Mys et l. Journl of Animl Siene nd Biotehnology 213, 4:2 http://www.jssi.om/ontent/4/1/2 JOURNAL OF ANIMAL SCIENCE AND BIOTECHNOLOGY RESEARCH Forge nd reed effets on ehvior nd temperment of pregnnt eef heifers Angel R Mys 1, Mihel L Looper 1, Benjmin C Willimson 1,4, Kenneth P Coffey 1, Wyne K Colentz 2, Glen E Aiken 3 nd Chrles F Rosenkrns Jr 1* Open Aess Astrt Bkground: Integrtion of ehviorl oservtions with trditionl seletion shemes my led to enhned niml well-eing nd more profitle forge-sed ttle prodution systems. Brhmn-influened (BR; n = 64) nd Gelvieh Angus (GA; n = 64) heifers onsumed either toxi endophyte-infeted tll fesue (E+) or one of two nontoxi endophyte-infeted tll fesue (NT) ultivrs during two yr. Heifers were weighed t midpoint nd termintion of grzing. Grzing ehvior (grzing, resting in the shde, lying, or stnding without grzing) ws reorded (n = 13 visul oservtions per yr in June nd July) for eh psture. During yr 2, exit veloity (EV) nd serum proltin (PRL) were determined. Results: Grzing ehvior ws influened (P <.5) y n intertion etween fesue ultivr nd reed type. Gelvieh Angus heifers ssigned to E+ pstures hd the lowest perentge of nimls grzing nd the lrgest perentge of nimls resting in the shde. Brhmn-influened heifers hd fster EV (P <.1) thn GA heifers (.52 vs..74 ±.4 s/m, respetively). Body weight (BW) ws ffeted (P <.1) y n intertion of tll fesue ultivr nd d, nd n intertion of tll fesue ultivr nd reed type. Heifers grzing NT pstures were hevier (P <.1) thn heifers grzing E+ pstures t midpoint nd termintion. Gelvieh Angus heifers grzing NT pstures were hevier (P <.1) thn GA nd BR heifers grzing E+ nd BR heifers grzing NT pstures. An intertion of forge ultivr nd reed type ourred on serum PRL (P <.1). Conlusion: Colletively fesue ultivr, EV, nd onentrtions of serum PRL were ssoited with grzing ehvior. Heifers grzing NT pstures were oserved to e grzing more thn heifers ssigned to E+ pstures, regrdless of reed type, whih my hve ontriuted to hnges in BW nd verge dily gin (ADG) in heifers. Integrtion of ehviorl oservtions long with trditionl seletion shemes my led to enhned niml well-eing nd more profitle forge-sed ttle prodution systems. Keywords: Cttle, Endophyte-infeted tll fesue, Grzing ehvior, Proltin, Temperment Bkground Tll fesue [Lolium rundineum (Shre.) Drysh.] is highly dptive grss speies with over 16 million h found in the southern nd estern regions of the USA [1]. Ergot lkloids, suh s ergovline, re produed y n endophyti fungus (Neotyphodium oenophilum) tht infets tll fesue plnts [2]. Consumption of E+ leds to fesue toxiosis, whih is hrterized y redued feed intke nd ADG, elevted ody temperture, inresed respirtion rte, nd poor oneption rtes * Correspondene: rosenkr@urk.edu 1 Deprtment of Animl Siene, University of Arknss, Fyetteville, AR 7271, USA Full list of uthor informtion is ville t the end of the rtile [3-6]. Helth issues ssoited with E+ re estimted to ost livestok produers over $1 illion nnully [7]. Cttle response to E+ onsumption hs een relted to reed omposition with Brhmn-influened ttle eing more tolernt of ergot lkloids, resulting in improved weight gin nd reprodutive suess while grzing E+ when ompred to British reeds of ttle [8-1]. Tll fesue ultivrs infeted with nontoxi novel endophytes do not produe ergot lkloids nd led to fster livestok gins ompred to niml gins when grzing E+ [6,11]. Cultivrs of NT hve plnt persistene similr to E+ with niml performne equivlent to endophytefree tll fesue [12]. While niml performne of ttle grzing E+ nd NT is well doumented, it is unknown if 213 Mys et l.; liensee BioMed Centrl Ltd. This is n Open Aess rtile distriuted under the terms of the Cretive Commons Attriution Liense (http://retiveommons.org/lienses/y/2.), whih permits unrestrited use, distriution, nd reprodution in ny medium, provided the originl work is properly ited.
