Phylogenic versus selection effects on growth development, egg laying and egg quality in purebred laying hens

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1 1/ 16 Phylogeni versus seletion effets on growth evelopment, egg lying n egg qulity in purere lying hens Phylogenetishe un Selektionseffekte uf ie Whstumsentwiklung, Legeleistung un Eiqulität von Reinzuhtlegehennen M.-A. Lieolt 1, Ingri Hlle 1, Jn Frhm 1, L. Shrer 2, U. Bulin 3, Mrtin Henning 3, R. Preisinger 4, S. Dänike 1 n S. Weigen 3 1 Institute of Animl Nutrition, Frierih-Loeffler-Institut, Brunshweig, Germny 2 Institute of Animl Welfre n Animl Husnry, Frierih-Loeffler-Institut, Celle, Germny 3 Institute of Frm Animl Genetis, Frierih-Loeffler-Institut, Neustt-Mriensee, Germny 4 Lohmnn Tierzuht GmH, Cuxhven, Germny Corresponene: steffen.weigen@fli.un.e Mnusript reeive 12 Jnury 2015, epte 14 Mrh 2015 Introution Effiieny of poultry proution is ffete y severl ftors like fee osts, niml helth n welfre, n wie rnge of environmentl onitions (YALCIN et l., 2005; DARMANI KUHI et l., 2010). Min ojetives in reeing of lying hens re to hieve lrge numer of slele eggs, gret persisteny in lying performne, goo inner n outer egg qulity n low fee to egg mss rtio. In ition, efforts hve een me to improve helth n therefore welfre, n to gurntee goo pttion to ifferent kins of housing systems (PREISINGER, 2012). Due to effiient seletion the egg proution hs grown ynmilly, n the worl s nnul egg proution is estimte to e 1284 million (FAO, 2014). HORN n SÜTÖ (2000) emonstrte tht the reeing proess of the lst two ees of the 20 th entury improve the egg proution of white lyers y two eggs per yer. The poultry mrket of toy is ominte y only few reeing ompnies worlwie, wheres out 100 yers go nerly 40 hiken rees were use in reeing sttions in Germny (KNISPEL, 1908). Worl s egg onsumption is overe to 50% y white egg lyer hyris (HORN n SÜTÖ, 2000), whih hve een erive from one single ree, the White Leghorn (CRAWFORD, 1990). While iretionl geneti seletion is the mjor ontriutor to the hnges in performne potentil (HAVENSTEIN et l., 2003), it hs een reporte tht seletion for high proution effiieny in livestok speies is ssoite with unesirle sie-effets suh s efiienies in physiologil, immunologil n reproution trits s well s ehviorl prolems (DUNNINGTON, 1990; MILLER et l., 1992; LIU et l., 1995; RAUW et l., 1998). Suh unesirle sie-effets might e relte to n imlne in resoure llotion (GODDARD n BEILHARZ, 1977). Due to pttion of genotypes, the metoli resoures use y n niml shoul e optimlly istriute etween mintenne to ope with the environment in whih they re kept, n proution trits (BEILHARZ et l., 1993). As seletion ims t minimizing the metoli resoures not neee for mintenne, VAN DER WAAIJ (2004) n MIRKENA et l. (2010) hypothesize tht high performing genotypes hve reue pity to ompenste unexpete environmentl hnges like limite resoures ompre to low performing genotypes. To pproh this hypothesis we hve strte omprehensive ollortion t the Frierih-Loeffler-Institut to stuy the effet of seletion on performne effiieny towrs the ptility of lying hens uner vrying environmentl onitions in phylogeneti ontext. The esign of this ongoing reserh tivity is forme y four purere lyer lines iffering in performne level n phylogeneti origin (Fig. 1). Two high performing, ommeril genotypes (WLA n BLA) tken from reeing progrm of Lohmnn Tierzuht GmH re ontrste to two low performing ones (R11 n L68). R11 n L68 hiken lines re mintine s non-selete resoure popultions t the Institute of Frm Animl Genetis, Frierih-Loeffler-Institut, t Mriensee. The line R originte from the Cornell Line K (COLE n HUTT, 1973), n hs een introue to the Institute in the 1960 s (HARTMANN, 1987). Line L68 is New Hmpshire line, whih ws foune in the 1970 s in the former Germn Demorti Repuli (VEG Vogelsng). The two white lyer lines (WLA n R11) re of White Leghorn

2 2/ 16 origin n phylogenetilly losely relte, ut istnt from the Rhoe Isln Re higher performing line (BLA) n its low performing ounterprt L68 (LYIMO et l., 2014). Figure 1. Experimentl esign of purere lying hens iffering in performne level n phylogeneti reltionship Versuhsesign von Reinzuhtlegehennen untershielihen Leistungsniveus un phylogenetisher Verwntshft As first stuy, we report here on the hrteriztion of the experimentl moel of four hiken lines towrs the effets of phylogeny n seletion on growth n lying performne from hth to the en of the 74 th week of ge. Mteril n Methos Rering tril After hth totl of 516 one y-ol femle hiks were house over perio of 16 weeks in floor-rnge system. Due to iverging hth results of the ifferent genotypes (t not shown) the numer of house y-ol hiks vrie etween the four genotypes (140 hiks of WLA, 76 hiks of BLA, 147 hiks of R11 n 153 hiks of L68). Light ws provie for 24 hours on y 1 2. From y 3 onwrs light ws reue to 15 hours in the first week of ge. From week 1 to 7 light perio ws reue stepwise y one hour week to 9 hours n mintine until the en of rering (16 th week of ge). Temperture progrmme followe usul speifitions n the nimls were vinte ginst MD, ND n IB. After hth every hik ws equippe with n iniviul wing-tg, n genotypes were ple seprtely to single omprtment of floor-rnge system with nipple rinkers n feeing trough. During the whole tril fee n wter were provie liitum. Chiks were fe with ommeril grin-soyen mel iet (Tle 1) from week one to seven (pprox. 170 g rue protein n 11.5 MJ AME N /kg iet). From week eight to 16 growing pullets were lso fe with ommeril grin-soyen mel iet (pprox. 135 g rue protein n 11.3 MJ AME N /kg iet). Diets were formulte to meet nutrient requirements oring to the reommentions of the Ntionl Reserh Counil (NRC, 1994) n Soiety of Nutrition Physiology (GFE, 1999).

