Interntionl Journl of Poultry Science 4 (): 64-70, 005 ISSN 168-8356 Asin Network for Scientific Informtion, 005 Evlution of the Growth Potentil of Locl Chickens in Mlwi T.N. Gondwe* nd C.B.A. Wollny Institute of Animl Breeding nd Genetics, Animl Breeding nd Production in the Tropics, Georg-August Universität Göttingen, Kellnerweg 6, 37077, Göttingen, Germny E-mil: tgondwe@gwdg.de Astrct: The growth potentil of locl chickens in Mlwi ws evluted y compring their growth performnce under cge-fed nd free-rnge mngement conditions. Chicks (n = 106) were collected from 39 frmers in 19 villges nd individully rised in cges from n verge ge of 9 weeks to 0 weeks. Onfrm mde growers msh (17% CP) ws fed nd irds were treted ginst common diseses nd prsites. Htch mtes (n = 141) of cge-rised chicks remined on frmer household flocks nd were rised y their dm hens under scvenging conditions. These irds were rised in two tches etween Octoer nd Decemer 00, nd etween Jnury nd Mrch 003, which were corresponding with hot-dry nd wrm-wet sesons, respectively. Sex of chickens, villge, mngement nd mngement x tch interction significntly (p<0.05) influenced growth trits. The vlues for irds under cge-mnged conditions were significntly (p<0.05) 7, 39, 4, 5 nd 41% higher thn for irds under scvenging conditions, for weight t 0 weeks, overll dily weight gins, specific growth rte nd growth efficiency, respectively. Phenotypic vrince for dily weight gins nd specific growth rtes were 17 nd 1%, respectively lower for cge-fed thn for free rnge irds. Correltion coefficients of growth trits mesured etween cge-fed nd scvenging conditions were low (r = 0.1-0.53, p<0.05), indicting possile genotype y environment interction. Gross mrgin over feed costs ws MK6.00 per ird (SD, MK7.00). This ws 35% rte of return on feed costs (SD = 38%) or 4% rte of return on initil ird vlue plus feed cost (SD = 6). It is concluded tht growth potentil of locl chickens is only prtilly exploited under scvenging conditions primrily due to feed constrints. Key words: Growth potentil, cge fed, scvenging, locl chickens Introduction The recognized importnce of locl chickens in providing met, csh income, socio-culturl vlues to rurl people nd their efficient scvenging system hs led to incresed reserch on the species during the pst 10 yers. However, most of these studies hve een seline surveys nd interviews (Pedersen, 00). These studies hve generted informtion on locl chicken production, their functions to rurl households nd demonstrted tht the system is complex with mny constrints such s low productivity of met nd eggs, nd high mortlity (Guèye, 1998). Becuse of little or no investment into the system, production of locl chickens is low cost, mkes use of y-product resources nd is thus efficient (Aini, 1990). Growth is compound trit influenced y genetic nd mngement, especilly nutrition nd helth. The villge scvenging condition is vrile, without stndrd husndry system (Kitlyi, 1998). Performnce of locl chickens is thus lso vrile under trditionl production system. While it is importnt to know how determine production potentil, especilly when compred to the scvenging villge conditions. The ojectives of this study were to determine growth potentil of locl chickens under cge-mnged system; nd to compre their growth with locl chickens under free-rnging system in the villges. The hypothesis to e tested ws tht the villge free-rnging system limit expression of growth potentil of locl chickens. Mterils nd Methods Experimentl site: This study ws conducted t Bund College of Agriculture (BCA) locted 30 km west of Lilongwe. Fifty (50) metolic cges of 34 x 33 x 33 cm size were constructed loclly from welding wire nd