LIVEST1989. Livestock Production Science 1 (2001) locate/ livprodsci UNCORRECTED PROOF

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1 Livestok Prodution Siene 1 (001) lote/ livprodsi 10 Behviour of growing pigs kept in pens with outdoor runs 11 I. Effet of ess to roughge nd shelter on orl tivities 1 Anne W. Olsen* 13 Dnish Institute of Agriulturl Sienes, Deprtment of Animl Helth nd Welfre, Reserh Centre Foulum, P.O. Box 50, DK Tjele, Denmrk 15 Reeived 11 Februry 000; reeived in revised form 1 August 000; epted 9 November Abstrt 18 The im of this study ws to exmine the effets of roughge, in ddition to strw nd ess to shelter in pens with 19 outdoor runs on orl tivity towrds penmtes nd other environmentl stimuli. Seven replites, eh onsisting of 96 pigs, 0 were rised outdoors until 4 weeks of ge. At bout 10 weeks of ge the pigs were rndomly distributed to eight 1 experimentl pens with outdoor runs. The experiment ws rrnged s 3 ftoril design in the outdoor runs for eh side of the building (north/ south), nd inluding with/ without free ess to roughge (wholerop silge of brley nd pes 3 (Hordeum vulgre nd Pisum stivum ssp. rvense)), nd with/ without shelter (prtil overge). The results showed tht 4 even if the pigs hd ess to mple strw, spe nd tivity res, ess to ombintion of roughge nd shelter redued 5 penmte-direted orl tivities. However, ess to roughge in prtiulr redued redireted orl tivities nd skin lesions. 6 We suggest tht this type of roughge is n pproprite rooting substrte for pigs. 001 Published by Elsevier Siene 7 B.V. 8 Keywords: Pig-behviour; Orl behviour; Orgni frming; Housing system; Helth nd welfre Introdution In nture pigs spend most of their tive time in 39 orl tivities suh s rooting, grzing nd hewing One of the most importnt objetives of orgni nutritionl elements in their surroundings (Brieder frming in Denmrk is to onsider the physiologil mnn, 1971). However, in brren environments with 4 33 nd behviourl needs of the nimls. In Denmrk, lk of pproprite rooting substrtes, pigs often orgnilly rised pigs must be kept outside. How- rediret their orl behviour towrds pen hrdwre ever, fter wening, growing pigs my be kept nd penmtes (vn Putten, 1980). Orl tivities indoors if they hve lying re supplied with strw, direted to penmtes n led to injuries suh s free ess to roughge for rooting nd hewing, nd til-biting nd other kinds of lesions whih my ess to n outdoor run (BØJ, 1994). use pin nd helth problems for the pigs, leding 48 to eonomi losses *Tel.: ; fx: These kinds of orl tivities n often be redued 50 6 E-mil ddress: nne.olsen@grsi.dk (A.W. Olsen). by giving the pigs strw (vn Putten, 1980; Spoolder / 01/ $ see front mtter 001 Published by Elsevier Siene B.V. PII: S (01) DTD FEB :54:13.63 v

2 140 A.W. Olsen / Livestok Prodution Siene 1 (001) et l., 1995); however, the overll omplexity of the pens were loted on the north side of the building environment my lso be importnt. In this respet, nd four on the south side, eh pen with n outdoor we housed growing pigs in pens with mple strw run (deep-litter), nd spe ( m per pig), s well s Eh pen ontined deep strw re of 6. m different tivity res, to provide more diverse sunk 50 m below the level of the pen, 6% sloping environment. In these enrihed onditions we tested strw-flow re (Brue, 1990) of 3.9 m, nd if we ould further improve the pigs environment by m sltted-floor re. A two-pig self-dispenser for d giving them ess to roughge nd to n outdoor libitum feeding with erel food ws pled in the shelter. In this pper, we desribe the effets of strw-flow re, nd wter bowl on the sltted roughge nd shelter on orl behviour direted floor. The outdoor runs s well s the indoor pens towrds penmtes nd other environmentl stimuli. were eh 1.8 m, thus providing bout 1 m per Prt II of this pper will del with the pigs omfort, pig both indoors nd outdoors. The outdoor runs dunging