3 3/ 16 Tle 1. Composition, lulte n nlyze nutrient ontents of the experimentl iets. Zusmmensetzung, klkulierte un nlysierte Inhltsstoffe er Versuhsrtionen. Ingreients, g/kg iet Chiks (week 1 7) Pullets (week 8 16) Lyers (week 17 74) Corn Whet Brley Soyen mel Soyen oil Fiel Pes Luerne pellets Whet rn 22.0 Clium phosphte Clium ronte (limestone) Premix Premix Premix DL-methionine Soium hlorie Antioil (Sox 12%) 0.5 Chemil omposition, g/kg ry mtter Dry mtter ± ± ± 0.5 Crue sh ± ± ± 3.57 Crue protein ± ± ± 1.61 Crue ft ± ± ± 0.77 Crue fier ± ± ± 0.19 Neutrl etergent fier ± ± ± 8.70 Ai etergent fier ± ± ± 5.99 Strh ± ± ± 2.07 Surose ± ± ± 0.17 Phosphorous ± ± ± 0.21 Clium ± ± ± 0.81 AME N (MJ/kg DM) ± ± ± 0.05 Methionine Lysine premix hiks: fee itives (per kg premix): Vitmin A, 1,200,000 IU; Vitmin D 3, 350,000 IU; Vitmin E, 4,000 mg; Vitmin B 1, 250 mg; Vitmin B 2, 800 mg; Vitmin B 6, 600 mg; Vitmin B 12, 3,200 μg; Vitmin K 3, 450 mg; Niotin mie, 4,500 mg; Clium-D-pntothente, 1,500 mg; Foli i, 120 mg; Biotin, 5,000 μg; Choline hlorie, 55,000 mg; Fe, 3,200 mg; Cu, 1,200 mg; Mn, 10,000 mg; Zn, 8,000 mg; I, 160 mg; Se, 40 mg; Co, 20 mg; Butylte hyroxy toluene (BHT), 10,000 mg 2 premix pullets: fee itives (per kg premix): Vitmin A, 1,000,000 IU; Vitmin D 3, 200,000 IU; Vitmin E, 2,500 mg; Vitmin B 1, 250 mg; Vitmin B 2, 500 mg; Vitmin B 6, 400 mg; Vitmin B 12, 1,850 μg; Vitmin K 3, 300 mg; Niotin mie, mg; Clium-D-pntothente, 900 mg; Foli i, 80 mg; Biotin, 2,100 μg; Choline hlorie, 30,000 mg; Fe, 4,000 mg; Cu, 1,500 mg; Mn, 8,000 mg; Zn, 8,000 mg; I, 160 mg; Se, 32 mg; Co, 20 mg; Butylte hyroxy toluene (BHT), 10,000 mg 3 premix hens: fee itives (per kg premix): Vitmin A, 1,000,000 IU; Vitmin D 3, 250,000 IU; Vitmin E, 2,000 mg; Vitmin B 1, 250 mg; Vitmin B 2, 700 mg; Vitmin B 6, 400 mg; Vitmin B 12, 2,000 μg; Vitmin K 3, 400 mg; Niotin mie, 4,000 mg; Clium-D-pntothente, 1,000 mg; Foli i, 60 mg; Biotin, 2,500 μg; Choline hlorie, 40,000 mg; Fe, 4,000 mg; Cu, 1,000 mg; Mn, 10,000 mg; Zn, 8,000 mg; I, 120 mg; Se, 25 mg; Co, 20.5 mg; Butylte hyroxy toluene (BHT), 12,500 mg; Bet-rotene, 400 mg; Cnthxnthin, 400 mg 4 nlyze 5 pprent metolizle energy onentrtions orrete to zero nitrogen lne (AME N ), lulte oring to the energy estimtion eqution of the WPSA (VOGT, 1986) 6 lulte In the first hlf of the rering tril (hth to eighth week of ge) the nimls were weighe one week, while in the seon hlf (eighth to 16 th week of ge) they were weighe every seon week. Fee not onsume ws reore weekly. The ily weight gin n the fee to gin rtio were lulte.

