Effect of Rearing Program, Body Conformation and Protein Level of Breeder Feed on Broiler Breeder Hen Reproductive Performance

Transcription

1 Interntionl Journl of Poultry Science (): , 0 ISSN Asin Network for Scientific Informtion, 0 Effect of Rering Progrm, Body Conformtion nd Protein Level of Breeder Feed on Broiler Breeder Hen Reproductive Performnce J.A. Englnd, J.R. Moyle, D.E. Yoho, R.K. Brmwell, R.D. Ekmy, R. Kriseldi nd C.N. Coon Center of Excellence for Poultry Science, University of Arknss, Fyetteville, AR-770, USA University of Mrylnd Extension, Lower Estern Shore Reserch nd Eduction Center, 766 Nnticoke Rod, Slisury, MD-80, USA Dow Agro Sciences, LLC. Indinpolis, Indin, USA 0 Poultry Science Building, 60 Lem Morrison Drive, Auurn, AL-689, USA Astrct: The effect of pullet growth curve on ody conformtion nd susequent reproductive performnce nd effect of reeder feed protein level on reproductive performnce ws determined. The cost effectiveness of the different progrms ws evluted. Co 700e pullets were rered from dy of ge in floor pens. Ech pen ws ssigned to one of two growth curves from 6 weeks of ge to housing t weeks of ge. One growth curve followed stndrd (SD) ody weight curve nd second followed lighter (LI) ody weight curve. At weeks of ge, hlf of the hens from ech of the growth curves were ssigned to one of two reeder diets. Hlf of the hens were fed low (LO)-protein (%) reeder diet nd hlf were fed higher (HI)-protein reeder diet (6%) during the production phse. Pullet growth curve significntly ffected ody weight through 0 weeks of ge. The protein level of the reeder feed significntly ffected ody weight t 5 nd 0 weeks of ge. Pullet growth curve ffected ody conformtion, ut did not ffect ge of first egg. Pullet growth curve did not ffect egg weight. Protein level of the reeder feed significntly ffected egg weight; hens fed the HI-protein diet lid hevier eggs. Egg production ws not ffected y pullet rering growth curve (p = 0.085) or protein level (p = 0.78) of the reeder feed. Feeding LO-protein diet resulted in feed cost svings. The feed cost of SD rered hens fed LO-protein diet ws $0.07 per hen less thn for those fed HI-protein diets. The feed cost of LI rered hens fed LO-protein diet ws $0.66 per hen less thn for those fed HI-protein diet. Key words: Broiler reeder, growth curve, protein, egg production, ody conformtion INTRODUCTION Renem et l. (007) noted the genetic potentil for roiler growth hs incresed drmticlly over the pst 0 yers, ut reeder stock trget ody weights (BW) hve only seen smll chnges. Breeder stock ody weights re restricted to improve the welfre of the irds nd improve reproductive performnce. Mny pproches hve een tken to rering pullets nd feeding roiler reeders in order to improve reeder production. Sun nd Coon (005) seprted group rised pullets sed on BW. Wilson et l. (995), Roinson et l. (005), Roinson et l. (007), Renem et l. (007), Zuidhof et l. (007), Hrper (008) nd De Beer nd Coon (009) vried the trget BW growth curve, shpe of the growth curve, or ge of most growth restriction to find out wht BW or type of growth curve resulted in the est performnce in the production house. These growth curves were within 0-5% of primry reeder trget weights t housing or curves converged t weeks of ge. Reserch y Roinson et l. (005), Roinson et l. (007), Renem et l. (007) nd Zuidhof et l. (007) indicte there my e strin differences in the production house in response to different pullet growth curves. Currently, mny elieve there is criticl ge period for proper physiologicl development for reproductive success. In generl, most reserch with pullet rering BW progrms hve found influences on hen BW, ody conformtion, ge t first egg, settle eggs nd weight of eggs otined during the production period. The protein intke of roiler reeders hs lso een suggested to influence the reproductive performnce of reeder hens. Primry reeders recommend formulting diets sed on digestile or n idel mino cid profile. They lso give trget or rnge of kcl intke nd nutrient intke recommendtions for hens t pek production. For the purpose of ssessing the rnge of crude protein intke eing fed to reeder hens in the Industry, crude protein ws extrpolted from nutrient intke recommendtions provided y primry reeder compnies (Co-Vntress, 0; Avigen, 0-d; Avigen, 0; Hurd, 0-d). The crude protein Corresponding Author: Crig N. Coon, University of Arknss, Center of Excellence for Poultry Science, Fyetteville, AR-770, USA 670

