La fecundidad efectiva en la República Argentina, según algunas características de la madre

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Composición de la población según características demográficas y sociales

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Características morfogênicas e estruturais de híbridos de sorgo submetidos a adubação nitrogenada

The effect of two topdressing nitrogen doses was evaluated on the morphogenetic and structural characteristics of sorghum hybrids (Sorghum bicolor (L.) Moench) BRS 801 and 0734006, cultivated in vases in open-air conditions. A completely randomized design was used with four treatments arranged in factorial outline 2x2 (two sorghum hybrids and two nitrogen doses, 50 and 100 kg ha-1), with eight replications per treatment. There was a significant effect of interaction hybrid x fertilization on the leaf appearance rate, the hybrid BRS 801 being more responsive to the increased nitrogen dose. The phyllochron, the total number of leaves and leaf elongation rate, were influenced both by nitrogen doses and by hybrids. The leaf senescence rate was not influenced by factors fertilization and hybrids. These variations in morphogenetic and structural characteristics between the hybrids and/or nitrogen doses, probably indicate that hybrids respond in a different way to topdressing.

Características y nivel de vida de los ancianos en Costa Rica

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Estudio experimental sobre la mortalidad y algunas características socioeconómicas de las personas de la tercera edad: informe de la investigación efectuada en los cantones de Puriscal y Coronado, 3-20 junio 1985

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La incidencia de las características de los empresarios en el desarrollo de las PYMEs: el caso de la metalmecánica en el Gran Buenos Aires

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Las organizaciones de barrio de la tercera edad en Buenos Aires: características y alcances

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Características demográficas, de empleo y de composición familiar en Puerto Rico

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Banco de Proyectos de Inversión Nacional: características y resultados del proyecto: informe final

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Características y estructura del sistema computacional del Banco de Proyectos de Inversión Nacional de Colombia

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Análisis microeconómico de las características del cambio tecnológico y del proceso de innovaciones: el caso de Furfural y Derivados, SA México

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Características del mercado de crédito territorial y determinantes de la demanda: el caso colombiano

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Redistribuição espacial da população: características e tendências do caso brasileiro

Documento Docente - Programa Global de Formación en Población y Desarrollo

Análise Genética de Características Reprodutivas Na Raça Brahman

Aiming to establish selection criteria for the Brahman cattle in Brazil, the objective of this paper was to estimate genetic and environmental parameters for birth weight (BW), gestation length (GL) and scrotal circumference at 365 (SC365), 455 (SC455) and 550 (SC 550) days of age, and relative efficiency of indirect versus direct selection for these traits. Data were obtained from 15 851 animals belonging to 16 herds in six states, enrolled in a genetic breeding program. (Co)variance and heritability coefficients and genetic and environmental correlations between traits were estimated by restricted maximum likelihood (REML) under a multi trait animal model. The model included as fixed effects the contemporary group and the age of cow at calving as a covariate (linear and quadratic), and as random the direct genetic, the permanent environmental and residual effects. For BW and GL it was also considered the maternal genetic effect as random. Estimates of direct heritabilities were 0.36, 0.29, 0.55, 0.43 and 0.40 for BW, GL, SC365, SC455 and SC550, respectively. Genetic correlations between BW and GL, GL and SC365, GL and SC455, GL and SC550, SC365 and SC455, SC365 and SC550 and SC455 and SC550, were respectively 0.06, 0.13, 0.20, 0.13, 0.96, 0.98 and 0.99. The heritabilities estimates for all traits indicated these show enough additive genetic variability to respond favorably to selection. For sexual precocity, the best option would be SC365, due to the high value of heritability and to indirect selection at this age being more efficient than direct selection for PE455.