4 4/ 16 Performne tril of lying hens At the en of the rering tril, week-ol pullets (48 of eh genotype) were move to lyer fility with single ges in three-floor ge system in rnom orer. Eh genotype ws llote to one experimentl group. The single ges enle iniviul reors of lying performne n fee intke. Eh ge (50 m 46 m 43 m) ws equippe with feeing trough, nipple rinker n perh. Fee n wter were provie liitum. From 17 th week of ge the light urtion ws inrese y hlf n hour per week to 14 hours of light t 23 r week of ge. After pre-lying perio from week 17 to 22, the performne tril ws suivie into thirteen 28-y lying perios. The tril ene t week 74. Hens were fe with ommeril grin-soyen mel iet (pprox. 150 g rue protein n 10.6 MJ AME N /kg iet; Tle 1). The iets were formulte to meet nutrient requirements oring to the NRC (1994) n GFE (1999) reommentions for high performing lying hens. Hens were weighe t the en of every 28-y lying perio. Eggs were reore ily. Defetive eggs (shell-less, rke, oule eggs) were lso reore. For eh lying perio the egg weight ws monitore y olleting ll li eggs of eh hen on three onseutive ys in two-week intervl. Fee not onsume ws reore weekly. Bse on the fee intke n egg mss the fee to egg mss rtio ws lulte. Egg qulity prmeters In the 40 th, 65 th n 74 th week of ge eggs of eh hen were ollete on three onseutive ys (40 th week: 416 eggs, 65 th week: 328 eggs, 74 th week: 250 eggs). Eggs were weighe n egg yolk n lumen were seprte. Weight of the shell, inluing the inner shell memrne, n weight of yolk were reore. The weight of lumen ws etermine y sutrting yolk n shell weight from the originl egg weight; yolk to lumen rtio ws lulte. Weights of the egg omponents re presente in perentge s proportions of the whole egg weight. Yolk olor ws estimte y using Rohe-fn (15 fns, F. Hoffmnn-L Rohe Lt., Bsel, Switzerln). Dry mtter n rue nutrients of fee Diets (Tle 1) were nlyze for ry mtter, rue sh, rue ft, rue fier, neutrl n i etergent fier, strh, surose, phosphorous, lium n Kjelhl N oring to the methos of the Assoition of Germn Agriulturl Anlyti n Reserh Institutes (VDLUFA; NAUMANN n BASSLER, 1993). Crue protein of the iets ws lulte y multiplying the Kjelhl N y The pprent metolizle energy onentrtions orrete to zero nitrogen lne (AME N ) of the iets were lulte oring to the energy estimtion eqution of the Worl s Poultry Siene Assoition (VOGT, 1986). Moelling of growth urves The time-epenent iniviully reore growth t (umultive growth; n = 48 per genotype) were fitte to the growth funtion of GOMPERTZ (1825) regressively from hth to the en of the 74 th week of ge. Tht t were nlyze y mens of the proeure nonliner regression of the softwre pkge Sttisti 10.0 for the Winows TM Operting System (STATSOFT INC., 2011). The metho of prmeter estimtion ws lulte using the itertive Qusi-Newton metho. Where y(t) = oy weight (g) of the hen t time t, expresse s funtion of ; = ult oy weight (g) of the hen (symptoti limit);, = prmeters of the funtion (regression oeffiients); n t = time (weeks) tken to reh the mximum rte of mturity. The ge t mximum oy weight gin (t mx ), tht is equivlent to the point of infletion of the umultive, sigmoi growth urve, ws lulte y the seon erivtive of the umultive growth funtion: The mximum ily weight gin ws ompute y sustituting the genotype speifi lulte t mx in the erivtive of the umultive growth funtion of the ssoite genotype.

5 5/ 16 Sttistil nlyses Sttistil nlysis of performne trits ws rrie out y mens of two ftoril nlysis of vrine (ANOVA) with genotype, ge n their intertion s fixe effets. For trits mesure repetely on the sme niml (e.g. oy weight, fee intke n egg weight) repete sttement ws onsiere in the sttistil moel to ount for similrities within sujets. Sttistil nlysis of lulte growth funtion prmeters ws rrie out y mens of one ftoril ANOVA with genotype s fixe effet. In oth ses the Tukey-Krmer test ws pplie for multiple omprison of mens. Dt were reporte s lest squre men vlues n stnr error. Differenes etween genotypes were onsiere to e sttistilly signifint for P < ANOVA of performne trits ws performe using the proeure MIXED n ANOVA of lulte growth funtion prmeters ws performe using proeure ANOVA of the softwre pkge SAS 9.2 (SAS INSTITUTE INC., 2010). Results Rering tril During the 16 weeks rering tril genotype, ge n their intertion ffete oy weight, ily weight gin, ily fee intke n fee to gin rtio signifintly (p 0.001; Tle 2). Tle 2. Growth performne of ifferent genotypes from hth to 16 th week of ge (LSMens; SEM; n = 140 (WLA), 76 (BLA), 147 (R11), 153 (L68)). Whstumsleistung vershieener Genotypen vom Shlupf is zur 16. Leenswohe. Boy Weight (g/hik) Dily Weight Gin (g/hik/) Dily Fee Intke (g/hik/) Fee to gin rtio (g/g) Genotype (GT) Hth WLA BLA R11 L SEM ,,, : LSMens within olumns with no ommon supersripts re signifintly ifferent (p < 0.05) Boy weight of ifferent genotypes showe time-epenent inrese (p 0.001) over the 16 weeks tril. The men hth weight (32 to 38 g/hik) i not iffer sttistilly etween the genotypes. After 16 weeks L68 hieve the highest oy weight (1249 g/hik) of the four genotypes (p < 0.05). The high performing BLA (1180 g/hik) n WLA (1107 g/hik) iffere signifintly from eh other, while R11 h the lowest oy weight (854 g/hik) fter 16 weeks. From week four onwrs L68 strte to iffer signifintly from the other genotypes n