Interntionl Journl of Poultry Science 6 (6): 434-439, 2007 ISSN 1682-8356 Asin Network for Scientific Informtion, 2007 Effects of Genotype nd Housing System on the Lying Performnce of Chickens in Different Sesons in the Semi-Humid Tropics 1 2 3 A. Ykuu, A.E. Slko nd A.O. Ige 1 Deprtment of Animl Science, Nsrw Stte University, Keffi, Shu-Lfi Cmpus, P.M.B. 135, Lfi, Nigeri Deprtment of Animl Science, University of Idn, Idn, Nigeri 3 Deprtment of Animl Production nd Helth, Ldoke, Akintol University of Technology, Ogomoso, Nigeri 2 Astrct: An experiment ws designed to study the effects of genotype nd housing system on the performnce of two commercil lyers, Bovns Brown nd Lohmnn Brown in the hot-dry nd wet sesons in Lfi, Nsrw Stte, Nigeri. Six hundred, 27 week-old lyers were used. One hundred nd fifty irds of ech strin were rndomly ssigned to the ttery cge system, while nother one hundred nd fifty irds of ech strin were mnged on deep litter. The oservtion for the hot-dry nd wet sesons lsted 2 months ech respectively in the yer 2004. Body weight, hen-housed egg production, egg weight nd mortlity rte were significntly etter in Lohmnn Brown thn Bovns Brown (1.75±0.01kg vs. 1.69±0.01kg, 74.50±0.84% vs. 68.72±0.86%, 53.70±0.24g vs. 52.43±0.26g, 0.58±0.09% vs. 1.20±0.15%; p<0.05). Birds in cges were superior to those on deep litter in terms of hen-housed egg production, egg weight nd mortlity (74.06±0.75% vs. 69.16±1.02%, 53.40±0.24g vs. 52.73±0.29g, 0.68±0.10% vs. 1.10±0.15%; p<0.05). Generlly, irds performed etter in the wet thn hot-dry seson in ody weight, hen-housed egg production, feed intke, egg weight, egg crcks nd mortlity (1.76±0.01kg vs. 1.68±0.01kg, 74.92±0.74% vs. 68.30±0.86%, 98.51±0.50g vs. 90.90±0.23g, 53.92±0.18g vs. 52.22±0.27g, 1.99±0.23% vs.5.12±0.39%, 0.55±0.08% vs. 1.22±0.15%; p<0.05). The interctions etween genotype housing system, genotype seson nd housing system seson produced significnt results. Proper housing design, provision of qulity nd dequte feeds nd proper timing of the lying period were recommended. Key words: Exotic strins, mngement system, seson, performnce prmeters, interction Introduction significntly ffected the ody weights of irds, while egg The performnce of lying hens kept in the tropics is production, egg weight, feed consumption nd efficiency, determined to lrge extent y the irds productive shell thickness nd livility were not significntly dptility. A high level performnce, no dout, is the influenced (Akinokun nd Benyi, 1985). im of ny enterprise involved in the production of eggs. Environmentl fctors such s temperture nd humidity Genetic vrition in egg production etween reeds, lso ffect gretly the lying performnce of fowls strins nd lines hs een reported (Nwr nd Adou, (Kssim et l., 1984; Hzn, 1984). The Nigerin 1999; Suk nd Prk, 2001; Hocking et l., 2003). On the climtic environment is chrcterised y high other hnd, the productivity of exotic strins intensively temperture nd reltive humidity typicl of tropicl rered is high compred with the ntive hens (Ershd, regions. This tends to ffect negtively the physiologicl 2005). The influence of housing system on productivity trits functions of irds (Dud et l., 2006). The temperture hs een studied. Comprison of results of egg zone in which the performnce of dult fowl is not production rte, egg weight, feed efficiency (feed/dozen dversely ffected y temperture is 12.8-26 C (Oluyemi eggs) nd ly house mortlity of lyers showed the nd Roerts, 2000). Ikhimioy nd Arijeniw (1998) superiority of cge over deep litter housing system oserved tht the verge performnce of lyers ws (Ayorinde et l., 1999). Muthusmy nd Viswnthn etter in the wet seson for hen-housed egg production, (1998) lso found higher egg lying performnce of men dily, weekly egg production nd egg weight hens in cges thn those kept on floor. According to compred with the dry seson. Similrly, low egg Suto et l. (1997), housing systems influenced the henhoused egg production, correlted egg mss production hs een documented (Bnnor nd Ogunsn, 1987). production nd high mortlity rte in the hot-dry seson nd dily feed consumption. In his own findings, Awoniyi According to Al-Rwi nd Aou-Ashour (1983), feed (2003) reported tht the productivity of lyer-chickens in intke, egg production nd ody weight declined with the different tiers of 3-tier cges vried. Housing system increse in temperture. 434
