Open research questions in Veterinary Equine Medical Research

Summary An 11‐day‐old warmblood colt was referred to the Large Animal Teaching Hospital, University of Copenhagen, for further investigation of a stiff neck and lateral deviation of the poll, with suspicion of a congenital cervical vertebral abnormality.

In equines, the relationship between palpation-based MPS indicators, gait asymmetries, and pain-related behaviours during ridden work remains unclear.

One of the primary limitations of instrumental case studies is their limited generalisability. Since these studies often focus on a case or a small number of cases chosen for their relevance to a specific research question, it can be challenging to generalise the findings to a broader population or context. The results may not be representative of other cases or situations. The current study has focused on a small group of mental health practitioners who are using equine- based therapy, making it difficult to generalise the findings. Moreover, the researcher had Social Work/Maatskaplike Werk, 2026: 62(1) 178 difficulty in accessing mental health practitioners who use equine-based therapy as there are only a few in the field.

While our study revealed small relations between coping behaviour and inhibitory control, it needs to be noted that several limitations need to be considered. First, we might not have completely captured inhibitory control in horses. While we selected three inhibitory control tests that have previously been established with horses and are thought to measure different aspects of inhibitory control, it is possible that we have missed aspects of inhibitory control in horses. A larger test battery with additional inhibitory control tests and a validation for temporal stability would be necessary to overcome this issue. Although, given the inherently flexible nature of IC, which requires a certain sensitivity to environmental stimuli for updating novel task contingencies, it may be difficult to demonstrate temporal stability of IC measures. Alternatively, it is possible that the two coping contexts (delayed turnout and delayed feeding) did not capture behaviours related to inhibitory control, but rather only how much the horses valued food or contact with conspecifics, rather than less context-specific coping behaviour. We selected those two contexts because they mimic situations that a horse could encounter on a daily basis; however, for example, we did not test the horses in situations, in which they would have more control over their exposure to the stressors, and thus more behavioural options to respond, such as novel situations (e.g. novel object/human test) or during interactions with humans (e.g. trainability) and conspecifics (i.e. dominance). Secondly, our sample population was rather standardised as we deliberately decided to reduce the variation of external influences for this first study on the relationship between coping and inhibitory control in horses. All horses were kept in suboptimal housing conditions (i.e. in individual stables with limited turnout), which have been linked to reduced welfare35. Consequently, it is possible that coping mechanisms had already been activated in response to the housing conditions and this was masking the relationship between coping and inhibitory control. In addition, the horses may have already learned that exhibiting certain behaviours would lead to faster success and, consequently, we did not capture their normal coping behaviour. For example, excessive kicking at the walls would prompt stable staff to feed these horses first or rearing and neighing would lead to them being turned out first. While we did not observe any changes in husbandry routine regardless of the horses’ behaviour, this could still have happened unconsciously. Testing more diverse horse populations in terms of sex, genetic background, training, and housing conditions may yield more nuanced results. For future studies, it will be particularly interesting to investigate whether horses exhibiting high levels of stereotypical behaviours or horses that exhibit other signs of welfare impairment (e.g. apathy or aggression) show altered inhibitory control and whether this is modulated by the severity of the abnormal behaviours. Two horses in our sample exhibited intense crib-biting behaviour, which has been linked to dopamine dysfunction88 and altered impulse control and/or differently perceived reward values89,90,but see44. While these two horses did not show consistent differences in their scores derived from the inhibition tests compared to the other horses (except for both scoring very high on the Indecisiveness component), it is unclear whether they might have biased the results. Ultimately, it might be worthwhile to expand this line of research also to other farm animal species that often show abnormal behaviours due to suboptimal housing standards, such as pigs and chickens. Considering that inhibitory control can be enhanced by training91 and appears to have a strong genetic component92, new avenues for improving animal welfare may be particularly promising.

Saddle pressure measurement systems are mentioned as tools to evaluate pressure distribution patterns during ridden exercise in association with lameness and altered spinal range of motion, but no specific testing protocol is proposed to integrate saddle pressure dynamics into the PSF framework validation across PSF− and PSF+ states.