2 Int. J. Poult. Sci., (): , 0 (CP) intkes rnge from.6 to 7.5 g CP//d t pek feed llotment. Joseph et l. (000) reported hens fed. g CP lid fewer nd lighter eggs compred to hens fed.6 or 6.6 g CP//d. Joseph et l. (00) fed diets with 6 or 8% CP with pek protein intkes of 6. or 8.8 g CP//d nd reported one strin of hens performed etter t lower CP intkes. Sprtt nd Leeson (987) reported hens fed 5 g CP//d t pek consumption lid hevier eggs ut egg production ws reduced y.6% compred to hens fed 9 g CP//d. Lopez nd Leeson (99) showed hens fed lower intkes of protein my ly more eggs compred to hens fed higher intkes of Person nd Herron (98) reported tht reeders consuming 7 g protein intke per dy produced n incresed numer of ded nd deformed emryos nd decresed htchility of fertile eggs compred to reeders consuming. g of protein intke per ird per dy. Lower levels of protein consumption mye ssocited with lower egg weights nd lower hen weights. Recently, Ekmy et l. (0) showed roiler reeders fed dequte digestile mino cids using n idel profile only need 0 g of digestile crude protein per dy (digestile essentil mino cids nd digestile non-essentil mino cids) to mximize egg mss nd reeder ody weight gin. The reserchers utilized dietry glutmic cid to provide dditionl mino cid nitrogen ove the essentil mino cid requirements. MATERIALS AND METHODS Bird housing nd mngement: Four thousnd two hundred nd forty dy old Co 700 (high yielding) pullets were weighed nd rndomly ssigned to sixteen 0.67m x 5.8m floor pens (65 pullets per pen). The house ws solid sided nd tunnel ventilted. Six hundred dy old Co cockerels were weighed nd plced in two 5. x 6.0 M floor pens. Ech pen ws equipped with hnging feed cns to provide minimum of 5. cm of feeder spce per ird. Ech pen ws equipped with nipple drinker system. The pullets hd n overll mortlity of.7% from 0 to weeks of ge nd miss sexed irds were removed prior to housing t weeks of ge. At weeks of ge.080 pullets nd 80 roosters were trnsferred to solid-sided, tunnel ventilted production house. Birds were housed 85 hens nd 0 roosters per pen in 8 pens. The roosters were lter reduced to 9 mles per pen. Ech pen mesured.7 M x.7 M. Ech pen ws equipped with nipple type drinkers nd hnging cn type feeders. Dily ird mngement ws sed on the Co Breeder Mngement Guide (Co Vntress, 0) nd personl communiction with Co-Vntress stff. Dy length in pullet house ws h of light from 0 to dys of ge, from to7 dys of ge dy length ws 6 h, from 8 to dys of ge dy length ws h nd from Tle : Clculted nutrient content of pullet diets. Nutrient Chick strter Pullet grower ME kcl/kg CP (%) Lysine (%) Methionine+cystine (%) Clcium (%) Phosphorus-non-phytte (%) Tle : Low protein (LO) nd high protein (HI) reeder diets Ingredient LO-Protein (%) HI-Protein (%) Corn 8.5% CP SBM 7.7% CP Limestone Whet midds 6.8. Ft.0.0 Diclcium phosphte Slt Sodium icronte Methionine Choline chloride Vitmin reeder premix Trce minerl Copper sulfte Propionic cid Selenium Premix-.06% Ethoxyquin Nutrient ME kcl/kg CP (%) (clculted) CP (%) (nlyzed) Ft (%) Clcium (%).0.0 Phosphorus-Non-phytte (%) Totl Phosphorus (%) Clculted digestile Lysine (%) Methionine (%) TSAA (%) Isoleucine (%) Phenyllnine (%) Phenyl nd Tyro (%).9.9 Threonine (%) Vline (%) dys of ge until housing, dy length ws 8 h. At dys of ge, the light intensity ws reduced to etween 0.75 nd foot cndle t ird level. When irds were moved to the production house t week of ge, dy length ws incresed to h of light; t weeks of ge dy length ws incresed to h of light. The dy length ws incresed to 5 h of light when hens reched 5% production nd t 60% production, dy length ws incresed to 6 h of light. Birds were vccinted ccording to the schedule used y locl integrtor. Bird helth ws monitored nd lood smples sumitted s required to the Stte L for NPIP certifiction. This study complied with the provisions of the Institute Animl Cre nd Use Committee s specified y the Animl nd Plnt Helth Inspection Service, USDA in 9 CFR Prt (-9). 67

3 Int. J. Poult. Sci., (): , 0 Experimentl design, mesurements nd feeding: From 0 to weeks of ge, pullets nd cockerels were fed the sme diets regrdless of tretment (Tle ). Chick strter, 860 kcl ME/kg nd 9% CP, ws fed from 0 to weeks of ge. Pullet grower, 86 kcl ME/kg nd 5% CP, ws fed from to weeks of ge. Birds were fed everydy to dys of ge. Beginning t dys of ge, the feeding progrm ws chnged to four-three feeding schedule. At sixteen weeks of ge, irds were plced on five-two feeding schedule nd t weeks of ge irds were plced on everydy feeding. At weeks of ge, hlf of the pullets from ech growth curve were ssigned to one of two different reeder hen feeds giving x fctoril rrngement (two pullet growth curves x two hen feeds). There were replictions per tretment. The two reeder diets (Tle ) were formulted to contin % (LO-protein) or 6% (HI-protein) CP. Both reeder diets were formulted to contin 865 kcl ME/kg,.