Tle 1: Men monthly vlues for environmentl temperture, reltive humidity nd rinfll of Lfi during the study period Mx. Min. Reltive Rinfll temp. temp. humidity (mm) Month ( C) ( C) (%) Jnury 36.2 18.5 46.4 0.0 Ferury 37.6 22.1 NA 0.0 Mrch 38.8 24.4 41.6 1.0 April 35.2 25.4 66.3 56.8 My 33.5 23.1 NA 124.3 June 31.1 22.2 NA 373.3 July 29.7 22.7 85.1 213.7 NA : Not ville, Source: Nigerin Meteorologicl Agency (NIMET), Lfi, Nsrw Stte, (2004) Tle 2: Effect of genotype on the lying performnce of hens Genotype --------------------------------------- Bovns Lohmnn Prmeters Brown Brown Averge weekly ody weight (kg) 1.69±0.01 1.75±0.01 Hen-housed egg production (%) 68.72±0.86 74.50±0.84 Feed intke (g/ird/dy) 95.46±0.78 93.96±0.77 Egg weight (g) 52.43±0.26 53.70±0.24 Averge weekly egg crcks (%) 3.69±0.45 3.42±0.39 Averge weekly mortlity (%) 1.20±0.15 0.58±0.09 Mens within rows designted y different superscripts differ significntly (p<0.05) A review of ville literture reveled tht studies on the lying performnce of exotic strins in the semihumid tropics re inconclusive. Therefore, the present study ws conducted to investigte the influence of genotype nd housing system on egg production performnce of chickens in different sesons under tropicl conditions of north centrl Nigeri. Mterils nd Methods Study loction: The study ws conducted in commercil poultry frm in Lfi, the cpitl of Nsrw Stte, which is in the Northern Guine o Svnn zone of Nigeri. It lies within ltitude 8 30' N o nd longitude 834' E. It hs two succinct climtic sesons; the wet seson strts from My nd ends in Octoer, while the dry seson strts from Novemer to April. Experimentl irds nd mngement: The experimentl irds were 600 selected pullets of Bovns Brown nd Lohmnn Brown (commercil lying stock) rered from dy-old. At 27 week-old, 150 irds of ech strin were rndomly ssigned to the ttery cge housing system, while nother 150 irds of ech strin were similrly housed on deep litter. A two-tier cge ws used in n open-sided uilding. The dimension of ech cge which housed 2 irds ws 0.38m 0.33m. Ech strin ws divided into three groups of fifty irds ech, while the dimension of the deep litter housing ech group ws 2.20m 2.00m. Proper snittion ws crried out in the irds houses, while they were lso routinely vccinted ginst infectious diseses. All irds were fed pelletized commercil lyer s feed contining 16.50% crude protein; 2550 kcl/kg metolizle energy; 4.00% ft; 4.60% crude fire; 3.70% clcium nd 0.41% ville phosphorus. Fresh nd clen wter ws lso supplied d liitum. The investigtion for the hot-dry seson lsted from Mrch to April, 2004 while tht of the wet seson lsted from June to July, 2004. The verge monthly temperture, reltive humidity nd rinfll of Lfi during the study period re presented in Tle 1. Dt collection: Dt on verge weekly ody weight (kg), hen-housed egg production (%), feed intke (g/ird/dy), egg weight (g), verge weekly egg crcks (%) nd verge weekly mortlity (%) were tken. Egg collection ws done t 0800, 1100 nd 1700 hours ech dy. Feed intke ws estimted y the difference in the mount offered nd the leftover collected the following dy. Individul eggs were weighed. Dt nlysis: Dt collected were sujected to nlysis of vrince using the PROC MEANS procedure of SAS (1999) pckge. The sttisticl model employed ws: Y = µ + G + H + S + (GH) + (GS) + (HS) + e ijk i j k ij ik jk ijk Where, Y ijk = individul oservtion µ = popultion men G i = effect of the ith genotype (I = Bovns Brown, Lohmnn Brown) H j = effect of the jth housing system (j = Bttery cge, Deep litter) S k = effect of the kth seson (Hot-dry, wet) (GH) ij = effect of the interction of the ith genotype nd jth housing system (GS) ik = effect of the interction of the ith genotype nd kth seson (HS) jk = effect of the interction of the jth housing system nd kth seson. e ijk = rndom residul error normlly nd independently distriuted with zero men nd common vrince. Men seprtion ws effected using lest significnce difference (LSD) method nd tested t p<0.05. Results nd Discussion Effect of genotype: Tle 2 shows the men ody weight, hen-housed egg production, feed intke, egg weight, egg crcks nd mortlity. Genotype hd significnt (p<0.05) effects on the performnce trits 435
Tle 3: Effect of housing system on the lying performnce of hens Housing System --------------------------------------- Prmeters Bttery Cge Deep litter Averge weekly ody weight (kg) 1.73±0.01 1.72±0.01 Hen-housed egg production (%) 74.06±0.75 69.16±1.02 Feed intke (g/ird/dy) 93.79±0.70 95.62±0.83 Egg weight (g) 53.40±0.24 52.73±0.29 Averge weekly egg crcks (%) 3.68±0.44 3.43±0.40 Averge weekly mortlity (%) 0.68±0.10 1.10±0.15 Mens within rows designted y different superscripts differ significntly (p<0.05) Tle 4: Effect of seson on the lying performnce of hens Seson --------------------------------------- Prmeters Hot-dry Wet Averge weekly ody weight (kg) 1.68±0.01 1.76±0.01 Hen-housed egg production 68.30±0.86 74.92±0.74 Feed intke (g/ird/dy) 90.90±0.23 98.51±0.50 Egg weight (g) 52.22±0.27 53.92±0.18 Averge weekly egg crcks (%) 5.12±0.39 1.99±0.23 Averge weekly mortlity (%) 1.22±0.15 0.55±0.08 Mens within rows designted y different superscripts differ significntly (p<0.05) studied with the exception of egg crcks. Lohmnn Brown hens hd significntly higher ody weight, henhoused egg production nd egg weight compred with Bovns Brown. Feed intke nd percentge mortlity were higher in Bovns Brown thn Lohmnn Brown. Vrile egg production performnce for vrious strins of chicken hd een reported (Tolimir nd Msic, 2000). According to Ershd (2005), rown shelled hyrid lyers were etter thn their white shelled counterprts in terms of ody weight. The findings of Akinokun nd Benyi (1985) indicted tht genotype hd significnt effects on ody weight trits. A reltionship ws lso estlished etween the production prmeters. Egg weight nd feed intke were correlted with ody weight s oserved in Lohmnn Brown. Mjro (2001) reported the superiority of Lohmnn Brown over Hrco lyers in egg production during feed restriction. This ws inconsistent with the findings of Duduyemi (2005) tht there ws no significnt difference etween Bovns Brown nd Bovns Ner in egg production. It ws ttriuted to the fct tht the exotic irds were commercil hyrids tht hve een selected over mny genertions from interreeding etween specilized reeds, lines or strins. Although feed intke ws higher in Bovns Brown, it did not reflect in the ody weight, hen-housed egg production nd egg weight. This is n indiction of etter feed utiliztion y their Lohmnn Brown counterprts which impcted positively on productivity trits. The lower mortlity rte of Lohmnn Brown lso indicted etter dpttion to the previling environmentl conditions compred to Bovns Brown. Effect of housing system: A summry of the mens of the different performnce chrcteristics in the ttery cge nd deep litter housing systems re presented in Tle 3. Hen-housed egg production, feed intke, egg weight nd mortlity were significntly (p<0.05) influenced. No significnt difference (p>0.05) ws oserved for ody weight nd egg crcks respectively. Birds in the ttery cge hd significntly higher henhoused egg production nd egg weight