Welcome to topic 4 for 624EHS - Contemporary Issues in Equine Science.
This topic is all about Equine Obesity. Make sure that you look at the launch powerpoint, which has been posted in the Classroom. All distance learning students are required to contribute to this blog. You have from now until 2 pm on Wednesday 12th of February 2020 to contribute to this blog, to debate the issues surrounding Equine Obesity. Ensure you can also evidence your opinions and remember that you are also required to submit a reference list (word document emailed to module leader) by 2 pm on Wednesday 12th of February. You will be graded on the quality and quantity of both your blog contributions and your reference list. Remember, the point of this is to debate the issues, so you should be replying to each other's posts. I will be keeping an eye on the blog, but if you have any issues, you should email me. Please note that this topic 4, will be marked and will count towards your final coursework 3 mark. Please remember to register your name with your comments so that I know who has contributed with which comment.
What is obesity in the equine world? Overweight and/or obesity in horses is widely regarded by researchers as those having a Body Condition Score of 7/9 or greater, using the Henneke et al., 1983 scale which is more suited to identifying adipose deposits. This indicates that more than 20% of an equid's bodyweight is from fat (Rendle et al., 2018).
ReplyDeleteSo the prevalence of obesity in equine populations is considerably high - ca. 72% (Menzies-Gow et al., 2017; Sánchez-Guerrero et al., 2019). This is particularly the case in native breeds (Brown et al., 2017; Sánchez-Guerrero et al., 2019), which indicates a certain genetic heritability in these breeds (Sánchez-Guerrero et al., 2019). This is acerbated by the type of use these breeds are put to. This includes leisure riding, companion animal either field or human, retirement, and showing competitions (Brown et al., 2017; Morrison et al., 2017). Further to this is the horse-owners' inability or unwillingness to identify obesity in their own animals (Rowland et al., 2019). This compares with the lack of obesity in competition horses, which would support the possibility that leisure horses are being overfed, and thus entering a negative energy balance (Rendle et al., 2018).
What are the impacts of obesity on horses? The initial impact is on the general health of the horse, causing impaired athletic and reproductive performance, thermal stress, excessive loading of joints and hoof, and susceptibility to colic due to variation in the gut microbiome (Rendle et al., 2018; Coleman et al., 2019). Other problems occur at a metabolic level, with the dysregulation of insulin leading to Equine Metabolic Syndrome (EMS) which is one route to laminitis (Bamford, 2016; Menzies-Gow et al., 2017; Fitzgerald, 2019; Ragno et al., 2019), other problems include Cresty Neck Syndrome (CNS), Pituitary par intermedia dysfunction (PPID) and systemic inflammatory response syndrome (SIRS), which are linked to the immune response to excessive adipose deposits (Girardi et al., 2019; Reynolds et al., 2019; Rowland et al., 2019).
These health risks mean that obesity is a serious welfare issue regarding the five freedoms (OIE, 2020), other than having a major impact on the equine industry, due to the cost of treating, implementing specific managing regimes and loss of performance in horses suffering from being overweight (El-Maaty et al., 2017; Morrison et al., 2017; Cipriano-Salazar et al., 2019).
So what can be done about this situation? The first point is to sensibilise the leisure horse-owner population of the risks of obesity, and to teach them how to apply the BCS system objectively to their own horses (Rowland et al., 2019; Jaqueth et al., 2019). This should be supported by greater instruction into the correct feeding of leisure horses, as owner perception of energy consumption by the horse when used for leisure purposes - as a lot of owners seem to imprint their fatigue to that of the horse (Gill et al., 2017; Morrison et al., 2017; Moore et al., 2019; Snalune et al., 2019).
Further research is also needed in understanding the consequences of excessive adipose tissue at a cellular and metabolic level, so as to better determine the outcomes of obesity and thus prevent or reverse their effects (Girardi et al., 2019; Moore et al., 2019; Müller & Lindberg, 2020)
It has been argued that equine obesity is currently the number one equine welfare issue within the UK (Jones, 2020; Vet Times, 2020). Although, this is by no means an issue unique to Britain, as demonstrated in the Kosolofski et al. (2017) study which found 28.6% of the Saskatoon, CA horse population to be overweight or obese. A study conducted in Sweden indicated that emaciation is a more prevalent issue (10.93%) than obesity (0.80%) (Hitchens et al, 2015). However, it should be noted that observation methods during this study may not be standardised, therefore further investigation is required.
ReplyDeleteDuffell (2019) reports that approximately half of the horses in Britain are overweight, although, in concurrence with Simon’s findings, the obesity rate can reach 70% in some populations of native breeds (Rendle et al. 2018). While these findings may well be demonstrative of genetic heritability, owner attitudes towards keeping these breeds should be noted. As mentioned by Simon, native breeds are often kept for leisure use or as companions. Over-rugging, over-feeding, and under-working of these breeds, particularly during the winter months, does not give leave to the natural phenomenon which sees horses leave winter slighter lean due to scarce food and difficult conditions, to allow for a legitimate and healthy gain of weight during the spring months (Jones, 2017; Jones, 2018)
In order to tackle perceptions of weight, incentives to encourage equestrians to keep their horses at a suitable weight have been welcomed. These include awards presented for the “healthiest weight” within a showing class, as judged by a veterinarian, in an attempt to challenge the concept of “show condition” equalling obesity (Jones, 2019).
