Genetic selection for ovulation rate and litter size in rabbits: estimation of genetic parameters and direct and correlated responses

The aim of this work was to estimate direct and correlated responses in survival rates in an experiment of selection for ovulation rate (OR) and litter size (LS) in a line of rabbits (OR_LS). From generation 0 to 6 (first selection period), females were selected only for second gestation OR estimated by laparoscopy. From generation 7 to 13 (second selection period), a 2-stage selection for OR and LS was performed. In stage 1, females having the greatest OR at second gestation were selected. In stage 2, selection was for the greatest average LS of the first 2 parities of the females selected in stage 1. Total selection pressure in females was about 30%. The line had approximately 17 males and 75 females per generation. Traits recorded were OR estimated as the number of corpora lutea in both ovaries, number of implanted embryos (IE) estimated as the number of implantation sites, LS estimated as total number of rabbits born recorded at each parity, embryo survival (ES) estimated as IE/OR, fetal survival (FS) estimated as LS/IE, and prenatal survival (PS) estimated as LS/OR. Data were analyzed using Bayesian methodology. The estimated heritabilities of LS, OR, IE, ES, FS, and PS were 0.07, 0.21, 0.10, 0.07, 0.12, and 0.16, respectively. Direct and correlated responses from this study were estimated in each period of selection as the difference between the average genetic values of last and first generation. In the first selection period, OR increased 1.36 ova, but no correlated response was observed in LS due to a decrease on FS. Correlated responses for IE, ES, FS, and PS in the first selection period were 1.11, 0.00, -0.04, and -0.01, respectively. After 7 generations of 2-stage selection for OR and LS, OR increased 1.0 ova and response in LS was 0.9 kits. Correlated responses for IE, ES, FS, and PS in the second selection period were 1.14, 0.02, 0.02, and 0.07, respectively. Two-stage selection for OR and LS can be a promising procedure to improve LS in rabbits.This study was supported by the Comision Interministerial de Ciencia y Tecnologia CICYT-AGL2005-07624-C03-01 CICYT-AGL2008-05514-C02-01 and by funds from Generalitat Valenciana research programme (Prometeo 2009/125).Ziadi, C.; Mocé Cervera, ML.; Laborda Vidal, P.; Blasco Mateu, A.; Santacreu Jerez, MA. (2013). Genetic selection for ovulation rate and litter size in rabbits: estimation of genetic parameters and direct and correlated responses. Journal of Animal Science. 91(7):3113-3120. https://doi.org/10.2527/jas.2012-6043S3113312091

Desarrollo de un cuestionario para la valoración y cuantificación de los hábitos de vida relacionados con el sobrepeso y la obesidad Development of a questionnaire for the assessment and quantification of overweight and obesity related lifestyles