Mys et l. Journl of Animl Siene nd Biotehnology 213, 4:2 Pge 2 of 5 http://www.jssi.om/ontent/4/1/2 differentil niml response is due to physiologil responses or ehviorl nd temperment hnges. Cttle with exitle temperments exhiit redued weight gin, nd milk prodution [13,14]. Therefore, our ojetive ws to evlute the effets of tll fesue ultivr nd reed type on weight gin, ehvior, temperment, nd onentrtions of serum proltin (PRL) of pregnnt eef heifers. Methods Experimentl design Reserh ws onduted t USDA-Agriulture Reserh Servie, Dle Bumpers Smll Frms Reserh Center, Booneville, Arknss, USA (35 9 N, 93 17 W). Animl proedures used for this 2-yr study were pproved y the USDA-Agriulture Reserh Servie niml welfre ommittee. Tretments were rrnged s 2 3 ftoril with min effets of reed nd tll fesue ultivr. Heifers (18 ± 2 mo of ge) were either Brhmn-influened (1/8 to 1/3 Bos indius; BR) or Gelvieh Angus (GA). Tll fesue ultivrs were E+, nd nontoxi [Jesup infeted with strin AR542 endophyte (MQ; 13), or HiMg with strin 4 endophyte (HM; 6)]. Yer 1 onsisted of 72 heifers (36 of eh reed) grzing from 28 Mrh until 5 July. During yr 2, 56 heifers (28 of eh reed) egn grzing 29 Mrh nd ontinued until 18 July. On d of oth yr, heifers were weighed nd rndomly ssigned within reed type to grze tll fesue pstures (4 heifers/h). Yer 1 onsisted of six pstures per fesue ultivr while yr 2 onsisted of four pstures of E+, five pstures of HM nd five pstures of MQ. Stoking rte ws four heifers per hetre (2 heifers per reed). All pstures were estlished >3yr nd were >85% fesue; pstures were not llowed to go to seed. Wter ws provided d liitum, forge ws not limited during the study, nd shde ws ville for ll nimls. Heifers were weighed on d 56 (midpoint) nd 99 (termintion of grzing) in yr 1, nd on d 6 (midpoint) nd 116 (termintion of grzing) during yr 2. To ssess toxiity of fesue pstures, rndom forge smples (8 to 1 smples per h) were olleted monthly from eh psture, pooled within psture, ut into 5.1-m piees, nd stored t 4 C until ergovline onentrtions were determined using highperformne liquid hromtogrphy [15]. Behvior dt Grzing ehvior ws visully reorded in yr 1 nd 2 etween 13: nd 15:3 h on 13 dtes, in individul pstures, during the months of June nd July (n = 13 visul oservtions). Within yr, eh heifer (n = 4 heifers per psture) ws oserved visully y the sme tehniins t distne of 75 to 1 m for pproximtely 2 min. Heifer ehvior ws lssified into one of four tegories (grzing, resting in shde, lying, or stnding without grzing). During yr 2, hute exit veloity (EV), n inditor of niml temperment, ws determined on d, 6, nd 116 using two infrred sensors (FrmTek In., North Wiley, Texs, USA). Heifers were gthered with ll-terrin four-wheeled vehiles on eh dt olletion dy y the sme personnel nd wlked from individul pstures 35 to 1,24 m to individul holding pens; heifers remined in their individul psture group during the hndling proess. Heifers were moved from pens to urved working lley (.8 m wide nd 7.9 m in length) with solid sides. Body weight ws reorded nd lood smple olleted while eh heifer ws restrined in the hydruli hndling