Barbara Padalino, 1 Paola Zaccagnino, 2 and Pietro Celi 3,4. 1. Introduction

Transcription

1 Veterinry Medicine Interntionl, rticle ID 87551, 8 pges Reserch rticle The Effect of Different Types of Physicl Exercise on the ehviourl nd Physiologicl Prmeters of Stndrdred Horses Housed in Single Stlls rr Pdlino, 1 Pol Zccgnino, 2 nd Pietro Celi 3,4 1 Deprtment of Veterinry Medicine, University of ri, Str. prov. Per Csmssim, km 3, 71 Vlenzno (ri), Itly 2 Diprtimento di Scienze delle Produzioni nimli, Università degli Studi dell silict, Vi dell teneo Lucno 1, 851Potenz,Itly 3 Fculty of Veterinry Science, University of Sydney, P.M.. 43, Nrelln, NSW 2567, ustrli 4 Melourne School of Lnd nd Environment, The University of Melourne, Prkville, VIC 31, ustrli Correspondence should e ddressed to rr Pdlino; rrpd@iol.it Received 18 Septemer 213; Revised 13 Novemer 213; ccepted 27 Novemer 213; Pulished 22 Jnury 214 cdemic Editor: Pedro J. Ginel Copyright 214 rr Pdlino et l. This is n open ccess rticle distriuted under the Cretive Commons ttriution License, which permits unrestricted use, distriution, nd reproduction in ny medium, provided the originl work is properly cited. The im of this study ws to investigte the impcts of three different physicl exercises on the physiologicl nd ehviourl ptterns of Stndrdred trotters housed in single stlls. Twelve rcing mres were oserved twice during ech different exercise: dily trining (DT) consisted of forty minutes t slow trot (4-5 m/s) in smll trck; mximl exercise (ME) consisted of 16 m run t mximl velocity; rce (R) ws rel rce of 16 m. The mres were exmined t rest in their stll (Time I), soon fter the completion of the exercise (Time II), one hour (Time III), nd two hours (Time IV) fter the exercise. Their hert rte, respirtory rte, nd rectl temperture were recorded nd they were videotped in order to complete focl niml smpling ethogrm. ll physiologicl prmeters incresed fter exercise, in ccordnce with its intensity. fter R nd ME horses spent more time drinking, eting, nd stnding. The incidence of norml ehviours ws very low nd it ws not ffected y the different types of exercise. Overll, the ssessment of horse ehviour fter physicl exercise y mens of focl niml smpling ethogrm represents useful tool to monitor equine welfre. 1. Introduction lthough niml welfre hs ecome more importnt in the equine industry, housing systems limiting nturl ehviour ptterns re still widespred [1]. Single stlls cn confine socil interction nd locomotion to gret extent, ut, despite this, they re widely dopted in the equine industry, especilly for Stndrdred horses [2]. Housing horses in single stll cn influence equine welfre [3], with physicl exercise eing the only moment when horses cn regulrly move nd express socil ehviour. However, the possile consequences of prolonged confinement in stles on equine well-eing hve een studied [4] nd group housing systems hve een tested [5]. nimls cn dpt to new environment, ut, when horses re kept lone on flt, unstimulting squre with nothing to do, some dpttive responses might include pthy nd unresponsiveness, hyperresponsiveness, nd stereotypic ehviour [6]. pprently functionless, repetitive, stereotypic ctivities cn e seen in stle horses [7 9] nd equine stereotypies re primrily sed on feeding nd locomotory ehviours, due to mngement prctices tht limit forging ehviour nd socil contct [1]. lthough some reserchers re investigting the reltionships etween exercise, housing nd mngement, nd the development of norml ehviour in horses [11], there is lckofinformtionouttheeffectoftrditionltrining ndrcingonthestndrdredhorse sehviour.yunderstnding the ehviour modifiction tht different kinds of exercise could induce, the mngement of rcing horses could