nd temperture regultory behviour onsisted of 10.1 m onrete floor, sloping 3% (Olsen et l., 001). towrds the.7 m sltted-floor re. There, 108 wllow (1.0 m wide,.0 m long nd 0.1 m deep) 109 ws onstruted long the wll, lose to the pen Mterils nd methods entrne Animls.3. Tretments nd design Seven replites, eh onsisting of 96 LYDY- The experiment ws rrnged s 3 ftoril rossed pigs (i.e. rossbred sows of 5% Dnish design in the outdoor runs for eh side of the Lndre, 5% Yorkshire nd 50% Duro, rossed building (north/ south), inluding with/ without (6) with Yorkshire bors) were used for the investig- free ess to roughge (wholerop silge of brley tion. The pigs (hlf femles, hlf mles) were born in nd pes (Hordeum vulgre nd Pisum stivum ssp huts in n outdoor herd; they were individully rvense)), nd with/ without shelter (prtil over ermrked nd tils were left intt. All pigs in ge) replite were born in the sme week, nd were Within eh replite, shelter nd roughge were fmilir with eh other s they were rised in the ssigned rndomly to the pens on eh side of the sme or in neighbouring enlosures between whih building. The shelter ws mde of sheet of 1 78 the piglets ould ross freely. plywood ( m) pled t the pen-fixtures At bout 4 weeks of ge (men 5 7 dys, S.D. 5 m bove floor level t the end of the run, losest to ) the pigs were moved to deep-litter pens with the building wll. Roughge ws given in.7-m outdoor runs. Six weeks lter, when the pigs were long, 0.4-m wide nd 0.-m deep troughs, pled on 16 8 bout 10 weeks of ge (men dys, S.D. 5 the ground in the outdoor run furthest wy from the ) nd weighing on verge 4.4 kg (S.D ), building wll. The pigs hd free ess to roughge they were rndomly distributed to the eight ex- by supplies eh morning nd fternoon. On verge perimentl pens eh pen holding 1 pigs. They 5.8 kg (S.D ) ws distributed dily in eh were kept in the experimentl brn for n verge of trough. To prevent rin nd snow from flling into dys (S.D ) until being sent for slughter the roughge, the troughs were overed with length t men weight of kg (S.D. 5 9.). The dily of plywood bout 1 m bove floor level weight gin verged 938 g per pig (S.D ), nd 90 the rss met perentge verged 58.1% (S.D Mngement ). Before the pigs were moved into the experimentl Housing pens, onventionl strw ble ws spred in the 136 deep bedding re nd more strw ws supplied dily The investigtion ws rried out in n insulted, to the deep litter. The ombined dily men supply nturlly ventilted building (Fig. 1), where four ws.9 kg per pen (S.D ). 139

3 175 A.W. Olsen / Livestok Prodution Siene 1 (001) Fig. 1. Drwing of the experimentl brn. (R) Roughge, (C) overge/ shelter, (S) strw bedded re (deep litter), (F) strw-flow, (W) 144 wllow. The blk dots re the wter bowls (d), nd the grey boxes illustrte the lotion of the self-feeders (9). 145 The wllows were filled to the brim with ler growing pigs. The pigs dily men onsumption of wter every morning, exept when the dry bulb erel feed ws 8.5 kg per pen (S.D ) temperture ws below 08C. On hot dys, however, 148 more pigs used the wllows, the wllows flooded,.5. Behviorl mesurements nd were therefore refilled t noon. The wllows 150 were lened before filling eh Mondy nd Thurs- After moving the pigs into the experimentl brn, dy. there ws -week dpttion period before the The dung in the outdoor runs ws removed dily behviourl observtions begn in week 3, nd were by shovelling it onto the slts. The indoor strw-flow repeted in weeks 5, 7, 9, 11 nd 1. In eh of these res were shovelled when required bout one weeks, the observtions were mde between 08: week. Between eh replite ll dung nd strw nd 16:00 h on suessive dys were removed, nd the pens were pressure-wshed Diret observtions were used in reording the indoors nd out. pigs behviour. Simultneously, two different peo To ensure tht the pigs would not use the ple observed the sme niml; one person observed roughge beuse of hunger or nutritionl needs, the urrent fol pig when loted outdoors, nd the they were fed d libitum with stndrd feed for other person observed the urrent pig when indoors. 174