% clcium nd 0.5% ville P. Both reeder diets were formulted to provide the digestile mino cid requirements for reeders s reported y Coon et l. (006). Proximte nlysis showed the feeds were similr to wht ws formulted (Tle ). Roosters were fed the % CP reeder diet eginning t weeks of ge. Cockerels were rered following ody weight recommendtions for the Co mle. From 0 to 5 weeks of ge pullets were rered following trget ody weights for modified Avin K growth curve. At 5 weeks of ge, ech pen of pullets ws weighed nd ssigned y verge ody weight to one of two growth curves (8 pens per growth curve). The stndrd (SD) growth curve continued to follow trget ody weights for modified Avin K growth curve nd light (LI) growth curve followed trget ody weights for.57% lighter ody weight hen t housing. At weeks of ge, the trget ody weights were nd 56 g for the SD nd LI growth curves, respectively. The trget ody weights for LI growth curve hens (77 g) were 5% lighter thn SD growth curve hens (860 g), t 5 weeks of ge. From 0 to weeks of ge, rndom smple of t lest 5 irds per pen ws weighed weekly. Dily feed llotment (kg per 00 irds) ws djusted sed on trget ody weight nd the growth rte nd feed conversion from the previous week (Tle ). From weeks of ge until the end of the tril, 8 hens per pen were weighed weekly to monitor weight gin. At 5 weeks of ge, when production reched 5%, the dily feed lloction ws incresed for every 8-0% increse in production until 0 kcl ME per ird per dy ws eing consumed t 65% production (Tle ) for ll tretments. If the hens were gining weight too rpidly reltive to the increse in egg production the mounts of ech feed increse ws reduced to mintin lighter hen through the end of production. At 9 weeks of ge, feed intke ws reduced y 0. to 0. kg/00 irds to Tle : Dily nd cumultive feed mounts from one dy of ge to 5% production Trt Trt Trt Trt Age SD-HI Pro SD-LO Pro LI-HI Pro LI-LO Pro weeks kg/00 /d kg/00 /d kg/00 /d kg/00 /d Cumultive Feed from 0 weeks of ge to 5% production kg/00 irds $/00 irds $.7 $05.08 SD-HI Pro:Stndrd BW curve pullets-reeders in production fed high SD-LO Pro:Stndrd BW curve pullets-reeders in production fed low LI-HI Pro: Light BW curve pullets-reeders in production fed high LI-LO Pro: Light BW curve pullets-reeders in production fed low control ody weight. At pek production, hens were consuming 0 to kcl ME per ird per dy. After pek production, dily feed intke ws reduced weekly y mounts vrying from 0. to 0.8 kg/00 irds depending on ody weights nd rte of gin. Dily feed intke ws reduced ech week fter pek until hens were consuming 90 kcl ME per ird per dy (Tle ). At 65% production, hens were consuming.5 or.6 grms CP//d for hens eing fed LO-protein nd HI-protein diets, respectively (Tle ). All feeding mounts re reported s n mount per 00 irds per dy s this is the common prctice in industry. Cumultive feed mounts re lso reported s per 00 irds per period. The mounts ctully fed ech pen per dy were djusted to the numer of irds per pen nd djusted dily for ny mortlity. All pens on given tretment were fed t the sme rte (kg/00 irds/dy), or sme mount per ird per dy. Feed costs were clculted sed on locl feed mill ingredient prices (My 0) with no milling or delivery chrges included. Strter feed cost $0.8 per kg, grower feed cost $0.775 per kg; reeder LO-protein feed cost $0.99 per kg nd reeder HI-protein feed cost $0.697 per kg. 67

4 Int. J. Poult. Sci., (): , 0 Tle : Dily nd cumultive feed mounts from 5% production to weeks of ge Trt Trt Trt Trt Prod SD-HIPro SD-LO Pro LI-HI Pro LI-LO Pro (%) kg//d kg//d kg//d kg//d weeks pek prod Week post pek kcl kcl 65% prod weeks pek prod 0 g 65% 9 pek prod..0.. Cumultive feed intke kg/00 irds 5% prod to week of ge kg/00 irds $/00 irds $60.6 $570. $ $560.5 SD-HI Pro: Stndrd BW curve pullets-reeders in production fed high SD-LO Pro: Stndrd BW curve pullets-reeders in production fed low LI-HI Pro: Light BW curve pullets-reeders in production fed high LI-LO Pro: Light BW curve pullets-reeders in production fed low protein From strt of ly until the end of the study, 0 eggs were weighed weekly from every pen of reeders. Shnk nd keel length were mesured t, 8,, 6, 0 nd weeks of ge. As n indictor of level of mturtion, pullets were evluted for fleshing nd ft deposition. The Co Breeder Mngement Guide (Co Vntress, 0) recommended method for evlution of fleshing nd ft deposition ws used. Pullets were evluted for com nd wttle development nd pelvic spred s indictors of sexul mturity. At 0 weeks of ge, 0 eggs from hens eing fed HI-protein nd 09 eggs from hens fed LO-protein feed were collected nd sent to locl compny for progeny rering field tril. The progeny from these eggs were sexed nd rered to 8 dys of ge. They were fed common strter nd grower diet formulted to Co recommendtions. The tretments for rering study were sex of chick nd the level of protein in the feed fed the reeder hens. Chicks were weighed weekly. Averge ody weight nd uniformity were determined for ech tretment. Uniformity ws defined s the percent of chicks whose ody weight fell within 0% (plus or minus) of the