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;EKIRMRKIR%GEHIQMG 4YFPMWLIVW This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned. Nothing from this publication may be translated, reproduced, stored in a computerised system or published in any form or in any manner, including electronic, mechanical, reprographic or photographic, without prior written Photos cover: permission from the publisher: Sabine Heueveldop Wageningen Academic Publishers Sarah Ralston P.O. Box 220 Manfred Coenen 6700 AE Wageningen Marco Polettini the Netherlands www.WageningenAcademic.com [email protected] ISBN: 978-90-8686-183-5 e-ISBN: 978-90-8686-740-0 The individual contributions in this DOI: 10.3920/978-90-8686-740-0 publication and any liabilities arising from them remain the responsibility of the authors. First published, 2011 The publisher is not responsible for possible damages, which could be a © Wageningen Academic Publishers result of content derived from this The Netherlands, 2011 publication. 8EFPISJGSRXIRXW

Editorial 11

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Practical news on equine for the breeder published in scientific literature between 2009-2011 15 Géraldine Blanchard

The rider’s interaction with the 21 Hilary M. Clayton

Training techniques to reduce the risk of back injury 31 Hilary M. Clayton

Equine nutrition – clinical cases where nutrition is involved 39 Manfred Coenen

Feeding and training the endurance horse: how science can serve the practitioners 49 Anne-Gaëlle Goachet and Véronique Julliand

How can we practically manage obese and ? 71 Pat Harris

Importance of the lactate parameter for performance diagnosis and for the regulation of training in top competition athletics and in recreational sports 91 Ulrich Hartmann

Performance diagnosis and training monitoring of human athletes in track & field running disciplines 113 Ulrich Hartmann and Margot Niessen

Practical news on advances in nutrition for performance horses and ponies between 2009-2011 135 Véronique Julliand and Sarah L. Ralston

)2986%'3   Do animals use natural properties of plants to self- medicate? 159 Sabrina Krief

Feed supplements to maintain performance and health 171 Kenneth Harrington McKeever

Will total mixed rations be the future of horse feeding? 185 Sarah L. Ralston and Harlan Anderson

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Effect of a complementary horse feed on nervous horse behaviour 195 M. Barbier, S. Benoit and J.L. Lambey

The effect of caecal pH on in vivo fibre digestibility in Norwegian trotter horses 205 C. Brøkner, D. Austbø, J.A. Næsset, K.E. Bach Knudsen and A.H. Tauson

Effect of 5 week training period on the glycemic and insulinemic response to a cereal meal in Standardbreds 213 A.G. Goachet, C. Philippeau, V.J. Adams, V. Julliand and P. Harris

The use of equine K4b during incremental field exercise tests in driven Standardbred trotters: a preliminary study 221 A.G. Goachet, J. Fortier, V. Julliand, H. Assadi and R. Lepers

The effects of a high , cereal-based diet compared to a low starch, fibre-based diet on reactivity in horses 227 C.E. Hale, A.J. Hemmings and S.E. Bee

A marine supplement for Aquacid™ 233 B.D. Nielsen, E.C. Ryan, C.I. O’Connor-Robison

  %TTPMIHIUYMRIRYXVMXMSRERHXVEMRMRK High level endurance training: descriptive study based on the follow-up of the French team over seasons 2009 and 2010 235 C. Robert, L. Mathews-Martin and J.L. Leclerc

Workload during an eventing competition 243 E. Valle, R. Odore, P. Badino, E. Fraccaro, C. Girardi, R. Zanatta and B. Bergero

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We made it: the 4th Equine Nutrition and Training Conference is up and running! Proof is this book. My congratulations and gratitude to all those involved, with special mention of our partners from Vetoquinol/ Equistro as well as Lohmann Animal Health/Lonza! I thoroughly enjoyed organising and even more so the hosting of this meeting and wish to be able to hold another one in 2013! With a ‘little help of my friends’ this should be made possible!

The aim of the articles in this book is to present and discuss the latest scientific findings on nutrition and training of horses (News) and to provide practical advice to the readers. It would be too much of a challenge to present everything on nutrition and training in one conference, and therefore, the selection of the references in the articles on News depends on the authors’ choices. Combined with the discussions during the conference these presentations should allow the participants a good insight into each one of the selected subjects (please also join us in 2013!). The articles on practical advice are very informative and functional, including in some cases that (practical) information is lacking or statistically insignificant but practically very relevant.