compred with those on deep litter. Feed intke ws higher mong irds on deep litter while mortlity ws lower mong those in cges. Lying hens differ in their dptility to different husndry systems. Results of the present study re in consonnce with some of the erlier investigtions tht irds in cges ly more eggs thn those on deep litter (Suto et l., 1997; Ayorinde et l., 1999; Flock et l., 2005). The higher egg rte in the cge is ttriutle to etter rering environment. According to Tuson et l. (1999), cged irds performed etter ecuse they were reltively gurded ginst ir pollution nd pthogenic orgnisms. This my lso e indictive of the fct tht hens were more efficient in feed conversion; nd there ws lesser incidence of feed wstge. The higher egg weight in the cge system compred with the deep litter system is consistent with the findings of Suto et l. (1999). However, the present result otined did not conform with tht oserved y Akinokun nd Benyi (1985), where housing system hd no significnt effect on egg weight. It lso disgreed with the findings of Al- Rwi nd Aou-Ashour (1983) tht floored hens were superior to cged irds in egg weight. Plne of nutrition is known to ffect productivity trits. Birds on deep litter consumed more feed thn their counterprts in cges, lthough there ws no reflection on hen-housed egg production nd egg weight. This could e ttriuted to greter moility of the irds therey resulting in more energy utiliztion t the expense of production. Extr energy could lso e required for mintennce t low mient temperture or when fether cover is poor (Scientific Veterinry Committee, 1996). The present result on mortlity is in conformity with tht reported y Ayorinde et l. (1999) in NAPRI commercil lyers. It lso corroortes the oservtions of Al-Rwi nd Aou- Ashour (1983) tht housing system exerted no significnt influence on ody weight. The non-significnt difference in egg crcks etween the housing systems disgreed with the findings of Adeyemi et l. (2002) nd Frooq et l. (2002) where higher incidence of crcked eggs ws recorded in floor-rered lying hens thn those kept in cges. The present findings re ttriutle to the dequte clcium content of the experimentl diet nd frequent egg collection. According to Moreki et l. (2005), 2.5% level of dietry clcium ws sufficient to sustin sound eggshell qulity. 436
Tle 5: Effect of Genotype x housing system interction on egg production performnce of lyers Performnce Prmeters ------------------------------------------------------------------------------------------------------------------------------------------- Averge Hen-housed Averge Housing weekly egg Egg weekly Averge system Body production Feed intke weight Egg weekly Genotype (%) weight (kg) (%) (g/ird/dy) (g) crcks (%) Mortlity Bovns Bttery cge 1.70 71.63 94.87 52.76 3.56 0.89 Brown Deep litter 1.68 65.82 96.04 52.11 3.82 1.51 Lohmnn Bttery cge 1.76 76.50 92.71 54.05 3.80 0.46 Brown Deep litter 1.75 72.51 95.20 53.35 3.04 0.69 SEM 0.01 0.58 0.24 0.29 0.44 0.13 SEM: Stndrd error of mens, Mens long the sme column designted y different superscripts differ significntly (p<0.05) Tle 6: Effect of Genotype x seson interction on egg production performnce of lyers Performnce Prmeters -------------------------------------------------------------------------------------------------------------------------------------------------- Averge Hen-housed Averge Averge weekly egg Egg weekly weekly Body production Feed intke weight egg mortlity Genotype Seson weight (kg) (%) (g/ird/dy) (g) crcks (%) (%) Bovns Hot-dry 1.65 65.76 91.46 51.34 5.40 1.67 Brown Wet 1.73 71.68 99.45 53.53 1.99 0.73 Lohmnn Hot-dry 1.71 70.85 90.34 53.09 4.84 0.78 Brown Wet 1.79 78.16 97.57 54.31 2.00 0.37 SEM 0.01 0.58 0.24 0.29 0.44 0.13 SEM: Stndrd error of mens, Mens long the sme column designted y different superscripts differ significntly (p<0.05) Effect