Amino Acid Density and L-Threonine Responses in Ross Broilers 1,2

Transcription

1 Interntionl Journl of Poultry Science (): 8-6, 00 ISSN Asin Network for Scientific Informtion, 00 Amino Acid Density nd L-Threonine Responses in Ross Broilers, M.T. Kidd, W.S. Virden, A. Corzo, W.A. Dozier, III nd D.J. Burnhm Deprtment of Poultry Science, Mississippi Stte University, Mississippi Stte, MS , USA Agriculture Reserch Service, United Sttes Deprtment of Agriculture, Mississippi Stte, Mississippi , USA Ajinomoto Hertlnd, Chicgo, IL 606, USA E-mil: Astrct: An experiment ws conducted to determine the effects of feeding roilers diets differing in mino cid density during the finisher period. Also, the impct of L-threonine ddition to high (H) or low (L) mino cid density diets ws determined. Ross x 708 mle roiler chicks were plced in floor pens nd fed common diets from d to tht met or exceeded NRC (99) recommendtions. From d to, roilers were fed diets consisting of H (digestile Lys of 0.88%, TSAA of 0.69%, nd Thr of 0.9%) or L (digestile Lys of 0.8%, TSAA of 0.6%, nd Thr of 0.%) mino cid density, with or without dietry L-threonine (9 replictions ech of tretments). On d, live performnce nd crcss chrcteristics were determined. There were no interctions or L-threonine effects (P>0.0) on live performnce or crcss trits of roilers. Body weight nd feed intke did not differ due to mino cid density. Birds fed diets contining H mino cid density hd higher (P< 0.0) rest met (P = 0.06 reltive to BW; P = 0.0 reltive to crcss weight) nd lower (P<0.0) feed conversion nd percentge dominl ft thn irds fed diets with L mino cid density. Minimizing essentil mino cid excesses through dietry L-threonine inclusion did not improve or dversely ffect performnce. An economic nlysis indicted tht decresing mino cid density (H to L) in to d roilers resulted in n income loss of $0.0/live ird. Key words: Amino cid density, roiler, threonine, crcss Introduction 6 to d) showed enefits to high mino cids in oth Mximizing monetry mrgins over input costs in periods, nd tht the roiler s response ws dependent integrted roiler opertions, or ny other sles driven on the erly ( to 6 d) period (Eits et l., 00). usiness, must e key gol to ttin long term profits. Reserch evluting the impct of mino cid density in Becuse feed represents over hlf the live production commercil roilers (Ross 08, Ross 08, nd Aror costs in n integrted roiler opertion, feed cost Acres Plus) demonstrted the positive impct of high reduction rther thn feed cost optimiztion is often mino cid density diets (unlnced nd lnced), in employed. Furthermore, chnge occurs continuously ddition to ccentuting the importnce of mino cid within nd etween commercil roiler strins (i.e., nutrition from d 0 to (Lemme et l., 00; Corzo et l., growth nd tissue ccretion rtes) deeming nutritionl 00; Kidd et l., 00). Becuse high mino cid optimiztion s prolemtic. Hence, feeding progrms nutrition erly in ird s life is economiclly desirle, should e strin specific (Smith nd Pesti, 998), while this reserch ws conducted to ssess the impct of ddressing feed cost optimiztion. feeding low nd high mino cid plnes of nutrition in In n effort to optimize feed cost nd overll profit, the finishing period. It ws lso n ojective to reserch studies delineting the impct of mino cid determine the impct of L-threonine ddition to the diets density in high commercil roiler strin crosses differing in mino cid density. hve incresed. Both erly nd lte developing roiler strins hve een shown to hve suppressed rest Mterils nd Methods nd thigh s during summer months when mino Birds nd mngement: Three hundred-fifty Ross x 708 cid density is reduced (Dozier nd Morn, 00). Live mle roiler chicks were otined from commercil performnce nd crcss responses of mle roilers to htchery, divided into two groups, nd plced in two mino cid density is greter thn tht of femle roilers eqully constructed nd designed rooms mesuring.6 (Lemme et l., 00; Eits et l., 00; Corzo et l., 00; x 9.0m. Vccintion progrm consisted of Mrek s virus Kidd et l., 00). Feeding Hyro-G roilers low nd high in ovo t d 8 of incution, nd corse spry of plnes of lnced mino cids to energy ( to 6 nd Newcstle disese virus nd infectious ronchitis virus 8