Access to specialist weight management clinics, including those offered by veterinary practices such as Rossdales and Western Counties, is another opportunity for amateur equestrians to receive accurate reports and advice on topics such as feeding according to workload and condition (Rossdales, 2019; Western Counties, n.d). However, it should be noted here that access to clinics such as these is dependent on client participation. It is not always feasible for individuals to have the means to attend events, especially with their equines, therefore a more remote method of delivery of the importance of weight management should be considered. Vet times (2020) report that following the success of a 6-month pilot, in the summer of 2020, a “traffic light” scheme will be rolled out across the UK. The scheme is designed to revolve around routine vaccination visits, and include the veterinarian placing a sticker on the horse’s passport indicating not only when the next vaccination is due, but what the horse’s body condition score is based on green being healthy, amber being overweight and red indicating morbid obesity. Again, the overall success of these systems is based on client participation, and as a significant proportion of equids within the UK are unvaccinated, they will, therefore, be excluded.
Extending the point on breeds and showing horses made by Robyn, is the increase in the numbers of horses > 20 years old, with a survey in Sweden indicating that obesity was also a problem in this group of horses, again owner perceptions of BCS are underestimated, along with the idea that older horses naturally lose condition - which is not necessarily the case as fat may be present, but the horse due to reduced exercise, has lost muscle condition instead (Müller & Lindberg, 2020).
ReplyDeleteTo help deal with the issue of client participation, then a more direct approach could be used, with yard visits and the involvement of yard owners/managers to help sensibilise horse-owners of the risks of obesity and accurate BCS scoring (Rowlands et al., 2019), also the inclusion of farriers in this discussion would help reach a greater number of owners, even if not shod, hoof trimming is often still required, and combined with the dangers of laminitis and the farrier's role in dealing with disease could be effective (Lynden et al., 2018).
I agree with Simon’s suggestion regarding farriers playing a more active role in educating and sensitising horse owners to issues surrounding equine obesity. My concern would be that there is a portion of owners who either trim their horse’s feet themselves or utilise the services of “barefoot trimmers”. While there has been extensive debate over the issue of barefoot trimming over the past decade, the Farrier’s Registry Council stipulates that barefoot trimming (without the intention of fitting shoes) does not fall under the definition of farriery (FRC, nd). Therefore there are still unlicensed trimmers who operate without formal training, who may not be up to speed with relevant information.
ReplyDeleteFollowing my previous comment regarding the traffic light scheme, it has been reported that the scheme will incorporate the use of QR codes to direct the owner/caregiver to information and videos on weight management (Jones, 2020). While this aspect also relies on client participation and their technical ability to use the service, it could potentially alleviate concerns regarding the standardization of ideals and reduce conflicting weight management advice.
Equine Obesity is the most common health factor affecting the welfare of horses in the UK (Morrison et al, 2017). Obesity prevalence in the UK can reach up to 45%. Obesity effects horses worldwide however prevalence is high in the UK compared to the rest of the world. In comparison to other countries 45% is relatively high prevalence. In Iceland, 10% of the equine population is obese, 24.5% of Australian horses are obese, 29% of the equine population in Canada are obese (Durham et al, 2019). Factors which affect the high prevalence of obesity in the UK should be investigated with aim to reduce obesity.
ReplyDeleteOverweight and obese horses become vulnerable to obesity related illnesses, significantly reducing their quality of life. Obesity can lead to equine metabolic syndrome, laminitis, increased heart rates, increased blood pressure, adipose manifestations, hyperglycemia and hypoadiponectinemia (Durham et al, 2019). Obese horses increase the likelihood of suspensory ligament injuries and early onset of degenerative joint diseases (Gruyaert et al, 2019). Recovering from the illness could incur large vet fees and will reduce the horse’s ability to perform. A healthy weight will allow the horse to compete and continue their career.
Equine obesity is commonly recognised as a horse with a body condition score (BCS) greater than 7 (Coleman et al, 2019). Body condition scoring horses is qualitative and subjective. Although a standardised scoring technique has been developed inexperienced individuals often score horses differently to an experienced assessor resulting in the horse being placed into the incorrect category which then leads to incorrect feeding and work load regimes. Incorrect feeding and work loads result in malnourished or obese horses (DeLano et al, 2017).
In agreement with Simon and Robyn, and in support of the previous study, there is further evidence to suggest that horse owner perceptions of ideal weight is inadequate. Morrison et al (2019) identified that not only inexperienced equestrians lacked ability to correct BCS, equestrian managers also lacked the ability to score correctly. Equestrian managers interpreted that native type breeds which are used for showing purposes should look a certain way and would BCS the horses lower than the visual appearance of the horse despite the horse being overweight. The lower BCS limits the amount of weight loss initiation and increases the possibility of the horse suffering from obesity related illnesses.
The showing industry in the UK prefers horses to be in ‘showing condition’ allowing horses to carry more weight and compete in an obese condition. The culture of the show ring currently promotes overweight horses (Brown et al, 2017). Robyn identified classes which are trying to reduce the ‘showing condition’ culture. However, one class at an event is unlikely to change the entire showing mind set. More needs to be done discourage the overweight culture of showing and promote healthy horses.
Other factors influencing equine obesity include hereditary genetics. 71.14% of Pura Raza Espanol horses are overweight or obese. BCS had a heritability level of low – medium, suggesting genetics are involved in obesity and selectively breeding lower body condition scoring horses could reduce the overall BCS score of the breed (Sanchez-Guerrero et al, 2019). It could be suggested that a similar study could be used to test heritability levels of obesity in Mountain and Moorland ponies to determine if obesity level in these breeds are a result of genetics or just the showing culture.