Handlers’ security and load pulling

A clear documentation precisely detailing the reasons for docking is very difficult to find. In general, in the literature devoted to Belgian draught horses, it is largely accepted that tail docking stems from problems linked to guiding horse teams for agricultural or forestry work. Schematically, a working horse team may be guided with a single rein (‘cordeau’ in French), two reins, or more, the choice of technique depending on the work to be done. In Belgium, a single rein is predominantly used. The main advantage of this technique is to allow the horse(s) to be guided with one hand, leaving the other free for other work (Brasse-Brossard, Reference Brasse-Brossard1988). Problems could rise from the tail, which may pass over the rein, impairing the control of the horse(s). However, this should not occur. Moreover, draught horses that are not under the control of the rein may still be under their teamster’s voice control. In addition, draught horses are not known to bolt easily. On the contrary, they are known for their gentleness and their docility (see e.g. the ‘National Stud farms’ descriptions for Belgium,Footnote 1 for France,Footnote 2 or Sambraus (1994) for Germany).

Another problem related to the presence of the tail is the risk of snarling between the tail and the swing bar or the leader that may be whipped.

In Belgium, as in France, docking was the traditionally chosen solution. Braiding, shaving or bandaging could, however, also have been chosen. Concerning this last technique, even if traumas have been reported due to prolonged bandaging (Professor Frank Gasthuys, personal communication), it is questionable to qualify this practice as a ‘torture instrument’ in the absence of studies evaluating the epidemiology of such lesions and pain associated with bandaging.

Despite the problems outlined above, foresters working with long-tail horses may be seen in Belgium, Italy, France or Sweden (photos and interviews in Lefebvre (2006), see also the e-site of the FECTUFootnote 3). In particular, Belgian forest teamsters generally accept the tail docking prohibition at the moment. On the other hand, in countries where horses are managed with guides (more than a single rein), tails are generally not managed, except by some hair shortening. Leaders still have a free hand, because they learn how to use their reins with one or two hands. Instances may be found in Sweden (Sidbäck, Reference Sidbäck1993) or in Germany, the homeland of Benno von Achenbach, founder of the Achenbach guide technique. For agricultural and forest work, these guides or reins may be joined in a similar way to that of ‘cordeau’. In his work devoted to this last technique, Pape (Reference Pape1980) makes no mention either to the preparation of the horses’ tail by braiding, binding or docking or to a potential risk stemming from a free tail. He, however, gives precise instructions for grooming the tail, according to its length (docked or not).

Mating aspects

In most horse breeds, the mare’s tail should be bandaged prior to mating (Taylor, Reference Taylor1998). This seems particularly necessary for Belgian draught horses due to risk of lesions to the penis of the stallion. In addition, males exhibit little enthusiasm about mating, all the more after having being injured. The authors found, however, no scientific work concluding to ‘serious lesions of the stallion penis caused by the long tail of mares’, as specified in the proposed Bill, or considering that as a major mating problem, in any horse breed. No work was found on the enthusiasm of draught male horses to mate.

In addition, some breeders refute these arguments (Lefebvre, 2006) and the following arguments may additionally be considered. From an evolutionary point of view, if the mare’s tail could actually induce severe lesions, (1) horses, or at least mares, would be at present naturally docked or ‘shaved’, owing to the fact that males would have avoided copulating with females having a long tail or tails with other ‘dangerous’ characters or (2) males would have developed a ‘defensive strategy’ consisting of a better protection of their penis against wounds potentially caused by the female tails. It is, however, possible that selection carried out by humans on Belgian draught horses led to a (i) ‘dangerous’ mare tail or to a (ii) particularly fragile male penis but these points are not mentioned in the scientific literature. In addition, if a mare’s tail, even bandaged, could cause ‘serious lesions to the stallion penis’, all mares would also be docked but they are not. In particular, other breeds of draught horses, as the French Percheron draught horse or the Britannic Shires, are not traditionally docked. In the same way, only half of the draught horses are docked in Canada, whatever the sex (Christie et al., Reference Christie, Hewson, Riley, McNiven, Dohoo and Bate2004).

From this, mares’ tails are unlikely to cause severe mating problems.

Concerning the major complications of gynaecological examinations of the mare given the ‘[impossibility] to carrying out such examinations under hygienic and sterile conditions’, the same arguments exposed for mating as stated above may be considered. In particular, such a problem is not reported for other similar draught horse breeds, such as the Percheron, Shires, Clydesdales or Suffolk Punches.

