Crescimento de genótipos de frangos tipo caipira / Growth of genotypes of an alternative strain of broiler chickens

Objetivou-se com este trabalho comparar o padrão de crescimento, mediante ajustes das respectivas curvas de crescimento por modelos não lineares, bem como estudar o desenvolvimento de cortes de carcaça em relação ao peso da carcaça em diferentes genótipos de frangos tipo caipira. Foram utilizados 840 pintos de um dia, machos, distribuídos em delineamento inteiramente ao acaso, dos seguintes genótipos da linhagem Redbro: Caboclo, Carijó, Colorpak, Gigante Negro, Pesadão Vermelho, Pescoço Pelado e Tricolor. As aves foram alojadas em 28 boxes, sendo 30 aves/boxe, em galpão de alvenaria com acesso a um piquete de 45m², com quatro repetições. O peso corporal individual dos frangos foi medido ao nascer, aos 14, 28, 42, 56, 70 e 84 dias de idade. Para a determinação das curvas de crescimento do peso corporal das aves, os dados coletados foram avaliados por meio dos modelos não lineares: Brody, Gompertz, Logístico, Richards e von Bertalanffy. Foi empregado o PROC NLIN do SAS, utilizando-se o método interativo de Gauss-Newton. Os critérios usados para escolha do modelo de melhor ajuste da curva de crescimento foram o coeficiente de determinação, o desvio padrão assintótico, o desvio médio absoluto dos resíduos e o índice assintótico. As análises para obtenção dos coeficientes alométricos foram realizadas por meio do PROC GLM do SAS para os genótipos Carijó, Colorpak, Pesadão Vermelho, Pescoço Pelado e Tricolor. Foram avaliados os pesos da carcaça, do peito, das coxas, das sobrecoxas, das pernas e das asas das aves abatidas aos 85 dias de idade. Apenas as equações propostas por Gompertz, von Bertalanffy e Logístico atingiram a convergência, e o modelo proposto por von Bertalanffy foi o mais adequado para descrever o crescimento dos genótipos de frangos caipiras. Todos os cortes avaliados apresentaram crescimento tardio em relação ao peso da carcaça em genótipos de frangos tipo caipira.

The aim of this work was to compare the growth pattern, adjusting the growth curves by nonlinear models and studying the development of housing sections in relation to the weight of the chicken carcass in different genotypes of an alternative strain of broiler chickens. We used 840 one day old male chicks distributed in a completely randomized design, with the following genotype strains: Redbro: Caboclo, Carijó, Colorpak, Gigante Negro, Pesadão Vermelho, Pescoço Pelado and Tricolor. The birds were housed in 28 boxes, 30 birds / box in a masonry shed with access to a 45 square meter paddock, with four replications. Body weight was measured in chickens up to 84 days of age. To determine the growth curves of the body weight of birds, collected data were evaluated from the nonlinear models: Brody, Gompertz, Logistic, Richards and von Bertalanffy. Was used "proc nlin" of SAS, using the iterative method of Gauss-Newton. The criteria used to choose the best model for the growth curve were the coefficient of determination, the asymptotic standard deviation, the mean absolute deviation of the waste and the asymptotic index. The analysis to obtain the allometric coefficients were performed using the "proc glm" SAS for genotypes Carijó, Colorpak, Pesadão Vermelho, Pescoço Pelado and Tricolor. We assessed the weights of carcass, breast, thighs, drumsticks, legs and wings. Only the equations proposed by Gompertz, Logistic and von Bertalanfy reached convergence, and the model proposed by von Bertalanffy was the most appropriate. All sections were evaluated in relation to the late growth of carcass weight in alternative lines of broiler chickens.

Egg laying and egg quality in meat type quails in diallel crosses.

This study aimed to assess egg laying and egg quality in quail lines in diallel crosses. We evaluated 16 genetic groups obtained from crosses of four strains of meat quails (L1, L2, L3, and L4) in a complete diallel. We assessed weekly egg number (WEN), egg yield (EY), egg weight (EW), and Haugh unit (HU) for: 51-80, 81-110, 111-140, and 51-140 days (whole period) old. The general combining capacity (GCC) showed significance for WEN and EY, with the exception of the period of 111-140 days. In general, L3 had the highest positive GCC estimates. The additive genetic variability was significant for EW in all periods, as was HU, with the exception of the first period. The specific combining capacity was significant for HU, except in the second period. The largest estimates for GCC were submitted by L1 for EW, followed by L4, considering the whole period. For HU, L2 had the highest estimates for GCC. The more favorable cross for HU was L2xL3, in the whole period. In the third period, there was a significant reciprocal effect, where there was a positive estimate for the cross L2xL3.