OPEN ACCESS World J Life Sci. and Medical Research 2011;11(3): (3):60 al., 2011. Growth traits of harco-black cockerel chicken Ojedapo et al Original Article Effect of Age and Cage Position on the Growth Traits of Harco-black Cockerel Chicken in the Derived Savanna Zone of Nigeria Life Science ISSN 2249-0574 Lamidi Oladejo OJEDAPO 1, *, Tosin Ademola ADEDEJI 2, Shola Rasheed AMAO 2, Saliu Akanni AMEEN 2 ABSTRACT [ENGLISH/ANGLAIS [ENGLISH/ANGLAIS] ANGLAIS] Affiliations: 1 The study was conducted to determine the effect of age and cage position on the growth traits of harco-black cockerel chicken. Two hundred and fifty birds were used for the study and were randomly placed equally in the upper and the lower tier cage for the period of sixteen weeks. The parameters taken were body length (BLT), comb length (CLT), Keel length (KLT), Drumstick (DSK), Shank length (SLT) and Chest girth (CGT). Significant effect (p < 0.05) of cage tier and age on DSK, KLT, SLT, CGT and CLT of Harco-black cockerel were observed. The upper tier cage shows higher significance for most of the growth traits measured. The correlation coefficients at 9th week of age were only highly positively significant (p < 0.001) correlation between CGT and KLT while that of 14th week of age shows a highly negatively significant (p < 0.001) correlated between the BLT and SLT at the upper diagonal. At the upper diagonal of the 19th week of age, CLT against DSK shows a highly positively significance (p < 0.001) correlation, while a high negatively significant (p < 0.05) correlation exist between BLT and KLT.CLT against SLT also shows a highly negatively significance (p < 0.001) correlation. The high positively significant (p < 0.05) correlations exist between BLT and SLT, KLT and SLT respectively at the upper diagonal. At the lower diagonal, a high positively significant (p < 0.05) relationship occurred between SLT and DSK with a highly negatively significant (p < 0.05) correlation between CGT and DSK all the 24 weeks of age. Generally, the correlated coefficients were low to high and positive; it can therefore be concluded that cage tier and age are strong determinant of growth traits in harco-black cockerels. Department of Animal Nutrition and Biotechnology, Ladoke Akintola University of Technology, PMB 4000, Ogbomoso, Oyo State, NIGERIA Keywords: Cockerel, growth trait, cage position, correlation coefficient, derived savanna * Email Address for Correspondence/ Adresse de courriel pour la correspondance: ojedapolam@yahoo.co m RÉSUMÉ [FRANÇAIS/FRENCH] FRANÇAIS/FRENCH] L'étude a été menée afin de déterminer l'effet de l'âge et la position de la cage sur les caractères de croissance de poulet coq Harco-noir. Deux cent cinquante oiseaux ont été utilisés pour l'étude et ont été placés au hasard aussi dans le haut et le bas de la cage de palier pour la période de seize semaines. Les paramètres pris ont été la longueur du corps (BLT), longueur de peigne (CLT), la longueur de quille (KLT), le pilon (DSK), longueur de la tige (SLT) et Tour de poitrine (CGT). effet significatif (P <0,05) de la cage de palier et de l'âge sur DSK, KLT, SLT, la CGT et de la CLT-coq Harco noirs ont été observés. La cage de palier supérieur montre plus grande importance pour la plupart des caractères de croissance mesurée. Les coefficients de corrélation à la 9e semaine de l'âge n'ont été que très positivement significative (P <0,001) corrélation entre la CGT et KLT tandis que celle de la 14e semaine d'âge montre une (p <0,001) très négative importante corrélation entre le BLT et SLT à la diagonale supérieure . À la diagonale supérieure de la 19e semaine de l'âge, CLT contre DSK montre un très positive significative (p <0,001) de corrélation, tandis qu'un haut négative significative (p <0,05) la corrélation existant entre BLT et SLT KLT.CLT contre montre également une très négative significative (p <0,001) de corrélation. La haute positive significative (p <0,05) des corrélations existent entre les BLT et SLT, KLT et SLT respectivement à la diagonale supérieure. Au bas de diagonale, une relation positive forte significative (p <0,05) ont eu lieu entre les modèles SLT et DSK avec un (p <0,05) très négative importante corrélation entre la CGT et DSK toutes les 24 semaines d'âge. En général, les coefficients de corrélation ont été faible à élevé et positif, il peut donc en conclure que la cage de palier et l'âge sont fort déterminant les caractères de croissance chez le coq Harco-noir. Mots-clés: Coq, le trait de croissance, position