Other uses of the draught horses and renewal of the population

The size of the population of draught horses is a direct consequence of their use by humans. Due to the development of increasingly powerful and/or improved machines, the population of draught horses is currently reduced in Belgium: from about 250 000 in 1939 to about 6000 today. Even though it persists, the use of draught horses in forestry is currently questioned due to difficulties related to profitability (Thiry, Reference Thiry1994; Heidemann, Reference Heidemann2002). Load-pulling uses related to leisure have recently been developed (tourism, sport, cultural manifestations).

Because of a reduced use of traction power added to a good meat yield, draught horses are currently destined to butchery. Horses bred in this context are docked in order to emphasise the ‘meat quantity’ available in their hindquarters. This use is, however, insufficient to maintain population size, and other uses, such as landscape maintenance by grazing horses, tend to be developed (Mercat, Reference Mercat1993; Bouillot, Reference Bouillot2002). There is no evidence to suggest that these current uses require tail docking or that docking the tail in this context would increase the population of Belgian draught horses.

Cosmetic aspects

Although mainly practical reasons seem to have induced the tail docking practice in old times, aesthetic reasons cannot be dismissed (Dent, Reference Dent1983; Cregier, Reference Cregier1990). Indeed, the horses’ appearance is very important for stockbreeders. An example of horse presentation is given by Brasse-Brossard in 1945 (Reference Brasse-Brossard1988): ‘when possible, the horse should be led by a small man skilled with horses who will if the occasion arises make the horse look larger. The tail must be rolled up to make a rounded croup for all to see.’ The same author specifies that ‘one often shorten the hair of the tail of the foal, in order to more elegantly roll up the tail during work but one should not shorten as much as the Belgians who exaggerate to give the illusion of a beautiful croup.’ This last comment underlines the cultural aspect of the perception of the horses’ tail length (see also Dent, Reference Dent1983; Cregier, Reference Cregier1990; Nebergall, Reference Nebergall1999).

In this regard, according to Lizet (Reference Lizet1991), tail docking in horses began in Great Britain in the 17th century, intended to distinguish English horses from French ones and to make a distinction between these schools. Initially associated with nicking (cutting some tail’s muscles to make it stand up), it was strictly reserved for nobility. After the practise was questioned, it disappeared from Great Britain but spread in Western Europe for draught horses. Nicking, reflecting a similar aesthetic and cultural interest for horses’ tail position, led to diverse practices of artificial tail elevation, such as the use of alcohol or ginger. These practices are also currently under discussion (Colter and Luttgen, Reference Colter and Luttgen1994a and Reference Colter and Luttgen1994b; Tozzini, Reference Tozzini2003).

In conclusion, this short overview concerning uses of draught horses and cosmetic aspects illustrates the complexity of the question of the draught horse and its close link with the economic development of rural and forest areas (see also Lizet, Reference Lizet1999). In such a broad context, there is no evidence to suggest that the law on docking horses’ tails should be revoked.

Amputation procedures

For a long time, docking was carried out using tongs or sorts of guillotines and finalised by a red iron cauterisation. Currently, the operation may be carried out either surgically or by ligature. Surgical docking requires an incision of the tail’s skin and of the subjacent tissues (muscles, nerves, blood vessels and intervertebral discs). The incision is then sutured (Nebergall, Reference Nebergall1999). Ligature may use rubber rings or other binding methods. Ligature induces necrosis of the distal part of the tail. Studies comparing epidemiology of these methods and their respective pain aspects and induced complications could be useful. Comparisons of different methods of docking have been extensively studied primarily in lambs (e.g. Lester et al., Reference Lester, Mellor, Ward and Holmes1991; Graham et al., Reference Graham, Kent and Molony1997), leading to some classifications of these procedures based on acute distress responses to these procedures (Mellor and Stafford, Reference Mellor and Stafford2000; see, however, Dinnis et al., Reference Dinnis, Stafford, Mellor, Bruce and Ward1999 for limitations of such classifications).