4 49 4 A.W. Olsen / Livestok Prodution Siene 1 (001) In dvne, the strt positions (outdoor/ indoor) of one more sn ws mde. After observing the first 9 08 the two observers were determined rndomly, nd three pigs in the first pen, we moved on to observe the observers hnged positions eh dy t noon three pigs in the next rndomly hosen pen. By use when observing 5% of the pigs (dy 1) nd gin of this method, three pigs in eh of the eight pens 3 11 fter observing 75% of the pigs (dy ). Thus, by the were observed by noon (dy 1). The proedure ws 33 1 end of eh -dy observtion period ll 96 pigs hd then repeted in the fternoon (dy 1) s well s in been observed, nd the observtions were distributed the morning nd in the fternoon (dy ), nd so by eqully between observers indoor nd outdoor on the end of eh -dy observtion period ll 96 pigs mornings nd fternoons. were observed nd the observtions distributed even The observtion order for pigs nd pens ws ly t pens on mornings nd fternoons determined rndomly in dvne. In the first rndom- Hndheld omputers (Psion Orgnizer II nd ly hosen pen, the first rndomly hosen pig ws Psion Work About from Psion PLC ( observed for 5 min by use of ll-ourrene sm-.om)) were used for dt olletion pling; however, if the pig to be observed ws not Definitions of the pigs generl tivity nd orl 4 1 tive, the next rndomly listed pig ws hosen for behviour re shown in Tble the observtion (Dybkjær, 199). The observtion of 3 the first pig ws then followed by sn to de-.6. Other mesurements 44 4 termine the pigs lotions in the different res of 5 the pen nd outdoor run. Therefter, by ll-our- Wether onditions were lso reorded. During the 45 6 rene smpling, the seond rndomly hosen pig ws sns, the outdoor observer noted wether onditions 46 7 observed for 5 min, followed by sn, then the rin, snow, wind, overst or sunshine (for eh 47 8 third rndomly hosen pig ws observed, nd finlly wether reording: yes/ no). Dry bulb temperture Tble Definitions of orl behviour nd the pigs generl tivity Behviour Definition 181 Generl tivity The pig is not sleeping (i.e. ll exept from lying pssive with eyes losed) 18 Orl behviour towrds: 183 Pen hrdwre The pig is sniffing or biting the pen hrdwre, or rooting 184 on the pen hrdwre surfe 185 Dung The pig is sniffing or rooting in distint lump of dung, 186 or distintly hewing dung 187 Strw The pig is sniffing or rooting in the strw, or distintly 188 hewing strw 189 Outdoor floor The pig is sniffing or mking ttempt to bite the outdoor onrete floor, 190 or rooting on the outdoor onrete floor surfe (with or without mterils presented) 191 Cerel feed The pig is eting feed (i.e. hving its hed inside the self-feeder) or 19 hewing while removing its hed from the feeder 193 Penmtes The pig is sniffing, hewing, suking or mking rooting movements t 194 ny prt of penmtes body in non-ggressive wy 195 Drinker Sound omes from the wter nipple while the pigs snout is pled 196 in the drinking bowl (i.e. the pig is drinking) 197 Wllow wter The pig is sniffing or hewing the wllow wter, rooting in the wter, 198 holding its snout pssive in the wter, or mking ir bubbles in the wter 199 Strw-flow The pig is sniffing or mking ttempt to bite the indoor strw-flow, or 00 rooting on the indoor strw-flow surfe (with or without mterils presented) 01 Roughge The pig is sniffing or hewing roughge, or rooting in the roughge 0 Indoor slts The pig is sniffing or mking ttempt to bite the indoor slts, or rooting on the indoor slts surfe (with or without mterils presented) 05 Rooting, the pigs snout is in ontt with the substrte while the snout is moved with forwrds nd bkwrds pointed movements, or 06 only with forwrd pointed movements.

