The use of nutritional supplements in dressage and eventing horses

Fluctuations in equine cutaneous pH and transepidermal water loss with time of day and ambient conditions

Cutaneous pH and transepidermal water loss (TEWL) are commonly utilized measures in dermatological research as they provide information concerning barrier function. The importance of dermal health has become more evident in recent years. Accordingly, the aim of this work was to identify natural fluctuations in the biophysical parameters of healthy equine skin. Cutaneous pH and TEWL was collected on nine mares at 6:00 AM, 12:00 PM, and 6:00 PM daily for five days on the nose, withers, girth area, mid-back, and base of tail. Ambient temperature and humidity were measured at each collection. Statistical analysis was completed using SAS On Demand. Tests included repeated measures, ANOVA, and regression analysis. Mean cutaneous pH significantly differed by day (P = 0.0052) and time (P = 0.0073) but was unaffected by anatomical location (P = 0.2841). Interestingly, cutaneous pH had a significant interaction of day and location (P = 0.0004). Mean TEWL measures significantly differed by day (P < 0.0001), time (P < 0.0001), and anatomical location (P = 0.0231). Interaction of day and time had a significant effect on TEWL (P < 0.0001) and also resulted in a three-way interaction of day, time, and location (P = 0.0167). There were no significant associations of pH with temperature and humidity. All measures of TEWL across all locations were significantly correlated with temperature and humidity (P < 0.0001). Cutaneous pH and TEWL measures are affected by environmental conditions which should be considered in future models and work using dermal characteristics of horses.

Understanding and treating equine behavioural problems

Behaviour-related issues are common in horses. Many 'undesirable behaviours' pose important safety concerns for the human handlers / riders / carers, as well as welfare concerns for the horse. Undesirable behaviours can also devalue a horse, or result in the horse being re-homed, relinquished, or euthanased. Undesirable behaviours occur for a range of reasons. These include physiological causes, poor management, and the use of inappropriate or poorly applied handling and training techniques. The potential contribution of each of these aspects must be considered when attempting to reduce or eliminate undesirable behaviours. Effectively modifying the existing behaviour includes investigation and treatment of potential physiological causes, assessing and adjusting existing handling, husbandry and management, and undertaking behaviour modifying training. Unlike in the treatment of dogs and cats, the use of psychotropic agents is uncommon in equine behaviour medicine but the benefits of using these agents in appropriate cases is gaining recognition. This review discusses potential causes for the development and maintenance of undesirable behaviours in horses and highlights the various considerations involved in determining the most appropriate course for reducing or eliminating these behaviours. There is also a brief discussion about the potential role of psychotropic agents as an additional component of an overall behaviour modification plan to reduce or eliminate undesirable behaviours in horses.

Conditionally immortalised equine skeletal muscle cell lines for in vitro analysis

Background

Thoroughbred racehorse performance is largely influenced by a major quantitative trait locus at the myostatin (MSTN) gene which determines aptitude for certain race distances due to a promoter region insertion mutation influencing functional phenotypes in skeletal muscle. To develop an in vitro system for functional experiments we established three novel equine skeletal muscle cell lines reflecting the variation in phenotype associated with MSTN genotype (CC/II, CT/IN and TT/NN for SNP g.66493737C > T/SINE insertion 227 bp polymorphism). Primary equine skeletal muscle myoblasts, isolated from Thoroughbred horse gluteus medius, were conditionally immortalised and evaluated to determine whether cell phenotype and metabolic function were comparable to functional characteristics previously reported for ex vivo skeletal muscle isolated from Thoroughbred horses with each genotype.

Results

Primary myoblasts conditionally immortalised with the temperature sensitive SV40TtsA58 lentivirus vector successfully proliferated and could revert to their primary cell phenotype and differentiate into multinucleated myotubes. Skeletal muscle fibre type, MSTN gene expression, mitochondrial abundance, and mitochondrial function of the three MSTN genotype cell lines, were consistent with equivalent characterisation of ex vivo skeletal muscle samples with these genotypes. Furthermore, addition of coenzyme Q₁₀ (CoQ₁₀) to the cell lines improved mitochondrial function, an observation consistent with ex vivo skeletal muscle samples with these genotypes following supplementation with CoQ₁₀ in the diet.

Conclusions

The observation that the phenotypic characteristics and metabolic function of the cells lines are equivalent to ex vivo skeletal muscle indicates that this in vitro system will enable efficient and cost-effective analyses of equine skeletal muscle for a range of different applications including understanding metabolic function, testing of nutritional supplements, drug test development and gene doping test development. In the multi-billion-euro international Thoroughbred horse industry research advances in the biological function of skeletal muscle are likely to have considerable impact. Furthermore, this novel genotype-specific system may be adapted and applied to human biomedicine to improve understanding of the effects of myostatin in human physiology and medicine.

Horse owners' knowledge, and opinions on recognising colic in the horse

BACKGROUND

Colic is the most common emergency problem in the horse. An owner's ability to recognise colic and seek assistance is a critical first step in determining case outcome.

OBJECTIVES

The aim of this study was to assess horse owners' knowledge and opinions on recognising colic.