Acute pain at the time of the amputation

Pain perception relies on complex anatomical structures and physiological mechanisms (review in Loeser and Melzack, Reference Loeser and Melzack1999; Le Bars and Willer, Reference Le Bars and Willer2004; see also http://www.vet.ed.ac.uk/animalpain/). Pain intensity experienced by other individuals, and a fortiori by individuals of other species, may be evaluated by anatomical analogies and by physiological and behavioural criteria (Bateson, Reference Bateson1991; Molony and Kent, Reference Molony and Kent1997; Weary et al., Reference Weary, Niel, Flower and Fraser2006). These criteria also help to evaluate animal welfare, a wide-ranging term including pain assessment (general aspects: review in Duncan, Reference Duncan2005; physiology: review in Axelrod and Reisine, Reference Axelrod and Reisine1984; Lightman et al., Reference Lightman, Windle, Ma, Harbuz, Shanks, Julian, Wood, Kershaw and Ingram2002; behaviour: review in Dawkins, Reference Dawkins1990 and Reference Dawkins2004; vocalisations: review in Manteuffel et al., Reference Manteuffel, Puppe and Schön2004; stereotypies: review in Mason and Latham, Reference Mason and Latham2004).

It should be noted that the measurement and perception of pain felt by animals is often subjective (Hawkins, Reference Hawkins2003) and relies on psychological factors (Bennet and Perini, 2003b; Heleski et al., Reference Heleski, Mertig and Zanella2004) and philosophical prerequisites (Rollin, Reference Rollin1985; Preece and Fraser, Reference Preece and Fraser2000; Broom, Reference Broom2006; see also open peer commentaries in Dawkins, Reference Dawkins1990). The different pain scores attributed to different species (e.g. sheep and cattle) for a same operation (e.g. castration) illustrate this subjective aspect of the perception of pain felt by animals (Scott et al., Reference Scott, Fitzpatrickt, Nolan, Reid and Wiseman2003; Heleski et al., Reference Heleski, Mertig and Zanella2004). In these studies, scores also relied on several characteristics of the persons who attributed pain scores. As a consequence, the feeling of pain in animals is not systematically taken into account (Morton and Griffiths, Reference Morton and Griffiths1985; Rollin, Reference Rollin1985; Noonan et al., Reference Noonan, Rand and Blackshaw1996a) or not taught (McGlone and Hicks, Reference McGlone and Hicks1993) and methods relieving it are insufficiently used (various species: Heleski et al., Reference Heleski, Mertig and Zanella2004; horse: Price et al., Reference Price, Marques, Welsh and Waran2002; dog: Noonan et al., Reference Noonan, Rand and Blackshaw1996a; cattle: Whay and Huxley, Reference Whay and Huxley2005).

Pain in horses at the time of the tail amputation (performed with or without anaesthesia) has not been measured. However, studies focussing on other mammals showed the painful character of amputations performed without anaesthesia. For instance, docking has been shown to be painful in dogs (review in Bennett and Perini (Reference Bennett and Perini2003); http://www.defra.gov.uk/animalh/welfare/domestic/awbillconsulttaildocking.pdf), sheep (Molony et al., Reference Molony, Kent and Robertson1993; Graham et al., Reference Graham, Kent and Molony1997; Kent et al., Reference Kent, Molony and Graham1998) and cattle (review in Stull et al., Reference Stull, Payne, Berry and Hullinger2002; Aubry, Reference Aubry2005). Both castration and docking of piglets have also been shown to induce specific behavioural changes, such as vocalisations (Noonan et al., Reference Noonan, Rand, Priest, Ainscow and Blackshaw1994; Weary et al., Reference Weary, Braithwaite and Fraser1998; Marx et al., Reference Marx, Horn, Thielebein, Knubel and Von Borell2003; Puppe et al., Reference Puppe, Schon, Tuchscherer and Manteuffel2005), activity disturbances and abnormal movements of the mutilated areas (McGlone et al., Reference McGlone, Nicholson, Hellman and Herzog1993; Hay et al., Reference Hay, Vulin, Génin, Sales and Prunier2003).

The specific case of pain in foals and newborn mammals

According to the Private Bill’s authors, pain in docked horses would be minimised by the fact that the intervention is carried out on very young foals (between 2 weeks and 3 months). That supposes that the operation is potentially painful but that very young individuals perceive the pain less than older ones. This idea of limited perceived pain in very young individuals relies on the persistent current assumption that immature nervous systems lead to weaker pain. This idea is translated into laws. For instance, the European Directive 2001/93/CE, concerning the protection of pigs, states that ‘if castration or docking of tails is practised after 7th day of life, it shall only be performed under anaesthetic and additional prolonged analgesia by a veterinarian.’ In other words, anaesthesia is not required for amputations on piglets under 7 days of life.

