0.267; p = 0.024), total cholesterol and bodyweight (r = 0.262; p = 0.027), and omentin and CNS (r = 0.234; p = 0.049). Cluster analysis supported these results and provided more details on the relationships between studied variables within and between the four resulting groups. These findings highlight NEFA, chemerin, and omentin as valuable biomarkers that could be further analyzed in other horse breeds for a better understanding of equine metabolic pathology. Full article

Obesity and overconditioning are becoming more prevalent in horses, and are influencing the animal’s health, activity, and reproductive efficiency. Body condition score (BCS) and cresty neck score (CNS) have been correlated with the development of various diseases. Many of the papers in the literature evaluate the prevalence of obesity and overconditioning in horse populations considering BCS given by owners. The aim of this study was to evaluate the validity of the owners’ estimation of the degree of equine obesity or overconditioning by comparing BCS and CNS provided by each owner and a board-certified vet to a cohort of 259 horses and their agreement based on age, breed, sex, and activity of the animals. Overconditioning was present in 29% and 24% of horses according to the owners and the vet, respectively, and obesity in 2% and 1%, respectively. Agreement between BCS and CNS given by the owners and the vet was slight, with owners scoring horses either lower or higher than the vet. Agreement between the owners and the vet assessment was also influenced by age, breed, sex, and activity of the animals. Education of owners and caretakers to correctly assess BCS and CNS and regular evaluation of the animals throughout the year is important to prevent the development of obesity and overconditioning and related diseases. Full article

As obesity is a serious problem in the human population, overloading of the horse’s thoracolumbar region often affects sport and school horses. The advances in using infrared thermography (IRT) to assess the horse’s back overload will shortly integrate the IRT-based rider-horse fit into everyday equine practice. This study aimed to evaluate the applicability of entropy measures to select the most informative measures and color components, and the accuracy of rider:horse bodyweight ratio detection. Twelve horses were ridden by each of the six riders assigned to the light, moderate, and heavy groups. Thermal images were taken pre- and post-exercise. For each thermal image, two-dimensional sample (SampEn), fuzzy (FuzzEn), permutation (PermEn), dispersion (DispEn), and distribution (DistEn) entropies were measured in the withers and the thoracic spine areas. Among 40 returned measures, 30 entropy measures were exercise-dependent, whereas 8 entropy measures were bodyweight ratio-dependent. Moreover, three entropy measures demonstrated similarities to entropy-related gray level co-occurrence matrix (GLCM) texture features, confirming the higher irregularity and complexity of thermal image texture when horses worked under heavy riders. An application of DispEn to red color components enables identification of the light and heavy rider groups with higher accuracy than the previously used entropy-related GLCM texture features. Full article

Obesity is a common problem in horses. The associations between obesity and equine metabolic syndrome (EMS) and between EMS and laminitis are known. However, there is a lack of data on whether obesity itself can affect hoof lamellae. Forelimbs and blood from 12 draft horses (six obese and six lean) from a slaughterhouse were acquired. To exclude laminitis and EMS horses, insulin concentration was measured, and hooves were radiographed. Histological evaluation was performed. The shape of the primary and secondary epidermal lamellae (PEL and SEL) was evaluated, and the length of the keratinized and total primary epidermal lamellae was measured (KPEL and TEL). All horses showed pathological changes in lamellae. In the lean group, the changes were longer SELs, more proliferated and separated PDLs, and less standard PDLs. In the obese group, the changes were a lower number of club-shaped and standard SELs and significantly more tapered SELs. No difference in the shape of PELs and the length of KPELs was noticed. The research did not confirm the effects of obesity on lamellar failure. The measurements taken indicate that the lamellae are much longer compared to other research studies; this could indicate that the length of the PEL depends on the hoof size. Full article