verge. Sttistics were run using JMP progrm (008). Completely rndomized design with x fctoril rrngement ws used to nlyze the dt.there were no significnt interction etween pullet growth curve nd hen feeding progrm so only min effects re reported nd significnt differences seprted using the Student s t-test. RESULTS AND DISCUSSION Totl feed mounts: Pullets nd cockerels in rering period were not fed d liitum. The irds were fed controlled dily mount of feed. Sttisticl nlysis of differences for totl feed consumed nd cost of feed etween tretments could not e determined ecuse ll irds were fed the sme mount of feed per ird per dy. However, pullets rered on the SD growth curve consumed 0.9 kg per 00 irds (cumultively) compred to kg per 00 irds rered on the LI growth curve from dy of ge to 5% production (Tle ). From dy of ge to 5% production, LI growth curve rered pullets consumed 7. kg less feed per 00 pullets thn SD growth curve rered pullets (Tle ). From dy of ge to 5% production, the feed cost per 00 pullets rered with the SD growth curve ws $.7 nd the cost per 00 pullets rered with the LI growth curve ws $05.08 (Tle ). This is difference of $8.6 per 00 pullets in ingredient feed costs. The SD growth curve rered hens, cross protein intke, cumultively consumed 60 kg feed per 00 hens from 5% production to weeks of ge (Tle ). The HI-nd LO-protein fed hens within the LI growth curve rered hens consumed 6 nd 60 kg per 00 hens from 5% production to weeks of ge, respectively (Tle ). The difference in cumultive feed consumed per 00 hens during this time period is due to differences etween tretments in the numer of dys etween ech feed increse (defined s 0% increse in egg production). The LI hens were to dys ehind SD hens in percent production nd, thus were to dys ehind in feed increses (Fig. ). However, the LI hens reched pek production t the sme time s SD growth curve rered hens (Fig. ). From 5% production to weeks of ge, LI growth curve rered hens consumed 6 nd 8 kg less feed per 00 irds thn SD growth curve rered hens eing fed HI-nd LOprotein diets, respectively. Bsed on My 0 ingredient costs, the feed cost per 00 hens from 5% production to weeks of ge for the SD rered hens verged $586.7 compred to $578.6 for the LI rered hens, thus mking difference of $7.85 per 00 hens. The lrger svings in feed costs per 00 hens from 5% production to weeks of ge is relized etween the hens fed the LO-protein nd HI-protein diets (Tle ). The feed cost per 00 hens from 5% production to weeks of ge for SD rered hens fed HI-nd LO-protein diets ws $60.6 nd $570., respectively. The feed 67

5 Int. J. Poult. Sci., (): , 0 Tle 5: Body weights of hens fed from 5 weeks of ge to housing for two different growth curves nd fed two different levels of protein during production Tretment Age (wk) Pullet Hen Trget BW (g) BW (g) SEM p-vlue CV 0 SD LI SD LI SD LI SD LI SD < LI HI pro LO pro Pullet * Hen trt interction SD LI HI pro LO pro Pullet * Hen trt interction SD LI HI pro LO pro Pullet*Hen trt interction SD LI HI pro LO pro Pullet * Hen trt interction 0.8 Numers within column with different superscripts differ significntly. SD: Stndrd BW curve pullets, LI: Light BW curve pullets, HI pro: Breeders in production fed high protein nd LO pro: Breeders in production fed low protein to weeks of ge for LI rered hens fed HI-nd LO-protein diets ws $ nd $560.5, respectively. The feed cost of LI rered hens fed LO-protein feed ws $6.6 less per 00 hens compred to hens fed HI-protein feed. Fig. : Weekly (%) egg production of hens rered to growth curves from 5 weeks of ge to housing nd fed protein levels during the lying cycle. SD-HI Pro: Stndrd BW curve pullets-reeders in production fed high SD-LO Pro: Stndrd BW curve pullets-reeders in production fed low protein, LI-HI Pro: Light BW curve pullets-reeders in production fed high LI-LO Pro: Light BW curve pullets-reeders in production fed low cost of SD rered hens fed LO-protein feed ws $.7 less per 00 hens compred to hens fed HI-protein feed. The feed cost per 00 hens from 5% production Body weights: Becuse there ws no significnt interction etween pullet growth curve nd protein level of the reeder feed only min effects will e discussed. At 6 weeks of ge, pullets weighed.8 g for the SD nd LI rered pullets (Tle 5, Fig. ). At 0 weeks of ge there were no significnt differences in BW for SD (.85 g) nd LI (.807 g) rered pullets. At, 5 nd 0 weeks of ge, the BW of LI growth curve rered hens ws significntly less thn BW of SD growth curve rered hens (Tle 5, Fig. ). The LI growth curve rered hens weighed, 8 nd 95 g less thn SD growth curve rered hens t, 5 nd 0 weeks of ge, respectively. The BW of SD nd LI growth curve rered hens were not significntly different t 5 nd 0 weeks of ge. Protein level of the reeder diet did not significntly ffect BW t 5 nd 0 weeks of ge (Tle 5). However, y 5 nd 0 weeks of ge, the BW of hens fed the HI-protein feed ws sttisticlly hevier thn hens fed the LO-protein feed (Tle 5). At 0 weeks of ge, the hens 67