5 341 A.W. Olsen / Livestok Prodution Siene 1 (001) nd humidity reordings were logged utomtilly The non-prmetri Wiloxon rnk sum test ws indoors nd outdoors. From now dry bulb temper- used for behviour direted to the wllows beuse 97 5 ture will be referred to s temperture only. Due to of non-norml distribution, nd for lesion sores only four reords of snow this vrible ws not beuse these were ordinl vribles (Cody nd inluded in ny nlysis. Smith, 1991) When moving to the experimentl brn the pigs Results of the wllow-direted orl behviour were weighed nd sored for lesions on til, ers nd from the non-prmetri sttistis re given in or the rest of the body (sores: 0, no lesions; 1, lesions dinry mens nd stndrd devitions, but ll other on less thn 30% of the skin re;, lesions on more results re given in lest-squre mens nd stndrd thn 30% of the skin re). In similr wy the pigs errors printed using PROC MIXED with the LSMEAN were sored for dirtiness, sun-sorh, nd ezem, sttement nd note ws mde if ny leg injury ws found. 6 This proedure ws repeted in weeks 4, 8, nd Reordings of medil tretments were mde on 3. Results regulr bsis. Orl tivities were minly ffeted by ess to Sttistil nlyses roughge, wheres only few signifint intertions 309 between roughge nd shelter emerged. Therefore, in Beuse the pen ws the experimentl unit, pen- the following, most emphsis is put onto the effets mens were lulted on the bsis of the 1 pig- of roughge mens per pen for eh behviourl mesurement Pigs hving ess to roughge spent on verge (Tble 1). All ontinuous vribles were nlysed by s/ h (S.D ) in sniffing, rooting or mixed liner models using PROC MIXED with RANDOM hewing the roughge, with no signifint effets of sttement of SAS (SAS Institute In, 1995). Clss shelter or pen lotion (P. 0.05). Pigs with ess vribles were replite (1 7), observtion week to roughge spent less time in orl behviour di (repeted mesures; 1 6), pen (1 8), side of the reted towrds pen hrdwre, dung, nd outdoor building (north/south), roughge ( 1 / ) nd shel- floor, ompred to pigs without roughge (P , ter ( 1 / ). The model sttement inluded single P nd P , respetively; Tble ) effets of roughge (df 5 1), shelter (df 5 1), side of The roughge pigs lso performed these types of the building (df 5 1), nd week (df 5 5) s generl behviour less frequently (P , P fixed effets, nd ll intertions between these nd P , respetively; Tble 3). There ws vribles if P, Rndom vribles inluded pen tendeny for less time to be spent in orl behviour nd replite nd ll intertions involving them. direted towrds strw when the pigs hd ess to Outdoor temperture (min: 4.48C, mx: C) roughge (P ; Tble ), but no differenes in 36 8 nd humidity (min: 56.8%, mx: 99.3%), number of frequenies emerged (overll men times per reordings of sunshine (min: 0, mx: 1), number of hour, S.D. 5.5). Pigs without roughge tended to rin reordings (min: 0, mx: 1) nd number of spend more time on erel feed-direted orl be wind reordings (min: 0, mx: 1) were inluded s hviours (P ; Tble ), but gin, no differ ovrites if P, Indoor temperture nd enes in frequenies emerged (overll men humidity were not inluded in the nlysis s they times per hour, S.D ), nd the mount of were highly orrelted with outdoor temperture nd erel food onsumed ws not ffeted by ny humidity (R S. 0.9, P for both). If ny tretment (P. 0.05) ovrite gve P, 0.05, the reltionship ws investi- Effet of roughge nd shelter interted with gted further by use of the prmetri (Person) regrds to durtion of orl tivities direted towrds orreltion oeffiients for the ontinuous vribles penmtes with the behviour ourring lest in pens (humidity nd temperture), nd Spermn orrel- where both roughge nd shelter were vilble (P, tion oeffiients for the ordinl vribles (wether 0.05; Tble ). This tretment ombintion lso gve reordings). the signifintly lowest frequeny of this behviour 340