Introducción: La modificación de la conducta es imprescindible en el tratamiento de la obesidad. El objetivo de este estudio es diseñar un cuestionario que permita describir y cuantificar las conductas relacionadas con la obesidad en la población obesa española. Material y métodos: Un grupo de expertos diseñó un cuestionario inicial de 57 preguntas tipo Likert que se administró a 335 pacientes con sobrepeso (110 hombres y 225 mujeres; edad, 42 ± 14 años; IMC, 32,6 ± 3,7 kg/m²). Tras una primera fase de búsqueda de la dimensionalidad subyacente y de reducción de preguntas, se administró un cuestionario depurado de 24 preguntas a una muestra de 156 pacientes con sobrepeso (52 hombres y 104 mujeres; edad 42 ± 12 años; IMC, 33,1 ± 3,5 kg/m²), repitiéndose en 56 de ellos para obtener información test-retest. Resultados: El cuestionario final incluye 22 preguntas agrupadas en cinco dimensiones: contenido calórico de la dieta, comer por bienestar psicológico, ejercicio físico, alimentación saludable y consumo de alcohol. La estructura factorial encontrada se reproduce en lo esencial utilizando muestras distintas y diferentes métodos de extracción: en todas las dimensiones se obtienen índices de fiabilidad alfa por encima de 0,75, excepto en consumo de alcohol; la estabilidad test-retest es superior a 0,90 en todas las dimensiones excepto en consumo de alcohol; en los análisis de validez efectuados (de constructo, de contenido y discriminativa) los resultados son muy satisfactorios. Conclusiones: Los resultados del estudio métrico (fiabilidad y validez) ponen de manifiesto que el cuestionario propuesto es una excelente herramienta para valorar los hábitos de vida relacionados con el control de la obesidad.Introduction: Lifestyle intervention is mandatory for obesity treatment. The aim of this study is to design a questionnaire to describe and quantify those behaviours more closely related to obesity in the Spanish obese population. Methods and procedures: An expert panel designed a preliminary 57 Liker-type item questionnaire, which was self-administered to 335 overweight patients (110 male, 225 female; age, 42 ± 14 years; BMI, 32,6 ± 3,7 kg/m²). After a subjacent dimensionality searching and item reducing first phase, a shrunk questionnaire of 24 items was then self-administered to 156 overweight patients (52 male, 104 female; age 42 ± 12 years; BMI, 33,1 ± 3,5 kg/m²); 56 of those patients were re-administered the questionnaire in order to provide test-retest information. Results: Final questionnaire includes 22 items clustered in five dimensions: diet caloric intake, searching for psychological well-being eating, physical activity, healthy eating and alcohol intake. Proposed factorial structure is mostly reproduced in different samples and using different extraction methods: all dimensions but alcohol intake score alpha values > 0,75 for liability; test-retest stability is greater than 0,90 in all dimensions but alcohol intake; results for all validity tests performed (of construct, of content and discriminative) are highly satisfactory. Conclusion: Metrics study results (liability and validity) demonstrate that the proposed questionnaire provides an excellent tool to assess those lifestyles related to obesity control

Desarrollo de un cuestionario para la valoración y cuantificación de los hábitos de vida relacionados con el sobrepeso y la obesidad

Introducción: La modificación de la conducta es imprescindible en el tratamiento de la obesidad. El objetivo de este estudio es diseñar un cuestionario que permita describir y cuantificar las conductas relacionadas con la obesidad en la población obesa española. Material y métodos: Un grupo de expertos diseñó un cuestionario inicial de 57 preguntas tipo Likert que se administró a 335 pacientes con sobrepeso (110 hombres y 225 mujeres; edad, 42 ± 14 años; IMC, 32,6 ± 3,7 kg/m 2 ). Tras una primera fase de búsqueda de la dimensionalidad subyacente y de reducción de preguntas, se administró un cuestionario depurado de 24 preguntas a una muestra de 156 pacientes con sobrepeso (52 hombres y 104 mujeres; edad 42 ± 12 años; IMC, 33,1 ± 3,5 kg/m 2 ), repitiéndose en 56 de ellos para obtener información test-retest. Resultados: El cuestionario final incluye 22 preguntas agrupadas en cinco dimensiones: contenido calórico de la dieta, comer por bienestar psicológico, ejercicio físico, alimentación saludable y consumo de alcohol. La estructura factorial encontrada se reproduce en lo esencial utilizando muestras distintas y diferentes métodos de extracción: en todas las dimensiones se obtienen índices de fiabilidad alfa por encima de 0,75, excepto en consumo de alcohol; la estabilidad test-retest es superior a 0,90 en todas las dimensiones excepto en consumo de alcohol; en los análisis de validez efectuados (de constructo, de contenido y discriminativa) los resultados son muy satisfactorios. Conclusiones: Los resultados del estudio métrico (fiabilidad y validez) ponen de manifiesto que el cuestionario propuesto es una excelente herramienta para valorar los hábitos de vida relacionados con el control de la obesidad

Spin adapted versus broken symmetry approaches in the description of magnetic coupling in heterodinuclear complexes

The performance of a series of wave function and density functional theory based methods in predicting the magnetic coupling constant of a family of heterodinuclear magnetic complexes has been studied. For the former, the accuracy is similar to other simple cases involving homodinuclear complexes, the main limitation being a sufficient inclusion of dynamical correlation effects. Nevertheless, these series of calculations provide an appropriate benchmark for density functional theory based methods. Here, the usual broken symmetry approach provides a convenient framework to predict the magnetic coupling constants but requires deriving the appropriate mapping. At variance with simple dinuclear complexes, spin projection based techniques cannot recover the corresponding (approximate) spin adapted solution. Present results also show that current implementation of spin flip techniques leads to unphysical results.close2