2 2 Veterinry Medicine Interntionl e improved especilly in terms of their welfre sttus. Therefore,wesoughttoevlutetheeffectoftwodifferenttypesof exercise, s well s rcing, on some ehviourl ptterns of Stndrdred horses kept in single oxes. Some physiologicl prmeters, nmely, hert rte (HR), respirtory rte (RR), nd temperture (T), were lso monitored. 2. Mterils nd Methods 2.1. nimls, Mngement, nd Physicl Exercises. Twelve Stndrdred mres, homogeneous for live weight (45 ± 25 kg), ody condition score (3 ±.25 ritrry units; from 1 to 5 ccordingly with Mrtin-Rosset [12]), nd ge (3.5 ±.5 yers), were recruited in this study. ll mres were in good helth sttus nd they ll were qulified to rce (men record on 16 m rce trck ws 1 16 ±2 ). The reserch ws crried out on rcetrck in Cstelluccio dei Suri, Foggi (Itly), during the summer months of June nd July where the verge mximum nd minimum temperture nd reltive humidity were 31 ± 4 C, 16 ± 3 C, nd 61 ± 5%, respectively. ll mres were housed t the rcetrck in stle which contined 16 single stlls (3. m 3.5 m, 1.5 m 2 )intwo rows, with centrl isle (3 m wide). The front hs sliding doors, divided in two prts with the ottom pnel eing lwys kept shut nd the top one lwys open, when the mres were monitored for ehviourl sttus. The horses were fed with hy nd concentrte three times dy: erly in the morning (7 m), fter the completion of the physicl exercises (etween 12 pm nd 1 pm), nd lte in the fternoon (6 pm). The mount of feed, feed qulity nd type remined constnt over the course of the experiment. Wter ws ville in the stle t ll times for ech individul horse. ll mres were housed in the sme horse stlls, trined nd rced y the sme triner, nd performed the following physicl exercises t the sme time of dy during the whole study. (1) Dily trining (DT): consisted of forty minutes t slow trot (4-5 m/s) on the smll trck of the rce trck; mres would cover n verge of 1, m. The mres were jugged to hevy gig y Custom [13]. (2) Mximl exercise (ME): consisted of 16 m t mximl velocity; the mres were jugged to sulky nd they were lone on the trck. efore performing the ME, mres were wrmed up with 5, m trot t the speed of 6-7 m/s. (3) Rce (R): consisted of rel rce over 16 m distnce. ll rces were in the morning from 11 m to 1 pm (mtinee rce); DT nd ME were lso performed t similr time of the dy. The numer of the horses in ech rce ws out 14. efore the rce, horses were wrmed up with 5 m trot t the speed of 6-7 m/s. Immeditely fter ech exercise the mres were showered, wlked y n opertor for 5 minutes, nd then returned to their individul stlls. The weekly trining regime consisted ofthreedysofdtfollowedyonedyofmendthen three dys of DT gin. Horses rced every fortnight nd they rested the dy fter the rce in pddocks. During DT nd ME, horses performed the physicl exercises in n empty rcetrck, while during the rce the rcetrck hd severl specttors ehviourl nd Physiologicl Prmeters. The mres wereexminedtrestintheirstlls(timei)t8m,within 1 ± 2 minutes fter exercise, efore wshing nd cooling down (Time II), one hour fter exercise (Time III), nd two hours fter exercise (Time IV). Ech exmintion included recording the hert rte (HR) y usculttion, respirtory rte (RR) through oservtion of chest-wll movement, nd rectl temperture (RT) with n electronic thermometer in C (Vedodigit II-PIC). ll mesures were tken y the sme veterinrin. The mres were videotped y video cmer (Sony)whiletheywereintheirstlls.riefly,echoservtion cycle ws 1 hour in durtion for totl period of 4 hours, with one hour of oservtion efore exercise nd three hours oservtionfterexercise:thefirsttookplcefrom8to9m, efore the trining session (Time I), the second ws when the horse cme ck to the stll fter exercise (Time II), the third ws one hour lter (Time III), nd the lst one ws two hours lter (Time IV). etween the three oservtion periods fter exercise there ws 5-minute rek during which the physiologicl prmeters descried ove were tken. One opertor reviewed ll the videos nd compiled focl niml smpling ethogrm nd the durtion (sec) of the following ehviourl sttes ws clculted: lying, stnding, drinking, hy nd concentrte feeding, nd wlking, elimintive nd explortive ehviours. Stnding ws defined s the time spent in sttion without doing other ctivities, such s feeding or drinking, while explortive ehviour ws defined s the time tht the mres spent sniffing ech prt of the ox. Moreover, the durtion of the following events ws lso clculted: urintion, defection, hy nd concentrte feeding, nd stereotypicl nd norml ehviour. Prticulr ttention ws plced on the possile identifiction of the following norml ehviours reported for Stndrdreds: weving, ox-wlking, cri-iting/wind sucking, nd wood chewing [7]. ll mres were oserved twice for ech exercise Ethicl Guidelines. ll the procedures were crried out in ccordnce with the Itlin legisltion on niml cre (DL n. 116, 27/1/1992) Sttisticl nlysis. ll dt were normlly distriuted nd were nlysed y using REML vrince component nlysis procedure for GenStt version 14, where the type of physicl exercise (R, ME, nd DT), the time of oservtion (Times I, II, III, nd IV), nd the interction etween physicl exercise nd time of oservtion were considered s fixed fctors, while mres nd replicte were considered s rndom fctors. ll dt were expressed s men ± SE.Theeffectswere considered to e significnt t P <.5; differences etween mens were tested using lest significnt difference. 3. Results significnt effect of physicl exercise (P <.1), time (P <.1), nd their interction (P <.1) wsoserved for oth hert rte (HR) (Figure 1()) nd respirtory rte (RR) (Figure 1()). oth HR nd RR were similr efore the commencement of physicl exercise nd s expected