6 417 6 A.W. Olsen / Livestok Prodution Siene 1 (001) Tble Durtion of different types of orl behviour (s/ h) with or without ess to roughge. Dt re lest-squre mens nd stndrd errors (S.E.) Orl behviour Tretment S.E. P-vlue direted towrds: Roughge No roughge 349 Pen hrdwre (14.3) Dung (6.48) Strw (34.6) Outdoor floor (13.) Cerel feed (31.) Penmtes b S: 96.0 S: NS: NS: Roughge intertion with shelter. S, shelter; NS, no shelter. Vlues with different supersripts re signifintly different t P, Tble Frequeny of different types of orl behviour (events per hour) with or without ess to roughge. Dt re lest-squre mens nd stndrd errors (S.E.) Orl behviour Tretment S.E. P-vlue direted towrds: Roughge No roughge 366 Pen hrdwre Dung Outdoor floor Penmtes b S: 14.1 S: NS: 17.3 b NS: Drinker b S: 1.9 S: b NS:.9 NS: Roughge intertion with shelter. S, shelter; NS, no shelter. Vlues with different supersripts re signifintly different t P, performed. Aess to both roughge nd shelter lso s ompred to ll other observtion weeks (P, gve the signifintly lowest frequeny of orl 0.05). Also, time spent on orl behviour towrds behviour towrds the drinker (P ; Tble 3), pen hrdwre, dung, nd indoor slts, inresed but there ws no signifint effet regrding the signifintly from week 3 to week 7 (P, 0.05), durtion of this behviour (P. 0.05) (on verge wheres weeks 9 1 did not differ from week s/ h, S.D. 5.1). There ws n overll tendeny However, no signifint time effet on the frequeny for pigs given roughge to spend less time in orl of these types of behviour on the pigs generl behviour direted towrds the strw-flow thn those tivity ws found (P. 0.05) not given roughge (LS-men (S.E ) vs. Pen lotion (north/ south) nd limti onditions (S.E ), P ). The frequeny of this (i.e. wether onditions, temperture nd humidity) behviour, however, ws not ffeted by ny tret- hd no effet on the pigs generl tivity, on the ment (P. 0.05). No signifint tretment effets frequeny nd the time spent drinking, or on the were found on the time the pigs spend in orl mjority of the orl tivities. However, the durtion behviour towrds the wllow wter (Wiloxon rnk of orl behviour towrds the wllow showed sum test; P. 0.05) (over-ll mens were.5 times slightly positive reltionship with temperture nd per hour (S.D ) nd 4.0 s/ h (S.D ), the number of sunshine reordings (R s nd respetively). Durtion of orl behviour towrds P, for both). Moreover, regression nlysis roughge, pen hrdwre, dung, nd indoor slts, were showed n lmost horizontl liner reltionship when ll ffeted by observtion week (P, 0.05) (Fig. ). temperture rnged from 4to 1 158C, but steep Fig. shows tht signifintly more time ws inrese when temperture inresed from 1 15 to spent in orl behviour towrds roughge in week C (P nd P respetively; Fig. 416

7 445 A.W. Olsen / Livestok Prodution Siene 1 (001) Fig.. Time spent in orl behviours towrds roughge, pen hrdwre, dung, nd indoor slts (s/ h) in the different weeks of observtion. 41 Dt re lest-squre mens6stndrd errors (S.E.). *Shows signifint differenes within eh orl behviour ompred to week 3 4 (P, 0.05). 49 3). Also polynomil reltionship ws found be- ients (R s nd Rs 5 0.6, respetively; P, tween the durtion of this behviour nd the number 0.01 for both). By using PROC MIXED nlysis we of observtions of sunshine (interept (S.E. 5 ould determine if this ws due to inresed use of ), number of sunshine observtions (S.E. 5 either the indoor or outdoor re in riny wether; ); P, 0.004). The time spent in orl behviours however, tht ws not the se (P. 0.05). Anlysis towrds pen hrdwre nd penmtes were ffeted showed tht riny wether did not ffet the pigs by riny wether (P, 0.05). A Spermn orreltion sniffing t eh other (P. 0.05). However, riny nlysis showed slightly positive orreltion oeffi- wether slightly inresed the pigs hewing, suk Fig. 3. This smoothed urve illustrtes durtion of orl behviour towrds wllow wter in reltion to environmentl temperture (8C). Eh 46 point is the men vlue from three djent degrees of temperture. The stright lines show the liner reltionship when the temperture 47 vries from 4 to 1 158C (interept (S.E. 5 4.), temperture (S.E ); P ) nd from 1 15 to 1 48C 48 (interept (S.E ), temperture (S.E ); P ).