Finally, the expanded abstracts on actual and focused research aspects are of excellent additional value to the section on nutrition and training of horses in the book. Thank you very much to these authors for submitting the work in the definite format, going through the reviewing process to present at the conference and the willingness to publish the work in this book!

I wish that all those reading the articles find lots of interesting and useful information! Please send me an e-mail ([email protected]) and comment on what you would be interested in! Maybe we can consider it for 2013!

Wish you health and fun! Arno

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Géraldine Blanchard Animal Nutrition Expertise SARL, 33, Av. de l´ile de France, 92160 Antony, France; [email protected]

After wide considerations of the ’s growth in the early 2000’s, recent publications concerning breeding have focused on a variety of topics that we’ll consider in the chronology of breeding. Starting with and , the potential interactions of nutrition and fertility can be examined considering the athlete or racing career on one hand, and the body condition and metabolism on the other hand. The relationship between nutrition and the oestrus cycle and fertility, especially in the maiden is an interesting and practical approach. Then the interaction between the mare’s nutrition and the foal’s metabolism has been studied. The third topic is on the supplementation of the or the mare, and the consequences on the foal’s health. Clinical nutrition will close this review.

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Stallions and mares may have two parallel careers, one as a genitor, and one as an athlete, that could affect each other. To evaluate the effects of racing on fertility in Standardbred and , the career of stallions and mares were followed in not less than 75,000 mares (Sairannen et al., 2011). In these two breeds the genetic correlation between best racing record and fertility was weak or negligible, at least in this study. It showed also that the stallion fertility did not suffer from racing during the mating year. But for mares, the situation may be much more diverse. The most negative situation was for mares, racing after the first mating or more than 10 times during the mating year, as it diminished the foaling outcome. However, racing only before the first mating or 1 to 5 times during the mating year had positive effects on mare fertility. Finally, the mares with the best career racing records had the highest foaling rates. The

A. Lindner (ed.), Applied equine nutrition and training,  DOI 10.3920/978-90-8686-740-0_1, © Wageningen Academic Publishers 2011 +qVEPHMRI&PERGLEVH

authors emphasized that this feature was probably due to preferential treatment (nutrition, environment, close follow up of fertility…). If this explanation is confirmed, that would signify that the best care may compensate a demanding situation in the mares with the best potential. But to estimate the variable with the highest impact, more data will be necessary including studies of other breeds or race types than Finnhorse and Standardbred.

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Mares can suffer from being overweight, with consequences on their and insulin metabolism and the risk for metabolic syndrome. Standardbred maiden mares are considered stressed and in poor physical condition at the end of their racing careers, due to incorrect management (Vecchi et al., 2010). The estimation of body condition score (BCS) and thickness by ultrasound method provided similar results. In Standardbred maiden mares of various ages, both BCS and fat thickness were significantly and reciprocally correlated to the time of first seasonal ovulation. In other terms, in stressed maiden mares with low condition score, a flushing or nutrition plane started about 3 weeks before the breeding season may stimulate ovarian activity (Vecchi et al., 2010). These data, together with data on mares (Dugdale et al., 2010) which confirm the huge potential appetite of mares, should encourage feeding mares properly but not excessively all year long, adapting the diet to maintain a proper body condition.

Even if in breeding areas, the use of is maximized, concentrate feeding is usually considered beneficial to mares (Karren et al., 2010), and often necessary, at least to provide , trace-elements and lacking in . Beside forage, supplement feeds may be provided. But the mare’s tolerance for starch might differ with .

Starch-rich feed supplements appear to be better tolerated by pregnant than non-pregnant mares (George et al., 2011). This applies for mares of optimal body condition. The fact that pregnancy enhances glycemic and insulinemic effects of starch-rich concentrate may be explained by the increased requirements, including energy and glucose requirements associated with pregnancy in all mammal females. But if the mare receives a high level of starch-rich feeds, the effects on the

 %TTPMIHIUYMRIRYXVMXMSRERHXVEMRMRK  4VEGXMGEPRI[WSRIUYMRIRYXVMXMSRJSVXLIFVIIHIV mare and the foal’s metabolism have to be considered. The number of meals may also have an impact. This has been partly answered in from mares receiving two-thirds of their diet from low or high starch feed in late gestation. The offspring showed a significant difference in glucose 80 days after birth, but always within normal range, and a trend in insulin sensitivity at 160 days (George et al., 2009). More data on the long-term consequences of this trend are required to understand the importance of the findings.

