Research Note

Furnished cage system and hen well-being: Comparative effects of furnished cages and battery cages on behavioral exhibitions in White Leghorn

K. Mile* and H.-W. Chengf'

*Depai.tirient of Animal $renc:es. Purdue University. Wet Lafayette, IN 7907: (lad TLicstocJi Behacior Research Unit. USDA -Aqricuitwr'al Research Service. West Lafayette. IN 47907

ABSTRACT The system is being banned birds were housed per cage, providing a stocking den- ill before or by 2012, and the fur- sity of 610 (-Ili 2 of floor space per bird. Behavioral ob- nished cage system will be the only cage system allowed servations were conducted using the Xoldus Observer after 2012. This stud y was conducted to exanune the software package. The birds were observed at 5-mm different effects of caging s ystems, furnished ('ages vs. intervals for the entire light period. The birds housed in battery cages, oil behaviors. One hundred ninety- battery cages had higher posture and behavioral transi- two 1 -d-old non-beak-trinuned I-Tv-Line \V-36 White tions and increased time spent walking and perform- chicks were reared using standard nianageinent ing exploratory behavior (P < 0.05. 0.01. respective- practices in raised wire cages. At 19 wk of age, the birds ly) which may indicate they were stressed. resulting were randomly assigned into battery cages or furnished iii restlessness. whereas the birds housed in furnished cages. The battery cages were commercial wire cages ('ages had higher levels of preening ( P < 0.05). Preen- containing 6 birds per cage. providing 645 cm2 of floor ill-- has been considered as a comfort behavior ill birds. space per birds. The furnished cages had wire floors hese results may suggest that furnished cages may be and solid metal walls, with perches. a dllsthathi]lg area, a favorable alternative 5 stein for housing birds by al- scratch pads, and a nestbox area with a. concealiiient. lowing them to perform certain natural behaviors. curtain. Based oil company recommendations, 10 Key words: . battery cage. behavior, , well-being 2009 Science 88:1559 1 564 doi:10.3382/ps. 2009-00045

INTRODUCTION be housed in strict confinement with highly mechanized feed and water systems with manure and collected Chickens are social animals and live iii a small group ammi onia.ticallv (Cooper and Albent usa. 2003). In this in nature. Ti ev spend a lot of t ime scratching and for- case. battery cages benefit both the birds and pro- aging for food oil ground and perform heritable ducers. However, there, is considerable morphological. behaviors such as dustbathing and prela ying nesting. In physiological. and behavioral evidence demonstrating the coinniercial poultry industry, in the United States stress reactions in chickens reared in the battery cage and glolallv, layers are primarily housed in battery cag- systems because there are no significant changes in es (also called conventional cages). Worldwide. battery birds' biological and behavioral characteristics through cage svstenis elicit a great deal of debate pertaining selectivel y breeding for productivity (Folsch and to the relative effect of the practice on bird well-being Vestergaard. 1981; Rogers. 1995). Domestic birds (Dawkins et al.. 2001). The bestowed benefits are of may still prefer to perform certain natural behaviors; maintaining a small group size, with a low level of so- however, within the battery cages, the birds behav- cial stress, resulting in low aggression and cannibalism. ior repertoire is restricted and hone qualit y is reduced lngh egg production, and increased hygiene, which may by the overcrowding and barren environment (Hughes indeed favor improved well-being iii caged birds (Ap- et al.. 199:3: Baxter, 1991; Fleming et al.. 1994; Nicol, plebv. 1998). In addit 1011. economically. batter y cages 1995: Vestergaard et al.. 1997: Tauson. 1998). Because are highly efficient because large numbers of birds can of those effects, there is growing pressure Ii'oni am iii nal well-being and consumer groups advocating the ban- niiig of battery cage systems iii the poultry industry. 2009 Poultr y Siuioe oiat ii I Sinnlai' lobbying by layperson organizations within Eu- R cc ive(l Januar y 26. 2019 Accepted March 27. 2009. rope has lead to the introduction of legislation t tt ban Corresponding author: liwchengcptirdue.edu hatterY cages oil 1. 2012 (CEC, 1998, 1999).