However, farm animals appear to be able to suffer soon after birth, when breathing oxygenates the newborn sufficiently to remove the inhibition of pain functions of the brain (Mellor and Diesch, Reference Mellor and Diesch2006). In this sense, foals of between 1 week and 6 months perceive and respond to both superficial and deep cutaneous painful stimulation, suggesting the necessity to anaesthetise them at the time of an operation (Dunlop, Reference Dunlop1994). In another study, Noonan et al. (Reference Noonan, Rand, Blackshaw and Priest1996b) showed that every pup vocalised intensely when docked. The period of most strident vocalisation corresponded to the actual moments of tail amputation, of piercing the skin for suture placement and of pressure on the suture material as the knot was tied. No more shrieks were recorded during the recovery period and puppies expressed a significant reduction of whimpers in the seconds following the operation.

Pain in foals is a subject in current development, as most pain measurements have been carried out on adults, using behavioural (Price et al., Reference Price, Catriona, Welsh and Waran2003) and physiological parameters (Hamra et al., Reference Hamra, Kamerling, Wolfsheimer and Bagwell1993; McCarthy et al., Reference McCarthy, Jeffcott and Clarke1993); the same for stress measurements (McGreevy and Nicol, Reference McGreevy and Nicol1998). In a similar way, pain in human newborns was ignored for a long time. Their capacity to feel pain and, more generally, to undergo a stress when submitted to surgical operations or diverse manipulations has been studied only relatively recently (see, for instance, Anand, Reference Anand1990; Gunnar et al., Reference Gunnar, Connors, Isensee and Wall1988 and Reference Gunnar, Hertsgaard, Larson and Rigatuso1992; Anand et al., Reference Anand, Aranda, Berde, Buckman, Capparelli, Carlo, Hummel, Johnston, Lantos, Tutag-Lehr, Lynn, Maxwell, Oberlander, Raju, Soriano, Taddio and Walco2006).

Post-operative pain and chronic health problems

Pain associated with amputation and other surgical interventions is not limited to the time of the operation. For instance, horses exhibit physiological and behavioural signs of post-operative pain during the 48-h period following an operation (exploratory celiotomy: Pritchett et al., Reference Pritchett, Ulibarri, Roberts, Schneider and Sellon2003; arthroscopic surgery: Price et al., Reference Price, Catriona, Welsh and Waran2003). Similar results in other species showed that pain related to an operation may continue from several hours (celiotomy in rat: Roughan and Flecknell, Reference Roughan and Flecknell2003) to several days (tail docking in pigs: Hay et al., Reference Hay, Vulin, Génin, Sales and Prunier2003; in lambs: Rhodes et al., Reference Rhodes, Nippo and Gross1994) after the operation. Except for the Rhodes et al. study, these results on pain duration were limited by the duration of observation, suggesting longer pain duration.

Amputations may also lead to neurological problems (Mathews and Osterholm, Reference Mathews and Osterholm1972). In this way, an increased prevalence of neuroma is observed several months after docking (lamb: French and Morgan, Reference French and Morgan1992; dog: Gross and Carr, Reference Gross and Carr1990; pig: Simonsen et al., Reference Simonsen, Klinken and Bindseil1991); neurectomy (horse: Said and Khami, Reference Said and Khami1984; rat: Fischer et al., Reference Fischer, Beggs, Shetter and Waggener1983); or beak trimming in poultry (Breward and Gentle, Reference Breward and Gentle1985; Gentle, Reference Gentle1986). Neuroma is not systematically associated with acute or chronic pain. Pain, caused by abnormal spontaneous neuroma’s activity or to increased sensibility of it (Swanson, Reference Swanson1961; Scadding, Reference Scadding1981; Blumberg and Jänig, Reference Blumberg and Jänig1984), is influenced by the healing process quality, itself relying on the type of operation, the age and the quantity of tissue removed (horse: Said and Khami, Reference Said and Khami1984; poultry: Gentle et al., Reference Gentle, Thorp and Hughes1995; Lunam et al., Reference Lunam, Glatz and Hsu1996). Skin adhesion subsequent to tail docking has also been observed in docked dogs (Carr, Reference Carr1979). An epidemiological study would complete these results in foals, where docking is still practised. Finally, infectious complications have been observed that are likely to induce paralysis in horses (Professor Frank Gasthuys; personal communication).