plced inside uilding, which hd open sides covered with wire mesh for ventiltion. Ech cge ws fitted with wter nd feed troughs loclly mde from urnt cly nd curved on top to minimize feed spillge. The tril on scvenging conditions ws conducted in the surrounding villges on households of frmers who prticipted in the villge poultry project. These villges chickens perform under scvenging conditions, surround BCA, nd re locted within the coordintes o o knowledge of their production potentil is lso essentil 14.10 S, 33.47 E nd ltitude is pproximtely 100 m (Pedersen, 00). This knowledge cn guide sound ove see level (Grmin GPSMAP 76CS, Grmin Ltd, formultion of strtegies to improve locl chickens. www.grmin.com). Over the pst four yers, nnul Trils under controlled environments cn help to precipittion for Lilongwe verged 93 mm (Ntionl 64
Gondwe nd Wollny: Growth potentil of locl chickens These were on free-rnge (scvenging) with their dm- hens. Their growth ws monitored during the sme period s their contemporry counterprts in cges. Weighing of ll irds ws on the sme dy on weekly intervls. Mngement followed wht frmers prcticed including the prticiptory communl Newcstle disese vccintion. Sttisticl Office, 003). Two sesons re distinct; wet wrm seson (Novemer to April) nd dry seson (My to Octoer). Most of the smllholder frmers elong to the Chew trie nd prctice susistence griculture in crop-livestock integrted system. Aout 8% of these frmers own locl chickens using free-rnge, scvenging low input-low output production system (Gondwe nd Wollny, 00). Different phenotypes nd different ge-groups scvenge together. Frmers errticlly provide supplement feed to their chickens, minly using mize rn (10.4% CP). Through community prticiption, frmers were vccinting their chickens ginst Newcstle disese (NCD) using L sot live vccine (1000 doses cloned, Lohmnn Animl Helth GmH) t three monthly intervls, etween My nd Decemer. Frmers shred the cost of the vccine. Experimentl chickens in cges: Fifty growing chicks collected from frmers in the study re were individully llocted into the cges t rndom. From ech frmer, up to three chicks from the sme hen were rndomly chosen. The htch dtes of these chicks nd their mother hens were recorded. Chicks were of n verge ge of eight (8.5) weeks when introduced to cges. Chicks were tgged, sexed nd phenotypiclly chrcterized. Initil weight ws tken for ech ird. In totl, 39 frmers from 19 villges in the study re contriuted to the study. The periods for the pre-tril nd tches 1 nd were, respectively, August - Septemer 00; Octoer - Decemer 00; Jnury - Mrch 003. Ech tch covered on verge 1 weeks. Feeding in cges: During the study period, chicks were offered on-frm formulted growers msh (Tle 1). Growers msh ws chosen since it is fed to commercil lyer chicks during growing phse. Feed nd wter were offered d li in the cges. Helth mngement of chicks in cges: Birds in cges were treted ginst helminths (Piperzine from CAPS, Zimwe), coccidiosis (Amprolium from Netherlnds) nd other prophylxis (Triple Sulf from Antec Helth cre Afric Ltd, South Afric). Those tht hd externl prsites were dusted nd smered with tick greeze (Cooper Ltd, Zimwe). Other tretments were dministered upon noticing prolem on individul irds. Helth ws monitored on dily sis. Tretment ws, however, dministered to ll irds to prevent possile infection to other irds. If irds died during the study, it ws rrnged to return to frmers replcement ird of similr ge tken from the College stock. Experimentl chickens under free-rnge: The clutch mtes of chicks (offspring from sme htch) rought to cges remined t the frmers home in the villges. Dt collected: Birds were in the cges until they reched 0 