2 Tle : Test diets (%) nd nutrient composition Ingredients High density Low density L-Threonine + L-Threonine - L-Threonine + L-Threonine Corn Soyen mel Poultry ft Poultry mel Diclcium Phosphorus Limestone NCl Premix DL-Met L-Lys Hcl Scox Hy D Choline Cl L-Threonine Clculted composition d Lys, % d TSAA, % d Thr, % d Ile, % d Vl, % d Trp, % d Arg, % CP, % ME, kcl/kg,,,, C, % Avil. Phosphorus, % N, % Premix provided the following per kg of diet: Vitmin A (Vitmin A cette) 7,78 IU; choleclciferol,00 IU; Vitmin E (source unspecified) 0 IU; mendione, 0.9 mg; B, mg; choline, 79 mg; rioflvin,.0 mg; nicin, mg; D-iotin, 0.06 mg; pyridoxine, 0.9mg; ethoxyquin, 8mg; mngnese, mg; zinc, 0mg; iron, 8mg; copper, 7mg; iodine, mg; selenium, 0.mg. Digestile coefficients were sed on True digestiility of essentil mino cids for poultry, Revision 7, Ajinomoto Hertlnd LLC. t d of ge. Susequent vccintions were not (using the weight of mortlity to correct feed dministered. Birds were provided h light until consumption dt), nd mortlity. All diets were stem termintion of the experiment. pelleted nd were sed on corn, soyen mel, nd poultry mel (Tle ). Diets were formulted on the Design, Mesurements nd dietry tretments: At following digestile mino cid rtios to lysine: totl d of ge, irds were trnsferred to the experimentl sulfur mino cids, 78; threonine, 67; isoleucine, 7; fcility rndomly, plced in floor pens (6 pens vline, 8; tryptophn, ; nd rginine, 7. Dietry mesuring.08 m ech), nd weighed y pen (9 irds tretments consisted of high (H) or low (L) mino cid per pen). The experimentl fcility ws curtin-sided density with or without the inclusion of L-threonine ( house. Forced-ir gs heters were used for heting. tretments ech hving 9 replictions). Therefore, diets Cooling ws ccomplished with evportive cool cells differed only in mino cid levels s mino cid rtios to nd negtive pressure ventiltion. Ech pen contined lysine were similr. L-threonine ws llowed to enter pn feeder, nipple drinker line ( nipples per pen), lest cost formultion nd the isoleucine minimum nd soft - wood shvings s edding. The soft - served s the nutrient constrin in formultion to which wood shvings hd een previously used s edding crude protein ws set in the tretment diets contining for numerous flocks. Experimentl feed ws weighed y L-threonine. Composite smples of test diets were pen, dded to the pn feeders (6 kg cpcity), nd otined fter pelleting to ssure nutrient vlues were in irds consumed the experimentl diets to d. Live greement with those clculted. performnce mesurements for the to d period consisted of BW gin, feed intke, feed conversion, Mesurements: Pen BW were otined t d nd. 9

3 Tle : Impct of diets differing in mino cid density with or without L-Thr on live performnce nd crcss trits in Ross x 708 mle roilers from to d Dietry tretments BW Feed Feed Crcss Crcss Brest Brest Adominl gin intke conversion 6 7 ft Diet L-Thr Kg g/ird/d Kg/Kg (%) H L H H L L SEM Source of Vrition Diet L-Thr Diet x L-Thr Diets were formulted to meet digestile rtios to lysine nd thus, lthough diet density differs, diet rtios to Lys do not. CP levels for H nd L in the diets without L-Thr (-) were 7.8 nd 6.70, respectively, nd CP levels for H nd L in the diets with L-Thr (+) were 7.0 nd.98, respectively. L-Thr (L-threonine) ws llowed to enter formultion freely in diets series (+), nd its inclusion level in the H nd L diets ws 0.0 nd 0.09, respectively. Represents crcss without dominl ft reltive to processing BW. BW t processing verged.6 kg/ird. Represents crcss with dominl ft reltive to processing BW. Represents Pectorlis mjor, Pectorlis minor, nd ck ri met (skin-less, one-less) reltive to live BW t processing. 