line R11 showe the lowest oy weight (p < 0.05). Until the en of the tril the high performing genotypes i not iffer from eh other. Aoring to the evelopment of oy weight, genotype lso signifintly influene ily weight gin (p 0.001; Tle 2). All genotypes showe highest ily weight gin t the tenth week of ge (p < 0.05). The highest weight gin of 14.5 g/hik/ ws reore in line L68 from week nine to twelve. In the first hlf of the tril line L68 iffere signifintly from the other genotypes n WLA n BLA i not iffer signifintly from eh other. During the entire rering R11 line hieve lowest ily weight gin of ll four lines. In the seon hlf oth rown lines i not iffer from eh other. Age lso ffete this trit high signifintly (p 0.001), s ily weight gin inrese until week 10, n then strongly erese to en of the tril. Dily fee intke lso showe time-epenent inrese (p 0.001; Tle 2) over the 16 weeks rering tril. In the first four weeks ll genotypes exluing R11 h similr ily fee intke. In the onseutive ourse, the rown genotypes

6 6/ 16 showe higher ily fee intke thn the white ones until 16 th week of ge (p < 0.05), in whih R11 hieve the signifintly lowest ily fee intke of ll four genotypes. Fee to gin rtio of the genotypes lso showe time-epenent inrese (p 0.001; Tle 2) over 16 weeks of rering. In the first eight weeks only L68 n WLA hieve signifintly lower fee to gin rtios thn R11. While no ifferenes etween genotypes ourre from the ninth to the twelfth week of ge, rown genotypes showe lower fee to gin rtios thn white ones in the lst four weeks (p < 0.001). Cumultive fee to gin rtio of genotypes ross the entire perio i not iffer. Apttion of growth t to the Gompertz funtion Non-liner regression of growth t fitte to the Gompertz funtion (GOMPERTZ, 1825) is summrize in Tle 3. Genotype ffete the eqution prmeters (, n ) s well s t mx n its ssoite mximum ily weight gin high signifintly (p 0.001). t mx ws hieve t 8.04 to 9.54 weeks of ge. WLA rehe mximum ily weight gin fter 8.04 weeks firstly (p < 0.05). In ontrst, BLA (9.25 weeks) n R11 (9.54 weeks) showe the slowest growth rtes (p < 0.05). R11 hieve the lowest n L68 the highest mximum ily weight gins t their speifi t mx (p 0.001), respetively. Tle 3. Influene of genotype on the prmeters of the Gompertz growth urve 1 from hth to 74 th week of ge n the ury of t fit (LSMens, SEM; n = 48 per genotype). Einfluss es Genotyps uf ie Prmeter er Gompertz-Whstumskurve 1 vom Shlupf is zur 74. Leenswohe sowie ie Genuigkeit er Dtennpssung. Genotype Estimte ult oy weight () [g] t mx RSD [weeks] R 2 (g) Estimte mximum DWG (g/hik/) Ahieve verge mximum DWG (g/hik/) WLA BLA R L SEM with y = oy weight t time t n the regression oeffiients (symptoti limit = ult oy weight), n t mx is equivlent to the point of infletion (time of mximum weight gin) R 2 = oeffiient of etermintion RSD = resiul stnr evition SEM = stnr error of men DWG = ily weight gin,,, : LSMens within olumns with no ommon supersripts re signifintly ifferent (p < 0.05) Growth urves n their erivtive, ientil to the ourse of ily weight gin, re presente in Figure 2 n 2. The symptoti limit of the urves, whih is equl to the estimte ult oy weight, emonstrte highly signifint (p 0.001) ifferenes etween rown n white genotypes, while L68 (1825 g) n BLA (1769 g) showe no sttistil ifferenes. In ontrst, the verge ult oy weight of white genotypes ws lulte to e 1512 g (WLA) n 1329 g (R11) whih iffere signifintly from eh other (p 0.001; Tle 3). The ourse of ily weight gin showe strong inrese until the genotype-speifi lulte t mx n strongly erese in the further ourse of the rering tril. After the 40 th week of ge, ily weight gin urves of the genotypes pprohe the orinte xis symptotilly.

7 7/ 16 Figure 2. Non-liner regression of growth t from hth to the 74 th week of ge of 48 purere lying hens of eh genotype fitte to the Gompertz eqution 1 () n the erive ourse of ily weight gin () with emphsis of the genotype speifi t mx Nihtlinere Regression er Whstumsten vom Shlupf is zur 74. Leenswohe von 48 Reinzuhtlegehennen jeen Genotyps ngepsst n ie Gompertz-Gleihung 1 () un er rus geleitete Verluf er täglihen Zunhmen () mit Hervorheung es Genotyp-spezifishen t mx Growth, fee intke n lying performne Growth evelopment n lying performne of the genotypes from the 23 r to the 74 th week of ge re summrize in Tle 4, ivie into four perios of 13 weeks eh, n were signifintly ffete y genotype, ge n their intertion (p 0.001). To otin etter overview, eh performne trit is shown over time in Figure 3-e.

8 8/ 16 Tle 4. Growth n lying performne of ifferent genotypes from 23 r to 74 th week of ge suivie in four perios of 13 weeks eh (I: week 23 35; II: week 36 48; III: week 49 61; IV: week 62 74) (LSMens, SEM; n = 48 per genotype). Whstums- un Legeleistung vershieener Genotypen von er 23. is zur 74. Leenswohe unterteilt in vier Perioen á 13 Wohen. Genotype (GT) Boy weight (g/hik) Fee intke (g/hen/) Lying intensity (%) Egg weight (g/egg) Egg mss (g/hen/) Fee to egg mss rtio (kg/kg) I II III IV I II III IV I II III IV I II III IV I II III IV I II III IV WLA BLA R L SEM ,,, : LSMens within olumns with no ommon supersripts re signifintly ifferent (p < 0.05) Figure 3. Time-epenent ourse of performne prmeters over 13 lying months (-e) s well s ge n oy weight t lying mturity (f) of the four genotypes uring the 13 lying months (LSMens ± SE; n = 48 of eh genotype). Zeithängiger Verluf er Leistungsprmeter üer 13 Legemonte (-e) sowie Alter un Leenmsse ei Legereife (f) er vier Genotypen Boy weight of the hens inrese signifintly with ge (p 0.001). During the whole tril, oth rown lyer lines were signifintly hevier thn oth white lyer lines (Tle 4, Figure 2). Within the rown genotypes L68 n within the white genotypes WLA weighe more thn their ounterprts. From week 23 to 74 rown genotypes gine more