weeks of ge. Altogether there were three tches of chicks introduced in the cges. However, the first tch ws on pre-tril sis nd ws not e included in the nlysis. With two tches, 100 chicks were oserved. Of these, 70% were femle nd 30% 1 mles. Distriution in terms of colour were 4.76% Chiphuluts, 0.95% Kwngi, 1.38% Mwng, 6.67% Ykud, 15.4% Yofir nd 0.00% Yoyer. On weekly sis, live weights of chicks were tken using digitl scle (Ohus CS5000, Ohus Corp, Pine Brook, NJ, USA; mximum of 5 kg, grduted to g). Dt on free-rnge irds (n = 147) were comined with dt from cge irds nd sujected to similr clcultions descried for cge-mnged chickens pertining to growth trits. Altogether, there were 47 irds included, 40% in cges nd 60% under villge mngement. Femle irds constituted 71%. Distriution y tch is shown in Tle. Dt clcultion nd nlyses: Growth performnce ws determined using live weights nd growth rte prmeters weight gins, specific growth rtes nd growth efficiency. These were clculted s follows Where, WG is weight gin (dily, weekly or overll) per time period in g; LWti is live weight t prticulr week = t; i LWto is live weight for the previous period = to Where, SGR is the specific growth rte in percent growth per dy t prticulr time; ln(lw ti) is nturl log of live weight t week = t; i ln(lw to) is nturl log of live weight t previous week = t ; (t-t ) is the period of weighing o i o converted to dys Where, GE is growth efficiency per time period = t; i WGti is weight gin t time = t; i LWto is live weight t time = to All mesured nd clculted prmeters were tested for normlity using proc univrite, norml nd plot procedure of SAS (SAS, 1999). Normlity ws considered t over 90 % using Shpiro - Wilk (W) test for (1) () (3) 65
Gondwe nd Wollny: Growth potentil of locl chickens Tle 1: Ingredients nd nutritive contents of growers (xn), tken s covrite; hm is the rndom effect of hen; msh rtion fed to chicks (on s fed sis) > ijklmn is the residul error ssumed NID (0, F >). Ingredient Amount (kg/100kg) Btches of production were confounded with seson. Mize 67.61 Btch one ws during hot-dry seson nd tch two in Soyens, full ft, rosted 6.1 hot-wet seson. Btch / sesonl effects will e used Fish mel 3.67 interchngely. Vitmin nd Minerl premix 0.30 Proc mixed REML procedure of SAS (SAS, 1999) ws Iodised slt 0.30 used during the nlysis of vrince for the vrious DL-Methionine 0.01 prmeters. Lest squre mens were seprted into Lime.00 significnt differences y the lest significnt difference Totl 100.00 procedure (LSD). Nutrient contents 1 Dry mtter, % (nlyzed) 95.34 An estimte of genotype x environment (G X E) interction ws done y correlting performnce of locl Crude Protein % (nlyzed) 17.95 Clcium % (clculted) 1.00 ME, kcl per kg (clculted) 333 Phosphorus % (clculted) 0.83 Crude Fire, % (clculted).43 Lysine % (clculted) 0.93 Methionine % (clculted) 0.3 1 Anlsyzed mens nutrients were nlyzed in the l; clculted mens nutrients were clculted sed on nutrient vlues of ingredients. Tle : Distriution of chicks llocted into cges nd on-frm with numer of their hens Btch Numer Numer of chicks of hens ------------------------------------ Cge On-frm 1 50 79 4 50 68 100 147 normlity (n < 000). All prmeters were normlly os distriuted nd dt nlyses proceeded without trnsformtions. chickens etween two mngement systems sed on dm-hen REML BLUP vlues otined using proc mixed procedure of SAS (SAS, 1999). Economic evlution of feed costs: Feed costs (FC) during cges were clculted y multiplying totl feed intke (TFI) y price per kg feed. Revenue (RV) ws clculted y multiplying weight t 0 weeks per ird y frm-gte price of MK14.79 per kg live weight of chicken (price determined from prticipting frmers selling