hute (Filson Livestok Equipment, Protetion, Knss, USA). As heifers exited the hndling hute nd trversed 1.8 m, EV (s/m) ws reorded [16]. Mximum mient dily temperture nd mximum dily reltive humidity (%) during visul oservtion of grzing ehvior were reorded using wether sttion (model 9, Spetrum Tehnologies In., Plinfield, Illinois, USA) loted 5 km from the tll fesue pstures. Blood olletion nd hormone nlysis In yr 2, lood smples were otined y venipunture of the medin udl vein into vuum tues (Beton, Dikinson, Frnklin Lkes, New Jersey, USA) on d, 6, nd 116. Blood smples were llowed to lot for 24 h t 4 C nd entrifuged (1,5 g for 25 min). Serum ws stored t 4 C until PRL onentrtions were nlyzed y rdioimmunossy [17], with intr-ssy oeffiient of vrition (CV) of 11% nd inter-ssy CV of 15%. Sttistil nlysis Weight gin nd ehviorl vriles did not differ (P >.1) etween heifers onsuming the two NT ultivrs (HM or MQ); therefore, mens nd perentges for NT tretments were pooled. Body weight, ADG, PRL, nd EV dt were nlyzed using mixed model proedures of SAS (SAS Inst., In., Cry NC) with psture s the experimentl unit. Model ssumed ompletely rndomized lok design with psture s experimentl unit. Fesue ultivr nd reed type were replited within yr nd ross yr. Fixed effets of fesue ultivr (E+ vs. NT), reed type (BR vs. GA), nd intertions were ompred using F-test proteted t-tests (P <.5). Fesue ultivr, reed type, nd intertive effets on oserved grzing ehvior were nlyzed y Chi-squre. Results Forge nd environmentl onditions Conentrtions of ergovline rnged from.25 to.87 mg/kg of dry mtter (pooled SD =.3) for E+ tll fesue pstures from April to mid-july; overll men ergovline ws.55 ±.2 mg/kg of dry mtter. Forge smples were pooled prior to determintion of ergovline. Without
Mys et l. Journl of Animl Siene nd Biotehnology 213, 4:2 Pge 3 of 5 http://www.jssi.om/ontent/4/1/2 replited vlues, sttistil nlysis on onentrtion of ergovline in E+ tll fesue pstures ws not onduted. No detetle ergovline ws found in NT pstures. On dy when ehvior ws oserved, mximum mient dily temperture verged 31.1 ± 2.6 C nd men mximum reltive humidity ws 98.2 ± 3.7%. Grzing ehvior Grzing ehvior etween 13: nd 15:3 h ws influened (P <.5) y n intertion etween fesue ultivr nd reed type (Figure 1). Gelvieh Angus heifers ssigned to E+ pstures hd the lowest (P <.5) perentge of nimls lssified s grzing nd the lrgest (P <.5) perentge of nimls resting in the shde. In ontrst, heifers ssigned to NT pstures hd the lrgest perentge of nimls lssified s grzing nd BR heifers ssigned to NT pstures hd the lowest perentge resting in the shde. Proltin onentrtions Serum PRL onentrtions were ffeted (P <.5) y n intertion of fesue ultivr nd reed type (Figure 2). Brhmn-influened heifers grzing NT pstures hd greter (P <.5) PRL onentrtions thn GA heifers grzing NT pstures (233.2 ± 16.5 vs. 125.2 ± 16.5 ng/ml), nd BR nd GA heifers grzing E+ hd the lowest (3.8 ± 26 nd 13.5 ± 2 ng/ml; P <.5) onentrtions of PRL. Exit veloity Brhmn-influened heifers trversed the 1.8 m distne fster (P <.1) thn GA heifers (.52 vs..74 ±.4 s/m, respetively). Exit veloity lso ws influened y d of olletion (P <.2) with EV on d not different (P >.6) thn EV on d 6 or d 116 (.61,.54, nd.73 ±.5 s/m, respetively). However, EV on d 6 ws Proltin, ng/ml 25 2 15 1 5 GA Breed Type fster (P <.1) thn EV on d 116. Forge ultivr did not influene (P >.1) exit veloity throughout the study. Body weight nd verge dily gin Body weight ws ffeted (P <.1) y n intertion of