Objetivou-se nesta pesquisa determinar as faixas de conforto térmico, avaliadas em termos de temperatura e Índices de Temperatura de Globo Negro e Umidade (ITGU), adequadas à criação de codornas de corte na fase final de criação. Foram alojadas 300 codornas de corte, em diferentes ambientes térmicos. Cada grupo de 60 aves foi distribuído, aleatoriamente, em 03 câmaras climáticas, sendo 10 aves por unidade experimental (gaiola), totalizando 15 tratamentos. Os tratamentos foram: CP - Conforto Preconizado (temperaturas de 26 e 25 oC, respectivamente, para quarta e quinta semana de criação); QM - Calor Moderado (30 oC para a quarta e quinta semana de criação) e QS - Calor Severo (33 oC para a quarta e quinta semana de criação). Durante a quarta semana de criação das codornas (22 a 28 dias), o melhor valor de ITGU foi de 75,8 ± 0,9 e para a quinta semana de criação (29 a 35 dias) ITGU de 75,3 ± 0,7 (indicativos de conforto térmico para esta idade). Verificou-se que: codornas mantidas em estresse térmico (seja por frio ou calor) durante a fase inicial de criação não se recuperam ao final do ciclo de vida; mesmo quando criadas em condições de conforto térmico na fase inicial, após este período, quando mantidas em temperaturas de estresse seja por calor moderado ou severo crônicos, não conseguem se manter com a performance normal, demonstrando a necessidade de se garantir que o ambiente térmico dos aviários seja mantido adequado de acordo com as exigências para cada idade das codornas.
This work aimed to determine which non-linear model (Brody, Gompertz, logistic, von Bertalanffy or Richards) best represents the average growth curve of goats, in addition to evaluating the effect of the environment. The weight data of 40 Repartida goats reared in the Brazil Caatinga were included in this study. Weight data was collected every 30 days from birth until 270 days of age. The parameters of the models (A, mature body weight; B, constant of integration; k, maturation rate; m, inflection point) were estimated using the NLIN procedure of SAS. The logistic model showed a slightly higher average fit in comparison to the other models. The absolute growth rate suggests that the maximum growth rate was reached early. The effect of the contemporary groups was significant (P < 0.05), but only for the estimated k parameter. The estimated correlation between the A and k parameters was significant and negative, indicating a lower probability of a high body weight in adulthood. Goats of the Repartida ecotype are characterized by their high birth weight and low weight at maturity, which combined with the nutritional deficit, suggests that these animals have adapted to the adverse conditions of the Brazilian Caatinga region.
The objective of this study is to compare random-regression models used to describe changes in evaluation parameters for growth in Tabapuã bovine raised in the Northeast of Brazilian. The M4532-5 random-regression model was found to be best for estimating the variation and heritability of growth characteristics in the animals evaluated. Estimates of direct additive genetic variance increased with age, while the maternal additive genetic variance demonstrated growth from birth to up to nearly 420 days of age. The genetic correlations between the first four characteristics were positive with moderate to large ranges. The greatest genetic correlation was observed between birth weight and at 240 days of age (0.82). The phenotypic correlation between birth weight and other characteristics was low. The M4532-5 random-regression model with 39 parameters was found to be best for describing the growth curve of the animals evaluated providing improved selection for heavier animals when performed after weaning. The interpretation of genetic parameters to predict the growth curve of cattle may allow the selection of animals to accelerate slaughter procedures.
The aim was to analyze variation in 12 Brazilian and Moroccan goat populations, and, through principal component analysis (PCA), check the importance of body measures and their indices as a means of distinguishing among individuals and populations. The biometric measurements were wither height (WH), brisket height (BH) and ear length (EL). Thorax depth (WH-BH) and the three indices, TD/WH, EL/TD and EL/WH, were also calculated. Of the seven components extracted, the first three principal components were sufficient to explain 99.5% of the total variance of the data. Graphical dispersion by genetic groups revealed that European dairy breeds clustered together. The Moroccan breeds were separated into two groups, one comprising the Drâa and the other the Zagora and Rhâali breeds. Whereas, on the one side, the Anglo-Nubian and undefined breeds were the closest to one another the goats of the Azul were observed to have the highest variation of all the breeds. The Anglo-Nubian and Boer breeds were similar to each other. The Nambi-type goats remained distinct from all the other populations. In general, the use of graphical representation of PCA values allowed to distinguish genetic groups.
Neste trabalho, objetivou-se estimar os parâmetros da equação de intensidade, duração e frequência de chuvas máximas (IDF) para 335 estações pluviométricas do Estado do Rio Grande do Norte. Os dados pluviométricos de cada estação foram obtidos do banco de dados da Agência Nacional de Águas. Para estimar as precipitações máximas de cada estação e período de retorno (5, 10, 15, 25, 50 e 100 anos), foram utilizadas as seguintes distribuições de probabilidade: Gumbel; Log-Normal II; Log-Normal III; Pearson III; Log-Pearson III. Após a estimativa das precipitações máximas, foi realizada a desagregação das precipitações em menores intervalos de tempo. A regressão múltipla não linear para estimativa dos parâmetros (K, a, b e c) foi realizada pelo método de interação de Gradação Reduzida Generalizada Não Linear. Ao final, obteve-se a estimativa dos parâmetros (K, a, b e c) da IDF para 101 estações, com R2 superiores a 0,98 para a maioria das cidades do estado do Rio Grande do Norte.
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