6 Int. J. Poult. Sci., (): , 0 Fig. : Body weight of irds rered on growth curves from 5 weeks of ge to housing nd fed protein levels during the lying cycle. SD-HI Pro: Stndrd BW curve pullets-reeders in production fed high SD-LO Pro: Stndrd BW curve pullets-reeders in production fed low LI-HI Pro: Light BW curve pullets-reeders in production fed high LI-LO Pro: Light BW curve pullets-reeders in production fed low fed HI nd LO protein feeds weighed.679 nd.560 g in fleshing score due to growth curve (Tle 7) ws only per hen, respectively. The lower protein reeder feed n indictor tht t this ge the irds were in fct helped control weight gin of hens during the production seprted into two different growth weight groups. period. At no other ge were differences found in shnk, keel Both uniformity nd BW re of criticl importnce to nd pelvic mesurements or in ft nd fleshing score performnce during the reeder production phse. due to pullet rering growth curve or protein level of the Petitte et l. (98) reported reeder performnce ws reeder feed (Tle 6, 7 nd 8). Lilurn et l. (989) lso improved during the first 0 weeks of production in more found no effect of low protein diet or ody weight gin uniform flocks. Furthermore, Hudson et l. (00) on the skeletl growth chrcteristics of roiler reeder showed n overll improvement in numer of cumultive pullets. In series of experiments, De Beer nd Coon eggs produced y more uniform flock. It is therefore (006, 007) found no differences in shnk nd keel impertive to mintin uniformity to ensure optiml length of nd 8 wk-old hens fed different protein reeder production. At 0 weeks of ge, uniformity s levels or rered on different feeding regimens. De Beer indicted y the coefficient of vrition ws 0.9 nd nd Coon (006, 007) did find ody weight effect on 0.5% for the HI-protein nd LO-protein fed hens, shnk nd keel length. The reserchers reported pullets respectively, which indicted oth groups were uniform t 6 nd 6 wk of ge rered to hevier BW thn in BW. stndrd BW hd longer shnks nd keels thn pullets rered to less BW thn stndrd. De Beer nd Coon Skeletl conformtion: To evlute rediness of pullet reported tht keel length remined significntly longer in flock to ly nd to e light stimulted, field technicins the hevier BW pullets t wk. The shnk nd keel hndled the pullets nd evluted pelvic spred, ft lengths for wk old pullets for the SD nd LI groups in deposition nd fleshing scores of the irds. At 0 weeks the present study were not significntly different. Since of ge, SD growth curve rered pullets hd significntly the formtion of frme size is known to occur within the wider pelvic spred (0 mm) compred to LI growth first -5 wk of the rering period, it is unlikely tht curve rered pullets (8 mm) (Tle 6). However, pelvic ssorting the pullets into two ody weight groups t 5 spred ws not relile indictor of rediness to ly s wk would led to differences in shnk nd keel length t there ws no significnt difference in ge t first egg due wk. At weeks of ge there were no significnt to pullet rering growth curve (Tle 0). Averge ge t differences in shnk or keel length due to rering growth first egg ws. weeks of ge for the flock s whole curve or protein level of the reeder feed (Tle 8). with SEM of 0.0. Growth curve did not significntly ffect onset of ly in this study. Egg production, ge t first egg nd egg weights: At 5 weeks of ge, (05 d) pullets were ssigned to Roinson nd Roinson (99) found hens with low one of two growth curves (SD or LI) sed on verge ody weight t wks (.59 g) produced fewer eggs pen weight. At 6 weeks of ge, the significnt difference thn hens t medium nd hevier ody weights,

7 Int. J. Poult. Sci., (): , 0 Tle 6: Body conformtion of pullets rered on two growth curves SD growth curve LI growth curve Age dys Wgt (g) Shnk (mm) Keel (mm) Pelvic (mm) Wgt (g) Shnk (mm) Keel (mm) Pelvic (mm) x y xy Letters with different superscripts within row re significntly different p<0.05. SD: Stndrd BW curve pullets nd LI: Light BW curve pullets Tle 7: Ft nd fleshing scores*of hens rered on growth curves nd fed protein levels SD growth curve LI growth curve HI Pro LO Pro HI Pro LO Pro Age dys Flesh Ft Flesh Ft Flesh Ft Flesh Ft y x xy Letters with different superscripts within row re significntly different p<0.05. *Ft score ws -5 with eing idel for tht ge. Fleshing score ws -7 with eing idel for tht ge. Growth curve trgets were different from 6 weeks to weeks of ge. SD: Stndrd BW curve pullets, LI: Light BW curve pullets, HI: reeders in production fed high protein, LO: reeders in production fed low protein Tle 8: week ody conformtion of hens rered on growth curves nd fed protein levels Stndrd