8 537 8 A.W. Olsen / Livestok Prodution Siene 1 (001) ing, or rooting movements towrds penmtes in the Therefore, the omplexity of the pigs environment indoor re (P, 0.01) nd towrds pen hrdwre in my be importnt in voiding redireted orl be the outdoor run (P, 0.01) (R s nd Rs 5 0.6, hviour respetively; P, for both). We found tht the pigs spent. 3.% of the Pigs hving ess to roughge hd signifintly observtion time in orl behviour towrds pen lower sores for lesions on the til in week 4 hrdwre (i.e s/ h; Tble ) nd ompred to the no-roughge pigs (Wiloxon rnk 3.8% in orl tivities towrds penmtes (lowest in sum test; on verge 0.03 (S.D ) vs the group with ess to both roughge nd shelter; (S.D ); P, 0.05). Signifint differenes be- i.e. 96 s/h see Tble ). Comprtively, Lyons et tween these two groups of pigs lso emerged in week l. (1995) found tht pigs housed on strw spent s regrds lesions on the ers (0.11 (S.D ) bout % of their dytime in orl behviour towrds vs (S.D ); P, 0.05) nd the body (0.13 pen hrdwre (without strw: bout 1%). Bettie et (S.D ) vs. 0.3 (0.0); P, 0.05), wheres no l. (1993) lso found tht pigs in n enrihed other differenes between ny tretment emerged. environment spent bout 1% of their dytime in orl Aross soring times, on verge.6% of the pigs tivities towrds penmtes (brren environment: were lssified s dirty (sore 1 or more), 0.5% of 10.8%). Similr effets of strw re found in the pigs were sun-sorhed, nd less thn 1% hd younger pigs (Frser et l., 1991) nd sows (Spool ezem or suffered from leg injury. der et l., 1995), but juvenile pigs in semi-nturl There were no signifint differenes between onditions did not show ny orl tivities towrds tretments s regrds medil tretment. On verge, other pigs (Petersen, 1994). As orl behviour % of the pigs (S.D ) were treted indi- towrds penmtes is onsidered to be redireted vidully with ntibiotis for different infetions. behviour in the bsene of more pproprite stimuli However, ll pigs in replites 5 nd 6 were treted (vn Putten, 1980), ny inititive to enrih the pigs with Timulin (100 ppm) given in the feed beuse environment with pproprite stimuli is desirble the whole brn beme infeted with swine dysen- However, it is doubtful if this behviour n be tery (used by Brhyspir hyodysenteri formerly ompletely voided in indoor systems where the known s Serpulin hyodysenteri). However, we pigs, regrdless of enrihment, re kept in onfined found only few lumps of bloodstined fees, nd spe with restrited possibilities for rooting om the pigs behviour, for exmple tivity, ws not pred to pigs kept in nturl onditions. Neither different from the other replites. In generl, we indoor- or outdoor-kept pigs hve full ontrol over onsidered the pigs housed in these experimentl their environment, however, the more nturl the pens to be in good helth. onditions the more omplex the environment, giv- 51 ing pigs more hoies of wht to mnipulte, where 5 to lote themselves, nd who to soilise with. This Disussion my give more ontrol over their environment 54 ompred to pigs in indoor systems, even when they The present results show tht even when growing re enrihed. However, to mintin the pig pro pigs hd ess to mple strw, spe, nd different dution t tody s level, indoor housing is neessry, tivity res, wholerop silge of brley nd pes in but by enrihing the environment inpproprite orl ddition to strw, redued the mjority of the pigs tivities towrds other pigs my be redued orl tivities towrds their environment nd redued We found