Abstract The dairy activity, based on pastures, represents the main source of income for the rural population of the Andes of northern Peru. The objective was to evaluate biomass yield, growth rate, plant height, Crude Protein (CP), Neutral Detergent Fiber (NDF), in vitro digestibility of dry matter (IVDDM) and metabolizable energy (ME) of 22 genotypes of Lolium spp. in three Andean floors (AF) (AF I: 2300 - 2800, AF II: 2801 - 3300 and AF III: 3301 - 3800 masl) in northern Peru. Better biomass (7662 kg dry material (DM) ha-1 year-1) and growth rate (21.0 kg DM ha-1 day-1) showed AF I for Lolium perenne L., however AF III stood out in yield (9,041 kg MS ha-1 year-1) and growth rate (24.8 kg DM ha-1 day-1) for Lolium multiflorum L. The mean ME was 2.61 Mcal kg-1 MS and 2.43 Mcal kg-1 MS for L. perenne and L. multiflorum, respectively. The nutritional values of both varieties are adequate for feeding cattle to grazing in the mountains. Likewise, the genotypes that showed better performance should be used in a pasture improvement plan.

Resumen La actividad lechera, basada en pasturas, representa la principal fuente de ingreso de la población rural de los andes del norte del Perú. El objetivo fue evaluar el rendimiento de biomasa, tasa de crecimiento, altura de planta, Proteína Cruda (PC), Fibra Detergente Neutro (FDN), digestibilidad in vitro de la materia seca (DIVMS) y Energía metabolizable (EM) de 22 genotipos de Lolium spp. en tres pisos altoandinos (PA) (PA I: 2300 - 2800, PA II: 2801 - 3300 y PA III: 3301 - 3800 msnm) del norte del Perú. Mejor biomasa (7 662 kg materia seca (MS) ha-1 año-1) y tasa de crecimiento (21,0 kg MS ha-1 día-1) mostró el PA I para Lolium perenne L., en cambio el PA III destacó en rendimiento (9041 kg MS ha-1 año-1) y tasa de crecimiento (24,8 kg MS ha-1 día-1) para Lolium multiflorum L. La EM promedio fue de 2,61 Mcal kg-1 MS y 2,43 Mcal kg-1 MS para L. perenne y L. multiflorum respectivamente. Los valores nutricionales de ambas variedades son adecuados para la alimentación del ganado al pastoreo en la sierra. Así mismo, los genotipos que mostraron mejor desempeño deben usarse en un plan de mejora de pasturas.

Introducción. La obesidad resulta de la interacción entre factores de riesgo genéticos y ambientales. Objetivo. Evaluar el efecto de tres variantes genéticas y factores ambientales en el exceso de peso en jóvenes de 10 a 18 años de Medellín, Colombia. Materiales y métodos. Se hizo un estudio transversal en 424 jóvenes divididos en tres grupos: 100 obesos, 112 jóvenes con sobrepeso, y, pareados con ellos, 212 jóvenes con peso adecuado, que conformaron el grupo de control. Se evaluó la asociación entre tres polimorfismos genéticos ( UCP3 -rs1800849, FTO -rs17817449 y CAPN10 -rs3842570) y el exceso de peso, así como su interacción con antecedentes familiares de enfermedad, el tiempo dedicado a ver televisión y a jugar videojuegos y el consumo de alimentos. Resultados. Los antecedentes familiares de obesidad, la dedicación de más de dos horas al día a ver televisión y jugar videojuegos, la falta de lactancia materna, el bajo consumo de cereales, legumbres, frutas y verduras y el gran consumo de comidas rápidas fueron más frecuentes entre los obesos que en los controles. Se observó una asociación significativa entre el genotipo I/I (SNP19 del CAPN10 ) y el exceso de peso, incluso en los jóvenes que llevaban una vida activa. Además, se encontró una asociación significativa entre los genotipos C/C del UCP3 y G/G y T/T del FTO y el exceso de peso, pero solo en los jóvenes sedentarios. Conclusiones. En esta población, la alimentación inadecuada y el sedentarismo aumentaron el riesgo de exceso de peso. El genotipo I/I de SNP19 del CAPN10 se asoció significativamente con el exceso de peso. Algunas variantes del FTO y el UCP3 mostraron tener efecto solo en jóvenes sedentarios.