of seson: The men ody weight, hen-housed het urden. Alterntively, hrsh temperture my result egg production, feed intke, egg weight, egg crcks nd in gret reduction in the function of the oviduct (Arim mortlity in the hot-dry nd wet sesons re shown in et l., 1976). The hevier eggs lid y irds in the wet Tle 4. Seson significntly (p<0.05) ffected ll the seson might e due to the liner reltionships mong prmeters studied. Body weight, hen-housed egg egg weight, feed intke nd ody weight. The influence production, feed intke nd egg weight were higher in of ody weight on egg size hs een reported (Leeson the wet seson compred with the hot-dry seson. o nd Summers, 1997). A temperture higher thn 26 C Incidence of egg crcks nd mortlity ws significntly especilly during the hot seson of the yer usully higher in the hot-dry seson. High temperture nd depresses egg qulity (Oluyemi nd Roerts, 2000). humidity influence the rte nd extent of growth in The present findings on egg crcks corroorte this s irds. The etter performnce in ody weight in the wet its incidence ws higher in the hot-dry seson where seson could e s result of high feed consumption tempertures could get to the extremes. The deleterious nd utiliztion which re chrcteristic of cooler effect of therml stress could e responsile for the high environmentl conditions. Al-Rwi nd Aou-Ashour mortlity rte recorded in the hot-dry seson. This (1983) reported tht ccelerted ody weights conforms with the oservtion of Bnnor nd Ogunsn ssocited with cooler temperture were relted to (1987), ut contrdicts the findings of Mmereole nd excessive feed consumption. In similr study-crried Omeje (2005) tht mortlity rtes of the wet seson were out y Njoy nd Picrd (1994), het stress, s oserved higher thn tht of the dry seson. in the hot-dry seson hd negtive effect on growth nd feed intke of lying hens. The decrese in feed consumption, one of the ppetite control fctors, is considered s function of the regultion of cloric intke. Additionlly, hevier ody weight would require more feed for mintennce purposes. Birds lid more eggs in the wet seson. The lower lying rte mong irds during the hot-dry seson my e due to the inility to stisfy their thermo requirement (Lin et l., 2006). In hot environment, chickens grow nd ly y exerting n effort to mintin their ody temperture within norml rnge to cope with stress response nd to ensure their viscerl orgns function under hevier Effect of genotype housing system interction: The interction etween genotype nd housing system is shown in Tle 5. This interction significntly (p<0.05) ffected hen-housed egg production, feed intke nd mortlity. Body weight, egg weight nd egg crcks were not significntly (p>0.05) influenced. Bovns Brown in cges lid more eggs thn those on deep litter. Similrly, Lohmnn Brown in cges lid significntly more eggs thn their deep litter counterprts. This is n indiction tht there is no chnge in rnking of the irds under the two housing systems. With regrd to feed intke, Bovns Brown performnce ws equl in oth 437
Tle 7: Effect of Housing system x seson interction on egg production performnce of lyers Performnce Prmeters ------------------------------------------------------------------------------------------------------------------------------------------------ Averge Hen-housed Egg Averge Averge Housing weekly ody egg production Feed intke weight weekly egg weekly System Seson weight (kg) (%) (g/ird/dy) (g) crcks (%) mortlity (%) Bttery Hot-dry 1.67 71.42 90.51 52.71 5.52 0.86 Cge Wet 1.77 76.71 97.07 54.10 1.84 0.50 Deep litter Hot-dry 1.68 65.19 91.29 51.73 4.71 1.59 Wet 1.76 73.14 99.95 53.73 2.14 0.61 SEM 0.01 0.58 0.24 0.29 0.44 0.13 SEM: Stndrd error of mens, Mens long the sme column designted y different superscripts differ significntly (p<0.05) housing systems, while the reverse ws the cse in significntly