Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-01-06T13:28:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) graziela_taroco.pdf: 2989194 bytes, checksum: a96e95e60ba666acde3399249ccd46f0 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-01-31T16:59:07Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) graziela_taroco.pdf: 2989194 bytes, checksum: a96e95e60ba666acde3399249ccd46f0 (MD5) / Made available in DSpace on 2017-01-31T16:59:07Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) graziela_taroco.pdf: 2989194 bytes, checksum: a96e95e60ba666acde3399249ccd46f0 (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Em esp?cies de interesse zoot?cnico as caracter?sticas de import?ncia econ?mica, como o crescimento dos animais, podem apresentar diferen?as produtivas as quais s?o atribu?das ? influ?ncia dos efeitos gen?ticos e ambientais. Desta forma, a intera??o gen?tipo-ambiente pode ocasionar mudan?as nas vari?ncias dos valores gen?ticos e/ou na classifica??o destes animais. Objetivou-se com o presente trabalho estimar curvas de crescimento de codornas de corte, dos grupos gen?ticos LF1 e LF2, alimentadas com diferentes rela??es de treonina:lisina na dieta, por meio dos modelos Gompertz, Log?stico, Richards e von Bertalanffy, bem como predizer os par?metros gen?ticos da curva de crescimento para peso corporal aos 35 dias de idade, peso assint?tico, taxa de crescimento absoluto e ponto de inflex?o e avaliar a exist?ncia de intera??o gen?tipo ? ambiente para a express?o destas caracter?sticas. Na primeira fase do experimento, do nascimento aos 21 dias de idade, as codornas foram alimentadas com dietas contendo rela??es 0,66, 0,71, 0,76, 0,81 e 0,86% de treonina:lisina. Dos 22 aos 35 dias de idade, as codornas receberam dieta ?nica contendo 26,12% de prote?na bruta e 2.900 kcal EM/kg. Na segunda fase, as codornas foram alimentadas com dieta ?nica contendo 24,54% de prote?na bruta e 2.900 EM/Kg, do nascimento aos 21 dias de idade. Dos 22 aos 35 dias de idade as codornas foram alimentadas com dieta contendo rela??es de 0,71, 0,76, 0,81, 0,86 e 0,91% de treonina:lisina. Os diferentes modelos de curva de crescimento foram ajustados e as intera??es foram avaliadas por meio de modelos de regress?o aleat?ria, considerando-se os efeitos fixos de sexo e os efeitos aleat?rios gen?ticos aditivos diretos como fun??es dos n?veis da rela??o treonina:lisina da dieta. Os resultados demonstraram que o modelo Gompertz proporcionou melhor ajuste da curva de crescimento das codornas de corte. As estimativas de herdabilidade foram de moderadas a alta ao longo das rela??es treonina:lisina. As normas de rea??o demonstram a exist?ncia de intera??o gen?tipo ? ambiente para as rela??es treonina:lisina da dieta e, em decorr?ncia disto, ocorrem altera??es na dispers?o dos valores gen?ticos ou na ordem de classifica??o dos m?ritos gen?ticos das codornas. Desta forma, os programas de melhoramento de codornas devem considerar os n?veis de treonina:lisina na dieta das aves, uma vez que esta pode interferir no desempenho dos animais. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / Traits of economic interest in livestock species, such as growth, may have productive differences which are attributed to the influence of genetic and environmental effects. Thus, the genotype-environment interaction may lead to changes in the genetic values variances and / or consequently in the ranking of animals. In this study, we aimed at estimating growth curves for quails from two genetic groups, LF1 and LF2, fed with different threonine: lysine ratios in the diet. The non-linear models tested were Gompertz, Logistic, Richards and von Bertalanffy. We also aimedt at predicting genetic parameters for the growth curve for body weight at 35 days of age, asymptotic weight, absolute growth rate and inflection point and assess the existence of genotype ? environment interaction for the expression of these traits. In the first phase of the experiment, from birth to 21 days of age, quails were fed with diets containing 0.66, 0.71, 0.76, 0.81 and 0.86% of threonine: lysine ratio. From 22 to 35 days of age, quails received a diet containing 26.12% of crude protein and 2,900 kcal / kg. In the second phase, the quails were fed only with a diet containing 24.54% of crude protein and 2,900 ME / kg, from birth to 21 days old. From 22 to 35 days old quails were fed with diets containing 0.71, 0.76, 0.81, 0.86 and 0.91% of threonine: lysine ratio. The different growth curve models were adjusted and interactions were assessed by random regression models, considering the fixed effect of sex and the random effect of direct genetic additive effect, both as functions of the threonine:lysine ratio. The results showed that the Gompertz model provided the best fit for the growth curve of these quails. The heritability estimates were moderate to high for all the threonine: lysine ratios. The reaction norms demonstrated the existence of genotype - environment for threonine:lysine diet and, as a result, changes may occur in the breeding values or sort ordering for the genetic merit of the quails. Therefore, breeding programs must consider the levels of threonine: lysine in the diet of the quails, since it may interfere with the performance of the animals.