Commercial equine production in New Zealand 4: welfare implications of the New Zealand production systems

The horse as a pest

The Kaimanawa horses, which are a small feral population of horses in the central plateau region of the North Island of New Zealand, provide a good example of this conflict in perception of worth. The Department of Conservation regard the feral horse population as pests, because over-grazing places unnecessary pressure on a delicate subalpine ecosystem (Rogers 1991). To alleviate pressure on the ecosystem, selective musters and culls of the population have been conducted biannually, or at a frequency that allows the herd numbers to be maintained at ~300 (Department of Conservation 2012). These musters address a secondary aim of the Department of Conservation to improve the welfare state of the remaining horses. Without natural predators, the herd would continue to grow, resulting in over-population and increased pressure on grazing resources, leading to reduced welfare of all the horses (Linklater et al. 2000; Cameron et al. 2001).

Horses were initially culled as part of the muster; however, for a sector of society, these feral horses are regarded as a ‘national treasure’ that must be maintained (Jones 2011; Scasta et al. 2020). There are now rehoming programs, run by charities, for suitable candidates after the musters. The unique aspect of the management of the feral Kaimanawa horses is the cooperation of the federal government (Department of Conservation and New Zealand Army) and advocacy groups (Kaimanawa Heritage Horses and Kaimanawa Wild Horse Protection Society) in the management strategy of the feral horse herd and the local environment (Scasta et al. 2020). Previously, all horses unable to be rehomed after the muster were sent to slaughter; however, in recent musters there has been sufficient demand for horses to alleviate the need for the processing of unwanted horses, due in part, to campaigning and fundraising of Kaimanawa horse training and competition events.

Although considered a pest species, the Kaimanawa horses are protected under the Animal Welfare Act (New Zealand Government 2022) both in their feral state and after the muster. However, different sections of the Act, with differing welfare standards, pertain to the horses in their feral or domestic (post-mustered) state. Furthermore, Kaimanawa and other feral horses are covered only by the Code of Welfare for Horses and Donkeys (New Zealand Government 2018) after the muster, once they are under human care. The Code of Welfare for Horses and Donkeys expands on the obligations in the Animal Welfare Act and includes both minimum standards and recommended best practices for equine welfare.

The horse as a production animal and pet

In New Zealand, racehorses, but also in some instances sport horses, fall into the category of production animals. The marginal utility of production animals is typically related to the return on the investment provided by these horses. Many leisure and sport horses tend to be classified somewhere in between a production animal and a companion animal. Horses regarded as companion animals (pets) tend to have a disproportionately high marginal utility, linked to the high emotive value owners place on their pets and not related to their true economic value.

Economic worth versus marginal utility of the horse

The position of the horse on the scale of marginal utility (Fig. 1) is nevertheless transient. Data from Ireland demonstrated a clear association between the success of the national economy and horse production (Fig. 2a, b). During 2005–2008, while the economy was buoyant (Celtic Tiger), the number of Thoroughbred and sport-horse foals born in Ireland remained constant. In contrast, after the global financial crisis, and as the national debt increased from 2008 (Fig. 2b), there was a dramatic increase in the number of horses sent to the abattoir, and a rapid decrease in the number of foals born (Leadon et al. 2012). These results suggest that the marginal utility of the same type of horses shifted as a result of the changes in the economic climate.

Fig. 2.

(a) A representation of the number of Thoroughbred and Sport-horse foal births between 2005 and 2010 in Ireland. (b) A representation of the total horse numbers slaughtered and total central government debt percentage of gross domestic product in Ireland (as presented by Leadon et al. 2012).

In the current global climate of constant worldwide media and social media access with graphic images, welfare concerns, particularly in the racing or production sectors, may be temporally influenced by a sector of society with little to no equine knowledge (Legg et al. 2019). The views of this previously naïve sector of society may be in stark contrast to participants within the equine industry, but targeted media coverage can greatly influence the perceived worth of the horse and thus acceptable welfare standards. These changing pressures influence governing bodies to alter the welfare and perceived worth of the horse through the industry’s social licence to operate (Heleski et al. 2020).