prices for chickens). Initil vlue of chicken ws clculted y multiplying initil weight per ird y frmgte price per kg live weight. Gross mrgin over feed cost (GMOFC) ws clculted y sutrcting FC from RV. Return on FC ws clculted s GMOFC s percentge of FC, while return on ird nd FC ws clculted s GMOFC s percentge of initil ird vlue plus FC. These prmeters were normlly distriuted nd were nlyzed for their mens nd stndrd devitions. Anlysis of vrince ws performed to test effect of tch nd sex using generl liner model procedure of SAS (SAS, 1999). Model of nlyses: The model of nlysis included the mngement effect to compre growth vrition mong irds etween cge-mnged nd free-rnge mnged systems. Effects of colour, two-wy (except tch x mngement) nd three-wy possile interctions were not significnt (p>0.05) nd were hence dropped from the model. Initil weight ws more importnt s covrite thn initil ge nd htch weights. All nlyses were sed on overll production in this cse. The finl model fit to dt ws y ijklmn = µ + i + m j + s k + v l + h m + $(x ijklmn - xn) + > ijklmn (4) Where, y is the oserved mesure for ird n; µ is the ijklmn overll men to ll irds; is the fixed effect of tch of i production (I = 1,); m is the fixed effect of mngement j (j = cge, scvenging); s is the fixed effect of sex of ird k (k = 1,); v is the fixed effect of villge (l= 1,, 19); $ is l the liner regression coefficient of the mesure on initil weight of ird; (x - xn) is the oserved initil weight of ijklmn the n-th ird djusted from the overll men initil weight Results Fixed effects of growth performnce: Tle 3 shows fixed fctors nd their effects on overll vlues for growth trits. Btch of production significntly (p<0.05) influenced SGR while sex of irds, villge, mngement nd mngement x tch interction significntly (p<0.05) influenced more growth performnce trits. Initil live weight ws not significnt (p>0.05) for overll nd dily weight gin. Growth performnce etween cge-fed nd scvenging chicken mtes: Birds under cge-fed condition were superior to clutch mtes under freernge villge conditions (Tle 4). Bsed on overll vlues, irds under cge-fed mngement were significntly (p<0.05) 7.04, 39.01, 41.54, 5.5 nd 41.18% superior thn irds on free-rnge for live weights, overll weight gins, dily weight gins, SGR nd GE, respectively. 66
Gondwe nd Wollny: Growth potentil of locl chickens Tle 3: Effects of fixed fctors on overll growth chrcteristics of locl chickens under cge nd free-rnge mngement Effect Weight t 0 weeks Overll weight gin Dily weight gin SGR GEF Btch of production ns ns ns *** ns Sex of irds *** *** ** ns * Villge * * *** ns ns Mngement *** *** *** *** *** Btch x mngement * * * * ns Initil weight *** ns ns *** *** SGR = specific growth rte (% growth per dy); GE = growth efficiency (g finl weight gin / g initil weight); Significnt levels (F Test), * = p<0.05; ** = p<0.01; *** = p<0.001; ns = not significnt (p>0.05) Tle 4: Overll productivity of locl chickens under cge-fed nd free rnge villge conditions (lsmens nd stndrd errors) Trit Btch Mngement ------------------------------------------------------------------------------------- Cge-fed Free- rnge (villges) ----------------------------------- ------------------------------------ Men SE Men SE Live weight (g) t 0 weeks 1 1131.85 47.36 835.3 49.37 10.04 40.33 860.17 46.98 Overll 1076.94 3.1 847.70 34.55 Weight gin (g/period) 1 871.75 47.36 575.13 49.37 761.94 40.33 600.07 46.98 Overll 816.84 3.1 587.60 34.55 Dily weight gin (g/dy) 1 10.68 0.63 6.61 0.66 10.58 0.53 8.41 0.63 Overll 10.63 0.4 7.51 0.46 SGR (% / dy) 1 1.665 0.119 1.167 0.13.045 0.105 1.796 0.116 Overll 1.855 0.087 1.481 0.091 GE (g/initil weight) 1 3.471 0.01.417 0.09 