6 Represents Pectorlis mjor, Pectorlis minor, nd ck ri met (skin-less, one-less) reltive to crcss weight. 7 Represents dominl ft reltive to processing BW. Mortlity ws mesured dily. Body weight gin, feed Sttisticl nlysis: The design ws rndomized intke, nd feed conversion were mesured for the to complete lock. The four tretments of the fctoril d period. Six irds per pen were selected for rrngement of two mino cid densities nd two L- processing t d, weighed in group, nd trnsported threonine levels were nlyzed using the Generl Liner to the pilot processing plnt. Processing methodology Models procedure of SAS (SAS Institute, 998) follows tht previously descried (Kidd et l., 00). Differences mong mens (P < 0.0) were seprted Crcss mesurements otined were crcss weight, with repeted t test using the LSMEANS option of SAS dominl ft weight, nd totl rest met weight (SAS Institute, 998). Pen ws the experimentl unit for (skinless). ll nlyses. Economic model progrm: Using Microsoft Excel (00), progrm ws creted to ssess monetry income for roiler chickens in de-one mrket fed H or L mino cid density ecuse these diets differed gretly in cost nd impct ird performnce in differing mnners. The cost inputs in the model were sed on Ferury 00 ingredient nd chicken prices ($. USD for skinless rest met) nd roiler performnce ws tken from responses presented herein s ffected y dietry mino cid density with nd without L- threonine. Diet costs for H nd L, without L-threonine, were $.0 nd $8.0 USD/metric ton, respectively. The mino cid contriuting feed ingredient prices ($, USD) per metric ton were: corn, 87.08; soyen mel,.9; poultry mel, 09., DL-methionine, 87.8; nd L-lysine HCl, 6.8. The mthemticl clcultions in the economic progrm were used to clculte monetry return per ird. Results nd Discussion The diets formulted to differ in mino cid density were esily chieved s clculted mino cid nd protein composition ws in greement with nlyzed levels. The ility of diet reduced in CP to support growth nd tissue ccretion needs of mle roilers in the finishing period ws tested. Moreover, further decrese in the mino cid pttern ws ccomplished y the dietry inclusion of L-threonine in n verge inclusion level of 0g/metric ton. It must e pointed out tht lthough the H nd L diets hd decrese in CP with the ddition of L-threonine, 0.8% nd 0.7%, respectively, they met the essentil mino cid rtios to lysine. Hence, the diets fortified with L-threonine fostered minimiztion of essentil mino cid excesses: which cn e costly. No interctions or L-threonine effects occurred in the results presented herein (Tle ), indicting tht diets minimized for mino cid excesses (i.e., those 60

4 Fig. : Impct of mino cid diet density from d to on monetry income per ird t d. Brs represent income in $ USD for irds fed H diets nd irds fed L diets. Growth performnce inputs in the economic model from to d were the sme etween tretments. Diet costs for H nd L in $ USD/metric ton were.0 nd 8.0, respectively. contining L-threonine) resulted in equl ird responses in comprison to irds fed diets without L-threonine nd mrginlly higher in CP. These results gree with pst findings in tht the dietry inclusion of L-threonine (up to 600 g/metric ton) did not ffect growth or crcss ttriutes in roilers in comprison to irds fed diets without L-threonine (Kidd et l., 00). Thus, lthough the diets in the reserch presented herein nd tht of Kidd et l. (00) hd dequte levels of essentil mino cids, the mrginl reduction in levels of the less limiting mino cids (i.e., isoleucine, vline, rginine, nd tryptophn) did not impir growth or crcss chrcteristics. Body weight, feed intke, crcss, nd rest met reltive to live ody weight did not differ in irds fed vrying levels of mino cid density. However, irds fed H mino cid density hd lower (P < 0.0) feed conversion nd dominl