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1560 POIlLI: AND CIlLG In the United States, legislative actions attempt ing to 19 wk of age, the buds were randonmlv assigned into regulate poultry practices have been initiated in sev- 2 different housing treatments: batter y ('ages and fur- eral states (e.g., California, Illinois. and Washington). nished cages (n = 12/treatment). Based oil com- Similarly, several fast-food restaurant chains, including pany recommendations. 10 birds were housed per c'age. McDonalds. . and Kent itchy Fried Chicken. providing a stocking densit y of 610 cm 2 of floor space/ have acted by implementing written welfare guidelines bird. without counting nestbox and dmistbat lung areas that their egg suppliers are expected to adhere to. The (i.e.. 120 x 55 x 45 cm: length x width v height). The US poultry industry is in prime position to preempt furnished cages (FV 550-EU. Big Dutchtniami. Veclita. and influence any future legislation to bait or restrict Germany) had wire floors with solid metal walls and battery cages by evaluating and implementing more included perches arranged in front of time litter bath, a welfare-friendly housing systems for mnininiizing stress (lustbathuig area located at the left rear corner, scratch yet safeguarding bird well-being. pads behind time feed trough, and a nestbox area wit im Currently, researchers are examining various hous- a concealment curtain located at the right rear coiner. ing systems, such as deep-littered housing. aviaries. Sand was used as dustbathing substrate. The birds can floor pens, get-away cages, free-range, and furnished access the facilities without r€'strictioii. For ('onipari- cages and quantifying the effect oil welfare of birds son. attempts were mimade to use a. comparable stocking housed in those environments (Hansen. 1994: Cunning- density in the batter y cages. The battery cages were hamii and Mauldin, 1996; Dawkins et, al., 2004; Tauson, ('onmlnercial wire cages containing 6 birds, per cage. 2004: Hester, 2005: Mertens et al.. 2006). Among the providing 645 cni of floor space/bird (i.e.. 102 x 38 alternatives, furnished (also called enriched) cage sys- x 46 cm: length x width x height). Feed and water tems may offer a more suitable housing s steni for both were provided nil libit m mill to both treat nmeimts. Overhead improving well-being for birds and maintaining profile lights were 0mm a 16L:8D schedule, from 0700 to 2300 h. for producers (FAWC, 2007). Furitislied (ages attempt Both housing treatments were located within the same to provide enrichnient to birds while still taking advan- room at Purdue Universit y Poitit rv Farni. tage of the benefits of a small group size. The cages are Daily inspections were conducted by Poultr y Unit equipped with perches, (ilisthat lis. and nest big areas staff to observe for bodNr i ijurv kind inortalit. . The birds allowing the birds to meet the needs for their natu- were also inspected weekly for incidence of bmmmiiblefbot ral behaviors, such as nesting, roosting, and scratching and severe feather-pecking in) uries. The experimental (Lindberg and Nicol, 1997: Newberry. 1999; Cordiner protocols were approved by the Institutional A mnnial and Savory. 2000). Previous studies have shown that Care and Use Conmmmuit tee at Purdue Umnversitv. birds housed in the furnished cages also niiprove well- being by reducing fear. aggression, and Behavioral Observation Analysis and increasing bone mineral density (Gvaryahu et al., 1994: Newherrv, 1995; Kopka et al.. 2003). Although Video ('anieras were set up at the poultr y farm and furnished cage systems seem to he a possible way for ii- time bird behaviors were videotaped for ail light proving bird well-being, its influences have been shown period before blood collection at 30, .10 1 and 50 wk to be strain-, age-, and facility-dependent. Before rec- of age (blood samples were used for another analysis) ommending its widespread use within the egg industry. Behavioral observatiomis were conducted using time Nol- a full-scale scientific evaluation of its purposed benefits (Ills Observer software package (I\Iindware Technologies needs to be conducted, especially in \Vhite Leghorn Ltd.. Cahamnia, OH). The birds were observed at 5-nun birds. which are the major egg-producing birds in the intervals for the entire light period. At every5-mimi in- United States. terval. the number of hmirds in each area of the cage Behavioral changes in animals, including birds. have (cage floor, perch. dimstbathm, mmesthox), mmuniher of birds been used as reliable well-being indicmt ors iii evaluating in each body position (stand, sit, unable to see). and the capability of an animal to adapt to stimulations nuniber of birds performiniig each behavior (feed, drink, (Dawkins. 1999). The objective of this stud y was to walk. preening, exploratory pecking. and inactive) were determine the effects of furnished cages versus batter documiment.ed. All behavior ammal ysis was carried out by ('ages oil behavioral response to the environmnen- time sanie person experienced ill and ammalvz- tal stimulation,,, and to evaluate how these changes af- ing poultry behavior. fect bird well-being. Statistical Analysis MATERIALS AND METHODS Data were aimalyzed using a C LM in SAS Version Chickens and Housing Systems .0 (SAS Institute Inc.. Cary. NC). Model statements for data analysis included age, housing t.reatmneumt. and One hundred ninety-two i-d-old non-beak-timiiiied time interaction between age and treatment. Data were Thy-Line \V-36 White Leghorn chicks were neared using tested for mioruiahitv and corrected for miom'mmialit y if rice- standard ma.nagenmeul practices in raised wire cage. At essarv, dependent on individual data sets. Where sig-