de la cage, coefficient de corrélation, dérivée de savane 2 Department of Animal Production and Health, Ladoke Akintola University of Technology, PMB 4000, Ogbomoso, Oyo State, NIGERIA Accepted/Accepté: June, 2011 Full Citation: Ojedapo LO, Adedeji TA, Amao SR, Ameen SA. Effect of age and cage position on the growth traits of harco-black cockerel chicken in the derived savanna zone of Nigeria. World Journal of Life Sciences and Medical Research 2011;11(3): (3):60-5. INTRODUCTION income generation, jobs creation, provision of industrial Poultry rearing are now ahead of all other livestock in raw materials and creations of opportunities for scientific terms of economic importance (such as meat production, research) in many countries [1]. The most widely spread OPEN ACCESS © Research | Reviews | Publications, 2011 http://www.rrpjournals.com/ ISSN 2249-0574 World J Life Sci. and Medical Research 2011;1(3)::61 al., 2011. Growth traits of harco-black cockerel chicken Ojedapo et al OPEN ACCESS and most reared is the domestic fowl and they can be derived savanna lies on longitude 40 151 East of classified based on their origin and according to [2], a Greenwich Meridian and latitude 80 151 North of the livestock population survey in 1991 shows that chickens equator while the mean temperature and annual mean has a population of 82.4 million and other livestock put rainfall are 270C and 1247 mm respectively [10]. together are just 31.9 million. This shows that poultry keeping out -numbers all other forms of livestock keeping Experimental Unit in Nigeria. The section of the layer house used has 9 units of cages Geneticist in their concern to improve supply of animal with 2-tier (upper and lower tier) cages. Each unit of the protein developed breeds of animals like the cockerels in cages has seven cells each both at the upper and the lower the avian species and cockerel rearing and management is tier. The section was disinfected with a suitable easier than the broiler production particularly in the rural disinfectant to prevent infection before the introduction of areas where modern facilities including electric supply is the birds. not available. It is also believed that cockerels are less susceptible to diseases as compared to broilers [3]. Experimental Birds and their Management Cages are usually constructed in single, double or triple A total number of two hundred and fifty birds were used stages which are respectively described as 1-tier, 2-tier for the study. Two birds were placed or housed in each and 3-tier. From the past studies, the performance of cell of a unit and this makes up a total number of twenty- chicken have been observed to vary with a number of eight birds per unit on both the upper and the lower tier. factors such as feed utilization and body weight [2], water The birds were managed under intensive system and the availability [4], tier of cages [5], infection [6] and ambient experiment lasted sixteen weeks. They were fed with temperature [7]. standard growers marsh containing 15.85% Crude protein The management system in terms of the cages to which and 2400.8kcal/kg ME for the period of the experiment (16 birds are subjected to affects and determines their quality weeks). The birds were fed and watered under the same [8] and the cage position to which they are kept condition throughout the experiment period determines the quality of their performance [6]. Several factors both genetic and environmental have been Data Collection adduced to be factors that affect their growth. Therefore, it Birds were collected from different units systematically on is essential for researchers to continue to look for ways to a weekly basis i.e. the nine units of the cages were divided enhance the well being of animals while keeping into odd and even numbers and birds were taken from production at high levels. Recent advancement in even number units in particular week and them from odd technology automated number units the following week). For each week, the management system in poultry has had a great influence selected birds were weighed and the measurements of on poultry industries at large, this led to the introduction drumstick length (thigh), body length, keel length, shank of housing system which can be deep litter system, battery length, chest girth, and comb length (all in cm) were cage system or both and other management techniques taken. which includes the use of [9]. Housing of birds have increased productivity and has made poultry more attractive