Public perception of racehorse welfare

The public concern for welfare of racehorses appears to be largely focused on Thoroughbred racing itself, and concerns directly related to racing, rather than issues relating to the growth and development of the racehorse. The focus from lobby groups and issues highlighted in public press and social media have tended to focus on emotive statements about immature horses, whipped to perform, catastrophic injuries, the number of horses sent to slaughter post-racing and the risk to horses from falling in jumps races (Legg et al. 2019; Heleski et al. 2020). However, discussion around racing in New Zealand media appears minimal and short-lived, typically sparked by an adverse event that is publicised, indicating that racehorse welfare is not a high priority for mainstream New Zealand public (Legg et al. 2019). Public concern tends to focus on Thoroughbred racing more than Standardbred racing, possibly due to a lower public profile and lower incidence of fatalities in Standardbred racing (Gibson et al. 2022b).

Two-year-old racing

The optimisation of the equine musculoskeletal system and impact of 2-year-old racing on horse welfare and health has been discussed in detail in a number of reviews (Rogers and Dittmer 2019; Rogers et al. 2020). In contrast to the proclamations from the lobby groups, and what appears to be a perception that has permeated even the non-racing equestrian press, there is a positive association of 2-year-old training and racing, with proxy measures of musculoskeletal health such as career length, number of race starts and prize money earned (Tanner et al. 2011, 2013; Flash et al. 2022). This association appears dose dependent, with the positive association increasing with the level of activity (racing vs just being in training) as a 2-year-old. This association makes physiological sense as the application of training load is provided when the musculoskeletal system is at its most responsive. The positive associations between early age of entry to training and competition on career length have also been observed in show jumping, dressage and event horses (Rogers et al. 2012a).

Whip use

The use of the whip in Thoroughbred racing has proven a contentious issue (Marshall 2008; Smith 2009). The jockey is faced with a balancing act; if the whip is not used and the horse fails to win or place, then they may be charged with failing to ride a horse to its merits, while too much use of the whip, or inappropriate use of the whip, results in a welfare issue and disciplinary action from the racings regulatory body (New Zealand Thoroughbred Racing 2021).

In response to animal-welfare concerns, and as a pragmatic approach, the padded whip has been implemented in Thoroughbred racing in a number of countries. On 1 August 2009, padded whips became mandatory in New Zealand, bringing the country on par with nations such as Australia, India, Ireland and United Kingdom. However, robust research into the effectiveness and the welfare implications of these whips is lacking. In 2011, The British Horseracing Authority (BHA) conducted a review of the whip use in horseracing (BHA 2011). An analysis by Jones et al. (2015) criticised the report’s conclusion that whip use in racing is not a welfare problem, that it does not cause pain and that whip use is necessary for encouragement and safety. The primary driver for the poor critique of the BHA report on whip use was the consistent lack of adequate scientific evidence to support these claims (Jones et al. 2015). However, both the report by BHA and Jones et al. (2015) identified that there were no studies that had objectively and directly assessed horse welfare in relation to whip use in races.

In addition to restrictions on type of whip used, the guidelines of Thoroughbred racing in New Zealand further state that riders cannot strike a horse forward of its shoulder, carry more than one whip and should never ‘strike a horse with a whip in a manner or to an extent which is: (i) unnecessary (ii) or excessive (iii) or improper’ (rule 638, pp. 94–95) (New Zealand Thoroughbred Racing 2021). The wording in regard to the manner of which a horse can be struck is somewhat more subjective and open to interpretation than in the equivalent rules in Australia and the United Kingdom. The racing guidelines in Australia (AR132, pp. 66–67) and the United Kingdom (rule (F)45) are more detailed in terms of whip use and clearly state that appropriate use of the whip is to be considered within the context of the horse’s ability to respond and improve/maintain its position within the race (New Zealand Thoroughbred Racing 2021; Racing Australia 2022). Current revision of the whip-use rules in the United Kingdom requires the whip to be used in the only backhand (as opposed to the forehand) position, effectively limiting the force with which a jockey is able to strike the horse (rule (F)45) (British Horseracing Authority 2022).

