Metaanálisis del uso de semillas y aceites en la dieta de ovejas y cabras

Abstract

Resumen -El objetivo de este trabajo fue utilizar el metaanálisis para estudiar los resultados productivos de ovejas y cabras de ordeño, alimentadas con aceites y semillas ricas en ácidos grasos insaturados. Se utilizaron 22 experimentos con ovejas (63 tratamientos) y 21 con cabras (76 tratamientos). El consumo medio de grasa extra fue de 83,6±33,6 g por día en ovejas y 73,4±38,7 g por día en cabras. En ovejas, la grasa extra no afectó al consumo de materia seca, pero aumentó la producción de grasa (de 91,4 a 98,8 g por día) y redujo el contenido proteico (de 5,41 a 5,24%) de la leche. No hubo diferencias en el extracto quesero. En cabras, la inclusión de grasa en la dieta redujo el consumo de materia seca (de 2,13 a 2,08 kg por día) y aumentó el porcentaje de grasa láctea (de 4,11 a 4,43%) y el extracto quesero (de 7,41 a 7,76%). La respuesta productiva de ovejas y cabras al consumo de dietas ricas en ácidos grasos insaturados es diferente. Sin embargo, el valor comercial de la leche no se ve afectado, debido a la ausencia de efectos negativos sobre el extracto quesero en ambas especies.Términos para indexación: ácidos grasos insaturados, grasa, leche, producción animal, proteína. Meta-analysis of the use of oilseeds and oils in ewe and goat dietsAbstract -The objective of this work was to use meta-analysis to study the productive results of ewe and goat fed oil and seed, rich in unsatured fat acid. Twenty-two experiments with ewes (63 treatments) and 21 experiments with goats (76 treatments) were used. Average extra fat intake was 83.6±33.6 g per day in ewes, and 73.4±38.7 g per day in goats. In ewes, extra fat intake did not affect dry matter intake, but increased milk fat yield (from 91.4 to 98.8 g per day) and reduced milk protein content (from 5.41 to 5.24%). There were no differences in the sum of fat and protein contents. In goats, extra fat included in the diet reduced dry matter intake (from 2.13 to 2.08 kg per day), and increased milk fat percentage (from 4.11 to 4.43%) and the sum of fat and protein contents (from 7.41 to 7.76%). The yield responses to the intake of diets enriched with unsaturated fatty acids differ between ewes and goats. However, milk commercial value is not affected because of the absence of negative effects on the sum of fat and protein contents in both species.

Chemical composition of corn silage produced by scientific studies in Brazil - A meta-analysis

“…According to Luiz (2002), a meta-analysis aims to extract additional information from existing data, by combining the data of several studies and applying one or more statistical techniques. Meta-analysis has been reported as a useful statistical method for objectively evaluating research data (SAUVANT et al, 2008;MARÍN et al, 2015), and the strategy also has the potential to facilitate discoveries based on published literature, since it can provide greater statistical power than individual studies, owing to the substantial increase in sample size (RABIEE et al, 2012). Accordingly, the objective of the present study was to perform a meta-analysis of corn silage produced by research groups in Brazil, in order to compare the chemical composition of silage from studies that focused on improving the production, management, and use of silage and that of silage from studies that only used silage as roughage.…”

Síntesis de calostro y desarrollo de las crías por efecto de la inclusión de aceite de soya en la dieta preparto de ovejas de pelo

“…Algunos estudios (21,23) señalan que la suplementación de aceites vegetales mejora la producción de leche en ovejas y cabras debido a que aumenta el nivel de energía en la dieta. También se ha reportado que la inclusión de aceites vegetales en dietas formuladas isoenergética e isoprotéicamente provoca que se incluya un mayor nivel de forraje (24,25) .…”