The effect of different selenium sources during the finishing phase on beef quality

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1 Journl of niml nd Feed Sciences, 24, 2015, The Kielnowski Institute of niml Physiology nd Nutrition, PS, Jłonn The effect of different selenium sources during the finishing phse on eef qulity C.. Sgoifo Rossi 1,4, R. Compini 1, G. ldi 1, C.E.M. ernrdi 1, M. Murro 2, J.-P. Mrden 3 nd V. Dell Orto 1 1 University of Miln, Deprtment of Helth, niml Science nd Food Sfety, Vi G. Celori 10, 20133, Miln, Itly 2 Consorzio grrio Lomrdo Veneto, Vi Frnci 2, 37135, Veron, Itly 3 Lesffre Feed dditives, 137 rue Griel Péri, Mrcq-en-rœul, Frnce KEY WORDS: eef heifers, eef qulity, eef shelf-life, met colour, selenium, yest Received: 11 ugust 2014 Revised: 3 June 2015 ccepted: 15 June Corresponding uthor: e-mil: crlo.sgoifo@unimi.it STRCT. Selenium (Se) is involved in severl iologicl functions nd its supplementtion is necessry for frm nimls. Se cn e provided in orgnic or inorgnic forms, which re metolized differently. The im of this study ws to compre the effects of switching the Se source in the lst 60 dys of fttening on eef qulity nd Se content in met. Chrolise eef heifers supplemented since the eginning of the fttening period with sodium selenite (162 heds; 517 ± 61 dys of ge) were divided into two groups, fed the sme diet, in which Se (0.2 mg Se kg 1 DM of feed) ws provided s sodium selenite (; 82 heds, ± 33.7 kg ody weight W) or selenium-enriched yest (; 80 heds, ± 41.7 kg W). The Se source did not ffect growth performnce, met centesiml composition, thwing loss, cooking or drip losses, nd ph during 8 dys of eroic storge. supplementtion improved the met Se content (P < 0.001) nd tended to reduce sher force (P = 0.076) t 48 h post mortem. Lightness (P < 0.01) nd yellowness (P < 0.01) decresed with the durtion of storge nd were higher in the group compred with the group during 8 dys of storge. Met from group lso showed etter visul score for colour (P < 0.01), odour (P < 0.05), surfce wetness (P < 0.05) nd overll ppernce (P < 0.01). Under the given experimentl conditions, switching eef heifers from inorgnic to orgnic Se in the lst two months of fttening improved met tenderness, shelf life, colour stility nd muscle Se content. Introduction Selenium (Se), in form of selenocysteine, is present t the ctive site of glutthione peroxidse, thioredoxin reductse, iodothyronine deiodinse, seleno-phosphte synthetse 2, selenoprotein P, nd different kinds of selenoproteins, nd is, therefore, involved in the reduction of oxidized ntioxidnts, scvenging rective oxygen species, synthesis of thyroid hormones, protection of DN nd proteins from oxidtion, redox signls, nd immune responses (Lu nd Holmgren, 2009). Thnks to these iologicl roles, Se supplementtion improves ruminnts immune response, neutrophil nd lymphocyte

2 94 Sodium selenite or selenium-enriched yest eef qulity ctivity nd disese resistnce (Finch nd Turner, 1996; Spers, 2000; Chuhn et l., 2014). These results, coupled with the soil deficiency of Se in lrge res of the world (Gissel-Nielsen, 1987; Cntor, 1997; McDowell, 1997; Oldfield, 2002), underline the need to dminister supplementry Se to frm nimls. Dietry Se cn e supplemented through inorgnic or orgnic forms. The first re minly represented y minerl slts such s selenite or selente of sodium or colt, while, the ltter, y selenium-enriched yest (), in which the min selenocompund is represented y selenomethionine (SeMet), or SeMet itself (minly produced from selenium enriched yests; Korhol et l., 1986). Due to different metolism, inorgnic forms re chrcterized y lower iovilility thn orgnic forms (Weiss, 2005). In terms of eef nd vel qulity nd oxidtive stility, lthough orgnic supplementtion generlly incresed the met Se content compred with inorgnic supplements t the sme dosge (Juniper et l., 2008; Cozzi et l., 2011; Richrds et l., 2011), inconsistencies in the effects on met qulity hve een reported. Despite long-term orgnic Se supplementtion cn significntly increses dietry costs, only Cozzi et l. (2011) hve studied short-term supplementtion in ullocks. Thnks to the higher iovilility of orgnic Se, we hypothesize tht short-term supplementtion my e le to improve met qulity nd Se content, with miniml impct on production cost. In the present study, short-term supplementtion strtegy hs een tested on eef heifers, chosen ecuse they nowdys lredy represent premium