3.97 0.169.377 0.0 Overll 3.384 0.133.397 0.146 SGR = specific growth rte (% growth per dy); GE = growth efficiency (g finl weight gin / g initil weight) Vrince components nd G X E interction: Effect of evlution of feed costs (Tle 7) showed positive mngement ws compred on ehviour of vrince men gross mrgin with wide vrition. Similrly, oth components s shown in Tle 5. Mngement did not rte of return on feed costs nd on feed nd ird costs ffect phenotypic vrince for finl weight nd weight showed wide vrition. Btch nd sex effects were not gins. Phenotypic vrince for dily weight gins nd significnt (p>0.05, Tle 8) SGR were 16.9 nd 1.3%, respectively, lower for cgefed thn for free-rnge irds. On the other hnd, Discussion phenotypic vrince for GE ws 7.8% higher in cge-fed Growth potentil: Demeke (003) oserved higher live thn in free-rnge irds. The etween dm-hen vrince weights (1300g, intensive; 985 g, free-rnge) in ws lrger in free-rnge irds thn in cge-fed irds. Ethiopin locl chickens t 0 weeks of ge thn the The etween dm-hen vrince ws lso lrger thn the results from this study. The difference could in prt e within ird vrince compring within free-rnge irds. due to different initil live weights, which were not Correltion coefficients etween cge-fed nd freernge locl chickens (Tle 6) were significntly strted from 9 weeks while in Demeke s study, feeding djusted for in Demeke s study. In this study, feeding (p<0.05) different from zero ut lower thn 50% for ll strted from one dy old. However, dily weight gins trits except for dily weight gins. SGR hd lowest re comprle. On the other hnd, the trend for live coefficient. weights nd dily weight gins gree with those in this study, wherey their irds under intensive system were Economic evlution of feed costs in cges: Economic 4% hevier thn irds under scvenging conditions. 67
Gondwe nd Wollny: Growth potentil of locl chickens Tle 5: Vrince components y mngement of locl chickens for growth trits Component Weight t Weight gin Dily weight SGR GE 0 weeks gin ------------------------ ---------------------- -------------------------- --------------------- --------------------------- ó SE ó SE ó SE ó SE ó SE Between dm hen Cge 1109 7114 1109 7114 0.8388 0.846 0.0366 0.0 0.764 0.150 (ó ) Free-rnge 5107 9404 5107 9404 4.914 1.891 0.0835 0.050 0.530 0.03 Within irds Cge 4416 446 4416 446 4.970 0.841 0.0956 0.017 0.5844 0.10 (ó residul ) Free - rnge 1183 06 1183 06.7045 0.5 0.0845 0.017 0.666 0.050 Totl (ó p ) Cge 3655 3655 5.8109 0.13 0.8608 Free - rnge 36939 36939 6.9959 0.1680 0.7986 SGR = specific growth rte (% growth per dy); GE = growth efficiency (g finl weight gin / g initil weight) Tle 6: Correltion coefficients etween BLUP vlues of dm hens for cge fed nd free - rnge mnged locl chickens Trit Weight t 0 weeks Weight gin Dily weight gin SGR GE Coefficient 0.384 0.384 0.59 0.19 0.376 Significnce level ** ** *** * * SGR = specific growth rte (% growth per dy); GE = growth efficiency (g finl weight gin / g initil weight); Significnt levels, * = p<0.05; ** = p<0.01; ***=p<0.001 The sttus nd limittion of scvenging feed resource vrince for free-rnge thn for cge-mnged irds is se is the min re of reserch in mny countries in expected since free-rnge irds continued with their Afric (Roerts, 1999; Olukosi nd Soniy, 003). In dm-hens, nd hence hd more common influence their prediction, Olukosi nd Soniy (003) estimted from their dm-hens. Nture of dt in this comprison dily feed intke of 0 g per ird per dy under did not llow for determining the etween ird vrince. scvenging condition, which ws lower thn feed intke Hence, the dm-hen vrince includes ll genetic, oserved in the study (45-59 g per dy) under cge mternl nd