Pain management

In agreement with these results concerning pain stemming from amputation, authors of the proposed Bill affirm that docking may be ‘totally painless, when undergone with light sedation and epidural anaesthesia’. It should, however, be noted that inadequate depth or inappropriate use of anaesthetics and/or analgesics may lead to an insufficiently pain-free state, even if the animal is not moving during the operation (Short, Reference Short1998). Such a problem should, however, not outweigh the anatomical and physiological particularities of foals that make foals more sensitive to anaesthetics than older individuals (Dunlop, Reference Dunlop1994; Foursin, Reference Foursin1995; see also Anand, Reference Anand1990).

In addition, general anaesthesia is not risk-free. Mortality rate for horses that have undergone surgery with general anaesthesia varies from 0.68% to 8% (Lievens, Reference Lievens2001; Proudman et al., Reference Proudman, Dugdale, Senior, Edwards, Smith, Leuwer and French2006). Various factors related to the operation, like the treated disease, the type of operation, the choice of anaesthetic agents and the intervention/anaesthesia duration, influence the mortality rate (Johnston et al., Reference Johnston, Eastment, Taylor and Wood2004; Proudman et al., Reference Proudman, Dugdale, Senior, Edwards, Smith, Leuwer and French2006). Health status, age and breed (in relation with the horses’ size) of the anaesthetised animal also influence the mortality rate (Proudman et al., Reference Proudman, Dugdale, Senior, Edwards, Smith, Leuwer and French2006). In addition to increased mortality risks, general anaesthesia may also produce post-operative complications, rating between 6% and 15% (Lievens, Reference Lievens2001; Mason et al., Reference Mason, Newton, Payne and Pilsworth2005), as for instance neuropathies, myopathy, temporary blindness or post-anaesthetic colic (Lievens, Reference Lievens2001; Joubert et al., Reference Joubert, Duncan and Murray2005).

Furthermore, even if associated with lower mortality and morbidity rates (for contradictory results, see Mason et al., Reference Mason, Newton, Payne and Pilsworth2005), complementary studies could be useful concerning pain relief efficiency of epidural analgesia under clinical conditions even if efficient products are still available (Olbrich and Mosing, Reference Olbrich and Mosing2003). Additional knowledge is also needed concerning the evaluation of pain (Holm et al., Reference Holm, Wennerstrand, Lagerquist, Eksell and Johnston2006) and stress related to chirurgical operations and concerning evaluation and management of the post-operative pain (short review of analgesia in horses in Taylor, Reference Taylor2003).

Insect harassment

Many insects may bother horses, including Hymenoptera, such as bees, wasps, hornets or bumblebees. Some Arthropods are also parasites, such as various mites (Class: Arachnid; Order: Acari), including harvest ticks (Family: Trombididae), scab mites and itch mites (resp. Families: Psoroptidae and Sarcoptidae), and numerous flies (Class: Insects; Order: Diptera), including horseflies (Family: Tabanidae and some Rhagionidae) and mosquitoes (Families: Simuliidae, Ceratopogonidae and Culicidae) (Soulsby, Reference Soulsby1982; Heath, Reference Heath1994).

In addition to their parasitic aspect, inducing blood losses and potentially painful wounds when tissues are bitten or perforated, insect attacks may impair horse health, through disease transmission or allergy induction. For instance, some mosquitoes are vectors of the Orbivirus, responsible for the equine plague, and of nematodes, responsible for onchocercose, ulcers may stem from botflies attacks (Cogley and Cogley, Reference Cogley and Cogley1999) and Culicoides, in particular Culicoides obsoletus, are causal agents of a summertime skin hypersentivity usually occurring in pastured horses or in horses that are in open or poorly screened stables (Anderson et al., Reference Anderson, Belton and Kleider1991). Finally, severe insect attacks may also be detrimental to the reproductive success of horses, given that constantly harassed individuals may occasionally fail to maintain proximity or nurse their young or cease foraging (in Keiper and Berger, Reference Keiper and Berger1982; see also Byford et al., Reference Byford, Craig and Crosby1992 for effects of ectoparasites on cattle production).