fesue ultivr nd dy of olletion, nd n intertion of fesue ultivr nd reed type. Body weights t the initition of grzing were not different (47 vs. 45 ± 5 kg; P >.1) mong heifers ssigned to E+ nd NT pstures. Heifers grzing NT pstures were hevier (P <.1) thn heifers grzing E+ pstures t midpoint (58 ± 3 d) nd termintion (18 ± 12 d) of grzing (Figure 3). Gelvieh Angus heifers grzing NT pstures were hevier (P <.1) thn GA nd BR heifers grzing E+ nd BR heifers grzing NT pstures (Figure 4). Heifer ADG ws lulted for eh period (first period = d to midpoint; seond period = midpoint to termintion) of the study nd overll ADG. During the first period (58 ± 3 d), heifer rte of gin ws fster (P <.1) on NT pstures when ompred with heifers BR Figure 2 Intertion of forge ultivr nd reed type on serum proltin of eef heifers; P<.5; pooled SE = 21.25. Perentge 8 7 6 5 4 3 2 1 BR-NT BR-E+ GA-NT GA-E+ d Grzing Shde Lying Stnding Behvior Figure 1 Intertion of forge ultivr nd reed type on grzing ehvior of eef heifers; d P<.5. Weight, kg 6 5 4 3 2 1 e e d 58 18 Dy on Tril Figure 3 Intertion of forge ultivr nd dy on ody weight of eef heifers; de P<.1; pooled SE = 4.9.
Mys et l. Journl of Animl Siene nd Biotehnology 213, 4:2 Pge 4 of 5 http://www.jssi.om/ontent/4/1/2 Weight, kg 6 5 4 3 2 1 BR Breed Type grzing E+ pstures (1.1 vs..6 ±.4 kg). Gelvieh Angus heifers hd fster rte of gin (P <.1) thn BR heifers (.96 vs..8 ±.4 kg). In ontrst, ADG during the seond period (5 ± 9 d) ws not ffeted (P >.11) y fesue ultivr, reed type, or their intertion. During the 18 ± 12 d study, overll heifer ADG ws ffeted y reed type nd fesue ultivr. Rte of gin y GA heifers ws fster (P <.2) thn tht of BR heifers (.77 vs..69 ±.3 kg). Heifers grzing NT pstures exhiited greter (P <.1) ADG thn heifers grzing E+ pstures (.87 vs..6 ±.3 kg). Disussion Fesue toxiosis is ondition tht ours in livestok nd n lter grzing ehvior [18,19]. Ergovline is the primry ergopeptine found in E+ tll fesue, whih leds to physiologil hnges nd results in fesue toxiity [2,21]. Our E+ pstures hd ergovline onentrtions (.55 mg/kg of dry mtter) during June nd July tht were similr to pulished vlues of ergovline ple of induing fesue toxiosis in ttle nd sheep [22,23]. Dietry onentrtions of ergovline etween.4 nd.75 mg/kg DM hve een reported to use fesue toxiosis in ttle [24]. Pregnnt heifers hve n elevted ody metolism nd fsting het prodution [25]. Tht inresed demnd for ody temperture regultion oupled with the stress ssoited with E+ led us to study reed type nd fesue ultivr on grzing ehvior of pregnnt eef heifers. We oserved tht GA heifers ssigned to E+ pstures hd lower perentge of heifers grzing during middy ompred with BR heifers grzing E+ pstures. Heifers grzing MQ nd HM nontoxi endophyte-infeted pstures, in the urrent study, were oserved to e grzing more thn heifers ssigned to E+ pstures, regrdless of reed type. In previous study steers spent more time GA Figure 4 Intertion of forge ultivr nd reed type on ody weight of eef heifers; P<.5; pooled SE = 4.. grzing endophyte-free tll fesue ompred with E+, nd steers onsuming E+ were more sensitive to solr rdition [26]. Cttle onsuming E+ typilly hve redued PRL onentrtions [5,7]. Heifers grzing E+ hd redued PRL onentrtions s ompred to heifers grzing NT pstures in the present study, nd PRL onentrtions of heifers on E+ were not influened y reed type. The BR heifers grzing NT pstures hd the gretest perentge of nimls grzing nd inresed PRL onentrtions; those findings support the possile onnetion etween PRL nd niml ehvior. Inresed tivity, whih ours during grzing, ws ssoited with inresed PRL onentrtions [27]. The mehnism desriing the physiologil nd ehviorl reltionship etween tivity nd PRL onentrtions is not yet fully understood. In this study, temperment of heifers my hve ontriuted to hnges in BW nd ADG. Cttle hd fster EV times t the initition of grzing ut EV times slowed s the study progressed. These dt support previously reported reserh in whih temperment of nimls improved over time, presumly due to dpttion of repeted hndling [16]. Gelvieh Angus heifers hd slower EV times suggesting etter temperments reltive to BR heifers, whih is onsistent with previous work reporting more doile tempered nimls hd greter BW nd ADG [13,28]. Conlusions Colletively fesue ultivr, EV, nd serum PRL onentrtions were ssoited with grzing ehvior, whih my ontriute to hnges in BW nd ADG. Integrtion of ehviorl oservtions long with trditionl seletion shemes my led to enhned niml well-eing nd more profitle forge-sed ttle prodution systems. Arevitions BR: Brhmn-influened; GA: Gelvieh Angus; E+: Toxi endophyte-infeted tll fesue; NT: Nontoxi endophyte-infeted tll fesue; PRL: Proltin; ADG: Averge dily gin; EV: Exit veloity; CV: Coeffiient of vrition. Competing interests The uthors delre tht they hve no ompeting interests. Authors ontriutions MLL oneived the study nd experimentl design. ARM, CFR, nd MLL rried out the sttistil nlysis nd drfting of mnusript. BCW ompiled dt nd revised initil drft mnusript. KPC nd WKC supplied the experimentl nimls nd revised mnusript. GEA estlished nd mnged pstures used in study. All uthors red nd pproved the finl mnusript. Aknowledgements The uthors grtefully knowledge S. Tler nd B. Woolley (USDA-Agriulturl Reserh Servie, Booneville, AR) for tehnil ssistne nd dily niml mngement; D. Burner (USDA-Agriulturl Reserh Servie) for limti dt; nd G. Rottinghus nd C. Roerts (University of Missouri) for ergovline nlyses.
Mys et l. Journl of Animl Siene nd Biotehnology 213, 4:2 Pge 5 of 5 http://www.jssi.om/ontent/4/1/2 Author detils 1 Deprtment of Animl Siene, University of Arknss, Fyetteville, AR 7271, USA. 2 USDA-ARS, US Diry Forge Reserh Center, Mrshfield, WI 54449, USA. 3 USDA-ARS, Forge Animl Prodution Reserh Unit, Lexington, KY 4546, USA. 4 Deprtment of Agriulturl Sienes, Morehed Stte University, 327 Reed Hll, Morehed, KY 4351, USA. Reeived: 15 Mrh 213 Aepted: 23 My 213 Pulished: 28 My 213 Referenes 1. Hovelnd CS, MCnn MA, Hill NS: Rottionl vs. ontinuous stoking of eef ows nd lves on mixed endophyte-free tll fesueermudgrss psture. J Prod Agri 1997, 1:245 25. 2. Morgn-Jones G, Gms W: Notes on Hyphomyetes, XLI. An endophyte of Festu rundine nd the nmorph of Epihloe typhin, new tx in one of two new setions of Aremonium. Myotxon 1982, 15:311 318. 3. Browning R Jr: Effets of endophyte-infeted tll fesue on inditors of therml sttus nd growth in Hereford nd Senepol steers. J Anim Si 24, 82:634 643. 4. 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Brown MA, Brown AH Jr, Jkson WG, Miesner JR: Genotype environment intertions in Angus, Brhmn, nd reiprol ross ows nd their lves grzing ommon ermudgrss nd endophyte-infeted tll fesue pstures. J Anim Si 1997, 75:92 925. 9. Brown MA, Threl LM, Brown AH Jr, Jkson WG, Miesner JR: Milk prodution in Brhmn nd Angus ows on endophyte-infeted fesue nd ommon ermudgrss. J Anim Si 1993, 71:1117 1122. 1. Looper ML, Rorie RW, Person CN, Lester TD, Hllford DM, Aiken GE, Roerts CA, Rottinghus GE, Rosenkrns CF Jr: Influene of toxi endophyteinfeted fesue on sperm hrteristis nd endorine ftors in yerling Brhmn-influened ulls. J Anim Si 29, 87:1184 1191. 11. Bouton JH, Lth GCM, Hill NS, Hovelnd CS, MCnn MA, Wtson RH, Prish JA, Hwkins LL, Thompson FN: Reinfetion of tll fesue ultivrs with nonergot lkloid-produing endophytes. Agron J 22, 94:567 574. 12. Gunter SA, Bek PA: Novel endophyte-infeted tll fesue for growing eef ttle. J Anim Si 24, 82:E75 82. 13. Voisinet BD, Grndin T, Ttum JD, Connor SFO, Struthers JJ: Feedlot ttle with lm temperments hve higher verge dily gin thn ttle with exitle temperments. J Anim Si 1997, 75:892 896. 14. Breuer K, Hemsworth PH, Brnett JL, Mtthews LR, Colemn GJ: Behviorl response to humns nd the produtivity of ommeril diry ows. Appl Anim Behv Si 2, 66:273 288. 15. Hill NS, Rottinghus GE, Agee CS, Shultz LM: Simplified smple preprtion for HPLC nlysis nd ergovline in tll fesue. Crop Si 1993, 33:331 333. 16. Curley KO Jr, Pshl JC, Welsh TH Jr, Rndel RD: Tehnil note: Exit veloity s mesure of ttle temperment is repetle nd ssoited with serum onentrtion of ortisol in Brhmn ulls. J Anim Si 26, 84:31 311. 17. Bernrd JK, Chestnut AB, Erikson BH, Kelly FN: Effets of preprtum onsumption of endophyte-infeted tll fesue on serum proltin nd susequent milk prodution. J Diry Si 1993, 76:1928 1933. 18. Semn DH, Stuedemnn JA, Hill NS: Behvior of steers grzing monoultures nd inry mixtures of tll fesue. J Anim Si 1999, 77:142 1411. 19. Coffey KP, Moyer JL, Brzle FK, Loms LW: Amount nd diurnl distriution of grzing time y stoker ttle under different tll fesue mngement strtegies. Appl Anim Behv Si 1992, 33:121 135. 2. Lyons PC, Plttner RD, Bon CW: Ourrene of peptide nd lvinet ergot lkloids in tll fesue. Siene 1986, 232:487 489. 21. Porter JK: Anlysis of endophyte toxins: Fesue nd other grsses toxi to livestok. J Anim Si 1995, 73:871 88. 22. Aiken GE, Looper ML, Tler SF, Bruer DK, Striklnd JR, Shrik FN: Influene of stoking rte nd steroidl implnts on growth rte of steers grzing toxi tll fesue nd susequent physiologil responses. J Anim Si 26, 84:1626 1632. 23. Gderry MS, Denrd TM, Spiers DE, Piper EL: Effets of feeding ergovline on lm performne in het stress environment. J Anim Si 23, 81:1538 1545. 24. Tor-Agidye J, Blythe LL, Crig AM: Correltion of endophyte toxins (ergovline nd lolitrem B) with linil disese: Fesue foot nd perennil ryegrss stggers. Vet Humn Toxiol 21, 43:14 146. 25. Ferrell CL, Grret WN, Hinm N, Grihting G: Energy utiliztion y pregnnt nd non-pregnnt heifers. J Anim Si 1976, 42:937 95. 26. Semn DH, Stuedemnn JA, Anderson JE: Spetrl nlysis of ovine grzing ehvior on Neotyphodium oenophilum infested tll fesue. Appl Anim Behv Si 1997, 54:73 87. 27. Yyou K, It S, Ymmot N, Kitgw S, Okmur H: Reltionships of stress responses with plsm oxytoin nd proltin in heifer lves. Physiol Behv 21, 99:362 369. 28. Burrow HM: Mesurements of temperment nd their reltionships with performne trits of eef ttle. Anim Breed Astr 1997, 65:477 495. doi:1.1186/249-1891-4-2 Cite this rtile s: Mys et l.: Forge nd reed effets on ehvior nd temperment of pregnnt eef heifers. Journl of Animl Siene nd Biotehnology 213 4:2. Sumit your next mnusript to BioMed Centrl nd tke full dvntge of: Convenient online sumission Thorough peer review No spe onstrints or olor figure hrges Immedite pulition on eptne Inlusion in PuMed, CAS, Sopus nd Google Sholr Reserh whih is freely ville for redistriution Sumit your mnusript t www.iomedentrl.om/sumit