growth curve HI pro LO pro Age dys Wgt (g) Shnk (mm) Keel (mm) Pelvic (mm) Wgt (g) Shnk (mm) Keel (mm) Pelvic (mm) Light growth curve HI: reeders during production fed high protein nd LO: reeders during production fed low protein Tle 9: Eggs per hen housed of hens rered on growth curves nd fed Tle 0: Age t first egg for hens rered on growth curves nd fed protein levels levels of protein ---- Growth curve Protein level Growth curve Protein level Age SD LI HI Pro LO Pro SD LI HI Pro LO Pro wks EHH EHH EHH EHH week week week week Pro>F Pro >F SD: Stndrd BW curve pullets, LI: Light BW curve pullets, SD: Stndrd BW curve pullets, LI: Light BW curve pullets, HI: reeders in production fed high protein nd HI: reeders in production fed high protein nd LO: reeders in production fed low protein LO: reeders in production fed low protein nd.6 g, respectively. In the present study, the SD curve s compred with the Co stndrd. It hs een nd LI trget ody weight curves t wk were.56 hypothesized tht young roiler reeders rely on protein nd. g, respectively. The ody weights of oth of turnover nd endogenous lysine sources during erly these groups should support good production when egg production (Ekmy et l., 0, 0) compred to compred to the medium ody weights in Roinson nd older reeders tht re producing less htching eggs. Roinson s (99) study. The strong impct of the pullet growth curve on egg At weeks of ge in present study, there were no production in the present study is in line with wht would significnt differences in eggs per hen housed due to e expected under this hypothesis. A lrger hen with pullet rering growth curve or reeder feed protein level more ody reserves my support higher level of egg (Tle 9). At weeks of ge, LI growth curve rered production during the erly prt of production. hens hd lid 79. eggs per hen housed compred to At weeks of ge, hens fed HI-protein reeder feed 80.5 eggs per hen housed for SD growth curve rered hd lid 79.9 eggs per hen housed compred to 80. hens (Tle 9, p = 0.085). Bsed on ingredient feed eggs per hen housed for hens fed LO-protein feed cost (Tle nd ), the feed cost per dozen eggs ws (Tle 9, p = 0.78). Hens rered on the LI growth $.78 nd $.59 for LI nd SD rered hens, curve nd fed LO-protein reeder feed were slightly respectively. Ekmy et l. (0) recently reported ehind the other tretments coming into production, ut decrese in eggs per hen housed for hens rered to ll groups peked t the sme time nd t essentilly 0% lighter ody weight thn Co stndrd growth the sme level of production (Fig. ). Bsed on the 676

8 Int. J. Poult. Sci., (): , 0 Tle : Egg weights for hens rered on growth curves nd fed protein levels Growth curve Protein level Age wks SD (g) LI (g) Pro>F HI pro (g) LO pro (g) Pro>F < SD:Stndrd BW curve pullets, LI:Light BW curve pullets, HI:reeders in production fed high protein nd LO:reeders in production fed low protein Tle : 8-dy ody weights of roilers from hens fed LO or HI protein reeder feed Femle roilers Mle roilers Hen feed: Chick ge (d) ody weights HI pro (g) LO pro (g) HI pro (g) LO pro (g) Uniformity % % % % HI: reeders in production fed high protein nd LO: reeders in production fed low protein ingredient feed cost (Tle nd ), the feed cost per dozen eggs ws $.696 nd $.06 for hens fed HI-nd LO-protein reeder feed (this cost includes the rering period feed). There were no significnt differences in ge t first egg due to growth curve or reeder feed protein level (Tle 0). The SD growth curve rered hens reched ge t first egg t. weeks of ge compred to. weeks of ge for LI growth curve rered hens. Hens fed HI-protein in the production house produced the first egg t. weeks of ge compred to. weeks of ge for hens fed LO-protein feed. There ws no significnt interction etween pullet growth curve nd reeder feed protein level on egg weights. There ws no significnt difference in egg weight due to pullet growth curve (Tle ). The protein level of the reeder feed significntly ffected egg weight. Eggs from hens fed HI-protein feed were hevier thn those from hens fed LO-protein feed (Tle ). At ll ges, except 5 weeks of ge, hens fed HI-protein feed lid significntly hevier eggs: difference of 0.50 to.0 g per egg. Protein historiclly hs een found to increse egg weight (Summers nd Leeson, 99; Coon et l., 006); therefore the results presented here re in line with previous reports. Ekmy et l. (0) reported tht reeders rered with 0% hevier ody weight compred to the Co stndrd pullet growth curve resulted in incresed egg weight nd egg mss during the production period. In tht sme study, it ws lso shown tht 6 g of CP intke t pek production resulted in lrger eggs nd lrger chicks compred to g of CP intke. Ekmy et l. (0) reported non-significnt decrese of eggs per hen housed for reeders consuming 6 g CP compred to reeders consuming g CP. Furthermore, the