Summary The purpose of this paper is to determine the effects of four genotypes and four different quantitative feeding regimes on the post-weaning average feed intake (AFI), body weight (BW), weight gain (WG) and feed conversion ratio (FCR) of 48 unsexed weaner rabbits. At weaning, a total of 3 rabbits from each genotype considered, namely the purebred Chinchilla and New Zealand White (CH x CH, NZW x NZW) and their reciprocal crossbreds (CH x NZW, NZW x CH), were randomly assigned to four feeding regimes: ad libitum concentrate + ad libitum forage (A), ad libitum concentrate + 30% restricted forage (B), 30% restricted concentrate + ad libitum forage (C), and 30% restricted concentrate + 30% restricted forage (D). The data were subjected to a two-way analysis of variance in a completely randomized design appropriate for a 4x4 factorial experiment. The experiment was conducted over a period of 5 weeks: from 7 to 11 weeks post-weaning. The AFI values obtained from the interactions between CH x CH and the C feeding regime at 7 weeks post-weaning (366.50 ± 1.50 g), and between NZW x NZW and the B feeding regime at 8 weeks (324.00 ± 1. 00 g) and 10 weeks post-weaning (336.50 ± 0.00 g) were similar, but differed significantly (P < 0.05) from the rest. The lowest significant AFI values (P < 0.05) at all ages and FCR values (3.46 ± 0.33) at 9 weeks post-weaning were obtained from NZW x NZW, whereas the highest BW values at 9-11 weeks post-weaning was obtained from CH x CH. The lowest significant AFI values (P < 0.05) were recorded in the B feeding regime at 7-11 weeks post-weaning, as well as the highest BW and WG values in the A feeding regime at 8–11 and 11 weeks post-weaning, respectively. Moreover, the highest significant BW values (781.25 ± 7.83) were recorded in the C feeding regime at 7 weeks post-weaning. It was concluded that the interactions between CH x CH and the C feeding regime and between NZW x NZW and the B feeding regime can significantly reduce the overall feed intake, thus invariably increasing profit in rabbit production.

The study evaluated the effect of strain on productive traits of three broiler chickens. A total of 144 broilers, 48 each of Hubbard, Marshall and Ross were used for the experiment which lasted 8 weeks. The birds were reared in separate deep litter pens with each strain replicated into 4 having 12 birds per replicate. Data were generated on body weight and linear body parameters (body length–BL, kneel length–KL, shank length–SL, wing length–WL,breast width–BSW, thigh length TL and drum stick length DL) at 2weeks interval from the 2week, growth performance, carcass and economics of production indices. Data were analyzed using the general linear model procedure of SPSS package. Results obtained showed significant (p<0.05) differences among the strains for the various parameters studied.The Marshall strain was significantly (p<0.05) superior in final body weight(1861.14g) followed by Ross (1714.44 g) while the least in body size was Hubbard (1432.45 g). Daily weight gain (g/bird/day) and FCR were significantly (p<0.05) better in Marshall and Ross compared to Hubbard. Marshall and Ross strain had significantly(p<0.05) heavier body weights and longer bodies in week 28; longer keels(week 6 and 8), thighs(week 2 and 6) and drumsticks (weeks 2, 6 and 8). Hubbard and Marshall showed statistically (p<0.05) higher mean values for BSW than Ross in weeks 2 and 4. For the carcass traits, Marshall broiler also showed superiority (p<0.05) over Ross and Hubbard in live weight 1818.75 vs 1653.13, 1500.00 g), defeathered weight (1643.75 vs 1487.50, 1375.00g), dressed weight (1359.39 vs 1280.00,1062.50g) and percent breast 18.44 vs 16.95,13.95). However, Rossand Hubbard had higher (p<0.05) means for shank proportion than for Marshall. Results of the cost-benefit indices revealed that the Marshall strain significantly (p<0.05) generated more revenue (₦1460.91/bird) and gross profit (₦666.52/bird) compared to its counter part strains. Marshall could therefore be recommended to farmers in our study area as a choice strain with faster growth and superior carcass yield for maximum economic return.