product t the retil level, nd re, therefore, more suitle for high-se eef production compred with ullocks. Mteril nd methods nimls nd niml cre The study ws performed in commercil intensive eef fttening frm locted in the northest of Itly. totl of 162 Chrolise heifers, of verge ge of 517 ± 61 dys, were enrolled nd rndomly ssigned to the two dietry tretments: sodium selenite () or selenium-enriched yest (). nimls were housed in two lrge open-ir yrds, one per tretment, with full concrete floor covered with mize stoves. The tril ws conducted during the lst 60 dys prior to slughter. The group included 82 heds with n verge ody weight (W) of ± 33.7 kg, while the group included 80 heds with verge W of ± 41.7 kg. niml cre nd tretment were in ccordnce with the Europen Community 1986 guidelines No Experimentl diets nd feeding routine The heifers were fed the sme sl diet (%: mize silge 43.3, ryegrss silge 14.4, high moisture mize 19.3, whet rn 7.2, mize gluten feed dry 4.8, nd protein-firous mix 11.0) contining s fed, %: crude protein 26.2, ether extrct 4.5, crude fire 10.5, sh 13.8, UI kg 1 : vitmin , mg kg 1 : vitmin D , vitmin E 120.0, vitmin 1 2.4, vitmin H 1.6, nicin 400.0, Co 0.8, Mn 120.0, Se 3.2, Zn 200.0, Fe 85.5, I 4.0, ure 24.5, formulted to meet or exceed NRC nutritionl requirements (NRC, 2000), differing only in selenium source: or (Selsf EC No ), produced y Scchromyces cerevisie (strin CNCM-I3399, Lesffre Feed dditives Itli, Itly), in which inorgnic Se ccounted for less thn 1% of the totl Se. Orgnic selenocompounds were minly represented y selenomethionine (62.7%) nd selenocysteine (2% to 4% of totl Se), while the remining orgnic Se compounds were not specified (EFS, 2009). Se ws supplemented through the minerl nd vitmin mix, nd its inclusion ws trgeted to provide 0.2 mg Se kg 1 DM of feed. Experimentl diets were dministered d liitum nd delivered in totl mixture rtio (TMR) form once dy in the morning y feed mixer wgon, provided with lnce to weigh the inclusion of ech ingredient. Wter ws ville d liitum. Growth performnce nd helth sttus Individul weight ws recorded prior to the morning feeding on enrolment (dy 0) nd the dy efore slughter (dy 60) nd verge dily gin (DG) ws susequently clculted. Helth sttus ws monitored dily y the veterinrin stff nd no dverse clinicl symptom ws recorded. Met smples nd nlysis t the end of the finishing period, the nimls were slughtered t the sme slughterhouse nd crcss chrcteristics were recorded. fter slughtering, conformtion (SEUROP) nd fttening score (1 5) were ssessed y n expert judge following EU legisltion (Council Regultion (EEC) No. 1026/91). Cold crcss weight ws otined fter 48 h of chilling t temperture of 0 C to 4 C nd, t the sme time, smples of the longissimus thorcis muscle etween the 5 th nd the 7 th ri were tken from 30 homogenous crcsses for the experimentl group. Ech smple ws divided into three susmples, two 2.50 cm steks, used fresh, the first one to evlute met colour, ph, wter holding

3 C.. Sgoifo Rossi et l. 95 cpcity (WHC), nd the second for shelf-life ssessment, dily for 8 consecutive dys. The third susmple ws weighed, vcuum-pckged, nd kept frozen t 20 C until chemicl nd physicl nlysis. The shelf-life of ech stek, kept in plstic ox, overwrpped with polyethylene film nd kept t 0 C to 4 C in drk room, ws visully ssessed dily y three-memer expert food inspector pnel, which evluted len colour (8 right cherry-red, 1 extremely drk rown or green/grey), overll ppernce (8 extremely desirle, 1 extremely undesirle), surfce wetness (7 humid nd right; 4 dry), nd odour (7 fresh eef odour; 5 no odour; 3 slight odour development ut still cceptle; 2 definite off-odour indictive of spoiled eef; 1 very strong off-odour ssocited with spoiled eef); the verge of the three oservtions ws considered for sttisticl nlysis. On the other smple, kept under the sme conditions, ph nd instrumentl colour were recorded dily, while drip-loss ws ssessed t the eginning nd t the end of storge. Mesurements of ph were mde y portle ph-meter (HI 98150, HNN Instruments Inc., Woonsocket, RI, US) equipped with glss electrode (3 mm Ø conic tip) suitle for met penetrtion; vlues for ech smple cme from the verge of three mesurements. Colour determintion ws performed using CR310 Chrommeter, set on D65 illuminnce, view ngle 10, clirted on the CIEL colour spce system using white clirtion plte (Clirtion Plte CR-43, Minolt Cmers) nd lightness (L*), redness (*), nd