RESEARCH NOTE 1561

Table 1. Rfu,tta of )lisiIlg ioitiIitiiitt. battery Cilges versus httlnslft'il cages, on frequency of postui'o slates in laying liens'

T3i t t('lV cage, Furijisiteil (agei.

30 iiL 40 ivk 50 wI, 30 k 10 \V k 50 wk

Stand 52.9 2.6" 51.9 k 4.9 85.8 ± 3.1 93.0 ± 2.9' 83.9 ± 3.9 sr,.s ± 3.8 Sit IT.! -L 2.6 15.5 + 4.9 14.3 + 3.4 6.2 2.9 ((.7 319 15.1 -1- 3.5 Posture transition index (;.!-) (1.9 5.3 ± ((.5 7.2 1- 1.1 1.5 ! 1,0" 6. 1) ILL' 710 .:. ((.5 cP ' t Signifieinit differejite lativeeli Ille lint )erv minI liiritt$a,d cage svi inc. "1p < 0.05: < 0.01 'Data are presented as mean + SE (a = 12). nificant. F-values were noted, appropriate post hoc tests furnished cages at 30 wk of age (Table 2. P < 0.001). In (turkeys) were performed to determine where these dif- battery cages. walking was gracluall reduced between ferences lay. A significant difference was at P < 0.0a. 30 to 50 wk of age (P < 0.05). whereas walking was lint changed ill the birds housed in furnished cages (P > 0.05). In contrast., the birds in furnished cages spent RESULTS illore t ilne feeding than those housed in bat t cry cages, Bird Health especially at 30 and 40 wk of age (P < 0.05 and 0.01. respect ivelv). One blvd housed ill battery cage died during the Drinking behavi(,)r was siginfictnitly affected by age, experiment. One bird housed in a furnished cage had with the birds housed in the furnished cages showing a. feedupact ion oil side of its beak, which was decreased time spent drinking at 40 wk of age (P < treated with Nolvosan (Fort Dodge Labs. Fort Dodge. 0.05). There was 110 significant difference by t rea.tnment IA) 11.11(1 lieale(l. Six birds housed iii furnished cages. (P > 0.05).At.50 wk of age, the level of preening be- but none in hatter ' y cages. had bin iblefoot. which was havior was higher in the birds housed in furnished cages treated with tripleantibiotic ointment and healed. No (P < (3.05). whereas the liens Ilolised ill cages feat-her pecking was seen durin g behavior observations. spent more time perfornung explorator y pecking (P < Therefore, no hens were found to be injured from feath- 0.05). (1 pecki i ig. Performance of dusthat.hi ig or sham (li.istbaI hung was not, observed in the birds housed either in furnished or Posture (Standing and Sitting) battery cages. En furnished cages. the birds performed exploratory pecking. resting. and preening behaviors ill There was no housing effect o il of standing the dust I )at hi area. or sitting except at 30 wkof age. At 30 wk of age, the Behavioral transition index, recorded as the number birds housed in the furnished cages spent more time of changes betweell behaviors, showed 110 significant. standing than those housed ill cages (Table 1. differences between housing treatments at 30 or 40 wk P < 0.05). Consistentl y, posture transition index (mc- of age (P > 0.05). however, the behavioral transition corded as the number of changes between i-attillg and index was significantl y increased from 40 to 50 wk of standing) was lower in the liens housed in the furnished age in the birds housed in the battery cages compared cages thaii those in the batter y cages (P < 0.05) wit'll t hn)se housed ill t he furnished("ages (P < 0.01).