9 9/ 16 thn 80 g oy weight. In low performing R11 oy weight even inrese y more thn 110 g/hen. Only the high performing WLA i not lter oy weight over the entire perio. During 13 lying months, ily fee intke (Tle 4, Figure 3) of the hens ws nerly onstnt, ut signifint ifferenes were oserve etween ll four genotypes (p < 0.05). The high performing ones h signifintly higher ily fee intke ompre to the low performing genotypes. Highest ily fee intke of 115 g/hen/ ws reore for BLA uring week 23 to 35. Therefter, ily fee intke of BLA erese slightly up to the en of the tril, n i not iffer from WLA fee intke t the en of the tril. During the entire tril WLA ingeste pproximtely 100 g/hen/, onstntly. The low performing genotypes iffere signifintly from eh other with onstnt ily fee intke of pproximtely 75 g/hen/ (R11) n 92 g/hen/ (L68). Lying mturity, efine s ge t the first egg li, ws firstly rehe y the hens of the high performing genotypes (Figure 3f). In omprison to the low performing genotypes, the high performing lines rehe lying mturity four to five weeks erlier, in the 20 th week of ge (p < 0.05). On rehing mturity ge, ll genotypes ut BLA (84%) weighe 90% of their ult oy weight (Figure 3f). Moreover, in the 364 ys of the lying tril the high performing genotypes hieve n verge numer of 310 (BLA) to 325 (WLA) eggs, while the low performing genotypes rehe 200 (R11) to 205 (L68) eggs. On verge, 1.4 ± 0.5% (WLA), 2.7 ± 0.5% (BLA), 1.6 ± 0.5% (R11) n 0.8 ± 0.5% (L68) of the eggs showe efets suh s shell-less, rkeroken n oule yolk eggs (p = ). Due to the ifferent ge t lying mturity, egg proution iffere signifintly t the eginning of the performne tril. In the first lying month high performing genotypes rehe n egg proution of more thn 85 to 90% (Figure 3), wheres the low performing hens showe n egg proution of pproximtely 20% (R11) n 37% (L68), respetively, t the sme time. All ut R11 genotypes rehe their mximum egg proution in the seon lying month. Hens of R11 rehe their mximum egg proution one month lter. The mximum egg proution of the high performing genotypes rnge from 93% (BLA) to 96% (WLA). Both low performing genotypes showe lower egg proution (p < 0.05) of mximl 67% (R11) n 74% (L68). In the following lying months egg proution slightly erese n persiste t pproximtely 75% in the high performing genotypes n 41 to 44% in the low performing genotypes until the en of the experiment. Results in Tle 4 showe tht the lying intensity of the high performing genotypes lrey strte to erese slightly fter week 23 to 35, while the lying intensity of low performing genotypes inrese until week 36 to 48 n erese onsierly therefter. Furthermore, the weight per egg (Figure 3e) rnge from pproximtely 40 g (R11, L68) to 50 g (WLA, BLA) t the eginning of the performne tril. In the following lying months egg weight slowly inrese in ll genotypes (p 0.001). At the en of the tril, the eggs weight rnge from 54.0 g (R11) to 61.0 g (WLA, BLA, n L68). Dily egg mss is illustrte in Figure 3. In the first lying month the low performing genotypes egn the tril with signifintly lower ily egg mss thn the high performing ones. Mximum ily egg mss proution ws hieve y R11 in the thir (31.4 g/hen/), WLA (52.5 g/hen/) n L68 (36.1 g/hen/) in the fourth n BLA (53.6 g/hen/) in the fifth lying month. To the en of the experiment, ily egg mss slowly erese to 44.4 to 45.3 g/hen/ in the high performing genotypes n to 22.2 to 27.4 g/hen/ in the low performing lyers. During the entire tril, high performing genotypes showe higher ily egg mss proution thn the low performing ones (p < 0.05) while no ifferenes were foun neither etween WLA n BLA nor etween R11 n L68. Due to the ifferent ge t lying mturity, fee to egg mss rtio (Figure 3) of the low performing genotypes (L68: 5.68; R11: 8.92) iffere signifintly from the one of the high performing hens (WLA: 2.19; BLA: 2.58) in the first lying month (Figure 3). From the seon lying month, fee to egg mss rtio showe nerly onstnt ourse. The four genotypes hieve their lowest level t the fourth to sixth lying month. In prtiulr, the high performing WLA rehe fee to egg mss rtio of less thn The high performing BLA hieve its lowest fee to egg mss rtio of Low performing genotypes showe signifintly higher fee to egg mss rtios of more thn At the en of the experiment the fee to egg mss rtio of ll genotypes slightly inrese. The high performing hens (2.30) iffere signifintly from the low performing hens (R11: 2.85, L68: 3.20). During the entire tril n verge mortlity of 8.9% ws reore. The losses for eh iniviul genotype re liste in the following sening orer: BLA 4.3% R11 8.3% L % n WLA 12.5%. Egg qulity t the 40th, 65th n 74th week of ge Totl egg weight, proportions of shell, yolk n lumen, the yolk olor n the lulte yolk to lumen rtio (Tle 5) were signifintly influene y genotype, ge n genotype ge (p 0.001).