It should be noted that numerous factors could influence insect attacks, as shown in sheep, where myiasis prevalence and attack level include various factors such as insect biology, including ecological factors (e.g. regional distribution of blowfly strike in French et al., Reference French, Wall, Cripps and Morgan1992), sheep management (e.g. French et al., Reference French, Wall, Cripps and Morgan1994b) or pharmacokinetic of pharmaceutical treatments (Hall and Wall, Reference Hall and Wall1995; Fenton et al., Reference Fenton, Wall and French1998a and Reference Fenton, Wall and French1998b). If demonstrated, the tail docking effect is then only one of these numerous factors, whose importance v. other factors need furthermore to be quantified.

Prevention of insect attacks: behaviour of intact horses

Horses have natural weapons against insect attacks (review in McDonnell, Reference McDonnell2003): movements of hair (mane and tail), head and neck, shivering, stamping and location shifts or refuge seeking. Defensive behaviours may be carried out alone or with conspecifics. Indeed, when in a group, two or more horses may stand beside one another, usually head-to-shoulder or head-to-tail, swishing their tails, removing insects from the head and hindquarters of the participants. Moreover, it should be noted that, even when alone, horses might protect broader areas with their tail than simply their hindquarter, notably due to their neck mobility. Lastly, like other mammalian hosts, horses might answer insect attacks by modifying the social structure (distance between individuals or group size), long-distance movements and habitat shifts (Duncan and Cowtan, Reference Duncan and Cowtan1980; Keiper and Berger, Reference Keiper and Berger1982; Rutberg, Reference Rutberg1987).

Due to differences in their biology and ecology, bothering insects exhibit various preferred zones of attack, leading horses to react differently according to the type of harassing insect. E.g. horses react to botfly attacks by moving but only those horses that take off in a gallop leave ovipositing flies behind. However, the flies are able to catch up with the horse after it comes to a stop, and this within a few seconds (Cope and Catts, Reference Cope and Catts1991; Cogley and Cogley, Reference Cogley and Cogley2000).

Prevention of insect attacks: behaviour of docked horses

The authors found no mention (1) of docking preventing (or curing) infections or insect attacks in horses or (2) of work evaluating the impact of docking on the intensity of insect attacks in horses. On the contrary, due to the positive relation between insect densities and tail swishing (Duncan and Cowtan, Reference Duncan and Cowtan1980), the frequency of tail swishing per minute was used as an indirect measure of pest harassment (Keiper and Berger, Reference Keiper and Berger1982). It has also been observed that docked individuals may walk a good deal in order to avoid bothering insects. This behaviour results in unnecessary horse fatigue, associated with unnecessary energy consumption and pasture damaging (Mr Cottrant, French Representative for Draught Horses; personal communication). In such cases, it can reasonably be concluded that the absence of a tail actually reduces welfare of pastured horses. Such a position was officially adopted in fact by the ‘Associazione Nazionale Allevatori des Cavallo Agricolo Italiano da Tiro Pesante Rapido’, the National Association for the Italian Draught Horses (Dr Pigozzi, Director of the ANACAITPR; personal communication). Finally, it should be noted that tail docking is not proposed as a preventive treatment against insect harassment in non-draught horses.

Results obtained on cattle agree with these elements (Stull et al., Reference Stull, Payne, Berry and Hullinger2002). Cattle and horses share behaviours of insect avoidance. In particular, they use their tail in a similar way (Kiley-Worthington, Reference Kiley-Worthington1976; Ralley et al., Reference Ralley, Galloway and Crow1993). Tail docking in dairy cattle may have originated for two reasons: to control disease transmission and to improve milker comfort. Tails may be contaminated with dung when cows defecate, lie down or are manipulated by handlers. Tail movements can then splatter faeces and other material onto the cow or her herdmates, contaminating udders and increasing the risks of mastitis or other udder infections. However, the effect of docking is not clearly demonstrated. Depending on studied indices, either no difference was found between docked and undocked dairy cows in udder cleanliness or health (Tucker et al., Reference Tucker, Fraser and Weary2001) or docked cows were found to be cleaner than undocked ones (Eicher et al., Reference Eicher, Morrow-Tesch, Albright and Williams2001). On the other hand, docked cows have more flies due to a significant increase in fly numbers on the rear legs. They also exhibited significantly more fly-avoidance behaviours than cows with intact tails, and these behaviours were essentially directed towards the rear. Tail swings were the most frequent fly-avoidance behaviour recorded in intact cows. Finally, docked cows stood more and exhibited increased general restlessness than intact cows when the fly numbers increased, indicating that they were uncomfortable (Eicher et al., Reference Eicher, Morrow-Tesch, Albright and Williams2001; Eicher and Dailey, Reference Eicher and Dailey2002).