common environment effects. Since mngement. The findings support views tht villge effect ws tken cre of, the common scvenging feed resource se is often indequte environment in this cse ws flock of the irds. Birds quntittively nd qulittively (Huque, 1999; Ndegw et under cge mngement were seprted from their l., 001; Dn nd Ogle, 00), depending on flock dm-hens, nd hence the low etween dm-hen size, environment nd seson (Gunrtne, 1999; vrince tht ws in this cse, crry over effect. Roerts, 1999). Kitlyi (1998) reported tht Hu et l. (1999) reported tht mternl effects re scvenging feed is constrint to locl chicken growth nd reproductive potentil, nd emphsized on the need to provide supplement feeds to irds. The mjor input to irds under cge mngement ws feeding of lnced rtion, grower s msh. Disese intervention my hve moderte in poultry, only contriuting less thn 10% of totl vrince nd depend on trits. Flconer (1989) resons tht mternl ffects re more importnt in mmmls. Pinchsov (1991) reported tht mternl effects in chickens dispper within the first three weeks differed in intensity (etween cge-fed nd villge of chicks life. Prdo - Gonzlez et l. (003) oserved chickens) ut ws lso tking plce in the villges. The significnt effect of mternl effect for weights t htch difference in growth performnce oserved in the study nd fourth week of Creole chickens in Mexico nd not ws therefore due to feeding mngement. The therefter. The vrinces in this study show potentil significnt superiority of irds under cge mnged mternl effects tht re high nd persist for long time conditions over villge free-rnge irds shows tht feed in chickens. Mternl effects from literture rose from constrint limits expression of growth potentil in locl the dm-hen influence on the egg (size, weight, shell chickens. qulity nd yolk composition) tht is descried s the The significnt effect of villge on finl weight, nd only vehicle for mternl effects in poultry (Sewlent nd weight gins is proly due to differences in flock Johnsson, 000). This is true when irds re rised structure, mngement, scvenging iomss nd under intensive system nd re seprted from their nutritionl pressure under free-rnge, nd disese chllenges tht vry from villge to villge. Villge effect dm-hens t htch. In free-rnging chickens, dm-hen ws more pronounced in irds under free-rnge thn tkes cre of chicks till wening, hence post htch those fed in cges. This is ovious since irds in cges mternl effects re expected. The oserved vrince were exposed to villge conditions only efore they were nd the difference show possile post htch mternl rought to cges. influence on the irds under free-rnge system. The mgnitude of such mternl effect is however, trit nd Vrince components: The lrger etween dm-hen mngement specific. 68
Gondwe nd Wollny: Growth potentil of locl chickens Tle 7: Descriptive sttistics for economic prmeters of feed costs for chickens under cge mngement Prmeter n Men SD Minimum Mximum Totl feed intke, g 100 3473.5 884.7 1048.0 5536.0 Feed cost per ird, MK 100 83.36 1.3 5.15 13.86 Income per ird, MK 97 109.44 33.47 6.13 194.19 GMOFC per ird. MK 96 5.69 6.6 (48.4) 90.08 Return on feed cost, % 96 34.80 38.10 (4.33) 150.63 Return on ird & feed cost, % 96 4.13 5.90 (9.9) 106.15 n = numer of irds; SD = stndrd devition; GMOFC = Gross mrgin over feed cost; MK = Mlwi Kwch (1US$ = MK85.00); Vlues in rckets re negtive. Tle 8: Lest squre mens nd SE for gross mrgin over feed cost nd rtes of returns y tch nd sex of irds Fctor GMOFC, MK Return on feed cost, % Return on ird nd feed cost, % Lsmen SE Lsmen SE Lsmen SE Btch 1 30.68 4.09 43.15 5.85 9.73 3.98 4.63 3.98 30.76 5.70 1.59 3.88 Sex Femle.67 3.4 31.79 4.63 1.97 3.15 Mle 3.65 5.01 4.11 