yellowness (*), were clculted ccording to the CIEL system. The colorimeter hd n 8-mm mesuring re nd the verge of 10 repetitions ws recorded s the vlue for ech smple. For drip loss determintion, smples were dried from superficil wetness nd weighed t the strt nd t the end of storge time. Chemicl composition (dry mtter, ether extrct, crude protein nd sh) ws determined on smples trimmed from externl ft nd connective tissue nd homogenized for 30 sec ccording to OC (1990). Thwing loss ws ssessed y weighing, freezing, nd weighing fter 24 h of thwing t 4 C. Cooking loss ws determined, s descried y Honikel (1998), s the weight lost fter cooking in wter th until the core temperture reched 75 C (monitored with temperture meter HI98840, HNN Instruments Inc., Woonsocket, RI, US) nd 24 h of storge t 4 C. efore eing weighed, the smples were lotted dry. The difference etween pre- nd post-cooking weights ws used to clculte the percentge loss during cooking. fter cooking loss determintion, six cylindricl cores, 1.27 cm in dimeter, prllel to fire orienttion, were otined nd used for sher force evlution, using Wrner-rtzler sher force texture nlyser (model 4466; Instron Corp., Cnton, M, US). The pek force (kg cm 2 ) ws then recorded. Met selenium content The selenium content in fresh met ws ssessed y commercil lortory using ICP-MS methods (gilent 7500cx ICP-MS, gilent Techmologies, Snt Clr, C, US). nlyticl procedures were performed following UNI CEI EN ISO/IEC 17025:2005 stndrds. Sttisticl nlysis ody weight, verge dily gin, met selenium content, sher force nd drip loss were nlysed y one-wy NOV (, 2011) considering the min effect of tretment. Colour prmeters, ph nd visul evlution score were nlysed y two-wy NOV using generl liner model for repeted mesures, considering the effects of tretment, storge time nd their interction (, 2011). The significnce level ws set nd discussed for P 0.05, while P 0.10 ws considered tendency. Results Finl ody weight, verge dily gin nd crcss chrcteristics did not differ etween groups (Tle 1). Met centesiml composition in the selected crcsses ws not ffected y tretment, while supplementtion mrkedly incresed the met selenium content (P < 0.001; Tle 2). The replcement of with tended to reduce sher force on cooked smples (P = 0.076; Figure 1). The Se source did not ffect thwing, cooking, or drip losses fter 8 dys of storge (Tle 2). During storge, the ph incresed (P < 0.001), ut ws not ffected y tretment (Tle 3). Regrding colour prmeters, lightness (L*) ws ffected y tretment (P < 0.01), storge time (P < 0.01), nd their interction (P < 0.05), Tle 1. Lest squre mens for the effect of selenium source during finishing phse on rering performnce Indices Groups SEM verge initil W, kg verge finl W, kg DG, kg d sodium selenite; selenium-enriched yest; W ody weight; DG verge dily gin P

4 96 Sodium selenite or selenium-enriched yest eef qulity Tle 2. Lest squre mens for the effect of selenium source during finishing phse on met chemicl composition, selenium content thwing, drip nd cooking loss of the 30 crcss/group Indices Groups 1 SEM P Cold crcss weight, kg Dressing percentge, % Humidity, % Crude protein, % Ether extrct,% sh, % Se, mg kg 1 dry mtter <0.001 Thwing loss, % Drip loss, % fter 8 dys of storge Cooking loss, % see Tle 1 nd the treted group ws chrcterized y significntly higher L* vlues. In the sme wy, redness (*) decresed with incresing storge time (P < 0.01), ut ws not ffected y selenium source or their interction. The treted group lso showed higher yellowness (*) (P < 0.01), which decresed in oth groups during storge (P < 0.01), ut ws not ffected y the interction etween tretment nd storge time (Figure 2). Considering lso the decresing trend of lightness nd redness, smples from nimls fed showed higher L* nd * stility during the first dys of storge (Figure 2). Met shelf-life ws lso ffected y tretment nd storge time (Tle 4). s expected, colour, odour, surfce wetness, nd overll ppernce scores decresed during storge (P < 0.001) nd the selenium source positively ffected ll of these Tle 3. Lest squre mens for the effect of selenium source during finishing phse on met ph during 8 dys of storge Dys of storge Met ph 1 2 SEM P(s) P(t) 3 <0.001 P(s t) ,2 see Tle 1; 3 s selenium source; t storge time; s t selenium source storge time kg kg m 2 3, , , , , , , , Figure 1. Lest squre mens (± SEM) for the effect of selenium source during finishing phse on sher force t 48 h post mortem (P = 0.076); sodium selenite; selenium-enriched yest Lightness, L* Redness, * Yellowness, * , , , ,00 36, ,00 32, , , , , , ,00 8, , , , , , , , , Dys of storge Dys of storge C Figure 2. Lest squre mens (± SEM) for the effect of selenium source during finishing phse on lightness (), redness () nd yellowness (C) during 8 dys of storge (, P 0.01;, P 0.05);, see Figure Dys of storge