Indigenous chickens have some peculiarity that enables them withstand harsh weather, resistance to diseases and adaptive mechanism to the environment. However, the indigenous chickens have some disadvantages arising from rearing mortality, slow growth rates, poor egg production and attains sexual maturity late. Such birds can be improved genetically through selective breeding. The study was aimed at accessing the growth performance of Isa Brown (exotic) x Normal Local chicken progenies in a humid tropical region. Ten commercial strain (Isa Brown female) and two Normal Local Chicken (NLC), housed in ratio 1:5 and mated through natural and artificial insemination which produced 90eggs, out of which 54 eggs hatched. The hybrids were managed under an intensive system, randomly divided and allotted into six replicates with nine birds each for eight weeks. Data were collected for feed and growth parameters, linear body measurements and analyzed using Statistical Software for Social Scientists (SPSS). Significant (P<0.05) differences were observed for all the weeks for body weight, body length, shank length, body girth, wing length and keel length. The result revealed an increasing order from week 1 to week 8 as expected, with the 8th   week having the superior mean value for body weight (463.45g), body length (17.71cm), shank length (11.77cm), body girth (20.87cm), wing length (15.98cm) and keel length (10.64cm). Also, there were significant (P<0.05) differences in feed efficiency and growth parameters for all the weeks; feed efficiency and daily weight gain increased from week 1 to week 3 (5.29%, 12.40%, 14.41%) and (1.50%, 4.68%,5.65%), respectively. Feed conversion ratio was high at week 1 (18.92%) of the experiment while other weeks recorded similar mean values. There were significant (P<0.05) differences for feed intake across the weeks. Result from carcass evaluation of the hybrids showed that back weight (16.44%/DWT) and breast weight (16.05%/DWT) constitutes major meat portions, followed by wing weight (9.70%/DWT) and drumstick (9.10%/DWT) while the heart (0.59%/DWT) constituted the least portion. Significant (P<0.05) positive correlations were observed for all the correlating parameters at 4th and 8th weeks; as all the parameters ranged from 0.934 to  0.975 and 0.907 to 0.964 at 4th and 8th   weeks respectively. Furthermore, the adaptability of the normal local chicken masked or outperformed that of the exotic breed. However, discussion of this present study has revealed that the progenies of the crosses has more characteristic features of a layer than a meat type chicken.       Les poulets indigènes ont une particularité qui leur permet de résister aux intempéries, de résister aux maladies et de s'adapter à l'environnement. Cependant, les poulets indigènes présentent certains inconvénients liés à la mortalité d'élevage, aux taux de croissance lents, à la faible production d'œufs et à la maturité sexuelle tardive. Ces oiseaux peuvent être améliorés génétiquement par un élevage sélectif. L'étude visait à accéder aux performances de croissance des descendances de poulet Isa Brown (exotique) x Normal Local dans une région tropicale humide. Dix souches commerciales (femelle Isa Brown) et deux poules locales normales (PLN), hébergées dans un rapport de 1: 5 et accouplées par insémination naturelle et artificielle qui ont produit 90 œufs, dont 54 œufs ont éclos. Les hybrides ont été gérés selon un système intensif, divisés au hasard et répartis en six répétitions avec neuf oiseaux chacune pendant huit semaines. Les données ont été recueillies pour les paramètres d'alimentation et de croissance, les mesures corporelles linéaires et analysées à l'aide du logiciel statistique pour les scientifiques sociaux (SPSS). Des différences significatives (P<0,05) ont été observées pour toutes les semaines pour le poids corporel, la longueur du corps, la longueur de la tige, la circonférence du corps, la longueur des ailes et la longueur de la quille. Le résultat a révélé un ordre croissant de la semaine 1 à la semaine 8 comme prévu, la 8e semaine ayant la valeur moyenne supérieure pour le poids corporel (463,45 g), la longueur corporelle (17,71 cm), la longueur de la tige (11,77 cm), la circonférence corporelle (20,87 cm), la longueur de l'aile (15,98 cm) et la longueur de la quille (10,64 cm). De plus, il y avait des différences significatives (P < 0,05) dans l'efficacité alimentaire et les paramètres de croissance pour toutes les semaines ; l'efficacité alimentaire et le gain de poids quotidien ont augmenté de la semaine 1 à la semaine 3 (5,29 %, 12,40 %, 14,41 %) et (1,50 %, 4,68 %, 5,65 %), respectivement. Le taux de conversion alimentaire était élevé à la semaine 1 (18,92 %) de l'expérience tandis que les autres semaines enregistraient des valeurs moyennes similaires. Il y avait des différences significatives (P< 0,05) pour l'apport alimentaire au fil des semaines. Le résultat de l'évaluation de la carcasse des hybrides a montré que le poids du dos (16,44 %/DWT) et le poids de la poitrine (16,05 %/DWT) constituent les principales portions de viande, suivis du poids des ailes (9,70 %/DWT) et du pilon (9,10 %/DWT) tandis que le cœur (0,59 %/DWT) constituait la moindre portion. Des corrélations positives significatives (P<0,05) ont été observées pour tous les paramètres de corrélation aux 4e et 8e semaines ; car tous les paramètres variaient de 0,934 à 0,975 et de 0,907 à 0,964 aux 4e et 8e semaines respectivement. De plus, l'adaptabilité du poulet local normal masquait ou surpassait celle de la race exotique. Cependant, la discussion de cette présente étude a révélé que les descendants des croisements ont plus de traits caractéristiques d'une couche qu'un poulet de type viande.