The effectiveness of the whip on velocity during racing is also questionable, with only one study having examined this question. Evans and McGreevy (2011) reported that horses achieved highest velocity when whip use was absent, and whip use was most frequent in fatigued horses (Evans and McGreevy 2011). The need for the use of the whip to maintain racing integrity may also have limited merit, with one study identifying no differences in stewards reports of events between whip-free and whipping-permitted races (Thompson et al. 2020).

Injuries associated with racing

A focal welfare concern of the racing industry is the risk of injury during training and racing. The primary reason for involuntary loss of horses from racing and lost training days is musculoskeletal injury (lameness), followed by respiratory conditions (Perkins et al. 2005; Gibson et al. 2022b). These reasons are not unique to racing and were also reported in other industries such as show jumping, and even within lower-intensity activities such as riding school horses (Lönnell 2012; Lönnell et al. 2012). Most lost training days in racing are associated with 2-year-old horses, and the primary reason for lost training days relates to dorsal metacarpal disease (bucked shins or shin soreness; Perkins et al. 2005). Dorsal metacarpal disease relates to the rapid response of naïve bone to the loads of gallop exercise (Nunamaker et al. 1990; Firth et al. 2005). There are now robust physiological and epidemiological data providing a framework on how the early introduction of only a few high-speed load cycles (gallop strides in Thoroughbreds) early in the racing preparation can reduce the risk of dorsal metacarpal disease (Firth et al. 2005; Verheyen et al. 2005).

For older racehorses, injury prevention focuses on mitigating the risks associated with the accumulation of training load cycles. The tissues most sensitive to this are bone (fracture), tendon (strain and rupture) and cartilage (osteoarthritis) (Rogers et al. 2012b, 2020). The failure of bone relates to the cyclic overload of the tissue and thus it is primarily due to inappropriate timing of load cycles and timing of periods of rest and tissue recovery (Martig et al. 2014; Bogers et al. 2016). In contrast, both cartilage and tendon have very low rates of tissue turnover and the integrity of the tissue reduces with age and number of load cycles. Thus, the challenge for the trainer is how to optimise fitness, while minimising risk of injury (Rogers et al. 2007b, 2012b). Within Australasia, the conceptual approach has been to provide maximal fitness from minimal training load (an efficiency approach) in an attempt to reduce the risk profile to training load (Rogers et al. 2007b; Bolwell et al. 2010; Morrice-West et al. 2020). In contrast, racehorse trainers in the United Kingdom characteristically use large volume of training load to achieve maximal fitness, so as to reduce risk to injury (Verheyen et al. 2006).

The rate of catastrophic injury within Thoroughbred flat racing and Standardbred racing in New Zealand appears low, compared with other racing jurisdictions (Hitchens et al. 2019; Gibson et al. 2022a, 2022b). This is possibly an interaction of the early production process, the pattern of racing and the ability, or willingness, of trainers and owners to spell horses at regular intervals (Bolwell et al. 2013; Legg et al. 2021). Most trainers in New Zealand provide early training to 2-year-olds, with the primary goals of development and education, which should prime the musculoskeletal system for future challenges (Bolwell et al. 2010). The consistency of the racing calendar also provides flexibility for many trainers to provide spells when required rather than being constrained temporally due to lack of appropriate racing opportunities (Rosanowski et al. 2015). New Zealand has low-risk racing surfaces, with predominantly turf race tracks and few races (~3%) on tracks classified as the going being fast (penetrometer, 2.0–2.5), with the going at most meetings being consistent and rated as good or dead (Rogers et al. 2014; Legg et al. 2021).

Wastage and life after racing

The loss or ‘wastage’ of racehorses is often considered one of the industries foremost welfare concerns. The median racing career for Thoroughbreds is nine (IQR 4–19) races, with three (IQR 2–3) preparations over a 2–3-year period (Legg et al. 2021), and, after lack of talent, the major reason for loss from the racing industry is musculoskeletal injury (Rogers et al. 2017b; Shrestha et al. 2021). There is also wastage due to the failure of Thoroughbred foals born to progress through to racing (Bailey et al. 1997; Wilsher et al. 2006; Tanner et al. 2013), with 33% failing to be registered with a trainer (Tanner et al. 2013). Approximately 40% of the racing population of horses exit the industry each year in New Zealand, similar to the value from preliminary investigation of Thoroughbreds in Australia (Thomson et al. 2014; Legg et al. 2021). More detailed investigation in Australia identified that 43% of these horses were, in reality, reported to still be actively participating in the industry, through spelling or training with unlicensed trainers, with a more accurate retirement metric being 17% retirements and 2.1% deaths per year (Shrestha et al. 2021). The median age of retirement of horses in both New Zealand and Australia is 5 years old (Legg et al. 2021; Shrestha et al. 2021).