5 C.. Sgoifo Rossi et l. 97 Tle 4. Lest squre mens for the effect of selenium source during finishing phse on colour, odour, surfce wetness nd overll ppernce score during 8 dys of storge Dys of storge Colour Odour Surfce wetness Overll ppernce 1 2 SEM SEM SEM SEM P(s) 3 <0.01 <0.05 <0.05 <0.01 P(t) 3 <0.001 <0.001 <0.001 <0.001 P(s t ) ,2 see Tle 1; 3 see Tle 3;, mens with different superscipts within row re significntly different t P 0.01 or P 0.05, respectively visul prmeters. The colour score ws higher in the group (P < 0.01) from the fourth dy, the odour score ws higher (P < 0.05) on the lst two dys, while surfce wetness ws higher (P < 0.05) strting from the fifth dy of storge. The overll ppernce enefited from these meliorting effects nd its score ws incresed y dministrtion of orgnic selenium (P < 0.01) strting from the fourth dy of storge. Discussion The sence of the effect of Se source on growth performnce nd crcss trits is consistent with other studies in fttening cttle (Nicholson et l., 1991; Cozzi et l., 2011), mle gots (Shi et l., 2011) nd lms (Vignol et l., 2009). Similrly, sence of n effect of Se source on met centesiml composition ws lso reported y Tylor et l. (2008) nd Cozzi et l. (2011) in eef, nd y Vignol et l. (2009) in lms. Given tht Se is minly implicted in improving immune response, s previously reported, this result ws expected, s the finl stge of the fttening cycle is not criticl stge for infectious diseses. Indeed the disese most impcting eef cttle production is ovine respirtory disese (Rdostits et l., 2007), which ffects, especilly, newly received eef cttle (Glyen et l., 1999). The rise in the musculr Se concentrtion chieved y supplementing in respect to is consistent with the findings of Juniper et l. (2008) nd Cozzi et l. (2011) in eef, Juniper et l. (2009) nd Vignol et l. (2009) in lms, nd Shi et l. (2011) in growing mle gots. This confirms the greter iovilility of the orgnic compred with the inorgnic form. Indeed, t the rumen level, prt of the dietry SeMet, the prevlent form in the provided, is incorported into cteril protein, thus ecoming prt of metolizle protein. The remining mount is efficiently sored t the gut level through methionine crriers. In contrst, most of the selente is reduced to selenite nd susequently converted into wekly sorle compounds or used y microes to synthesize seleno-mino cids. The escped selente is ctively sored vi cotrnsport pthwy long with sodium ions, while selenite is sored vi pssive trnsfer. fter sorption, SeMet cn e incorported into proteins, in replcement of met-hionine, or ctolized nd the Se utilized for SeCys synthesis. The sored selenite is reduced insted to selenide, utilized to synthesize SeCys, while the portion not immeditely converted to SeCys is methylted nd excreted (Weiss, 2005). Incresing the met Se content is n importnt outcome, s met is one of the mjor contriutors to Se intke in the humn diet nd low Se sttus is linked to higher risk of mortlity, poor immune function, nd cognitive decline (Rymn, 2012). Moreover, in the mjority of EU countries, Se intke is lower thn the recommended vlue of 55 µg dy 1 (Rymn, 2004; Thomson, 2004). Overll, from n economic perspective, given the short-term supplementtion nd, especilly, the smll mount provided, it is possile to conclude tht the replcement of inorgnic Se with Se-enriched yest does not significntly ffect eef production costs. Moreover, the higher iovilility cn llow producing selenium-enriched met with consequently higher dded vlue. n increse in eef tenderness hs lso een reported y Cozzi et l. (2011). In our tril we found reduction of sher force t 48 h post mortem nd, considering the positive reltionship found etween met selenium content nd glutthione peroxidse (GSH-Px) ctivity (Juniper et l., 2008),