3 Veterinry Medicine Interntionl 3 they incresed significntly soon fter the completion of physicl exercise (Time II) nd then returned to preexercise levels y the end of the oservtion period (Time IV). significnt effect of the interction time of oservtion physicl exercise ws noted on oth HR nd RR (P <.1), with horses tht undertook the rce (R) presenting higher HR nd RR levels thn the horse tht performed the dily trining (DT) or mximl velocity (ME) exercises t Time II. HR levels were still higher in horses tht performed the R exercise compred to those tht performed the DT nd ME exercises t Time III; t Time IV, horses tht performed the R exercise hd higher HR vlues thn horses tht performed the DT exercise. Differences in RR vlues etween the rce nd the other two exercises disppered fter 1 h (Time III) from the completion of physicl exercise. significnt effect of physicl exercise (P <.1), time (P <.1), nd their interction (P <.5)wsoservedfor rectl temperture (RT) with its vlues incresing soon fter completion of the three different physicl exercises (Time II) (Figure 1(c)). This increse ws more pronounced in horses tht performed the rce. RT levels returned to preexercise levels 1 h (Time III) from the completion of physicl exercise. significnt effect of physicl exercise (P <.5) nd physicl exercise time interction (P <.1) ws oserved on stnding ctivity (Figure 2()). Stnding ehviour ws significntly lower in horses tht performed the R nd ME exercises thn in horses tht performed the DT exercise on Times II nd IV. significnt effect of time (P <.1) nd physicl exercise time interction (P <.5) ws oserved on resting ehviour (lying) (Figure 2()). Resting ehviour ws significntly lower in horses tht performed the R nd ME exercises thn in horses tht performed the DT exercise on Times II nd III. significnt effect of time (P <.1) ws oserved for drinking ctivity with horses spending higher mount of time drinking soon fter the completion of physicl exercise (Figure 3()). significnt effect of physicl exercise (P <.5), time (P <.1), nd their interction (P <.5) ws noted for eting ctivity (Figure 3()). One hour fter the completion of physicl exercises (Time II), horses tht undertook the R nd ME exercises spent more time eting thn horses tht performed the DT exercise. On Time III horses tht undertook the R exercise spent more time eting thn horses tht performed the DT nd ME exercises. Elimintive ehviours (urinting nd defecting) were significntly ffected y time (P <.1 nd P <.5, resp.) only.defectingctivitywssignificntlyhighereforethe commencement of physicl exercise (Time I; Figure 4()), while urinting ctivity ws significntly higher during Time II compred to the other times of oservtion (Figure 4()). mong the norml ehviours, cri-iting ws the only one tht ws oserved nd only in two mres. No effect of physicl exercise, time, nd their interction ws oserved for this stereotypic ehviour (Figure 5()) nd explortive ehviours (Figure 5()). 4. Discussion The good helth of the horses recruited in this study ws sustntitedytherpidreturnofthephysiologiclprmeters (HR, RR, nd RT) mesured to seline levels fter the completion of the different physicl exercises. s expected the increse in HR induced y DT ws lower thn tht induced y ME nd R. In prticulr, the HR increse ws higher in horses tht prticipted in the rce event thn those tht performed ME, even though the horses covered the sme distnce t similr speed, s the rce not only represents mximl exercise, ut it lso produces stronger emotionl response nd mentl stress [14]. Moreover, during rce event the presence of the udience might lso hve resulted in incresed stress levels [15] nd thus this emotionl influence might explin the higher increse in HR oserved in horses fter the rce. s expected, chnges in RR were proportionl to the intensity of the physicl exercises. Horses rely primrily on sweting for het loss, ut the respirtory trct contriutes to het loss especilly during exercise [16, 17]. Similrly, Mirgli et l. [18] foundpositivecorreltionetweentheincrese of RT nd exercise intensity. Since it is well known tht thermoregultion is impired in poorly trined horses [17], we cn conclude tht our horses were in good helth s their RT returned to preexercise levels within one hour from completion of the physicl ctivity. The durtion of drinking ctivity ws higher in horses fter the rce event thn fter ME nd DT exercises; this ehviour ws prticulrly evident during the first hour of oservtion, in ccordnce with Crson nd Wood-Gush [19], who lso reported n increse in the drinking ctivities soon fter n intense exercise. In our study urintions occurred predominntly during the second hour of oservtion fter exercise; likely consequence of the increse in drinking ctivity ws oserved during the first hour fter exercise, which indictes tht the horses in this study quickly chieved good stte of hydrtion. Eting ehviour ws prticulrly frequent during the first oservtion period fter the rce event nd ME. Our findings re in greement with those of Cnitz et l. [2], who proposed tht the oserved increse in time spent eting might hve een physiologicl consequence of the high energy expenditure during intense exercise. Increse in eting ehviour nd in ppetite hs lso een reported in trotters fter three-hour journey to restore the energy lost during trnsport [21]. However, our oservtions might lso hve een influenced y tht fct tht in this study horses were fsted for two hours prior to the rce nd ME events; therefore, the motivtion to et fter these exercises could hve een stronger. Resting ehviour, such s lying down or stnding while resting ws less frequent in horses fter R nd ME thn fter DT. Usully horses only lie down only in quiet environment [19]; however, in this study, when horses performed rce or ME, there were people, triners, nd drivers in their stle nd therefore the horses might hve een more lert, prticulrly fter the rce when the rce trck ws usully very noisy [22]. lterntely, the horses might hve een more ctive in their stlls in response to ctecholmines relesed during the strenuous exercise [23].