10 10 / 16 Tle 5. Effet of genotype on egg qulity in the 40th, 65th n 74th week of ge 1. Effekt es Genotyps uf ie Eiqulität in er 40., 65. un 74. Leenswohe. Egg weight (g/egg) Shell (% of egg) Yolk (% of egg) Alumen (% of egg) Yolk to lumen rtio Yolk olour (Rohe fn) Genotype (GT) WLA BLA R L SEM Eh vlue represents the lest squre men of the li eggs of 48 hens on three onseutive ys eh of three replites,,, : LSMens within olumns with no ommon supersripts re signifintly ifferent (p < 0.05) In the 40 th week of ge, BLA eggs (59.6 g/egg) were signifintly hevier eggs thn those of other genotypes (WLA 55.3 g/egg; L g/egg; R g/egg). At the seon n thir exmintion te, eggs of ll genotypes h inrese their totl egg weight, s ge ffete the solute egg weight highly signifintly (p 0.001). At week 74, only R11 eggs (53.2 g/egg) iffere from those of other genotypes (58.9 to 59.6 g/egg; p < 0.05). In ontrst to the solute egg weight, WLA (13.6%) showe signifintly higher reltive proportion of egg shell in week 40 ompre to the other genotypes (BLA 12.9%; R %; L68: 11.9%). From week 40 to 74 the reltive proportion of egg shell erese signifintly in WLA, BLA n R11 (out 1.7 to 2.6% of totl egg weight; p 0.001), while the egg shell of L68 remine onstnt t 11.8% t lst exmintion te. Eggs of high performing genotypes (27.1 to 29.8%) showe signifintly lower proportions of yolk thn the eggs of the low performing ones (30.3 to 33.5%) t ll three exmintion times. Egg yolk proportion of high performing genotypes remine onstnt uring the tril, while the eggs of low performing genotypes showe slight inrese in yolk proportion (p 0.001). A reverse sitution ws foun in the lumen proportion. Eggs of WLA n BLA (57.1 to 62.4%) h signifintly higher lumen proportion thn those of R11 n L68 (55.3 to 57.4%). The lumen proportion of the high performing genotypes inrese y time (p 0.001), while eggs of R11 n L68 remine lrgely onstnt in this proportion t the three exmintion times. Purere lyers of the low performing genotypes showe signifintly higher yolk to lumen rtio thn the high performing genotypes. The yolk to lumen rtio of the low performing hens inrese y time, while tht of the high performing hens remine onstnt ross the three mesurement tes (p 0.001). Finlly, L68 eggs showe the most intensive yolk olor with 13.0 on the Rohe sle t the first exmintion time (p < 0.05). In ourse of the exmintion the time ffete the yolk olor (p 0.001), s the eggs of WLA, BLA n L68 hieve their most intensive oloring t week 65 (13.4 to 13.5), while the R11 yolks (12.6) h their most intensive olor t week 74. From the seon to the thir time of exmintion, yolk olor of WLA, BLA n L68 eline gin y 0.5 points on verge to pproximtely 13.0 on the Rohe sle. Disussion The ojetive of the present stuy ws to exmine the influene of ivergent genotypes on performne relte prmeters. The experimentl esign llows to ssess the effet of oth omponents seprtely, performne ivergene n phylogeneti ivergene. Phylogeneti reltionship etween white lyers n rown lyers were esrie previously (GRANEVITZE et l., 2009; LYIMO et l., 2014).

11 11 / 16 Signifint ifferenes were foun in the four genotypes stuie onerning severl performne prmeters. In orne with PREISINGER (2000), results of this stuy onfirme tht rown lyer genotypes h higher oy weight thn white lyers. Higher oy weight went long with signifintly higher fee intke in rown genotypes in ontrst to their white ounterprts, resulting from n solutely higher mintenne requirement of rown lyers (PREISINGER, 2000). Beuse of ientil onitions in feeing n housing, ifferenes in ily fee intke n lying performne re likely to result from the genetilly etermine performne potentil of the stuie genotypes. Besies the signifint ifferenes etween high n low performing genotypes in severl lying performne trits, lso ge t onset of lying ws signifintly ifferent etween the high n low performing genotypes. Lying mturity is n importnt trit whih is ffete y seletion n hs gret importne to the life output of lying hens (POGGENPOEL n DUCKITT, 1988). WLA n BLA in this tril rehe lying mturity four to five weeks erlier thn the low performing genotypes. As esrie y POGGENPOEL n DUCKITT (1988) the intensive seletion on egg proution ws losely onnete with the intensive seletion on sexul mturity. This fits well to the finings of HORN n SÜTÖ (2000) tht toy s lyers strt to ly out 15 to 20 ys erlier thn 20 yers go. Furthermore, these uthors reporte tht the oy weight of white lyers remin onstnt, while the egg weight n the totl egg mss inrese. In se of oy weight, the high performing rown lyers (BLA) showe signifintly lower oy weight thn the low performing ones fter four weeks of rering. This signifint ifferene remine until the en of the lying performne tril in the 74 th week of ge. Within the high performne level the white lyers (WLA) showe signifintly lower oy weight thn BLA. This irumstne is lso well epite y the lulte growth urves in our stuy. The Gompertz eqution is frequently use in poultry (GOUS et l., 1999; SAKOMURA et l., 2005). Boy weight t of ll four genotypes were pte to the Gompertz eqution n its erivtive, n showe goo fit to the hosen moel with R 2 rnging from (R11) to (WLA). As result, this growth eqution (Figure 2, Tle 3) oul e useful for further experiments uner hnging environmentl onitions to etermine the effiieny of nutrient utiliztion, or to preit ily energy, protein n minerl requirements (DARMANI KUHI et l., 2010) of the genotypes stuie. Signifint ifferenes were oserve mong the genotypes for severl urve prmeters, espeilly the ge t mximum ily weight gin (t mx ). In ontrst to BLA, WLA hieve the mximum weight gin first n rehe, s well s R11 n L68, 90% of its ult oy weight t ge of lying mturity. These finings emphsize the fst evelopment of high performing White Leghorn lyers regring their oy weight. Intensive seletion on erly sexul mturity reue the ge t first egg (POGGENPOEL n DUCKITT, 1988) n ge t rehing the symptoti oy weight (SZYDLOWSKI n SZWACZKOWSKI, 2001). In ition to the lying performne, egg qulity ws nlyze. It shows tht genotype, ge n their intertion h highly signifint influene on the evlute prmeters. Aoring to the finings of severl other uthors (HEIL n HARTMANN, 1997; LEDVINKA et l., 2000; VITS et l., 2005), in week 40 n week 65 the exmine eggs of rown hens were hevier thn those of white hens, while t week 74, ifferenes etween BLA, L68 n WLA were no longer sttistilly etetle. In greement with RIZZI n CHIERICATO (2005) n JOHNSTON n GOUS (2007), the solute egg weight inrese with the ge of the hens in the stuie genotypes. Conerning the effet of ge on egg proportions, there re ontriting finings reporte in the literture (ROSSI n POMPEI, 1995; SUK n PARK, 2001; SILVERSIDES n SCOTT, 2001; YANNAKOPOULOS et l., 1994). In our stuy, eggs of high performing hens showe eresing proportion of shell n yolk with ge, ut inresing proportion of lumen. In omprison, eggs of low performing hens erese in proportion of egg shell, ut inrese for egg yolk, n remine onstnt in lumen ontent. Besie the time-epenent effet n the ifferenes etween high n low performing genotypes on egg qulity, severl uthors me sttements out the effets of phylogeny. LEYENDECKER et l. (2001) foun signifintly higher yolk proportions in white eggs thn in those of rown lyers. Our results inite tht the eggs of high performing rown lyers h lower yolk proportions thn those of the high performing white lyers. In se of the low performing genotypes, however n opposite reltion ws foun etween white n rown lyers. Furthermore, the white hens of present stuy showe signifintly higher egg shell proportion thn rown hens. The finings of LEDVINKA et l. (2000) ontrit our results, while BASMACIOGLU n ERGUL (2005) foun no signifint effet of genotype on shell perentge y ompring Bok-300 (white lyers) with Is-Brown (rown lyers). This suggeste tht generl sttements out egg qulity prmeter without onsiertion of the stuie genotype shoul not e me, s geneti influene on egg qulity prmeters is very strong (BUSS n GUYER, 1982; STEINHILBER, 2005; FLOCK et l., 2007).