STUDY DESIGN

Cross-sectional study.

METHODS

An online questionnaire was distributed to horse owners with open and closed questions on their knowledge of normal clinical parameters in the horse, confidence and approach to recognising colic (including assessment through case scenarios), and their demographics. Descriptive and chi squared statistical analyses were performed.

RESULTS

There were 1564 participants. Many respondents either did not know or provided incorrect estimates for their horse's normal clinical parameters: only 45% (n = 693/1540) gave correct normal values for heart rate, 45% (n = 694/1541) for respiratory rate and 67% (n = 1028/1534) for rectal temperature. Knowledge of normal values was statistically associated with participants' educational qualifications (P<0.01). Owners said if they suspected their horse had colic they would assess faecal output (76%; n = 1131/1486), gastrointestinal sounds (75%; n = 1113/1486), respiratory rate (65%; n = 967/1486) and heart rate (54%; n = 797/1486). There was a lack of consensus on whether to call a vet for behavioural signs of colic, unless the signs were severe or persistent. The majority of participants (61%) were confident that they could recognise most types of colic. In the case scenarios, 49% were confident deciding that a surgical case had colic, but 9% were confident deciding an impaction case had colic.

MAIN LIMITATIONS

Most respondents were UK based; risk of self-selection bias for owners with previous experience of colic.

CONCLUSIONS

There was marked variation in horse owners' recognition and responses to colic, and significant gaps in knowledge. This highlights the need for the development of accessible educational resources to support owners' decision-making.

Veterinary Pet Supplements and Nutraceuticals

Veterinary pet supplements and nutraceuticals are widely used by dog, cat and horse owners across the United States, generating millions of dollars in revenue for manufacturers. Despite the widespread use of these veterinary products, oversight and regulation remain limited as compared to human dietary supplement regulations. This review describes the current regulation, quality control, safety and efficacy of pet supplements and nutraceuticals targeted towards the dog, cat and horse.

Equine Calming Products: A Short Survey Into Their Use, Effect, and Knowledge Using a Small Sample of Horse Owners in the North of Scotland, UK

Equine calming products (ECPs) are often used by horse owners to alter or mitigate unwanted or dangerous behaviors in various situations. Little scientific research to date examines horse owners' knowledge surrounding these products. The objective of this pilot survey was to determine horse owners' use and perceptions of ECPs. For convenience, a survey was distributed to riding club members, livery yards, and riding instructors in the North of Scotland, UK, to ascertain the following information; the number of horse owners and caretakers who use an ECP, whether the product was considered to be effective, reasons for use and identification of the effective ingredient. Total response rate was 63% (n = 58); correctly completed questionnaires were received. Of the total respondents, 69% (n = 40) confirmed the use of an ECP and 82% would use them again, and 45% reporting regular use. Over half (59%) thought the calming effect was induced by magnesium, 9% thought the calming effect was induced by herbs, valerian, or tryptophan, and 32% did not know what ingredient had a possible calming effect. Of those using or having used an ECP, 40% felt that there was some positive effect, 30% were unsure as to whether there was any difference or not, 25% felt there was no difference, and 5% felt there was a negative effect on horse's behavior. A variety of reasons were given for using an ECP. The results suggest that horse owners are willing to use ECPs without underpinning knowledge of ingredients or scientific evidence of efficacy.

Equine dietary supplements: an insight into their use and perceptions in the Irish equine industry

Background

Nutritional supplements are frequently used by horse owners/caregivers to supplement their horse(s) diets. Some work has been done to identify the types of supplements fed and the reasons for doing so; however, this has been predominantly disciple-specific and with little focus on participants’ perceptions of supplement testing and regulation. The aim of this study was to gain an insight into the use and perceptions of equine dietary supplements in the Irish equestrian industry.

Methods

An online survey was designed to ascertain the following information: demographics, types of supplements fed and reasons for use, factors that influenced respondents’ choice of supplement, where advice was sought and perceptions of testing and regulation of equine supplements

Results

The survey yielded 134 responses, 70% non-professionals and 30% professionals. A greater percentage of professionals included supplements in their horse(s) diets (98%) compared to non-professionals (86%). Almost 70% of professionals fed more than two supplements, whereas 80% of non-professionals reported to feed only one supplement. Joint supplements were most commonly fed by all respondents (22%) followed by calming supplements (13%). The enhancement of performance (35%) and prevention of joint disorders (34%) were the most common reasons reported by respondents for using a supplement. Over 53% of respondents sought advice on choosing a supplement from their feed merchant, followed by their veterinarian (46%). Veterinary recommendation was given as the most influential factor when choosing a supplement by 90% of respondents, followed by cost (69%). Most (93%) respondents thought that feed supplements had to meet legal standards, with each batch analysed for quality (72%) and the supplement tested on horses before being launched on to the market (92%).

Conclusion

This study has identified the main types of supplements used in the Irish equestrian industry along with the reasons for their use. However, it has also highlighted major misperceptions in how supplements are tested before being launched for sale and further work on this aspect of the findings would be beneficial.