than when they are been Statistical Analysis reared in a free range system. Therefore, the aim of this Data was subjected to the analysis of variance of [11] in a study was to estimate the effect of age and cage position Completely Randomized Design (CRD). Duncan Multiple on the growth traits of Harco black cockerel chicken in Range Test of the same statistical software was used to derived savanna zone of Nigeria. determine the significant differences observed among means. The statistical model for the analysis is as follows MATERIALS AND METHODS Experimental Site Yijk = The experiment was carried out at the Layers House of Yijk = individual measurement of each birds the Teaching and Research Farm, Ladoke Akintola µ = overall mean University of Technology, Ogbomoso. Ogbomoso is a Si = effect of ith age (i= 9, 14, 19 and 24) µ +Si + Aj + (SA)ij + Eijk Where, © Research | Reviews | Publications, 2011 http://www.rrpjournals.com/ OPEN ACCESS World J Life Sci. and Medical Research 2011;11(3): (3):62 al., 2011. Growth traits of harco-black cockerel chicken Ojedapo et al OPEN ACCESS ISSN 2249-0574 Aj = effect of jth cage position (j = 1, 2) while the CGT were significantly (p < 0.05) affected at ages (S*A) ij = Eijk interaction between age i and cage 19 and 24 weeks. However, the KLT, CLT and SLT were position jth significantly (p < 0.05) affected at 14, 19 and 24 week th = random error which is assumed to be respectively. The higher values of DSK, CLT and CGT normally and independently distributed were obtained at the 9, 19 and 24 weeks of age in Harco- with a mean of zero and variance of black cockerel reared at the lower cage tier. Generally, the upper tier had the higher values of growth traits . understudy. RESULTS The means of growth traits of Harco-black cockerels Table 1 shows the means of growth traits of Harco-black reared at different ages within cage tier is as shown in cockerels to different cage tiers within ages. There were Table 2. There were significant (p < 0.05) difference of age significant (p < 0.05) effect of cage tier on the Drumstick on the DSK, KLT, SLT, CGT and the CLT of birds reared (DSK),Keel length (KLT).Shank length (SLT), Chest girth at the upper tier except the BLT. Harco-black cockerels at (CGT) and comb length (CLT) at speculated ages. the lower cage tier had the highest KLT and CLT at 24 Significant (p < 0.05) difference were observed in the DSK weeks of age while the highest values of the DSK and the of the Harco-black cockerels at weeks 9, 14 and 19 of age CLT occurred at the 9th and 19th weeks of age respectively. TABLE 1 Table 1 shows the growth traits (mean ± SEM) of Harco-Black cockerels reared at different cage tiers within ages Age (Weeks) Cage tier n DSK (cm) BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) 9 Upper Lower Upper Lower Upper Lower Upper Lower 20 20 20 20 20 20 20 20 14.65 ± 0.23b 15.63 ± 0.28a 16.11 ± 0.16a 15.30 ± 0.15b 15.53 ± 0.17a 15.03 ± 0.09b 15.86 ± 0.23 15.38 ± 0.13 24.45 ± 0.39 24.20 ± 0.34 24.13 ± 0.22 24.75 ± 0.32 24.86 ± 0.23 24.65 ± 0.22 24.17 ± 0.63 24.97 ± 0.39 10.75 ± 0.19 10.86 ± 0.16 13.08 ± 0.31a 10.90 ± 0.16b 11.55 ± 0.21 11.51 ± 0.11 11.72 ± 0.15 12.02 ± 0.20 10.15 ± 0.03 9.39 ± 0.10 9.02 ± 0.13 9.17 ± 0.04 9.23 ± 0.16 9.33 ± 0.27 9.83 ± 0.14a 9.30 ± 0.07b 4.36 ± 0.06 4.61 ± 0.14 6.31 ± 0.16 6.02 ± 0.12 6.10 ± 0.11a 4.68 ± 0.14b 5.26 ± 0.15b 6.33 ± 0.21a 5.98 ± 0.14 5.76 ± 0.21 6.44 ± 0.25 6.53 ± 0.15 6.40 ± 0.16b 7.99 ± 0.12a 7.24 ± 0.20 7.04 ± 0.12 14 19 24 ab Means of values in the same column within ages with different superscripts are significantly different (p < 0.05) n: Number of observations, DSK: Drumstick, BLT: Body Length, KLT: Keel Length, SLT: Shank Length, CGT: Chest girth, CLT: Comb Length TABLE 2 Table 2 shows the growth traits (mean ± SEM) of Harco-Black cockerels reared at different ages within cage tiers Cage tier Age (Weeks) n DSK (cm) BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) Upper 9 14 19 24 9 14 19 24 20 20 20 20 20 20 20 20 14.65 ± 0.23 b 16.11 ± 0.16 a 15.53 ± 0.17 a 15.86 ± 0.23 a 15.63 ± 0.28 a 15.30 ± 0.15 ab 15.03 ± 0.09 b 15.38 ± 0.13 ab 24.45 ± 0.39 24.13 ± 0.22 24.86 ± 0.23 24.17 ± 0.63 24.20 ± 0.34 24.75 ± 0.32 24.65 ± 0.22 24.97 ± 0.39 10.75 ± 0.19 c 13.08 ± 0.31a 11.55 ± 0.21 b 11.72 ± 0.15 b 10.86 ± 0.16 c 10.90 ± 0.16 c 11.51 ± 0.11 b 12.02 ± 0.20 a 10.15 ±0.03 a 9.02 ± 0.13 b 9.23 ± 0.16 b 9.83 ± 0.14 a 9.39 ± 0.10 9.17 ± 0.04 9.33 ± 0.27 9.30 ± 0.07b 4.36 ± 0.06 c 6.31 ± 0.16 a 6.10 ± 0.11 a 5.26 ± 0.15 b 4.61 ± 0.14 