Behaviors Furnishing Utilization The amnollilt of time spent walking showed a. treat- Perches, nest boxes. and (lust baths were provided only ment X age interaction. The birds housed ill to the birds hiotised ill the fun i isl led cages. 'Fl ie liens cages spent more tine walking than those housed in spent a. great anloulilt of time oil the perches (Figure 1),

Table 2. Effects of housing conditions, battery cages versus furnished cages. on various behaviors in having hens'

Battery ('ages Fm rim i,4 ed cage, tIe) ,mi' iii,' 30 a± 40 wk 50 icR 30 a k IL! c.1

Feed 25.4 ± 1.7" 16.5 ± 2:1.-I + 6.3'' 428 ± 5.8 35.1 ± 6.1" 3:1.7 ± 6.8 Drink 8.0 ± 1.8 7.7 + 3.11) 8.1 ± 2.1 12.7 ± 3.2" 4.3 ± 11.6' 8.6 ± 2.1" \Va.ik 2.1.7 ± 3.T" 15.6 ± 3.8 10.5 + 1.5' 5.(i ± I. 13.2 + 2.5 8.0 ± 2.7 Ireen 18.9 ± -Li 16.9 + 3.8 10.5 ± 2.2" 20.8± 6.9 13.1± 1.7 17.8 ± 2.1" l'xpI,'irator\' pecking 1.7 ± 1.3' 7.5 0.9'"± 2.2+ 1.5 1.5±0.5 2.2 ± 1.2" Bohm iii t r,u,si! iii, index :33.5 1 2.7 25.6 + . 12 102.8 ± 7.9" 29.7 ± 3.3 :39:3 3.! 55.5 ± 13.5'

'SigiI'icmumt ,.!ift'crei,ee weu ,vitl,iii time w,,,ii,, housing treatment (I' <' (1.05). " Sigriificmn,t dil'f,'re,ne se,ri la'tween Ilic battery and furnisla',1 mmm.gi' s,'s)i'i,,s "P (14)5: P 0(01). Data are presented as mean ± SE (it 12).

1562 1()HI,E AND (I-IEI\G Prelaving behavior a nd the pei'cei it age of eggs laid 40 in the nesth!)ox was not observed in this stud y because Co of its limitations of design. There is huge evidence that C 35 Co the nestbox is very important to birds during egg lay 30 -ing. Yue and Duncan (2003) reported that. c >iiipared •1- 25 with the birds provided with a nestbox, the birds with- D) 20 out a nestbox exhibited frustration behavior. stereo- Co 15 typed pacing. Cooper and Appleby (2003) indicated 4) 10 that birds are highly motivated to search a nesthox for E haying. Birds displayed a. great conservatisin in nest site 4- 5 selection during various preference tests (Bubier, 1996: 0 30 40 50 Cooper and Appleby, 2003: Zupan et al.. 2008). In furnished cages, time birds pei'fol'nied exploratory Weeks of age pecking. resting. and preening behaviors rather than