ffected ll the ody prmeters, with irds Lohmnn Brown, s irds on deep litter consumed giving etter results in the wet seson compred with more thn those in cges. Mortlity ws higher on deep the hot-dry seson. litter for Bovns Brown while Lohmnn Brown Genotype housing system, genotype seson nd showed no difference in performnce under oth housing system seson interctions produced systems. Although ody weight nd egg weight were significnt results. These reveled the equl nd higher in the ttery cges for oth genotypes, these seprte rnkings of the experimentl irds under the were however, not sttisticlly significnt. Egg crcks two housing systems nd sesons. were higher in the deep litter for Bovns Brown while in Considering the deleterious effects of het stress s the Lohmnn Brown it ws higher in the cge, showing chnge in the rnking of the irds. The present result on egg weight disgreed with tht of Akinokun nd Benyi (1985), where significnt genotype x environment oserved in this investigtion, poultry houses should e constructed with mterils such s sestos roofing sheets tht reduce the effect of het; while there should e room for proper ertion. Controlled feeding regime interction ws found. ttenutes the effect of therml stress. Wet feeding done Genotype seson interction hd significnt (p<0.05) proly once in dy would increse the dry mtter effects on ll the performnce prmeters studied intke. The dietry inclusion of some mino cids such (Tle 6). Body weight, hen-housed egg production, feed s lysine nd rginine will improve feed efficiency. intke nd egg weight were higher in the wet thn the Vitmins nd minerls should lso e dequtely fed to hot-dry seson for oth genotypes. Egg crcks nd enhnce production. Improved mngement prctices mortlity were more in the hot-dry seson compred such tht pullets would strt lying t the eginning of with the wet seson. The finding on mortlity is the riny (wet) seson re eqully dvocted. More inconsistent with wht ws reported y Mmereole nd Omeje (2005), where genotype x seson interction hd elorte investigtion involving other exotic strins no significnt effect on this trit. The gret performnce should lso e crried out. recorded in the wet seson is ssocited with cooler temperture. Acknowledgment Shown in Tle 7 is the effect of housing The uthors re highly indeted to Hon. Muhmmed system seson interction on egg production Umr, the Mnging Director of Shu Poultry Frm, performnce of irds with the exception of mortlity in the ttery cge system. Body weight, hen-housed egg production, feed intke nd egg weight were significntly Lfi, Nsrw Stte nd the Frm Mnger, Mllm Muhmmed Chnso Irhim for their ssistnce nd support during the study period. (p<0.05) higher in the wet thn hot-dry seson for oth housing systems. Egg crck incidence ws higher in the hot-dry seson for oth husndry systems, likewise mortlity on deep litter. Birds in cges were not different in mortlity rte under oth sesons. The impliction of this is tht the survivility of irds in cges is higher compred with those on deep litter. Conclusion: The results of this study showed tht Lohmnn Brown ws superior to Bovns Brown in ody weight, hen-housed egg production, egg weight nd mortlity rte. Birds in cges performed etter thn those kept on deep litter in terms of hen-housed egg production, egg weight nd mortlity. Seson References Adeyemi, O.A., R.A. Awosny nd O.E. Fsin, 2002. A survey of On-Frm egg crcks in Ogun Stte, Nigeri. The Ogun J. Agri. Sci., 11: 166-176. Akinokun, O. nd K. Benyi, 1985. The effect of genotype nd housing on the lying performnce of chickens in south western Nigeri. Bull. Anim. Helth Product. In Afric, 33: 147-151. Al-Rwi, B.A. nd A.M. Aou-Ashour, 1983. Performnce of lying hens under different housing nd environmentl conditions. World Rev. Anim. Product., 19: 54-60. 438
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