4 4 Veterinry Medicine Interntionl 8 7 Hert rte (ets/min) C Respirtory rte (reths/min) C 1 1 () 42 () Rectl temperture ( C) (c) Figure 1: Effect of different types of physicl exercise (rce lnk; mximl exercise shded; dily exercise lined) on hert rte (), respirtory rte (), nd rectl temperture (c) of Stndrdred horses housed in single stlls. Mres were exmined t rest in their stlls (Time I), immeditely fter exercise (Time II), one (Time III), nd two hours (Time V) fter the completion of exercise. Vlues re expressed s mens ± SE. For prmeters where significnt effect of type of exercise time interction ws noted, mens with different cpitl letters indicte significnt difference (P <.1) etween types of exercises. There ws no effect of type of exercise on explortive ehviour. Horses exhiit explortive ehviour to investigte new situtions nd environments [24],wheres horses well dpted to their environment nd in good welfre present decresed explortive ehviour [25]; therefore, our findings suggest tht in this study horses were well ccustomed to their environment. It is importnt to note tht explortive ehviour did not show ny sttisticl difference etween exercise types, ut ll horses showed explortive ehviours within the norml rnge nd did not mnifest ny typicl posture. Therefore, in ccordnce with tht reported y Fureix et l. [26] we cn infer tht the mres enrolled in this study did not suffer from depression. Furthermore, our findings indicte tht the incidence of norml ehviours in the horses recruited in this study wsextremelylowndthtitwsnotffectedythetype of physicl exercise. One explntion for this oservtion is tht our horses were quite young nd therefore less prone to show stereotypies in greement with chmnn et l. [27]. nother expliction could e tht the horses were well mnged nd ccustomed to the trining regime. In fct, s suggested y Houpt nd McDonnell [28], it is likely tht