Figure 1. ihc purccutagoof [iwO sJ(clIl iitilizwg hI(ili[i(a of [lu ciustbatlnng in the. dust hat Ii area. These results were birds house in furnished cages. '1 here were no age effects on birds similar to the findings of Lindberg and Nicol (1997) and using perches (Perch), the tiesthox (NB). and dusthathing area (DR) those reported by Applehv et al. (2002). In these stud- (luring the observation time toad in the study. Data are presented as niean ± SE. ies, the birds performed foraging. resting. and standing alert behaviors in time clustbath rather than dustbathi- big behavior. Domestic: birds, such as \Vlnte Leghorn and the clustbath area was occupied approximately 5% W-36, have been highl y selected for egg production of the observation time. There were no significant. cif- in the battery caging systems (Hy-Line International. fererices in utilization of facilities among observed ages 2006). This may lead birds to adapt to the produc- (i.e.. 30. 40. and 50 wk of age: P> 0.05). tion environment with reduced dust hat lung behavior when compared -,vitli birds in natural environments. In a motivational stud y of dustbathing behavior. \\id- DISCUSSION owki and Duncan (2000) found that chickens were not willing to work harder when they were in a state of Furnishing Usage deprivation of ciusthath compared wit Ii those I hat had Perches, nestboxes, and dustbaths were utilized by recemitiv clustbathiecl. The findings were explained as an the birds throughout the first c ycle of lay. indicating opportunit y model of motivation. performing the be- that the birds may consider that the facilities are im- havior when the opportunity presented, rather than a portant, especially the perches. A similar finding was needs model of motivation. leaching to a state of suf- reported in several studies (Braastad. 1990; Appleby fering by the deprivation. V:iioiowski and Ilenisworthi et al., 1993). In those studies, birds spent 25 to 41%) (2008) also reported that birds dud not show frustration of the daytime on perches. However, birds are niore when substrate for tlustbathiiig was deprived. There- willing to spend time on perches at night. Appleby fore, increasin g space available by providing i-i (11151 bath (1998) reported that iiioi'e than 80% of birds perched area may increase performance of other comfortable at night. Iii another stud y, using modified conventional behaviors, such as pecking and preening, rather than battery cages with perches, Duncan et al. (1992) found tins! bat hing. In addition. dusthathing behavior could that up to 99% of birds perched during the night. The be affected by multiple factors. such as composition birds' utilization of perches could be an inherent be- anti amount of the dusthathing substrates (Moesta, et havior because birds use branches of trees for resting al., 2008). A well-designed study is needed to function- in nature. This hypothesis is supported by Hoppiti et ally and niotivationahlv analyze birds' natural behav- al. (2007). In these studies, the authors reported that iors, including dustbathiing behavior. bird response to facilitation is unlikely to be a social learning process. Bird well-being, at least in this por- Housing Environmental Effects tion, could be improved by providing perches to mccl on Bird Behavior their natural behavioral needs (Tloppitt et al., 2007). to utilize the extra space (Weeks and Nicol, 2006), or to Frequent d:hlddilgcs in behaviors. which were seen in avoid interactions with more aggressive bids (Appleby this experiment, have been shown to he indicative of and Hughes. 1991), or all three. In addition, the pro- restlessness, a stress indicator. in previous studies in vision of perches allows for mechanical loading of the humans and rodents (Koba et al., 2001: Schneider et birds' skeleton, which maintains their strength during al., 2006). Similarly, ,Johnson et al. (1998) reported that the lay cycle. In agreement with this hypothesis. No- cage-housed liens have been shown to have increased pka et al. (2003) reported that the birds housed iii fur- posture transitions over aviary-hiOtisedl liens. Similar to nished cages had better hone density than those housed those findings, at 50 wk of age. the births housed in bat- in battery cages. tery cages had significantly higher levels of behavioral

RESEARCH NOTE 1563 transit ions than thosethose housed in furnisher! cages (Table comfort behaviors and associated changes iii stress-as- 2). In addition, at 30 wk of age. the birds housed in sociated neuroliorn 101 tes. furnished ('ages showed significantly more time spent staiidiiin whereas the birds housed in batter y ('ages were shown to spend iiioi'e time sitting on the ('age floor ACKNOWLEDGMENTS (Table I). Siniilni' 10 the current results. turkeys housed ill furnished cages had iiicreased latenc y to sit when \Ve I hank Fred Ilanm and the stall at the Purdue compared with ones housed without furnishings. This Poultr y Facility as well as the technicians at the Live- increased latency to sit may indicate better muscular- stock Behavior Research Unit of the USDA in West skeletal function (Maxwell. 1993). In the current study. Lafayette for their outstanding assistance. We also provision of perches may also have benefited birds thank Big Dutchman Company for providing furnished housed in furnished cages skeletallv and hehaviorahl. cages. therefore altering their behaviors. Previous studies have shown that housing environ- REFERENCES ments affect birds eating behavior, .JolinsOl) ci al.

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15(34 POHLE AND CIIENG

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