The outcome for horses exiting the racing industry in New Zealand is largely unknown; however, due to the similarities between the racing industries in Australia and New Zealand, parallels may be drawn. The most frequently reported activities undertaken by retired Thoroughbred racehorses in Australia in the 2017–2018 season were equestrian or pleasure horse activities (45%), followed by participation in Australian bloodstock (30%), with only 6% of horses with unknown fates (Shrestha et al. 2021). Evidence in New Zealand supports the high rate of repurposing of retired racehorses as sport or leisure horses. Data collected suggest that approximately 45% of leisure horses and up to 55% of intermediate-level sport horses in New Zealand are described as Thoroughbred or Thoroughbred crosses (Rogers and Vallance 2009; Verhaar et al. 2014). Moreover, approximately 89% of horses competing in eventing in New Zealand are reported to be Thoroughbreds (Rogers and Firth 2005).

Traditionally there has been some laxity in the record of the official retirement of horses from racing. Since 2015, it has been mandatory for the retirement or reason for a horse to cease racing to be officially recorded (Rule 417; New Zealand Thoroughbred Racing 2021). As these data accumulate, it will become easier to identify the outcome and subsequent life after racing for these horses. Another difficulty encountered by the racing industry is the lack of national regulatory requirement to register horses in New Zealand, and the high turnover of recreation horses among owners. The industry also faces the challenge that if there is a welfare or management issue with a Thoroughbred, that the horse is often described as an ‘ex-racehorse’. This descriptor associates or implies that the racing industry is directly liable or culpable for the care of the horse throughout its life. In reality, many of these horses may have had a number of owners not associated with racing and in many situations, may have spent the majority of their lives associated with non-racing ownership and activities.

Documentation/biosecurity

In contrast to Europe, where all horses are required to obtain a passport or formal identification, there is no legal requirement to record horses with a registry or central database in New Zealand (Simmons 2015). The lack of documentation of the number of leisure horses may be considered a potential welfare issue. A lack of knowledge of the number and distribution of horses can have large implications in the event of a disease outbreak (Rosanowski et al. 2012b, 2019). For example, in Australia, the presence of a naïve equine population and a lapse in border biosecurity led to a rapid and widespread outbreak of equine influenza (Callinan 2008). The lack of information of numbers and distribution of horses in New Zealand could make containing such an outbreak difficult, and it is hence possible that a large number of horses could contract such an infection.

The movement of broodmares around New Zealand has long been recognised as a likely facilitator of the spread of infectious disease (Rogers and Cogger 2010). Improved biosecurity practices on equine properties can be an effective barrier to avoid transmission of infectious disease when horses are moved onto farms (Gildea et al. 2011). However, Rosanowski et al. (2013) reported that when 60 stud farms in New Zealand were surveyed, few biosecurity practices were identified and in the event of an infectious disease outbreak, the practices would to be inadequate at preventing disease transmission. The risk of lax biosecurity practices intensifies with the high frequency of horse and people movement among stud farms in New Zealand (Rosanowski et al. 2013).

Daily management

It is possible that pasture-based management systems are more forgiving for shortcomings in management than are intensively manage stabled horses. Surveys conducted in the UK and Australia have identified concerns with the nutritional management of leisure and sport horses associated with the prevalence of behavioural problems (Buckley et al. 2013; Ireland et al. 2013). Although published information on the topic is limited, similar welfare concerns have not been reported in New Zealand. Fernandes et al. (2014) reported that 80% of Pony Club horses surveyed had 24-h access to pasture year round, which is similar to the management of sport horses in New Zealand (Verhaar et al. 2014).