higher CP intke resulted in significnt reduction in fertility (p = 0.007) nd numericl reduction in htchility (p = 0.0). These results suggest tht lower protein intke would result in more slele chicks. Ekmy et l. (0) proposed reeders need 0 g of digestile protein for optiml egg mss nd ody weight gin t pek production. Htch nd progeny grow-out feeding study: Eggs for htchility nd progeny grow-out study were sent to commercil htchery. The eggs were kept seprted y tretment ut not y pen, therefore, sttisticl replictions needed for showing significnt differences due to tretment in htchility nd progeny performnce were not ville. For the progeny grow-out study conducted y the compny, only finl BW nd uniformity were reported. One thousnd nd thirty eight eggs from hens fed LO-protein diets nd.0 eggs from hens fed HI-protein diets were trnsferred to the reeder s htchery. The htchility of these eggs ws nd 75.8% from hens fed LO-protein nd HI-protein diets, respectively. Lower fertility ws reported y Ekmy et l. (0) for reeder hens consuming ove 0 g intke of protein nd mino cids. Lopez nd Leeson (99) reported decresed fertility in eggs from hens fed 6% CP rther thn 0-%. Similrly, Person nd Herron (98) reported incresed emryonic mortlity in eggs from hens fed 7 g CP t pek rther thn g CP. Eggs from hens fed LO-protein diets produced 5.9% more htched chicks thn eggs from hens fed HI-protein diets. At 8 dys of ge, the femle roilers from hens fed LO-protein diets were 6% hevier thn femle roilers from hens fed HI-protein diets (Tle ). Mle roilers from hens fed LO-protein diets were % hevier thn from hens fed HI-protein diets. There ws. nd 6% improvement in the uniformity t 8 dys of ge of 677

9 Int. J. Poult. Sci., (): , 0 the femle nd mle roilers, respectively, for progeny of the LO-protein fed reeder hens compred to uniformity of progeny t 8 dys from HI-protein fed hens (Tle ). The lck of n dded progeny enefit from reeders fed higher levels of protein ws lso shown y Wilson nd Hrms (98). The reserchers did not see difference in 9d progeny weight when reeder protein intke ws vried etween 0 nd g CP per dy. Although the field htchility nd progeny dt reported herein could not e compred sttisticlly, the dt my indicte there were no negtive effects on htchility or progeny performnce for reeders fed LO-protein diets. Conclusion: At 0 weeks of ge, LI growth curve pullets were 5 g lighter in BW thn SD growth curve pullets nd cumultively consumed 7. kg/00 irds less feed from htched chick to 5% production. LI growth curve hens continued to consume less feed during production. From 5% production to weeks of ge, the cumultive feed consumed for the LI growth curve hens ws 6 to 8 kg/00 irds less thn SD rered hens. The LI growth curve rered hens lid. fewer eggs per hen thn SD growth curve rered hens (p = 0.085). Hens fed LO-protein (% CP) feed lid 0. more eggs per hen thn hens fed HI-protein feed (6% CP) (p = 0.78). Bsed on ingredient prices (My 0), feed cost per dozen eggs ws $.696 nd $.06 for hens fed HI-nd LO-protein reeder feed, respectively. Breeders fed the LO-protein diets consumed dily requirements of digestile mino cids s suggested y Ekmy et l. (0). Reserch reported y Ekmy et l. (0) indictes len mss increses in reeders fed nd 6 g per dy compred to reeders fed g. Incresing len mss nd incresing egg size y incresing dietry protein nd mino cids (s occurred in present study) would increse the dily requirement for energy. A reeder hen would either need to e fed more clories or ecome deficient in cloric intke to mintin her current egg mss production. ACKNOWLEDGMENTS The uthors would like to thnk Co-Vntress, Silom Springs, AR for finncil support, technicl support nd for providing irds nd feed for this reeder nd progeny feeding study. REFERENCES Avigen, 0. Aror Acres Plus Prent Stock Nutrition Specifictions. Avigen, Inc., Huntsville, AL Avigen, 0. Indin River Met Prent Stock Nutrition Specifictions. Avigen Inc. Huntsville, AL Avigen, 0c. Ross 08 Prent Stock Nutrition Specifictions. Avigen, Inc. Huntsville, AL Avigen, 0d. Ross 708 Prent Stock Nutrition Specifictions. Avigen, Inc. Huntsville, AL Avigen, 0. Ross PM Prent Stock Nutrition Specifictions. Avigen, Inc. Huntsville, AL Co-Vntress, 0. Breeder Mngement Guide. Co-Vntress Inc., Silom Springs, AR-776. Coon, C., M. De Beer, M. Mnngi, J. Lu, M. Reyes, K. Brmwell, J.M. Sun nd N. Skomur, 006. The mino cid nd crude protein requirements of roiler reeder hens for mintennce, production nd fertility. Proceedings for Arknss Nutrition Conference. Emssy Suite, Rogers, Arknss. De Beer, M. nd C.N. Coon, 006. The effect of incresed protein intke during the strter nd pre-reeder periods on reproductive performnce of ultr-high yield roiler reeder hens. Int. J. Poult. Sci., 5: 8-8. De Beer, M. nd C.N. Coon, 007. The effect of different