6 98 Sodium selenite or selenium-enriched yest eef qulity this my e explined y lower clpin oxidtion due to the highest GSH-Px ctivity in the group. Indeed, during post mortem musculr proteins undergo to mrked oxidtion tht could impir met tenderness y decresing protese ctivity nd inducing myofirillr protein cross-linking (Huff Lonergn et l., 2010; Estevez, 2011; Lund et l., 2011). s reviewed y the sme uthors, oth µ- nd m-clpins contin histidine nd cysteine thiol groups in their ctive site; these groups re highly susceptile to oxidtion resulting in inctivtion. Moreover, cross-linking of myofirillr proteins reduces their susceptiility to degrdtion nd improves the strength of the myofirillr structure, incresing met toughness. In this scenrio, is possile to hypothesize tht the increse of musculr ntioxidnt ctivity due to the higher Se content could hve reduced the extent of enzymtic nd myofirillr protein oxidtion. This hypothesis is supported y the findings of Rowe et l. (2004,), who reported tht dietry ntioxidnt supplementtion in eef (vitmin E) reduced protein oxidtion, positively promoting post mortem proteolysis nd, consequently, eef tenderness. Nevertheless, further investigtions re necessry to etter clrify the role of Se in the met tenderiztion process, protese ctivity, nd protein oxidtion. The lck of effect of selenium source on met drip loss is consistent with the findings of Cozzi et l. (2011) in eef nd Vignol et l. (2009) in lms. In contrst, some uthors reported n increse in WHC in sujects supplemented with n orgnic selenium source in respect to those fed n inorgnic one in studies on poultry (Downs et l., 2000; Wng et l., 2011,) nd pigs (Mteo et l., 2007; Zhn et l., 2007). Regrding met ph, our findings re in greement with those of Zhn et l. (2007) in pigs, Vignol et l. (2009) in lms, nd Juniper et l. (2011) in turkeys. Cozzi et l. (2011), in contrst, reported higher eef ph fter 6 dys of geing in nimls fed orgnic selenium compred with those fed sodium selenite or switched from it to selenium yest in the lst 70 dys, ut no differences were found y the sme uthors t 11 dys post mortem or etween nimls fed for the entire fttening period with sodium selenite or switched to selenium yest, s we did in this tril, t oth geing times. Furthermore, Wng et l. (2011) found tht the ph tend to e higher in the rest of roilers fed with selenomethionine in comprison with those receiving sodium selenite. Improvement of lightness due to supplementtion of orgnic selenium ws lso reported y Cozzi et l., (2011), who found n incresed L* vlue fter 6 nd 11 dys of vcuum pckged geing. In contrst, Vignol et l. (2009) reported no effects of selenium source on lm met lightness, redness nd yellowness during 9 dys of simulted disply life. The sme uthors did not report differences in met redness or yellowness. Regrding these two prmeters, however, Tylor et l. (2008) found tht met from cttle fed selenium-enriched diet hd higher Se content nd tended to hve higher verge * nd * during 12 dys of disply, compred with nimls fed n unenriched diet. Given tht lightness is relted to met protein structure (McDougll, 1982) nd not with myogloin sttus (McKenn et l., 2005), therefore, this excluded reduction of myogloin oxidtion s n explntion; the effect of orgnic selenium on this prmeter still remins to e clrified, considering lso the ove reported inconsistency etween studies. Conclusions Under the presented experimentl conditions, switching selenium supplementtion from sodium selenite to selenium-enriched yest during the lst two months of fttening did not ffect heifer performnce or met wter holding cpcity, ut improved met tenderness nd colour stility during storge, with positive impct on met shelf life. The present study lso confirmed tht short-term supplementtion represents vlid strtegy for incresing met Se content, n importnt outcome from the mrket nd humn helth perspectives. Further investigtions re necessry to etter clrify the mgnitude of nd mechnisms involved in the effects of orgnic Se supplementtion on met colour, s well s the potentil impct on the post mortem tenderiztion process nd protein oxidtion. References OC, ssocition of Officinl nlyticl Chemists, Officil Methods of nlysis. 15 th Edition. rlington, V Cntor.H., The role of selenium in poultry nutrition. In: T.P. Lyons, K.. Jcques (Editors). iotechnology in the Feed Industry: Proceedings of lltech s 13 th nnul Symposium. Nottinghm University Press, Nottinghm (UK) Chuhn S.S., Celi P., Ponnmplm E.P., Leruy.J., Liu F., Dunshe F.R., ntioxidnt dynmics in the live niml nd implictions for ruminnt helth nd product (met/milk) qulity: role of vitmin E nd selenium. nim. Prod. 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