As a herd-centric species, horses are sensitive to stress associated with social isolation (Reid et al. 2017). In contrast to intensive housing systems, pasture-based management is less likely to be associated with social isolation. However, 46% of sport horses in a cross-sectional survey were reported to be kept on their own when at pasture, possibly reflecting a management strategy intended to reduce the opportunity for injury associated with horses interacting and playing with conspecifics when at pasture (Verhaar et al. 2014).

Horses managed on pasture have lower incidents of abnormal and stereotypical behaviour than do intensively managed stabled horses (McGreevy et al. 1995a; Parker et al. 2008). The lower incidences of abnormal and stereotypical behaviour observed in pasture-managed horses may be due to the opportunity to express a wider range of normal behaviours than in stabled horses (McGreevy 1997). Stereotypical behaviour in horses has been linked to a number of negative characteristics and is generally considered a sign of reduced welfare (Cooper and McGreevy 2002).

Pasture-specific welfare issues

Equine obesity has been highlighted as a welfare issue of epidemic proportions in North America, UK and Australia, affecting 30–60% of leisure horses (Buckley et al. 2013; Giles et al. 2014; Robin et al. 2015). A similar trend appears to be present in New Zealand Pony Club horses. A preliminary study by Fernandes et al. (2014) reported that 22% of Pony Club members in New Zealand scored their horse with a body condition score (BCS) of ≥7/9 (Henneke et al. 1983). A subsequent study by the same authors reported that when BCS of Pony Club horses was scored by a trained scorer, 47% were scored as ‘fat’ (BCS ≥ 7/9) and 25% presented with a cresty-neck score ≥3/6 (Fernandes et al. 2015). Ponies are efficient feed converters enabling them to maintain or gain body condition if pasture is offered ad libitum (Dugdale et al. 2011). Restricting feed intake while in a pasture-based system can be difficult because it is possible for ponies to consume over 100% of their daily energy need within 3 h at pasture (Longland et al. 2016). Obesity in horses can potentially lead to a number of health and welfare issues such as thermoregulatory inefficiency (Cymbaluk and Christison 1990), abnormal reproductive performance (Fitzgerald et al. 2003), colic (Garcia-Seco et al. 2005) and laminitis (Field and Jeffcott 1989).

Perennial ryegrass is common in New Zealand pasture (Charlton and Stewart 1999) and although seasonal variations occur, perennial ryegrass generally has a high sugar content (West et al. 2002). Horses, and especially ponies, are more prone to develop laminitis if they are managed on high-sugar pasture (Avery 1997). Interestingly, only 10% of the owners reported that their horses were prone to laminitis in the survey by Fernandes et al. (2015). This may imply some adaptation to the consistent availability of high-sugar pasture, that pasture restriction protocols attenuated the risk, or an inability of owners to identify subtle signs of laminitis.

If perennial ryegrass is infected by Acremonium lolii, the consumption of ryegrass can cause ryegrass staggers (Latch et al. 1984). Ryegrass staggers are prevalent in New Zealand (Gilruth 1906; Cunningham and Hartley 1959) and the behavioural and physiological symptoms can pose an welfare threat to the animal (Johnstone and Mayhew 2013). There are a number of products marketed to alleviate the symptoms of ryegrass staggers and the sales volume of these would indicate a concern within the sport-horse industry that ryegrass staggers may have a competition/performance-limiting effect. However, there is currently limited published information on the prevalence and management of ryegrass staggers in New Zealand horses.

Health care regulations

At present, there is no legislation requiring formal qualifications for an individual to work as a farrier in New Zealand. This is also the case in many countries with the exception of the UK where all farriers must register with the Farriers Registration Council. Farriers in New Zealand have the option to join The New Zealand Farriers Association (NZFA), which provides training and qualifications as well as promoting standards of hoof care and farriery. In a survey by Dijkstra et al. (2016), it was reported that approximately 50% of sport horses surveyed in New Zealand are shod by a farrier with qualifications recognised by the NZFA. Despite the farriery industry being largely unregulated, measurements of hoof morphology by the same authors showed a positive level of foot balance for most sport horses. Limited data are available regarding hoof health of sport and leisure horse in New Zealand; however, widespread anecdotal reports suggest a low prevalence of welfare issues. This may be attributed to the reportedly good inter-relationship between farriers and veterinarians when working on orthopaedic issues (Dijkstra et al. 2016).