ft, nd greter (P < 0.0) rest met reltive to crcss contining dominl ft percentge thn irds fed L mino cid density diets. These findings re in greement with recent reserch on mino cid density in mle roilers (Eits et l., 00; Lemme et l., 00; Corzo et l., 00; Kidd et l., 00). The reserch y Kidd et l. (00) points to economic dvntges of dietry L-threonine inclusion s indicted y good roiler performnce in diets with mrginlly reduced CP nd cost. However, determining the economic optimiztion of mino cid feed progrms in high roilers is prolemtic. An economic model ws creted to ssess monetry income in prcticl sitution in dietry tretments presented herein tht differed (P < 0.0; i.e., mino cid density), s diets differing in L-threonine did not differ. Hence, roiler growth nd crcss trit predictions using mens generted from irds fed H nd L diets ws compred in model using Ferury 00 feed ingredient prices in the United Sttes. Although the L diet ws lower ($. USD/metric ton) in cost compred to the H diet, it resulted in net loss of $0.0/ird to mrket s compred to irds fed the H diet (Fig. ). It hs een suggested tht feeding progrms designed to meet mino cid needs of high roilers must not e low in ny criticl mino cid minimum in pre-strter or strter periods (Kidd et l., 00). Eits et l. (00) indicted tht mino cid feeding progrms from to 6 nd 6 to d of ge should oth e optimized to support good growth nd rest ccretion. Although decresing mino cid density results in lrge decreses in diets costs, especilly in the finishing periods, cre must e tken s results presented herein indicte tht the feed reduction cost s chieved y dietry mino cid density reduction my not e profitle. References Corzo, A., C.D. McDniel, M.T. Kidd, E.R. Miller, B.B. Boren nd B.I. Fncher, 00. Impct of dietry mino cid concentrtion on growth, crcss, nd uniformity of roilers. Aust. J. Agri. Res., : -8. Dozier, W.A., III. nd E.T. Morn, Jr., 00. Response of erly- nd lte- developing roilers to nutritionlly dequte nd restrictive feeding regimes during the summer. J. Appl. Poult. Res., 0: Eits, R.M., K.P. Kwkkel, M.W.A. Verstegen nd G.C. Emmns, 00. Responses of roiler chickens to dietry protein: effects of erly life protein nutrition on lter responses. Br. Poult. Sci., : Inform Economics, 00. Suject: Feed Ingredient Weekly, 8 Ferury 00. Vol. 9, Issue 07. http// Accessed Ferury 00. Kidd, M.T., C.D. McDniel, S.L. Brnton, E.R. Miller, B.B. Boren nd B.I. Fncher, 00. Incresing mino cid density improves live performnce nd crcss s of commercil roilers. J. Appl. Poult. Res., : Kidd, M.T.,C.D. Zumwlt, D.W. Chmlee, M.L. Crden nd D.J. Burnhm, 00. Broiler growth nd crcss responses to diets contining L-threonine versus diets contining threonine from intct protein sources. J. Appl. Poult. Res., :

5 Lemme, A., S. Mck, P.J.A. Wijtten, D.J. Lnghout, G.G. Irish nd A. Petri, 00. Effects of incresing levels of dietry idel protein on roiler performnce. Pges 8-6 in: Proc. th Aust. Poult. Sci. Symp., Sydney, Austrli. Microsoft Excel, 00. Microsoft Corp., Redmond, WA. Ntionl Reserch Council. 99. Nutrient Requirements of Poultry. 9th Rev. ed. Ntl. Acd. Press, Wshington, DC. SAS Institute, 998. SAS User s guide: Sttistics Version 7.0. SAS Institute Inc., Cry, NC. Smith, E.R. nd G.M. Pesti, 998. Influence of roiler strin cross nd dietry protein on the performnce of roilers. Poult. Sci., 77: This is Journl Article Numer J-0688 from the Mississippi Agriculturl nd Forestry Experiment Sttion. Use of trde nmes in this puliction does not imply endorsement y the Mississippi Agriculturl nd Forestry Experiment Sttion of the products, nor similr ones not mentioned. To whom correspondence should e ddressed: mkidd@poultry.msstte.edu Mention of trde nme, proprietry product, or specific equipment does not constitute gurntee or wrrnty y the USDA nd does not imply pprovl to the exclusion of other products tht my e suitle. Arevition key: H (high), L (low) 6