12 12 / 16 In ition to egg qulity, proportion of efet eggs ws reore. In ontrst to WOLC et l. (2012), the present stuy i not onfirm the ssumption tht high prouing hens h lower frequeny of egg efets in generl. The lowest proportion of efet eggs ws oserve in low performing rown hens. While there ws hrly ny ifferene etween white hens of WLA (1.4%) n R11 (1.6%), proportion of efet eggs iffere mrkely etween rown hens of L68 (0.8%) n BLA (2.7%). Genotypes of sme performne level n with istnt phylogeneti reltionship (WLA/BLA n R11/L68) showe similrities in severl trits with ifferenes less thn five perentge. Other trits iffere signifintly etween five n ten perentge in high performing genotypes (e.g. egg yolk proportion, ily fee intke n fee to egg mss rtio) n etween 20 n 40 perentge in low performing genotypes (e.g. oy weight, ily fee intke, egg weight n ily egg mss). Consiering the phylogeneti reltionship (WLA/R11 n BLA/L68), ifferenes of out 30 to 100 perentge oul e foun in performne relte trits. However, ifferenes in egg qulity prmeters were muh lower (four to nine perentge) etween losely relte strins. Conlusions The results of this stuy fitte well with the intene performne ivergene etween high n low performing genotypes in the estlishe experimentl esign (Fig. 1). Firstly, reore t of ily fee intke, growth n lying performne uner onitions of ientil feeing n housing gve n initil impression of the performne potentil of the stuie genotypes. Seonly, suh t oul e use to lulte performne-epenent nutrient requirements of the four genotypes in further experiments. In those stuies the genotypes shoul e stresse y hnging environmentl onitions (e.g. vi nutrition, infetious iseses, hllenging housing onitions) n their physiologil retions oul e stuie onerning the pttion ility to suh new onitions. Aknowlegements The uthors grtefully knowlege Silvi Wittig, Ines Weinholz n Gi Orlowski for their prtiiption t the re of the experimentl nimls, the smple n t olletion n the prtil reliztion of the experiments. Furthermore, the uthors knowlege Annerose Junghns for her prtiiption t the smple preprtion. Summry The im of the present stuy ws to ssess the performne trits of hiken lines with ifferent performne level n phylogeneti origin. Seletion for high performnes my hnge unselete trits relte to niml helth n welleing. However, long efore intense seletion strte to t leing to ontemporry high performing genotypes, founer popultions on egg lying rees with white n rown egg shell h een seprte for mny genertions n hve evolve inepenently. We hve strte to set up omprehensive ollortive effort t the Frierih-Loeffler- Institut to pproh reserh question relte to the pity of high selete hiken lines to ope with limite metoli resoures. As first step, four genotypes of purere lying hens (WLA, BLA, R11 n L68) were use, whih were ivie y their ivergene in performne n phylogeny. For the first time these genotypes were hrterize oring to their performne n growth evelopment in the first 16 weeks of ge in rering tril, pre-lying perio of 6 weeks n following performne tril of 13 lying months (23 r to 74 th week of ge). The investigte performne trits were signifintly ffete y genotype, ge n their intertion (p 0.001). As result of seletion for high lying performne, selete strins showe signifintly higher performne thn the non-selete ones. The high performing genotypes h n verge lying intensity of 85 to 90%, ily egg mss proution of pproximtely 50 g/hen/ n fee to egg mss rtio of 2.1 to 2.3 kg/kg. However, the low performing genotypes h n verge lying intensity of 52 to 56%, ily egg mss proution of pproximtely 26 to 31 g/hen/ n fee to egg mss rtio of pproximtely 3.0 kg/kg. Conerning verge egg weight only R11 (50 g/egg) iffere from the other experimentl lines (55 to 58 g/egg). Inepenently of their performne rown hens showe signifintly higher oy weight thn white hens uring the whole tril. Egg qulity nlyses showe tht high performing lines h signifintly higher lumen proportion (57.1 to 62.4%) n signifintly lower yolk proportion (26.8 to 29.8%) thn the low performing lines (lumen: 55.3 to 57.4%, yolk: 30.3 to 33.5%). White hens (10.8 to 13.6%) h signifintly higher proportion of egg shells thn rown hens (10.3 to 12.9%).