Correlation coefficients are useful tool in animal breeding as a means of predicting potential response. In this study, body weight (BW) and linear body traits records of Arbor Acre and Cobb broiler strains obtained at 3 – 8 weeks were used to compare the growth performance of the strains as well as estimate the phenotypic correlations (rp ) among BW and the linear body traits. Repeatability (R) values of BW and the linear body traits were estimated at weeks 3, 5 and 7. Atotal of 200 day old chicks, 100 each of Arbor Acre and Cobb were used for the study. The linear body traits considered were body length (BL), shank length (SL), chest circumference (CC), keel length (KL), wing length (WL) and drum stick length (DSL). Significant differences (P<0.05) were observed between the strains for BW and the linear body traits at the various weeks. BW differed significantly at weeks 5, 6 and 7, which ranged from 1036.67 ± 36.93 – 1736.67 ± 46.41 for Arbor Acre and 930.00 ± 20.59 – 1563.33 ± 33.26 for Cobb. Arbor Acre showed significant (P<0.05) superiority to Cobb in their linear body traits in most of the weeks. BW had high significant (P<0.05; P<0.01) positive rp with the linear body traits, which ranged from 0.535 (KL) – 0.842 (BL) for Arbor Acre and 0.523 (SL) – 0.834 (BL) for Cobb. The rp among the linear body traits in both Arbor Acre and Cobb were positive but ranged from moderate to high. The R estimate of BW of Arbor Acre and Cobb were all very highly repeatable at weeks 3, 5 and 7 ranging from 0.90 – 0.99. R values for the linear body traits ranged majorly from moderate {(0.31 – 0.67 and 0.37 – 0.69)}to high {(0.78 – 0.97) and 0.97) and (0.71 – 0.92)} for Arbor Acre and Cobb, respectively across the weeks evaluated. The result of this study indicates that Arbor Acre could be a strain of choice for rearing in our study area owing to its superiority over Cobb in terms of growth performance. All the linear body traits measure were good estimators of BW in both strains as well as each other, implying that any phenotypic selection on one trait will lead to improvement of others. The high repeatability estimates of body weight and some of the linear traits indicate that fewer records would be required to adequately characterize the inherent growing ability of the birds at the various stages of growth.

A total of 270 pedigreed-hatched day old chicks of three strains of Japanese quail generated from a base population of 36 adultswere used in a randomized complete block design to estimate the influence of sire on the internal egg quality and linear body traits of the birds. Parameters measured were internal egg quality traits - albumen height, yolk height, albumen weight, yolk weight, albumen diameter, albumen length, yolk width, yolk length, yolk index, and haugh unit, and growth traits - body weight, thigh length, breast length, body length, keel length, wing length, and shank length. Results showed that linear bodyparameters were significant (P<0.05) except body weight at week 9. Panda white x Cinnamon brown (PWxCB) progenies out-performed the progenies of the other strains mainly at week 9. The PWxCB strain had the highest values in the following: body weight (159.30), thigh length (4.76), breast width (7.40), body length (11.94), keel length (6.77), and shank length (3.44). The haugh unit value was significantly (P< 0.05) different among the three strains mainly at week 8 with CBxCB strain having higher value of (89.07) followed by PWxCB strain (89.03). The phenotypic correlations between the linear body parameters andinternal egg quality traits in Cinnamon brown x Cinnamon brown (CBxCB) strain were significant (P<0.01) in keel length and yolk weight (0.534) and between shank length and yolk weight (0.473) at week 9. For PWxCB strain, high significant (P<0.01) correlation were seen between shank lengthand albumen length (0.631) at week 8, body weight and yolk index at week 9. Silver brown x Cinnamon brown (SBxCB) strain also showed high positive significant (P<0.01) correlation between shank length and yolk weight (0.541), breast width and albumen weight (0.537) and between body length and albumen weight (0.625) at week 9.These positive correlations imply that by direct selection for any linear body trait for increased meat production, there will be a remarkable genetic improvement in the internal egg quality trait. It can be concluded that PWxCB is a strain of choice for improved growth and internal egg quality characteristics.