tht ess to roughge tended to redue the inidene of lesions of the skin. However, ess the pigs time spent in orl tivities towrds strw to shelter, in ombintion with ess to roughge, nd erel feed. This my suggest tht ess to redued orl behviour towrds penmtes nd the roughge ould redue ompetition for these ttr wter bowl. Consequently, both dditionl roughge tive elements in the pen. Nevertheless, no effet on nd other environmentl improvements my hve erel feed onsumption ws pprent, inditing reduing effets on redireted orl behviour in pigs. tht no-roughge pigs onsumed the erel food 536

9 65 A.W. Olsen / Livestok Prodution Siene 1 (001) more slowly, whih might be one wy of stisfying point of view. However, further studies re required their need for orl tivities. to revel if orl tivities towrds penmtes generlly The pigs ge did not influene the pigs generl re ffeted by rin tivity, but ge, however, influened the time they Bsed on the present study, we suggest tht spent on orl tivities towrds roughge, pen hrd- supplying growing pigs with roughge s rooting nd wre, dung, nd indoor slts. These orl tivities hewing substrte, in ddition to strw, might pro inresed when the pigs were weeks old (i.e. vide environmentl enrihment of biologil rele observtion week 5 7) ompred to 13 weeks of ge vne for pigs. However, how well the substrtes re (i.e. observtion week 3), but ge hd no effet when suited my depend on their omposition (see Olsen the pigs exeeded 17 weeks of ge. Similrly, et l. (000)). Therefore, types of roughge other Petersen (1994) nd Newberry nd Wood-Gush thn wholerop silge of brley nd pes my (1988) reported tht free-rnging domesti pigs improve the biologil relevne of the rooting nd generlly inresed their rooting tivities with in- hewing substrte further resing ge (mesured until week 18 nd 14, 55 respetively). Age my lso be importnt regrding 553 the effets of roughge on other orl tivities. In the 554 present study, the no-roughge pigs inresed their 5. Conlusion time spent on strw-flow-direted orl behviour in Even if pigs hve ess to mple strw, spe nd observtion weeks 5 nd 11, ompred to pigs tht different tivity res, wholerop silge of brley hd ess to roughge. The inrese in week 15 is nd pes n pprently redue redireted orl similr to the inrese in rooting behviour found in behviour, but giving them ess to shelter my semi-nturl onditions t the sme ge, but the lso redue redireted orl tivities. Therefore, the inrese in week 1 most likely ppered by overll omplexity of the environment my be n hne. Thus, our results indite tht ge (t 13 importnt ftor in voiding redireted orl behv weeks of ge) does not influene generl tivity but iour direted towrds penmtes, whih impts neg the time llotted to different orl tivities. tively on both frm eonomis nd pigs welfre Although, wether onditions, temperture nd 565 humidity did not ffet generl tivity nd most orl 566 tivities, we found steep inrese in the time the 567 pigs spent in orl tivities towrds the wllow when Aknowledgements temperture exeeded 158C, nd with inresing 569 number of sunshine observtions. This ould indite We thnk the following for their dvie: Dr. H.B tht orl tivities grdully hnged from forging/ Simonsen, Deprtment of Animl Siene nd Ani explortive rooting to rooting in onnetion with ml Helth, The Royl Dnish Veterinry nd Ag temperture regultory behviour. Andresen nd riulturl University; Drs. L. Dybkjær nd E.