The paper identifies that biomechanical parameters show between-measurement variability and range-of-motion parameters may exceed differences between symptomatic and asymptomatic horses, yet does not specify the required sample sizes, measurement frequency intervals, or standardized environmental/surface conditions needed for robust PSF state discrimination in longitudinal studies.

Research Question 6 requires longitudinal motion analysis tracking inter-day variability in stride length, step length, and phase timing to test whether PSF+ horses demonstrate significantly lower variance than PSF− horses, and critically, whether these variability metrics can prospectively predict future lameness development.

Research Question 5 requires standardized longitudinal infrared thermography (IRT) protocols with quantification of interlimb thermal asymmetries and regional hotspots in lumbosacral and distal limb regions to establish whether thermal normalization can serve as a physiological correlate of functional reorganization from PSF− to PSF+ states.

Research Question 4 requires standardized speed-controlled assessments using force plates or body-mounted inertial sensors (IMUs) to quantify stance-to-suspension phase ratios and test the hypothesis that PSF− horses exhibit increased suspension phase compared to PSF+ horses under comparable conditions.

Research Question 3 needs high-resolution force plate measurements to detect measurable differences in limb symmetry between left and right forelimbs and hindlimbs in vertical GRF, including differences in peak magnitude, peak timing, and temporal distribution across stance phase between PSF− and PSF+ states.

Research Question 2 requires high-resolution force plate measurements synchronized with kinematic capture to assess vertical GRF curve morphology, peak timing, and tangential relative motion during stance phase in trot, specifically comparing single-peaked curves in PSF+ to double-peaked or temporally shifted curves in PSF− states.

Research Question 1 requires validation of kinematic parameters of tubera coxarum motion between PSF− and PSF+ states using motion capture systems or IMUs, with specific need for skin-mounted markers placed over L6 and S1 spinous processes to quantify dynamic interspinous distance changes during locomotion.

Generally large, poorly defined and bulging, due to their involvement in regulating the flow of CSF, ependymomas can cause dilation of the ventricle and, in humans, are recognised to metastasise to the ventricular system and meninges through the CSF.

Summary Background Limited data exist on the benefits of using standing cone‐beam computed tomography (CBCT) contrast tenography before tenoscopy of the digital flexor tendon sheath (DFTS).

Horses with different SNP genotypes (rs1150531051T>C) differed in their speed and distance qualities, which indicates the need for further study of the associations of ACTN3 variants with performance.

Summary Background Brain natriuretic peptide (BNP) serves as a crucial cardiac biomarker in human and small animal veterinary medicine, yet its role in equine cardiology remains underexplored.

While aetiology and pathogenesis of ES have not yet been fully determined, a chronic exaggerated immune response to one specific or multiple antigens is frequently hypothesised.

The shedding of EG components such as syndecan-1, heparin sulfate (HS), and hyaluronan shedding both intravascularly and peritoneally in horses has not been evaluated.

Fast localised abdominal ultrasonography of horses (FLASH) is frequently used as a diagnostic tool in the investigation of colic at referral hospitals, but its use in first opinion practice has not been evaluated.

Self‐inflating tissue expanders (STE) have not been widely adopted by veterinary surgeons, and clinical descriptions of their use in horses are lacking.

Summary A 13‐year‐old gelding was referred to the University of Liverpool Equine Hospital for further investigation of ataxia and neck pain following a suspected traumatic incident in the field 5 days prior.

The outcome following reduction of IIH utilising a noninvasive manual reduction (MR) technique in a large number of horses has not been previously reported.

Summary Chronic inflammatory bowel diseases (IBDs) are a group of gastrointestinal (GI) disorders described in both humans and animals, but unlike in other species, in horses they are poorly defined and there is a lack of standardisation of the method of diagnosis.

There has been a myriad of treatments and topical preparations proposed for treating WLD, but most remain controversial with few having any scientific documentation or evidence of efficacy.

This review of WLD is based on the sparse information available in the veterinary literature, the large number of WLD cases treated successfully in the authors’ combined practices using conventional farriery and the relevant questions that hopefully can be answered in the future.