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Anti-oxidant supplementation of stallions may have an impact on the semen characteristics. In the case of a basic diet, the addition of organic selenium, E and in stallions lead to an improvement of various sperm characteristics: velocity, straightness, viability, progressive motility, accompanied by an increase of the total seminal plasma antioxidant level and a decrease of abnormal sperm morphology (Contri et al., 2011). These positive consequences may appear quite late, only after 30 to 60 days of supplementation. However, to prevent any negative over supplementation, at first, the composition of the entire diet of the stallion must be considered before adding selenium and other anti-oxidants.

Mares and foals benefit from receiving a mix fed providing 100% and furthermore 120% of the selenium amount recommended by the NRC (National Research Council, USA). The mare’s colostrum and the foal’s plasma and muscle show a higher selenium concentration with supplementation of the mare during the 110 days preceding parturition (Karren et al., 2010). But selenium supplementation had no effect on foaling variables and on the composition of colostrum (Thorson et al., 2010). Furthermore, mares on pasture with no feed supplementation showed the greatest IG concentration in colostrum. However, this must be interpreted with caution, considering the composition of the feed. The supplementation with anti-oxidants can not be limited to the concentration of the trace-element in body fluids (Calamari et al., 2010; Muirhead et al., 2010). Finally, in mares as in stallions, prior to adding supplemental selenium, concentrate feed must be evaluated in order to consider the total amount of .

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Two reviews are of interest, one for pregnant and lactating pony mares, especially overweight ones, at risk of hyperlipemia while losing appetite (McKenzie, 2011), and one for feeding management of the sick foal (McKenzie and Geor, 2009).

Due to the lack of information on the young foal requirements especially when sick, foals’ nutrition is a challenge for breeders, practitioners and even nutritionists. A review of the feeding management of the sick foal is available (McKenzie and Geor, 2009), including enteral nutrition, enteral support and how to provide it, from the neonate to weaning, parenteral nutrition including short term caloric supplementation, formulation, administration and monitoring of parenteral nutrition and insulin therapy when required. As an example, the foals energy requirement, including basal metabolism and growth, is about 150 kcal/kg body weight/day in neonates, and decreases progressively to 80 to 100 kcal/kg body weight/day by 1 to 2 months of age. Due to the difference between mare’s (about 64%, 22% and 13% of dry matter as , , and fat, respectively) and cow milk (about 38%, 26% and 30% of dry matter as sugar, protein, and fat, respectively), the feeding of the foal has to be specific and requires the endogenous production of insulin by the pancreatic b-cells. This function is related to endocrine function, itself linked to the composition of the milk. The foal’s nutrition characteristics are still not fully known, and the management of the sick foal must include at least what is already understood, even if it would require further work.

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Calamari L, Abeni F, Bertin G (2010) Metabolic and hematological profiles in mature horses supplemented with different selenium sources and doses. J Anim Sci 88:650-659. Contri A, De Amicis I, Molinari A, Faustini M, Gramenzi A, Robbe D, Carluccio A (2011) Effect of dietary antioxidant supplementation on fresh semen quality in stallion. Theriogenology 75:1319-1326. Dugdale AH, Curtis GC, Cripps PJ, Harris PA, Argo CM (2010) Effects of season and body condition on appetite, body mass and body composition in ad libitum fed pony mares. Vet J (in press).

