Optimised environments for horse health and wellbeing: the use of alternative grazing

Despite the role of the horse having changed from working and sporting toward leisure, types of management have remained similar for the past century, with horses still being kept in small stables and paddocks which were predominantly designed for rest and recuperation after hard work. Many of the UK's major equine welfare challenges, such as stress and obesity, can now be traced towards management that does not fit well with horses' ethological needs. Some UK horse owners are now using creative strategies to manage their horses' welfare in a domestic setting, by structuring their turnout areas in ways that are designed around the horses' three key needs of ‘forage, friends and freedom’. Owners suggest that these management systems can be particularly useful for managing some of the most common equine health and wellbeing challenges, including equine metabolic syndrome, laminitis, stress or behavioural issues and arthritis. A better understanding of these systems could therefore be particularly useful to veterinary professionals who commonly need to assist owners in managing those conditions. This article describes the most frequently used alternative grazing systems, and the common advantages and pitfalls of each.

The Influence of Diet Change and Oral Metformin on Blood Glucose Regulation and the Fecal Microbiota of Healthy Horses

Common treatments for Equine Metabolic Syndrome (EMS) and associated conditions include removal from pasture and adoption of an all-hay diet. Pharmacological treatments for EMS include metformin, a biguanide antihyperglycemic agent also administered to people to help improve glucose tolerance and insulin sensitivity. Both treatments may work, at least partially, through the gut microbiota, yet little is known regarding these effects in the equine host. To determine the influence on the fecal microbiota of this diet change and administration of metformin, six healthy horses were removed from pasture and switched to an all-hay diet, with four of those horses also receiving oral metformin for seven days. Control horses (n = 24) remaining on pasture and receiving no metformin were sampled at the beginning and end of one week. All samples were subjected to 16S rRNA sequencing, and horses undergoing the diet change were subjected to an oral sugar test twice, one week apart. Characteristic changes in the microbiota following diet change included the significant expansion of the phylum Kiritimatiellaeota. As Kiritimatiellaeota are related to Verrucomicrobia, found to expand in the microbiota of mice and humans in response to metformin, this taxon may represent the cognate microbes in equine hosts.

The Usefulness of Mesenchymal Stem Cells beyond the Musculoskeletal System in Horses

The differentiation ability of mesenchymal stem cells (MSCs) initially raised interest for treating musculoskeletal injuries in horses, but MSC paracrine activity has widened their scope for inflammatory and immune-mediated pathologies in both equine and human medicine. Furthermore, the similar etiopathogenesis of some diseases in both species has advanced the concept of “One Medicine, One Health”. This article reviews the current knowledge on the use of MSCs for equine pathologies beyond the locomotor system, highlighting the value of the horse as translational model. Ophthalmologic and reproductive disorders are among the most studied for MSC application. Equine asthma, equine metabolic syndrome, and endotoxemia have been less explored but offer an interesting scenario for human translation. The use of MSCs in wounds also provides a potential model for humans because of the healing particularities in both species. High-burden equine-specific pathologies such as laminitis have been suggested to benefit from MSC-therapy, and MSC application in challenging disorders such as neurologic conditions has been proposed. The available data are preliminary, however, and require further development to translate results into the clinic. Nevertheless, current evidence indicates a significant potential of equine MSCs to enlarge their range of application, with particular interest in pathologies analogous to human conditions.