7.17 9.35 4.88 GMOFC = Gross mrgin over feed cost; MK = Mlwi Kwch (1US$ = 85.00 MK) G x E interction: In generl, genetic prmeters could e etter estimted under these conditions of improved feeding. However, there is need to check if locl chickens express some genotype y environment (G x E) interction, if the results determined under improved feeding could e pplicle to locl free-rnging environment. In genetic nlysis, genetic correltions etween 0.9 nd 1.0 suggest tht two trits re the sme (Kerr et l., 001). Lower correltion coefficients imply smll covrince etween the two oservtions. This indictes presence of stronger interction (Lin nd Togshi, 00). The dm-hen effect nd rnking ws expected to e similr in the two mngement systems nd hence show high correltion coefficients. The results otined showed correltion coefficients rnging from 0. - 0.53. Common covrince in these correltions ws due to genetic nd mternl effects. The low correltion coefficients show possiility of individul G x E interction eing expressed in growth trits for locl chickens. This mens locl chickens re sensitive to environmentl chnges. Use of prmeters determined under improved feeding in this cse is only to show potentil performnce of locl chickens under freernging environment (Prdo - Gonzlez et l., 003). Economic evlution of feeding locl chickens: Gross mrgins nd rtes of returns on feed costs were positive. The oserved rtes of return re possile contriution of high costs of feed nd poor feed conversion efficiency of these locl chickens. This return declined when initil vlue of irds ws included. When ll costs, such s lour involved with intensifiction nd tretment re tken into considertion, it would not e economiclly justifile to improve feeding of locl chickens, s oserved y Demeke (003). Pedersen (00) found negtive gross mrgins of US$8 for intensively mnged locl chickens from dy old in Zimwe. Locl chickens re pproprite for the low input scvenging system. Lwesy et l. (004) reported positive response of supplementing locl chickens loclly formulted rtion on erly chick growth rte nd return to ly of hens. However, the rtion ws not economiclly vile. This poses chllenge to utilize the dvntges of the low-input system while t the sme time ttempt to chieve their genetic potentil. On ssumption tht the low-input system will previl in rurl communities nd tht currently there is no suitle reed to sustitute locl chickens, investigtions into optiml feeding strtegies rnging from supplement feeding to whole feeding re encourged within the frmework of the frming system. Conclusion: The growth potentil of locl chickens is not fully exploited under free-rnge (scvenging) conditions due to indequte feeds. Feeding mngement contriutes to out 30% of their growth potentil. Growth of locl chickens cn e enhnced through improved mngement under free-rnging conditions. The option of improved feeding of locl chickens under confined conditions is, however, economiclly not ttrctive enough to wrrnt frmers dopting it. References Aini, I., 1990. Indigenous chicken production in South Est Asi. World s Poult. Sci. J., 46: 51-57. Dn, N. nd B. Ogle, 00. Effects of scvenging on diet selection nd performnce of Rhode Islnd Red nd Fyoumi reeds of chicken offered choice of energy or protein feeds. Trop. Anim. Helth Prod., 34: 417-49. 69