 %TTPMIHIUYMRIRYXVMXMSRERHXVEMRMRK  4VEGXMGEPRI[WSRIUYMRIRYXVMXMSRJSVXLIFVIIHIV

George LA, Staniar WB, Treiber KH, Harris PA, Geor RJ (2009) Insulin sensitivity and glucose dynamics during pre-weaning foal development and in response to maternal diet composition. Domest Anim Endocrinol 37:23-29. George LA, Staniar WB, Cubitt TA, Treiber KH, Harris PA, Geor RJ (2011) Evaluation of the effects of pregnancy on insulin sensitivity, insulin secretion, and glucose dynamics in mares. Am J Vet Res 72:666-674. Karren BJ, Thorson JF, Cavinder CA, Hammer CJ, Coverdale JA (2010) Effect of selenium supplementation and plane of nutrition on mares and their foals: selenium concentrations and glutathione peroxidase. J Anim Sci 88:991-997. McKenzie HC (2011) Equine hyperlipemias. Vet Clin North Am Eq Pract 27:59-72. McKenzie HC, Geor RJ (2009) Feeding management of sick neonatal foals. Vet Clin North Am Eq Pract 25:109-119. Muirhead TL, Wichtel JJ, Stryhn H, McClure JT (2010) The selenium and vitamin E status of horses in Prince Edward Island. Can Vet J 51:979-985. Sairanen J, Katila T, Virtala AM, Ojala M (2011) Effects of racing on equine fertility. Anim Reprod Sci 124:73-84. Thorson JF, Karren BJ, Bauer ML, Cavinder CA, Coverdale JA, Hammer CJ (2010) Effect of selenium supplementation and plane of nutrition on mares and their foals: foaling data. J Anim Sci 88:982-990. Vecchi I, Sabbioni A, Bigliardi E, Morini G, Ferrari L, Di Ciommo F, Superchi P, Parmigiani E (2010) Relationship between body fat and body condition score and their effects on estrous cycles of the Standardbred maiden mare. Vet Res Commun 34 Suppl 1:S41-S45.

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Hilary M. Clayton Mary Anne McPhail Chair in Equine Sports Medicine, Professor of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; [email protected]

The rider communicates with the horse on several levels, some of which can be measured mechanically. To date, most of these studies have involved using electronic pressure mats to measure pressure distribution on the horse’s back and strain gauge transducers to measure tension in the reins. The results are providing information that can be used to develop an understanding of the mechanics of the rider’s interaction with the horse.

The horse’s thoracolumbar spine behaves as a beam suspended at each end by the forelimbs acting through the thoracic sling muscles, primarily serratus ventralis, and by the hind limbs acting through the pelvic girdle. The middle part of the beam tends to sag due to extension of the intervertebral joints under the influence of gravity. The amount of intervertebral extension is controlled by passive (ligamentous) and active (muscular) tension. When a weight is added to the horse’s back, it causes the intervertebral joints to extend further bringing the dorsal spinous processes and the articular facets into closer approximation with the consequent risks of impinging spinous processes and facet arthritis. Thus, trainers should teach the horse to maintain roundness of the back under the rider’s weight to reduce the risk of spinal injury and associated back pain. The head and neck act as a beam that extends out in front of the body mass and stabilized at its base. During locomotion the base of the neck moves with the horse’s shoulders but the upper neck oscillates under the effects of gravity and inertia. These movements affect the horse’s contact with the .

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The force of the acting on the horse’s back is measured using an electronic pressure mat inserted between the saddle and the horse’s back. In the McPhail Equine Performance Center, we use the Pliance mat (Novel Electronics Inc., St. Paul, MN, USA) which has been shown

A. Lindner (ed.), Applied equine nutrition and training,  DOI 10.3920/978-90-8686-740-0_2, © Wageningen Academic Publishers 2011 ,MPEV]1'PE]XSR

to provide accurate and reliable data (De Cocq et al., 2009), which is not the case for all types of pressure mats. The Pliance mat has 256 sensors distributed in two rectangular mats that are placed on the left and right sides of the horse’s back. They are separated across the dorsal midline to avoid the problem of having sensors activated by the sides of the mat being pulled downwards which might suggest that the saddle is impinging on the dorsal spinous processes when this is not the case. Forces registered by the sensors are transmitted to a laptop computer using Bluetooth technology. Since there are no wires connecting the mat to the computer, the horse and rider can move freely while pressures are being measured. The Pliance software calculates the total force on the horse’s back by adding the forces on all the individual sensors and provides a colour-coded map of the pressure distribution. A drawback in the use of the saddle mat is that the sensors only register forces that are applied perpendicular to their surface. Shear forces are not measured but can contribute significantly to damage to the skin.