13 13 / 16 In summry, the stuie genotypes showe ler ifferenes in performne level tht me them well suitle for the estlishe experimentl esign. With tht esign further stuies shoul e rrie out uner vrying environmentl onitions (e.g. feeing, housing, infetious iseses). Therey the stuies will exmine the question whether seletion on high performne (WLA, BLA) les to reue ptility to vrying environmentl onitions. Key wors Experimentl esign, hiks, pullets, lying hens, genotypes, growth, lying performne, egg qulity, Gompertz eqution Zusmmenfssung Phylogenetishe un Selektionseffekte uf ie Whstumsentwiklung, Legeleistung un Eiqulität von Reinzuhtlegehennen Ds Ziel er vorliegenen Untersuhung wr ie Entwiklung eines Versuhsesign zur Beurteilung von Leistungsmerkmlen ei Hühnerlinien untershieliher Leistungsniveus un phylogenetisher Herkunft. Selektion uf hohe Leistung könnte niht-selektierte Eigenshften ezüglih Tiergesunheit un Wohlefinen veränern. Lnge evor eine intensive Selektion zu en gegenwärtigen hohleistenen Genotypen hin urhgeführt wure, trennte mn Grünerpopultionen von Legezuhten mit weißer un runer Eishle für mehrere Genertionen, ie sih rufhin unhängig voneinner entwikelten. Dher hen wir eine umfngreihe Zusmmenreit m Frierih-Loeffler-Institut egonnen, um uns Forshungsfrgen zu nähern, ie sih mit er Leistungsfähigkeit strk selektierter Hühnerlinien im Umgng mit egrenzten metolishen Ressouren efssen. Als erster Shritt wuren vier Genotypen von Reinzuhtlegehennen (WLA, BLA, R11 un L68) usgewählt, ie hinsihtlih ihrer Divergenz in Leistung un Phylogenie unterteilt wuren. Zum ersten Ml wuren iese Genotypen ezüglih ihrer Leistung un Whstumsentwiklung in en ersten 16 Leenswohen in einem Aufzuhtversuh, einer sehswöhigen Vorlegephse un einem ngeshlossenen Leistungsversuh üer 13 Legemonten ( Leenswohe) hrkterisiert. Die untersuhten Leistungsmerkmle wuren urh en Genotyp, s Alter sowie eren Interktion höhst signifiknt eeinflusst (p 0.001). Als Folge er Selektion uf hohe Legeleistung zeigten selektierte Linien eine signifiknt höhere Leistung ls Nihtselektierte. Die hohleistenen Genotypen htten eine Legeintensität von urhshnittlih 85 is 90%, eine täglihe Eimsseprouktion von. 50 g/henne/ sowie eine Futterverwertung von 2.1 is 2.3 kg/kg. Die minerleistenen Genotypen htten hingegen eine Legeintensität von urhshnittlih 52 is 56%, eine täglihe Eimsseprouktion von 26 is 31 g/henne/ sowie eine Futterverwertung von. 3.0 kg/kg. Hinsihtlih es urhshnittlihen Eigewihtes untershie sih leiglih R11 mit 50 g/ei von en ürigen Versuhslinien mit 55 is 58 g/ei. Unhängig von ihrer Leistung zeigten rune Hennen üer en gesmten Versuh eine signifiknt höhere Leenmsse ls weiße Hennen. Untersuhungen er Eiqulität zeigten, ss hohleistene Linien einen signifiknt höheren Eiklrnteil (57.1 is 62.4%), gleihzeitig er einen signifiknt nierigeren Eiotternteil (26.8 is 29.8%) ufwiesen ls minerleistene Linien (Eiklr: 55.3 is 57.4%, Dotter: 30.3 is 33.5%). Weiße Hennen (10.8 is 13.6%) esßen einen signifiknt höheren Shlennteil ls rune Linien (10.3 is 12.9%). Zusmmenfssen zeigten ie untersuhten Genotypen eutlihe Untershiee hinsihtlih es Leistungsniveus, welhe sie für s etlierte Versuhsesign sehr gut geeignet mhen. Mit iesem Design sollen weitere Stuien unter vriierenen Umwelteingungen (z.b. Fütterung, Hltung, Infektionen) urhgeführt weren. Dei soll er Frge näher nhgegngen weren, o eine Selektion uf hohe Leistung (WLA, BLA) zu einer verminerten Anpssungsfähigkeit n vriierene Umwelteingungen führt. Stihworte Versuhsesign, Küken, Junghennen, Legehennen, Genotypen, Whstum, Legeleistung, Eiqulität, Gompertz- Funktion

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16 16 / 16 VITS, A., D. WEITZENBURGER, H. HARTMANN, O. DISTL, 2005: Proution, egg qulity, one strength, lw length, n keel one eformites of lying hens house in furnishe ges with ifferent group size. Poult. Si. 84, VOGT, H., 1986: WPSA energy estimtion formul. Working group No. 2 Nutrition of the Europen Feertion of WPSA. Report of the Meeting. Worl s Poult. Si. J. 42, WOLC, A., J. ARANGO, P. SETTAR, N.P. O SULLIVAN, V.E. OLORI, I.M.S. WHITE, W.G. HILL, J.C.M. DEKKERS, 2012: Geneti prmeters of egg efets n egg qulity in lyer hikens. Poult. Si. 91, YALCIN, S., S. OZKAN, M. CABUK, J. BUYSE, E. DECUYPERE, P.B. SIEGELS, 2005: Pre- n post-ntl onitioning inue thermotolerne on oy weight, physiologil responses, n reltive symmetry of roilers originting from young n ol reeer floks. Poult. Si. 84, YANNAKOPOULOS, A.L., A.S. TSERVENI-GOUSI, P. NIKOKYRIS, 1994: Egg omposition s influene y time of oviposition, egg weight, n ge of hens. Arh. Geflügelk. 58, Corresponene: Dr. Steffen Weigen, Institut für Nutztiergenetik, Bunesforshungsinstitut für Tiergesunheit, Frierih-Loeffler-Institut, Höltystrße 10, Neustt-Mriensee, Germny: Emil: steffen.weigen@fli.un.e