Gondwe nd Wollny: Growth potentil of locl chickens Demeke, S., 003. Growth performnce nd survivl of Lin, C.Y. nd K. Togshi, 00. Genetic improvement in locl nd White Leghorn chickens under the presence of genotype y environment scvenging nd intensive systems of mngement interction. Anim. Sci. J., 73: 3-11. in Ethiopi. Reserch for Rurl Development, 15, Lwesy, H., R.K.D. Phoy, A.C.L. Sfloh nd T.N.P. 11: 003. http://www.cipv.org.co/lrrd/lrrd 15/11/ Gondwe, 004. Rering chicks in enclosure under deme1511.htm villge conditions: Effect on chick growth nd Flconer, D.S., 1989. Introduction to quntittive reproductive performnce of mother hens. Livestock genetics. ELBS Third Edition. Longmn Scientific Reserch for Rurl Development. Vol. 16, Art. #89. nd Technicl, Englnd. Retrieved Decemer 7, 004, from Gondwe, T.N.P., A.J.D. Amli, F.C. Chiler, H. Lwesy, http://www.cipv.org.co/lrrd/lrrd16/11/ wesr16089. nd C. Wollny, 1999. Rurl poultry iodiversity in htm Lilongwe nd Mzuzu Agriculturl Development Ntionl Sttisticl Office, 003. Mlwi in Figures 003. Divisions (ADD), Mlwi. Mlwi J. Sci. Tec., 5: 17- www.nso.mlwi.net. 5. Ndegw, J.M., R. Med, P. Norrish, C.W. Kimni nd A.M. Gondwe, T.N.P. nd C.B.A. Wollny, 00. Trditionl Wchir, 001. The growth performnce of reeding systems in smllholder rurl poultry in indigenous Kenyn chickens fed diets contining Mlwi. In: Session 5, Developing Sustinle different levels of protein during rering. Trop. Anim. Breeding Strtegies in Medium to Low input Helth Prod., 33: 441-448. th Systems. 7 World Congress on Genetics Applied Olukosi, O.A. nd E.B. Soniy, 003. Determintion of to Livestock Production, August 19-3. Montpellier, the quntity of scvengele feed for fmily poultry Frnce. on free rnge. Livestock Reserch for Rurl Guèye, H.F., 1998. Villge egg nd fowl met production Development, 15, 5:003. http://www.cipv.org.co/ in Afric. World s Poult. Sci. J., 54: 73-86. lrrd/lrrd15 /5/0luk 155.htm Gunrtne, S.P., 1999. Feeding nd nutrition of Pedersen, C.V., 00. Production of semi-scvenging scvenging villge chickens. First INFPD / FAO chickens in Zimwe. PhD Thesis. Royl Electronic Conference of Fmily Poultry. Veterinry nd Agriculturl University, Copenhgen, http://www.fo.org/g/g/gp/lp/fmpo1/fmpo. Denmrk. htm Pinchsov, Y., 1991. Reltionship etween weight of Hu, Y.H., J.P. Poivey, R. Rouvier, C.T. Wng nd C. Ti, htching eggs nd susequent erly performnce 1999. Heritilities nd genetic correltions of ody of roiler chicks. Br. Poult. Sci., 3: 109-115. weights nd fether length in growing muscovy Prdo - Gonzlez, E.A., L. Rmirez - Avil, nd J.C. selected in Tiwn. Br. Poult. Sci., 40: 605-61. Segur - Corre, 003. Genetic prmeters for ody Huque, Q.M.E., 1999. Nutritionl sttus of fmily poultry weights of Creole chickens from Southern Mexico in Bngldesh. First INFPD / FAO Electronic using n niml model. Livest. Res. Rurl Dev., 15, Conference of Fmily Poultry. http://www.fo. org/g/ 1:003. http://www.cipv.org.co/lrrd/lrrd 15/1/ prd g/gp/lp/fmpo1 /fmpo. htm 151.htm Kerr, C.L., R.H. Hmmerstedt nd G.F. Brto, 001. Roerts, J.A., 1999. Utiliztion of poultry feed resources Effects of selection for exponentil growth rte t y smllholders in the villges of developing different ges on reproduction in chickens. Avin countries. In. Poultry s tool in poverty erdiction nd Poult. Bio. Rev.,1: 17-136. nd promotion of gender equity. Kitlyi, A.J., 1998. Villge chicken production in rurl http://www.husdyr.kvl.dk/htm/php/tune 99/8- Afric, household food security nd gender issues. Roerts.htm Animl Production nd Helth Pper No. 14. Food SAS., 1999. SAS /STAT Users Guide, Version 8.1, Cry, nd Agriculturl Orgniztion of the United Ntions, NC, USA. Rome. Sewlent, A. nd K. Johnsson, 000. Egg weight nd Kitlyi, A.J., 1999. Fmily poultry mngement systems reproduction trits in lying hens: estimtion of in Afric. First INFPD / FAO Electronic Conference of direct nd mternl genetic effects using Byesin Fmily Poultry. http://www.fo.org/g/g/gp/lp/ pproch vi Gis Smpling. J. Anim. Sci., 70: 9- fmpo1/fmpo.htm 16. 1 Locl nmes reported y Gondwe et l. (1999). 70