The pressure pattern on the horse’s back is displayed in color on the computer screen with black representing the lowest pressure and increasing through blue, cyan, green, yellow, red and pink, which represents the highest pressure. Three types of graphs display the pressure patterns (Figure 1). Numerical analyses are facilitated by subdivision of the total area of the mat transversely (left and right halves) or longitudinally (front, middle, rear sections). The mat provides dynamic data during ridden exercise with real time display of the changing pressure patterns on the computer screen. However, this also complicates the process of analysis since each stride is represented by numerous data points for each sensor. One of the challenges for researchers is to develop analytical procedures that take account of both the spatial and temporal distribution of the forces and pressures on the horse’s back.

Saddle fit can be evaluated qualitatively by an experienced saddle fitter under static conditions. The electronic pressure mat has the advantages of measuring the pressure not only at rest but also during locomotion at different gaits.

A well-fitting saddle shows pressure distributed evenly over long, wide panels. When the tree is either too wide or too narrow, the

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The use of a pad between the saddle and the horse’s back may even out the pressure in that are basically the correct size and shape. Sheepskin has performed particularly well in my own studies (Figure 3) and Kotschwar et al. (2010a) have shown a similar beneficial effect with reindeer fur pads in saddles that are basically a good fit for the horse. In poorly fitting saddles, however, different types of pads were beneficial at different gaits. For example, when the saddle tree was too wide, foam and gel pads were most effective at walk whereas gel and reindeer fur were more effective at trot (Kotschwar et al., 2010b).

The tree of the saddle distributes the weight of saddle and rider over a large area of the horse’s back. This is in contrast to riding with a treeless saddle or riding bareback when the forces are concentrated beneath the rider’s ischial tuberosities.

One of the essentials of riding is to mount the horse. During mounting, the highest total force occurs as the rider’s leg swings over the horse’s back and this force was significantly higher when the rider mounts from the ground compared with using a mounting block. More importantly, the pressure distribution during mounting is highly asymmetrical on the left and right sides. Pressure is highest on the right side of the withers, which stabilizes the saddle as the rider puts weight on the left stirrup. The left side of the withers is unweighted but there is an area of high pressure on the horse’s left shoulder. The horse

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 %TTPMIHIUYMRIRYXVMXMSRERHXVEMRMRK  8LIVMHIV´WMRXIVEGXMSR[MXLXLILSVWI braces himself to withstand this asymmetric loading pattern, and it is easy to speculate that this could be associated with uneven muscle development in the left and right shoulders, which is frequently identified by and saddle fitters. It is recommended that riders should mount without using the stirrup by either getting a leg up or by using a high enough platform to step onto the horse without using the stirrup. If there is no option to mounting using the stirrup, a mounting block should be used and the rider should switch between mounting from the left and right sides. This will be a positive step toward making the horse straight and symmetrical.

There are large differences between riders in how much force they apply to the horse’s back when they land in the saddle; a soft landing is definitely preferable from the horse’s standpoint. Some riders have a habit of stepping down forcefully into the right stirrup to center the saddle which has been pulled to the left side during mounting. This is associated with high forces on the horse’s back.

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Rein tension is easily measured using strain gauges inserted into the rein (Clayton et al., 2005). These sensors measure rein tension dynamically but are unable to distinguish whether the tension originates in the rider pulling on the rein or the horse pushing against the bit. A study using side reins in horses trotting in a straight line showed that there are two peaks in rein tension during each stride of trot and these occur during the diagonal stance phases. The tension increases are caused by the fact that the head and neck nod downwards under the influence of gravity and inertia during the stance phases. Minimal tension, maximal tension and mean tension are all useful measurements that provide different types of information about the rein contact. All three tension variables increase as the reins are shortened. Minimal tension increases and maximal tension decreases with elasticity of the rein (Figure 4) (Clayton et al., 2011).

When a rider is present, riding style has a large effect on tension recordings. For example, dressage training requires the horse to seek contact with the bit resulting in higher rein tension values than for horses trained, for example, in in which the reins hang loosely. These stylistic differences make it difficult to compare results

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across different studies. My own studies using horses trained in dressage have shown two distinct tension peaks during each stride of trot, whereas at canter there are three peaks per stride, one large peak flanked by two smaller peaks that represent the three-beat rhythm of the canter. In some riders the left and right reins show very similar magnitude and timing of the rein tension oscillations, other riders have differences in the magnitude of left and right rein tensions or in the timing of the tension changes on the left and right sides.