In contrast to the team approach used with farriers and veterinarians, the co-ordination of treatment between veterinarians and allied health practitioners (such as equine physiotherapists, osteopaths, chiropractors and massage therapists) appears to be lacking (Meredith et al. 2011). A more holistic team approach to managing leisure and sport horses currently appears restricted to riders at the elite level (McGowan et al. 2007). Allied health therapists, mainly chiropractors (37%) or physiotherapists (24%), are nevertheless commonly used by all level of riders in New Zealand (~68% of dressage and show jumping riders). Within New Zealand, literature and legislation regarding the qualifications required for the various allied health therapies are often lacking (Meredith et al. 2011), and many riders and trainers were reportedly not aware whether their therapist was trained (22%) or had a formal qualification (49%). A previous study by Coleman et al. (2006) reported that only 44% of equine alternative therapists surveyed held a formal qualification or certificate. The skill level of a practitioner without formal qualifications cannot be guaranteed. It is of concern that over 50% of practitioners may not be adequately trained and thus pose a potential welfare risk to their equine clients.

The lack of strict regulations and quantification of efficiency of treatments may be a driver as to why few veterinarians choose to co-ordinate their treatments plan with non-veterinary practitioners. Meredith et al. (2011) reported that the main reasons for using an allied health therapist in New Zealand were to treat back pain (36%) and lameness (25%). Back pain and lameness are often inter-related (Landman et al. 2004; Murray et al. 2010) and, as such, could perhaps benefit from a team approach treatment plan. Stricter regulation of allied health practitioners, and continued research into the effectiveness of such treatments, could improve inter-relationship among veterinarians, farriers and allied health therapists and, subsequently, the welfare of horses.

Preventative health care

Previous surveys have reported that the frequency of providing preventative healthcare, such as administration of anthelmintic and dental examinations, in New Zealand is high (Rosanowski et al. 2012a; Fernandes et al. 2014). Nevertheless, frequent use of anthelmintic is potentially a long-term welfare concern because of overuse, or non-surveillance based drenching methods, and the development of anthelmintic resistance. It is now internationally accepted within the scientific community that the traditional approach to parasite control of administering re-occurring anthelmintic treatments with consistent intervals has contributed to the development of resistance (Lloyd et al. 2000; Kaplan 2002, 2004; Nielsen 2009). In addition, the development of new anthelmintics is a long and complex process. The growth of anthelmintic resistance is a concern to the equine industry as the problem has been reported worldwide (Kaplan 2004), including in New Zealand (Bishop et al. 2014).

Fernandes et al. (2014) reported that the use of vaccinations in Pony Club Horses was low compared with international standards (e.g. Ireland et al. 2013). It has been suggested that the low rate of vaccination is due to the low prevalence of infectious equine disease in New Zealand (Horner 1989). In the event of an infectious disease outbreak in New Zealand, the low vaccination rates (and high level of horse movement, paired with poor biosecurity on farms) may result in poor containment of the disease. In addition, low vaccination rates mean that many horses may have limited interaction with veterinarians, unless they become ill, since annual vaccinations are uncommon. Limited contact with veterinarians may result in potential health risks of diseases in horses not being identified early, especially among naive owners and if symptoms are vague or subtle.

Ireland et al. (2013) reported that 32% of horses in the United Kingdom had a chronic or recurrent health condition. A similar trend has not been reported in New Zealand. The management of horses on pasture appears to be associated with a lower frequency of health problems such as respiratory conditions and colic than in stabled horses (Perkins et al. 2005). Alternatively, health problems, such as those reported by Fernandes et al. (2014, 2015), may be under-reported in surveys, because owner-reported frequency may be subject to recall bias, and has been described to differ from that reported by a veterinarian (Ireland et al. 2012a). The true prevalence of health problems such as laminitis and colic in New Zealand leisure and sport horses are hard to predict without more robust quantitative data collection.