b 6.02 ± 0.12 a 4.68 ± 0.14 b 6.33 ± 0.21 5.98 ± 0.14 b 6.44 ± 0.25 b 6.40 ± 0.16 b 7.24 ± 0.20 a 5.76 ± 0.21 b 6.53 ± 0.15 c 7.99 ± 0.12 a 7.04 ± 0.12 b Lower ab Means of values in the same column within ages with different superscripts are significantly different (p < 0.05) n: Number of observations, DSK: Drumstick, BLT: Body Length, KLT: Keel Length, SLT: Shank Length, CGT: Chest girth, CLT: Comb Length OPEN ACCESS © Research | Reviews | Publications, 2011 http://www.rrpjournals.com/ ISSN 2249-0574 World J Life Sci. and Medical Research 2011;1(3)::63 al., 2011. Growth traits of harco-black cockerel chicken Ojedapo et al Table 3 shows the correlation coefficient among growth OPEN ACCESS from low to high and also there were positive correlation traits of Harco-black cockerels reared at 9 weeks of age than negative. There was a negatively high significance (p within different cage tiers. The correlation shows that < 0.05) between the KLT and BLT and CGT and CLT. A there were more positive relationship than negative. The highly positive significance (p < 0.001) correlation was also relationship between the KLT and SLT, CGT and SLT observed between the DSK and the CLT. A highly were positively low. However, between the CGT and the negatively significant (p < 0.001) correlation exist between DSK, CLT and the SLT were positive relationship than CGT and CLT. negative and these values ranges from low to high. There Table 6 reveals the correlation coefficients among growth was a highly significant (p < 0.01) positive correlation traits of Harco-black cockerels reared at 24 weeks of age between the CGT and the KLT while the relationship within different cage tiers. Generally, the values obtained between CLT and the SLT was positively low. were from low to high. At the lower diagonal, the The correlation coefficients among growth traits of Harco- correlation between the SLT and the DSK was positively black cockerels reared at 14 weeks of age within different high and significant (p < 0.05) while the correlation cage tiers as shown in table 4 shows that at the upper between the CGT and the DSK was negatively high and diagonal depicts a very high negatively significance (p < significant (p < 0.05). At the upper diagonal, the 0.001) between the SLT and the BLT. The DSK and BLT correlation between the SLT and BLT, SLT and KLT were show a low positive relationship while the KLT, BLT and positively high and significant (p < 0.05). The interaction CLT have a positive correlation. between the age and cage tiers shows a very high Table 5 shows the correlation coefficients among growth significance (p < 0.05) correlation in the DSK, KLT, SLT, traits of Harco-Black cockerels reared at 19 weeks of age. CGT and the CLT. Generally, it was observed that the values obtained range TABLE 3 Table 3 shows the correlation (coefficients) among growth traits of Harco-black cockerels reared at 9 weeks of age within different cage tiers Cage tier DSK (cm) DSK (cm) BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) -0.139 -0.164 -0.105 0.382 -0.072 BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) 0.269 -0.423 0.38 -0.415 0.168 -0.143 -0.168 -0.264 0.620** -0.389 -0.362 -0.443 -0.083 0.006 -0.051 0.184 0.087 -0.413 -0.258 0.026 0.144 0.190 0.008 0.404 0.193 Upper diagonal represents 9th week of age, cage tier 2; Lower diagonal represents 9th week of age, cage tier 1; ** (p < 0.001); DSK: Drumstick, BLT: Body Length, KLT: Keel Length, SLT: Shank length, CGT: Chest girth, CLT: Comb length TABLE 4 Table 4 shows the correlation (coefficients) among growth traits of Harco-black cockerels reared at age of 14 weeks within different cage tiers Cage tier DSK (cm) DSK (cm) BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) 0.120 0.174 -0.213 -0.253 0.119 BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) 0.028 0.290 0.431 0.205 0.295 0.399 0.137 -0.296 -0.264 0.296 0.420 -0.518** 0.290 -0.156 -0.293 0.008 -0.069 -0.109 -0.340 -0.119 0.088 0.187 -0.020 0.287 -0.148 Upper diagonal represents 14th week of age, cage tier 2; Lower diagonal represents 14th week of age, cage tier 1; ** (p < 0.001); DSK: Drumstick, BLT: Body Length, KLT: Keel Length, SLT: Shank length, CGT: Chest girth, CLT: Comb length © Research | Reviews | Publications, 2011 http://www.rrpjournals.com/ OPEN ACCESS World J Life Sci. and Medical Research 2011;11(3): (3):64 al., 2011. Growth traits of harco-black cockerel chicken Ojedapo et al OPEN ACCESS ISSN 2249-0574 TABLE 5 Table 5 shows the correlation (coefficients) among growth traits of Harco-black cockerels reared at 19th weeks of age within different cage tiers Cage tier DSK (cm) DSK (cm) BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) -0.278 0.239 0.023 0.177 0.015 BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) -0.80 0.099 -0.477* 0.130 -0.313 0.263 -0.380 -0.34 0.301 -0.210 0.700** 0.043 -0.029 0.329 -0.699** -0.267 0.232 0.102 -0.022 0.090 0.203 0.108 0.113 -0.108 -0.093 Upper diagonal represents 19th week of age, cage tier 2; Lower diagonal represents 19th week of age, cage tier 1; ** (p < 0.001); DSK: Drumstick, BLT: Body Length, KLT: Keel Length, SLT: Shank length, CGT: Chest girth, CLT: Comb length TABLE 6 Table 6 shows the correlation (coefficients) among growth traits of Harco-black cockerels reared at 24 weeks of age within different cage tiers Cage tier DSK (cm) DSK (cm) BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) 0.179 0.159 0.553* -0.493* 0.008 BLT (cm) KLT (cm) SLT (cm) CLT (cm) CGT (cm) 0.012 0.401 0.191 -0.068 0.490* 0.467* 0.127 0.216 0.135 -0.013 0.094 -0.030 0.285 0.426 -0.270 0.009 0.102 0.106 0.154 -0.148 0.104 -0.087 -0.359 0.285 0.183 Upper diagonal represents 24th week of age, cage tier 2; Lower diagonal represents 24th week of age, cage tier 1; ** (p < 0.001); DSK: Drumstick, BLT: Body Length, KLT: Keel Length, SLT: Shank length, CGT: Chest girth, CLT: Comb length DISCUSSION physiological The significant effect of cage tier on some of the growth majority of the growth traits obtained at advanced ages of traits is an indication that DSK, KLT, SLT, CGT and CLT the birds in both tiers are reasonable because the feed responded positively to the upper tier of the cage used in intake and conversion efficiency of birds had gone up at rearing. Cage density plays a major role in determining this period. the well being of birds. [12] reported that greater stocking Generally density reduces feed intake and reduce body weight. In coefficients amongst the growth traits at all ages agrees addition, the higher values obtained at the upper tier with past literatures of Ojedapo et al. [16]. This positive generally be correlation suggests that these traits are under the same recommended for the rearing of cockerels. This agrees gene action and by implication selection for improvement with the reports of Carmichael et al. [13] who discovered in one trait would bring about a corresponding higher performance with the birds reared at upper tier improvement in the other traits on a correlated response. showed that the upper tier could development. the pattern of The highest variation of values of correlation cage. This result might be due to the fact that the cockerels at the lower tier were unavoidably more exposed to the ammonia gas coming from their droppings which might CONCLUSION invariably interfere with their metabolic processes. The result revealed higher values at the upper tier which The significant variations in the growth traits as age of the shows that the upper tier could be recommended for the birds advanced both in the upper and lower theirs agrees rearing of cockerels between fourteen and twenty weeks with reports of Sonaiya et al. [14] and Pingel et al. [15] that of age. This result might be due to the fact that the age is also a major factor affecting of growth rate and cockerels at the lower tier were unavoidably more OPEN ACCESS © Research | Reviews | Publications, 2011 http://www.rrpjournals.com/ ISSN 2249-0574 World J Life Sci. and Medical Research 2011;1(3)::65 al., 2011. Growth traits of harco-black cockerel chicken Ojedapo et al exposed to the ammonia gas coming from their droppings [9] [10] British American Tobacco Company, meteorological site. Ogbomoso. Nigeria 2004. upper tier for rearing harco black cockerels chicken between fourteen and twenty weeks of age. Alternatively Obioha FC. A guide to poultry production in the tropics. Arenna publishing, Lagos, Nigeria. 1992. which might be interfering with some of their metabolic processes. Therefore, it could be preferable to use the OPEN ACCESS [11] Statistical Analysis System, user’s guide. Version persistent (very frequent) replacement of litters and 9.2, Statistical Analysis System. institutes inc. Cary evacuation of the dropping should be done, but this may no. 27513.UK. 2009. attract extra-cost [12] Carey VB. Effects of pullet stocking density on performance of laying hens. Poultry Science 1987;66:1283-7. REFERENCES [1] [2] [13] Sainsbury D. 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