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Radiographic and fluoroscopic studies (Clayton and Lee, 1984; Manfredi et al., 2005) have investigated the position and action of different bits in the horse’s mouth. The more recent series of studies used the bits shown in Figure 5. The corresponding lateral radiographs are shown in Figure 6.

The mouthpiece of the single jointed snaffle hangs downwards on the tongue with the joint protruding toward the roof of the mouth where it can put pressure on the underlying bone of the hard palate. When tension is applied to the reins, the mouthpiece becomes more deeply embedded in the tongue, so it moves away from the palate.

The KK Ultra is a double-jointed bit with a short oval-shaped middle piece. Unlike a single jointed snaffle, it has a smooth surface facing toward the palate. Rein tension moves the entire mouthpiece of this bit away from the palate by compressing the tongue. The relatively large separation of the metal from the palate, combined with the

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smoothness of the surface of the central link, may explain why many horses perform well in this bit.

The Baucher bit has an upper ring for attachment of the cheek pieces and a lower ring for attachment of the reins, which gives the bit a more stable position in the horse’s mouth when tension is applied to the reins. The joint lies close to the palate and, since the mouthpiece has relatively little mobility, it is difficult for the horse to move this bit inside the oral cavity. Consequently, this may be an uncomfortable bit for some horses.

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The two arms of a Myler bit meet within a central barrel that allows a swiveling motion but does not permit any nutcracker action. All three Myler mouthpieces were positioned relatively high on the tongue and the barrel prevents any squeezing action on the tongue. The horse may be able to use his tongue to push against the mouthpiece, giving him a degree of control over the position of the bit and the areas affected by pressure.

Fluoroscopic analysis of the horses’ behaviours with the different bits with loose reins and with tension applied to the reins showed a range of intra-oral behaviours that included opening the mouth, retracting the tongue beneath the bit, bulging the middle part of the dorsum of the tongue over the bit and using the tongue to raise the bit between the premolar teeth (Manfredi et al., 2010). Behaviours other than holding the bit quietly in the mouth or chewing gently increased when tension was applied to the reins. The behaviours shown were consistent within each individual horse when wearing different bits but were not specific for the type of bit.

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Clayton HM, Lee RL (1984) A fluoroscopic study of the position and action of the jointed snaffle bit in the horse’s mouth. J Eq Vet Sci 4:193-196. Clayton HM, Singleton WH, Lanovaz JL, Cloud GL (2005) Strain gauge measurement of rein tension during riding: A pilot study. Eq Comp Exerc Physiol 2:203-205. De Cocq P, Clayton HM, Terada K, Muller M, van Leeuwen J (2009) Usability of normal force distribution measurements to evaluate asymmetrical loading of the back of the horse and different rider positions on a standing horse. Vet J 181:266-273. Geutens CA, Clayton HM, Kaiser LJ (2008) Forces and pressures beneath the saddle during mounting from the ground and from a raised mounting block. Vet J 175:332-337. Harman J (1997) Measurement of the pressures exerted by saddles on the horse’s back using a computerized pressure measuring device. Pferdeheilkunde 13:129-134. Kotschwar AB, Baltacis A, Peham C (2010a) The effects of different saddle pads on forces and pressure distribution beneath a fitting saddle. Eq Vet J 42:114-118. Kotschwar AB, Baltacis A, Peham C (2010b) The influence of different saddle pads on force and pressure changes beneath saddles with excessively wide trees. Vet J 184:322-325.

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Manfredi JM, Rosenstein D, Lanovaz JL, Nauwelaerts S, Clayton HM (2010) Flouroscopic study of oral behaviours in response to the presence of a bit and the effects of rein tension. Comp Exerc Physiol 64:143-148. Manfredi J, Clayton HM, Rosenstein D (2005) Radiographic study of bit position within the horse’s oral cavity. Eq Comp Exerc Physiol 2:195-201. Meschan E, Peham C, Schobesberger H, Licka T (2007) The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle. Vet J 173: 578-584.

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