Welfare of geriatric horses

Anecdotal evidence suggests that the population of geriatric horses is growing and that their needs and risk factors may differ from younger horses (Ireland et al. 2011). With cost-effective pastoral management systems, owners may be more inclined to allow aged and/or retired horses to ‘live out their days’. Pasture-based horses are likely to be monitored less intensively and it is hence possible that early signs of poor welfare may be missed (McGowan 2011). If health problems are not identified early, the welfare of the horse could be suffering. Poor agreement of owner-reported illness compared with that detected by a veterinarian has been reported and suggests inaccurate or under-recognition of welfare problems by owners of geriatric horses (McGowan et al. 2010; Ireland et al. 2012a, 2012b).

Euthanasia

In New Zealand, the Animal Welfare Act 1999 (New Zealand Government 2022) states that ‘the owner of an animal that is ill or injured, and every person in charge of such an animal, must ensure that the animal receives treatment that alleviates any unreasonable or unnecessary pain or distress being suffered by the animal’ (section 9, p. 24). Humane euthanasia is performed on an emergency basis or elective. The first is due to an emergency situation where the horse is seriously ill or injured, such as broken limbs. The second situation is due to longer-term problems, such as age-related ailments or chronic injuries. The act of leaving a suffering animal to die of natural causes is considered to be unacceptable. Therefore, quality-of-life assessment may play an important role in informing euthanasia decisions (McGowan and Ireland 2016). Increased veterinary education and involvement and improved owner information and education could facilitate and aid management of welfare problems and quality-of-life assessment (Littlewood et al. 2021).

In New Zealand, there are no records of the number of horses euthanised annually and the act of euthanasia is poorly regulated. In many regions within New Zealand, horses can either be euthanised and buried on the farms where they lived, although a number of regional councils now prohibit this practice, because of concerns over environmental contamination with the barbiturates, and the impact on ground water. These disposal restrictions have been associated with an increasing number of commercial cremation businesses that service the equine industry.

Other common end-of-life options include sending horses to hunt clubs, or sent to pet food manufacturers (Rogers et al. 2016). Only a licenced veterinarian is authorised to euthanise a horse by lethal injection (generally sodium pentobarbital). The other methods of euthanising horses are with a firearm or a captive bolt gun. No certification is needed to euthanise animals using these two methods. However, there are Codes of Welfare stating that horses must be ‘euthanised in a manner that minimises pain and distress and the personnel undertaking the euthanasia must be competent in handling and killing horses’ (part 9, p. 31: New Zealand Government 2018). However, these standards are vague and likely to be difficult to enforce, especially for horses euthanised on farms by a layperson.

There are approximately 27 pet food manufacturers in New Zealand. Pet food manufacturers are not required to release the number of horses processed per year. However, one manufacturer reported that they received ~25–30 horses annually for processing (Rogers et al. 2016). Historically, in New Zealand, there was only one slaughter plant processing horses for human consumption, and all meat was exported. This plant processed 1530 and 1175 horses in the years 2013–2014 and 2014–2015 respectively (Ministry of Primary Industries 2016). Since 2020, this abattoir has not renewed its licence for processing horses for human consumption.

Transition from the five freedoms to the five domains

In recent years, there has been a transition from consideration of horse welfare in the context of minimising noxious or unpleasant stimuli or environmental conditions to promotion of a positive affective state. The five domains model considers both the physical and mental domains of nutrition, health, environment, behaviour and human interaction of the horse, taking into account aspects of both welfare compromise and enhancement from each domain on the overall affective state of the horse (Mellor and Beausoleil 2015). The model highlights that in addition to providing for the basic physical and behavioural needs of the horse, positive experiences (such as free movement, varied and engaging environmental challenges and clear, consistent training) can add to increasing the mental state of the horse.

Within New Zealand, the Thoroughbred racing industry has been the first to adopt this change, with the domains concept providing the underpinning of the Thoroughbred racing code of welfare (Mellor and Burns 2020). One of the challenges with this approach has been the identification of clear discrete measures of a positive affective state, which often require a holistic assessment, in contrast to negative states, which often can be identified by single markers or measures of discomfort (Bell et al. 2019). The domain approach also requires a strong reference point of the evolutionary ecological niche of the horse to avoid the temptation for anthropomorphism.