Introduction : Obesity results from interaction between genetic and environmental risk factors. Objective: To evaluate the effect of three gene variants and environmental factors on obesity and overweight in young people aged 10 to 18 years in a Colombian population. Materials and methods: A total of 424 subjects were selected and separated into three groups for a cross-sectional study; 100 obese and 112 overweight subjects were matched with 212 normal-weight controls. Associations were evaluated between excess weight and three genetic polymorphisms ( UCP3- rs1800849, FTO -rs17817449, and CAPN10 -rs3842570), as well as the family history, the time spent watching television and playing video games, and the diet. Results: A family history of obesity, the time spent watching television and playing video games, the lack of breastfeeding, a low consumption of cereals, legumes, fruits, vegetables, and a high consumption of fast foods were characteristics typically found in obese individuals compared to controls. A significant association between genotype I/I (SNP19 of CAPN10 ) and excess weight was found even with an active lifestyle. In addition, significant associations between the C/C genotype of the UCP3 gene and the G/G and T/T genotypes of the FTO gene and excess weight were found only in young sedentary individuals. Conclusions: In this population, inadequate diet and sedentary lifestyle increased the risk of excess weight. Genotype I/I of SNP19 in CAPN10 was significantly associated with excess weight. In contrast, FTO and UCP3 variants exhibited effects only in sedentary environments.

A colonização potencial por plantas enraizadas (CPPE) e as áreas potenciais de colonização por plantas fluentes livres foram calculadas durante a fase de enchimento do reservatório de Yaciretá. Para obter o CPPE, a máxima profundidade de enraizamento observada previa o fechamento do rio e as curvas ipsográficas foram utilizadas. As espécies presentas na área pré-represamento foram classificadas de acordo com as diferentes bioformas antes da inclusão na análise: A extenção de CPPE (para profundidades entre 0-4 m) poderia alcançar 275 km² a 76 m acima do nível do mar (nível de água atual), enquanto na cota de 82 m acima do nível do mar (nível de recheio final) a zona litorânea será aumentada em aproximadamente 21,5%. A área potencial para macróficas emersas foi calculada em 99 km², para as plantas enraizadas com folhas flutuantes em 131 km², e para as plantas enraizadas submersas em 120 km², a 76 m acima do nível do mar. A 82 m acima do nível do mar, as macrófitas emersas poderiam alcançar 271 km². A informação de freqüência, velocidade de ventos, e de fetch, junto com dados de profundidade foram usados para delimitar áreas rasas e abrigadas, nas quais plantas flutuantes livres poderiam encontrar condições favoráveis para iniciar a colonização. As características físicas e químicas obtidas em oito estações de amostragem no início da formação do reservatório são discutidas em relação ao desenvolvimento potencial das macrófitas.

The potential colonization by anchored plants (PCAP) and the potential areas for initial colonization of free floating plants were estimated during the early filling phase for the Yaciretá reservoir. In order to obtain the PCAP, the observed maximum depth of colonization of the anchored macrophytes before impoundment and the hypsographic curves were used. The species inhabiting the pre-impoundment area were classified according to the different bioforms before the inclussion in the analysis. The areal extent of PCAP (from depths between 0-4 m) could reach 275 km² at 76 m above sea level (current water level), whereas at 82 m above sea level (final filling level) the littoral zone will be increased by about 21.5%. The potential area for geophytes was estimated to be 99 km²; 131 km² for root-floating leaved plants and 120 km² for submerged plants, at 76 m above sea level. At 82 m above sea level, the geophytes could reach 271 km². The data for wind frequency, velocity and fetch, together with depth were used to calculate shallow and sheltered areas in which free floating plants could find favourable conditions to initial colonization. Physical and chemical features recorded at eight stations during the early filling phase are discussed in relation to potential plant development.