feed restriction progrms on reproductive performnce, efficiency, frme size nd uniformity in roiler reeder hens. Poult. Sci., 86: De Beer, M. nd C.N. Coon, 009. The effect of feed restriction progrms nd growth curves on reproductive performnce, in vitro lipogenesis nd heterophil to lymphocyte rtios in roiler reeder hens. Int. J. Poult. Sci., 8: Ekmy, R.D., C. Sls, J. Englnd, S. Cerrte nd C.N. Coon, 0. The effects of pullet ody weight, dietry non-phytte phosphorus intke nd reeder feeding regimen on production performnce, chick qulity nd one remodeling in roiler reeders. Poult. Sci., 9: Ekmy, R.D., M. De Beer, S.J. Mei, M. Mnngi nd C.N. Coon, 0. Amino cid requirements of roiler reeders t pek production for egg mss, ody weight nd fertility. Poult. Sci., 9: Ekmy, R.D., C. Sls, J. Englnd, S. Cerrte nd C.N. Coon, 0. The effects of ge, energy nd protein intke on protein turnover nd the expression of proteolysis relted genes in the roiler reeder hen. Comp. Biochem. Physiol. B., 6: 8-. Ekmy, R.D., C. Sls, J. Englnd, S. Cerrte nd C.N. Coon, 0. Lysine prtitioning in roiler reeders is not ffected y energy or protein intke when fed t current industry levels. Poult. Sci., 9: Hrper, R.S., 008. Mesuring growth nd evluting reproductive performnce of commercil roilerreeder pullets fed on vrying growth curves. Mster s Thesis. Poultry Science Deprtment, University of Arknss, Fyetteville, AR-770. Hurd, 0. Hurd Clssic Mngement Guidelines. Prent Stock. Hurd LLC Wlpole, NH Hurd, 0. Hurd FLEX Mngement Guidelines. Prent Stock. Hurd LLC Wlpole, NH Hurd, 0c. Hurd JV Mngement Guidelines. Prent Stock. Hurd LLC Wlpole, NH Hurd, 0d. Hurd H Mngement Guidelines. Prent Stock. Hurd LLC Wlpole, NH

10 Int. J. Poult. Sci., (): , 0 Hudson, B.P., R.J. Lien nd J.B. Hess, 00. Effects of Roinson, F.E. nd N.A. Roinson, 99. ody weight uniformity nd pre-pek feeding progrms on roiler reeder hen performnce. J. Appl. Poult. Res., 0: -. JMP 8, 008. SAS Institute Inc. Joseph, N.S., F.E. Roinson, D.R. Korver nd R.A. Renem, 000. Effect of dietry protein intke during the pullet-to-reeder trnsition period on erly egg weight nd production in roiler reeders. Poult. Sci., 79: Joseph, N.S., A.A.J. Dulney, F.E. Roinson, R.A. Renem nd M.J. Zuidhof, 00. The effects of ge t photostimultion nd dietry protein intke on reproductive efficiency in three strins of roiler reeders vrying in rest yield. Poult. Sci., 8: Lilurn, M.S., K. Ngim-Rilling nd D.J. Myers-Miller, 989. Growth nd development of roiler reeders.. Independent effect of dietry formultion versus ody weight on skeletl nd muscle growth. Poult. Sci., 68: 7-8. Lopez, G. nd S. Leeson, 99. Response of older roiler reeders to medium-high intkes of J. Appl. Poult. Res., : Person, R.A. nd K.M. Herron, 98. Effects of mternl energy nd protein intkes on the incidence of mlformtions nd mlpositions of the emryo nd time of deth during incution. Br. Poult. Sci., : Petitte, J.N., R.O. Hwes nd R.W. Gerry, 98. The influence of flock uniformity on the reproductive performnce of roiler reeder hens housed in cges nd floor pens. Poult. Sci., 6: Renem, R.A., M.E. Rustd nd F.E. Roinson, 007. Implictions of chnges to commercil roiler nd roiler reeder ody weight trgets over the pst 0 yers. World s Poult. Sci. J., 6: Renem, R.A., F.E. Roinson nd M.J. Zuidhof, 007. Reproductive efficiency nd metolism of femle roiler reeders s ffected y genotype, feed lloction nd ge t photostimultion.. Sexul mturtion. Poult. Sci., 86: Reproductive performnce, growth rte nd ody composition of roiler reeder hens differing in ody weight t weeks of ge. Cn. J. Anim. Sci., 7: -. Roinson, F.E., R.A. Renem nd M.J. Zuidhof, 005. Current issues in mnging high-yield reeder hens. Proceedings of the Arknss Nutrition Conference. Roinson, F.E., M.J. Zuidhof nd R.A. Renem, 007. Reproductive efficiency nd metolism of femle roiler reeders s ffected y genotype, feed lloction nd ge t photostimultion.. Pullet growth nd development. Poult. Sci., 86: Sprtt, R.S. nd S. Leeson, 987. Broiler reeder performnce in response to diet protein nd energy. Poult. Sci., 66: Summers, J.D. nd S. Leeson, 99. Influence of diets vrying in nutrient density on the development nd reproductive performnce of white leghorn pullets. Poult. Sci., 7: Sun, J. nd C.N. Coon, 005. The effects of ody weight, dietry ft nd feed withdrwl rte on the performnce of roiler reeders. J. Appl. Poult. Res., : Wilson, H.R. nd R.H. Hrms, 98. Evlution of nutrient specifictions for roiler reeders. Poult. Sci., 6: Wilson, J.L., F.E. Roinson, N.A. Roinson nd R.T. Hrdin, 995. Effects of feed lloction on femle roiler reeders. J. Appl. Poult. Res., : 9-0. Zuidhof, M.J., R.A. Renem nd F.E. Roinson, 007. Reproductive efficiency nd metolism of femle roiler reeders s ffected y genotype, feed lloction nd ge t photostimultion.. Reproductive efficiency. Poult. Sci., 86: