Carcass yield of meat quails in diallel cross

Objetivou-se com este trabalho avaliar o peso e rendimento de carca?a e cortes de codornas por meio da metodologia de cruzamentos dial?licos. Foram utilizadas quatro linhagens de codornas de corte, denominadas L1, L2, L3 e L4. O sistema de cruzamento proporcionou 16 grupos de prog?nies, sendo quatro parentais (puros), seis mesti?os F1 e seis mesti?os F1 rec?procos, alojadas em bateria experimental em tr?s repeti??es. Aos 42 dias de idade, cinco machos de cada unidade experimental foram escolhidos ao acaso e destinados ao abate, para avalia??o do peso aos 42 dias de idade, peso e rendimento de carca?a, do peito, das pernas e das asas. A an?lise dial?lica foi desenvolvida de forma univariada, considerando-se a metodologia de dialelos completos, incluindo as p? combina??es das linhagens, a partir das m?dias das combina??es genot?picas. As an?lises de capacidade combinat?ria mostraram signific?ncia para capacidade geral de combina??o (CGC) para peso corporal, da carca?a, peito, pernas e asas, enquanto a capacidade espec?fica de combina??o (CEC) foi significativa apenas para o peso e rendimento de pernas. Os quadrados m?dios da CGG apresentaram, de forma geral, valores maiores que da CEC, revelando a predomin?ncia de efeitos aditivos na express?o dessas caracter?sticas, o que indica que melhorias nestas caracter?sticas podem ser conseguidas por meio de processos de sele??o intrapopulacional. As linhas L1, L2 e L4 apresentaram valores positivos para CGC em praticamente todas as caracter?sticas avaliadas, e podem ser consideradas superiores ? m?dia das linhagens envolvidas no dialelo, sendo, portanto, favor?veis para proporcionarem aumento nas caracter?sticas avaliadas. Foi observado maior efeito dos genes aditivos, indicando que a sele??o das linhas puras pode trazer ganhos satisfat?rios, sendo a linha L2 a mais promissora, com base em sua capacidade geral de combina??o. Para peso de pernas, o cruzamento L2xL4 seria o mais indicado e, para o rendimento de pernas, o cruzamento L1xL4, com base na capacidade espec?fica de combina??o.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)This study aimed to evaluate the weight and carcass yield and cuts of meat quails through the methodology of diallel crosses. It was used four strains of meat quails, named L1, L2, L3 and L4. The mating system provided 16 groups of progenies, four parents (pure), six F1 crossbred and six F1 reciprocal crossbred, allocated in experimental batteries in three replicates. On the day 42th day of life, five males from each experimental unit were randomly chosen and destined for slaughter, to evaluate weight, weight and production of carcass, chest and legs; and wings yield. The diallel analyses were developed using univariate analysis, considering the methodology of complete diallel, including p? combinations, from the average of the genotype combinations. The analyses of combining ability showed significance for general combining ability (GCA), body weight, carcass weight, breast meat, legs and wings, while specific combining ability (SCA) was significant only for the weight and leg yield. The mean squares of GCA were, in general, higher values than SCA ones, showing the prevalence of additive effects on expression of these traits, indicating that these improved traits can be achieved through the selection process. The lines L1, L2 and L4 showed positive GCA values in almost all traits evaluated, and can be considered above the average of the lines involved in diallel; therefore, provide the most favorable for increasing the assessed traits. It was observed a greater additive effect of genes, suggesting that the selection of inbred lines can bring satisfactory gains, being the line L2 the most promising, based on their general combining ability. For legs' weight crossing L2xL4 would be more appropriate, and for legs yield, crossing L1xL4, based on specific combining ability

Detoxified Castor Seed Cake for Broilers

Abstract The objective of the present study was to evaluate the effect of the dietary detoxified castor seed cake (DCC) inclusion on broiler performance and carcass traits. Two hundred and fifty Cobb-500(r) broilers were distributed according to a completely randomized experimental design consisting of five treatments (dietary inclusion of 0.0, 2.5, 5.0, 7.5, and 10.0% DCC) with five replicates of 10 birds each (five males and five females). Feed intake (FI), body weight gain (WG), and feed conversion ratio (FCR) were evaluated from one to 40 days of age. Carcass yield and the yields of the breast, leg (drumstick+thighs), and wings were determined when broilers were 40 days old. Live performance parameters were influenced by DCC dietary inclusion, and levels 2.00, 1.38, and 1.25% DCC impaired FI, WG, and FCR, respectively. Carcass and parts yields were not affected by dietary DCC inclusion. It was concluded that the addition of DCC levels up to 1.25% to broiler diets does not impair live performance or carcass traits

Classification of coefficients of variation in experiments with commercial layers

This study aimed at determining a specific classification of coefficients of variation in experiments with commercial layers. Coefficients of variation were collected from papers published in Brazilian journals between 2000 and 2009 for performance, internal egg quality, and eggshell quality parameters. The coefficients of variation of each parameter were classified as low, intermediate, high, and very high according to the ratio between the median and the pseudo-sigma. It was concluded that the parameters used in experiments with commercial layers have a specific classification of coefficients of variation, and that this must be considered to evaluate experimental accuracy