5 Veterinry Medicine Interntionl c () () Figure 2: Effect of different types of physicl exercise (rce lnk; mximl exercise shded; dily exercise lined) on stnding up ctivity () nd resting ehviour () of Stndrdred horses housed in single stlls. Mres were exmined t rest in their stlls (Time I), immeditely fter exercise (Time II), one (Time III), nd two hours (Time V) fter the completion of exercise. Vlues re expressed s mens ± SE. For prmeters where significnt effect of type of exercise time interction ws noted, mens with different cpitl nd low letters indicte significnt difference (P <.1 nd P <.5, resp.) etween types of exercises () () Figure 3: Effect of different types of physicl exercise (rce lnk; mximl exercise shded; dily exercise lined) on drinking () nd eting ctivity () of Stndrdred horses housed in single stlls. Mres were exmined t rest in their stlls (Time I), immeditely fter exercise (Time II), one (Time III), nd two hours (Time V) fter the completion of exercise. Vlues re expressed s mens ± SE. For prmeters where significnt effect of type of exercise time interction ws noted, mens with different cpitl nd low letters indicte significnt difference (P <.1 nd P <.5, resp.) etween types of exercises.

6 6 Veterinry Medicine Interntionl () () Figure 4: Effect of different types of physicl exercise (rce lnk; mximl exercise shded; dily exercise lined) on urinting () nd defecting ctivity () of Stndrdred horses housed in single stlls. Mres were exmined t rest in their stlls (Time I), immeditely fter exercise (Time II), one (Time III), nd two hours (Time V) fter the completion of exercise. Vlues re expressed s mens ± SE () () Figure 5: Effect of different types of physicl exercise (rce lnk; mximl exercise shded; dily exercise lined) on stereotypic ehviour () nd exploitive ctivity () of Stndrdred horses housed in single stlls. Mres were exmined t rest in their stlls (Time I), immeditely fter exercise (Time II), one (Time III), nd two hours (Time V) fter the completion of exercise. Vlues re expressed s mens ± SE. good mngement lso contriuted to the low incidence of stereotypies. lthough housing in single stlls nd stimuli poor environment is usully positively correlted with the development of norml ehviours [7], our dt indicted tht the horses were well dpted to their routinely mngement s they were trined on dily sis, fed thrice, nd hndled mny times dy. In ddition, humn ctivities (feeding, grooming, nd clening) were conducted dily for 1 hours in the stle, suggesting tht the horses were well ccustomed to humn presence nd tht they were hndled nd looked fter properly. Finlly, the presence of few cri-iting events could e more closely correlted

7 Veterinry Medicine Interntionl 7 with the feeding other thn the trining [7]. Therefore, in greement with Werhhn et l. [11], our dt suggest tht regulr trining regime does not increse the occurrence of stereotypiesinstndrdredconfinedinsinglestlls. 5. Conclusion In conclusion, fter ll physicl exercises tested in this study, horses incresed eting nd drinking ehviour, wheres they decresed resting. In consequence, to gurntee fvourle physiologicl nd ehviourl restore, we would recommend tht horses re offered food nd fresh wter in their oxes fter cooling down. Overll, the ssessment of horse ehviour fter physicl exercise y mens of focl ethogrm represents useful tool to monitor equine welfre. This could esily e dopted y the horse industry with the use of CCTV technology. Conflict of Interests The uthors declre tht there is no conflict of interests regrding the puliction of this pper. None of the uthors of thispperhsfinncilorpersonlreltionshipwithother people or orgniztions tht could inppropritely influence or is the content of the pper. References [1] H. Werhhn, E. F. Hessel, nd H. F.. vn den Weghe, Competition horses housed in single stlls (I): ehvior nd ctivity ptterns during free exercise ccording to its configurtion, Journl of Equine Veterinry Science, vol.32,no.1,pp.45 52, 212. [2]. Pdlino, P. de Plo,. Tteo, nd P. Centoducti, L gestione del cvllo trotttore: indgine in Pugli, Ippologi, vol. 16, no. 4, pp , 25. [3] R. Freire, P. uckley, nd J. J. Cooper, Effects of different forms of exercise on post inhiitory reound nd unwnted ehviour in stled horses, Equine Veterinry Journl, vol. 41, no. 5, pp , 29. [4] J. Ldewing, The other 23 hours of the dy, in Proceedings of the 9th ISES Conference,July213. [5] M. VnDiereholock nd T. 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8 8 Veterinry Medicine Interntionl [27] I. chmnn, L. udigé, nd M. Stuffcher, Risk fctors ssocited with ehviourl disorders of cri-iting, weving nd ox-wlking in Swiss horses, Equine Veterinry Journl, vol.35,no.2,pp ,23. [28] K.. Houpt nd S. M. McDonnell, Equine stereotypes, Compendium on Continuing Eduction for the Prctising Veterinrin, vol. 15, pp , 1993.

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