Tail docking is also performed in sheep. However, the context is quite different: principal insect attacks concern the Calliphoridae and Sarcophagidae (Dipterous inducing myiasis) that are particularly dangerous because larvae grow in sheep tissues, digging in. Attacks, mainly observed in the area around the tail, seem linked to dung spread by the tail (Snoep et al., Reference Snoep, Sol, Sampimon, Roeters, Elbers, Scholten and Borgsteede2002). In such a context, docking is widely considered to prevent faecal soiling and fly strike. However, scientific studies are not unanimous: whereas French et al. (Reference French, Wall and Morgan1994a) showed that intact lambs underwent more fly attacks than docked lambs, in relation with improved rear cleanliness, two other studies (French et al., Reference French, Wall, Cripps and Morgan1994b; Snoep et al., Reference Snoep, Sol, Sampimon, Roeters, Elbers, Scholten and Borgsteede2002) showed that docking was associated neither to a lower myiasis prevalence nor to less insect attacks. In addition, docking lambs too short can increase the incidence of fly strike (Watts and Marchant, Reference Watts and Marchant1977; Watts and Luff, Reference Watts and Luff1978; see also Watts and Perry, Reference Watts and Perry1975; Watts et al., Reference Watts, Dash and Lisle1978). Furthermore, in spite of their results, French et al. (Reference French, Wall and Morgan1994a) concluded that more adequate control of diarrhoea and development of reliable alternative methods of blowfly strike management should be considered, because of the dichotomy between the proportion of docked lambs (about 100%) and the relatively low proportion of lambs likely to be struck (125 attacks for 3172 studied lambs).

Prevention of insect attacks: management of horses

Most effective solutions against insect attacks and parasitic infections appear to be preventive measures (Medica et al., Reference Medica, Hanaway, Ralston and Sukhdeo1996; Taylor, Reference Taylor1998), such as clean feeding and watering facilities and clean and fresh shelters, possibly treated with insecticides. Environmental treatment (cleared pastures, drained ponds) and pasture maintenance (regular removal of manure, periodic fallow for pastures, avoiding over-crowding of horses, avoiding the spreading of fresh manure on pastures) also limit insect attacks. Faecal sites need special attention because they enhance some insect development. In particular, they could be used as mating sites for Gastrophilus intestinalis (Cogley and Cogley, Reference Cogley and Cogley2000). Lastly, sheltering horses during the hottest hours of summer or providing them with mosquito nets or bonnets protecting eyes (the simplest being a bonnet with fringes) mechanically protect them from some attacks (Soulsby, Reference Soulsby1982). Concerning insecticides, their effective duration may be reduced by horse sudation. In addition, chemical treatments must be carefully managed in order to limit risks of insect resistance developing, as shown in sheep (Leathwick et al., Reference Leathwick, Vlassoff and Barlow1995).

Another important practice is regular close inspection (or even brushing) of horses. Although simple, but expensive in time, such a practice offers many advantages. On the one hand, it enhances prevention of many diseases related to hygiene and allows a veterinary monitoring permitting detection of any hair or skin anomaly. For instance, of the three principal mites attacking horses, Psoroptes is of particular interest in the docking question, principally attacking horses’ hair. Its prevention is clearly enhanced by regular control of skin condition (Professor Michel Ectors, vice-President of the Belgian Horse Confederation; personal communication). On the other hand, it may enhance horse welfare, likely stimulating skin functions, enhancing superficial circulation and relieving tiredness (Brasse-Brossard, Reference Brasse-Brossard1988; Heidemann, Reference Heidemann2002). Moreover, grooming enhances man–horse contacts, which is likely to improve this relation and thus the horse’s effectiveness at work (Brasse-Brossard, Reference Brasse-Brossard1988; Sidbäck, Reference Sidbäck1993).