-M Redbo (1999) did not find reltionships between Vestergrd, Deprtment of Animl Helth nd Wel temperture nd rooting behviour in outdoor rised fre, Dnish Institute of Agriulturl Sienes; M.S growing pigs, but found inresed rooting in the J. Jsper nd Dr. Dvid Frser, Animl Welfre wllow t 08C. In this experiment, we lso found Progrm, Fulty of Agriulturl Sienes nd Cen tht inresed rin inresed the time spent on tre for Applied Ethis, University of British Colum hewing, suking or mking rooting movements bi, Cnd. The tehnil ssistne of P.M towrds penmtes in the indoor prt of the pen, nd Hgelskjær, M. Levring, L. Jensen, nd E.L. Deker, biting or rooting towrds pen hrdwre in the Dnish Institute of Agriulturl Sienes, is grteful outdoor run. If rin inreses orl tivities towrds ly knowledged. We lso thnk Hns Kier s Fund, penmtes regrdless of housing system, this my The Dnish Soiety for Animl Protetion, nd the impt the dmging behviour (e.g. til-biting), tht Dnish Reserh Centre for Orgni frming for is undesirble from both n eonomi nd welfre ontributing to the finning of this study. 64

10 A.W. Olsen / Livestok Prodution Siene 1 (001) Referenes 67 Andresen, N., Redbo, I., Forging behviour of growing 68 pigs on grsslnd in reltion to stoking rte nd feed rude 69 protein level. Appl. Anim. Behv. Si. 6, Bettie, V.E., Sneddon, I.A., Wlker, N., Behviour nd 631 produtivity of the domesti pig in brren nd enrihed 63 environments. In: Livestok Env. IV., Proeedings of Confer- 633 ene, Coventry, UK, pp Briedermnn, L., Ermittlungen zur Ativittsperiodik des 635 Mitteleuropishen Wild-shweines (Sus Srof L.). Zool. 636 Grten Leipzig 40, Brue, J.M., Strw-flow: high welfre system for pigs. 638 Frm Build. Prog. 10, BØJ, Bekendtgørelse om økologisk jordbrugsproduktion. 640 Plntedirektortets Bekendtgørelse 89 f 7. oktober 1994, 641 Ministeriet for Fødevrer, Lndbrug og Fiskeri. (Regultions 64 for orgni frming in Denmrk. Exeutive order no. 89, 643 Otober 7, Ministry of Food, Agriulture nd Fisheries, 644 In Dnish. 645 Cody, R.P., Smith, J.K., In: 3rd Edition. Applied Sttistis 646 nd the SAS Progrmming Lnguge. Prentie Hll, New 647 Jersey, p Dybkjær, L., 199. The identifition of behviourl inditors of 649 stress in erly wened piglets. Appl. Anim. Behv. Si. 35, Frser, D., Phillips, P.A., Thompson, B.K., Tennessen, T., Effet of strw on the behviour of growing pigs. Appl. Anim. 65 Behv. Si. 30, Lyons, C.A.P., Brue, J.M., Fowler, V.R., English, P.R., A 654 omprison of produtivity nd welfre of growing pigs in four 655 intensive systems. Livest. Prod. Si. 43, Newberry, R., Wood-Gush, D.G.M., Development of some 657 behviour ptterns in piglets under semi-nturl onditions. 658 Anim. Prod. 46, Olsen, A.W., Dybkjær, L., Simonsen, H.B., 001. Behviour of 660 growing pigs in pens with outdoor runs. II. Temperture 661 regultory behviour, omfort behviour nd dunging prefer- 66 enes. Livest. Prod. Si, This issue. 663 Olsen, A.W., Vestergrd, E.-M., Dybkjær, L., 000. Roughge s 664 dditionl rooting substrtes for pigs. Anim. Si. 70, Petersen, V., The development of feeding nd investigtory 666 behviour in free-rnging domesti pigs during their first weeks of life. Appl. Anim. Behv. Si. 4, vn Putten, G., Objetive observtions on the behviour of 669 fttening pigs. Anim. Regul. Stud. 3, SAS Institute In, SAS Users guide, Version SAS, 671 Cry, NC. 67 Spoolder, H.A.M., Burbidge, J.A., Edwrds, S.A., Simmins, P.H., 673 Lwrene, A.B., Provision of strw s forging 674 substrte redues the development of exessive hin nd br 675 mnipultion in food restrited sows. Appl. Anim. Behv. Si ,