Tail and communication

This aspect is not treated in the proposed Bill. The tail is, however, an important element of communication between horses. Tail movements can be classified into dorso-ventral movements (i.e. up and down), which are closely associated with changes in postural tonus, and lateral tail movements (tail wagging: Kiley-Worthington, Reference Kiley-Worthington1976 and Reference Kiley-Worthington1997). Tail elevation is generally associated with head and neck elevation with head and ears oriented towards the subject of interest to the animal. This elevated posture, rather than being related to a particular situation, indicates an overall vigilant state in relation to a general state of excitation, such as sexual arousal, aggressiveness or fear. It is found that tail elevation indicates a preparation for movement and an increase in pace, except for a full gallop. The explanation may be mechanical and evolutionary: preparation for movement, representing the principal defence of horses against their predators, requires the contraction of anti-gravity muscles, leading to an elevated posture. In this way, upright postures have become of communicative value to indicate a preparation for locomotion, alertness and thus warning. It is also used in confident approach and often associated with aggressive intentions (Kiley-Worthington, Reference Kiley-Worthington1976 and Reference Kiley-Worthington1997; Hutson and Haskell, Reference Hutson and Haskell1997; Rees, Reference Rees1997; McDonnell, Reference McDonnell2003; Waring, Reference Waring2003; Christensen et al., Reference Christensen, Keeling and Nielsen2005). A drop in postural tonus is shown to be related to fear, mainly in a social context and when flight is not possible. Posture of low tonus, combined often with a protective withdrawal of the tail and ears have therefore become of signal value indicating non-aggression and submission (Kiley-Worthington, Reference Kiley-Worthington1976 and Reference Kiley-Worthington1997; Waring, Reference Waring2003).

Like other demonstrative attitudes, e.g. head shaking, tail wagging likely stemmed from functional movements, such as the intention to reduce cutaneous irritation, and acquired a communication value in social and non-social contexts. Lateral tail movements may be associated with the general motivational state of the animal or to a more specific message, such as the intention to kick. They may also be seen as transitional activity between bouts of ongoing behaviour (Kiley-Worthington, Reference Kiley-Worthington1976 and Reference Kiley-Worthington1997) and produce visual as well as auditory signals (Kiley-Worthington, Reference Kiley-Worthington1976 and Reference Kiley-Worthington1997; McDonnell, Reference McDonnell2003).

Horses may display tail movements when in herd (for review of social organisation, see Linklater et al., Reference Linklater, Cameron, Minot and Stafford1999; Linklater, Reference Linklater2000) or in the presence of a human, body postures being influenced by the person present (Hausberger and Muller, Reference Hausberger and Muller2002). Humans, in particular horse workers, must thus be particularly attentive to the movements of the various parts of the horse, which gives precise information on their perception of the situation, including the horse workers’ actions. In this way, the International Federation for Equestrian Sports takes the communicative value of tail movements into account, they consider swishing the tail to be one of the ‘signs of nervousness, tension or resistance on the part of the horse [which] must be taken into account by the judges in their marks for the movement concerned as well as in the collective mark for “submission”’ (Fédération Equestre Internationale, Article 416, 2006).

Potential effects of docking on adult behaviour

From experiments on positive early handling of foals on fear of humans and manageability in older horses (Mal et al., Reference Mal, McCall, Cummins and Newland1994; Jezierski et al., Reference Jezierski, Jaworski and Gorecka1999; Henry et al., Reference Henry, Hemery, Richard and Hausberger2005; Lansade et al., Reference Lansade, Bertrand and Bouissou2005; Simpson, Reference Simpson2002; Williams et al., Reference Williams, Friend, Toscano, Collins, Sisto-Burt and Nevill2002), negative early experiences may be suspected of inversely influencing the later behaviour of horses. This has, however, not yet been studied. In addition, adult draught horses are not known for their aggressive behaviour or behavioural anomalies and one can reasonably hypothesise that duration, intensity and/or the unique character of the tail docking experience of foals are insufficient to elicit a marked and durable effect on the behaviour of adult draught horses.

On another side, neonatal pain (circumcision) has been shown to influence responses during subsequent painful procedures (vaccination) in boys (Taddio et al., Reference Taddio, Goldbach, Ipp, Stevens and Koren1995 and Reference Taddio, Katz, Ilersich and Koren1997). In the same way, a study on lambs (Kent et al., Reference Kent, Jackson, Molony and Hosie2000) suggests a long-lasting increase in pain sensitivity after an episode of intense acute pain (tail docking by rubber ring without anaesthesia). Such a point could be investigated in horses.