RESUMEN La sobre mortalidad invernal se explica principalmente por las enfermedades respiratorias y circulatorias. Los pronósticos biometeorológicos son pronósticos especializados del estado del tiempo, dirigidos, precisamente, a identificar y avisar con antelación suficiente la ocurrencia de los llamados efectos meteoro-trópicos. El objetivo de la investigación estuvo dirigido a evaluar la efectividad de un pronóstico biometeorológicos en la prevención de enfermedades para una mejor adaptación al cambio climático. Se realizó un estudio pre-experimental prospectivo entre el 1 de noviembre de 2020 al 30 de abril de 2021, se trabajó en seis consultorios médico de familia en el área “Idalberto Revuelta” de Sagua la Grande, Villa Clara, Cuba, con una población de 4 806 pacientes. Se hizo hincapié en las enfermedades cardiovasculares y cerebrovascular, así como las infecciones respiratorias. Durante la temporada invernal 2020-2021, se emitieron 6 alertas tempranas. Las enfermedades evaluadas en este estudio se encontraron reducción marcada de la incidencia en la comunidad, en el caso de las infecciones respiratorias, la incidencia del Infarto agudo de Miocardio y las enfermedades Cerebrovascular. Se aplicó el sistema de alerta temprana, a los pacientes vulnerables pertenecientes a esos seis policlínicos, demostrando su efectividad con la reducción de la morbi-mortalidad de las entidades analizadas.

ABSTRACT Winter excess mortality is mainly explained by respiratory and circulatory diseases. Biometeorological forecasts are specialized weather forecasts aimed, precisely, at identifying and warning in advance the occurrence of the so-called meteorological-tropic effects. The objective of the research was aimed at evaluating the effectiveness of a biometeorological forecast in the prevention of diseases for a better adaptation to climate change. A prospective pre-experimental study was carried out from November 1, 2020 to April 30, 2021, in six family doctor's offices in the "Idalberto Revuelta" area of Sagua la Grande, Villa Clara, Cuba, with a population of 4,806 patients. Emphasis was placed on cardiovascular and cerebrovascular diseases, as well as respiratory infections. During the 2020-2021 winter season, 6 early warnings were issued. The diseases evaluated in this study were found to have a marked reduction in the incidence in the community, in the case of respiratory infections, the incidence of acute myocardial infarction and cerebrovascular diseases. The early warning system was applied to vulnerable patients belonging to these six polyclinics, demonstrating its effectiveness in reducing morbidity and mortality of the entities analyzed.

RESUMEN En condiciones del trópico colombiano es necesario establecer estrategias de alimentación que permitan aumentar la productividad a bajo costo. El objetivo de esta investigación fue evaluar el efecto de la suplementación con ensilados de totumo, mango, guayabo de monte sobre la digestibilidad in vitro, degradabilidad y parámetros productivos en vacas doble propósito. El estudio fue realizado en la finca La Florida, ubicada, en el municipio de Puerto Boyacá, se usaron 32 vacas (Gyr x Holstein) con peso promedio de 460 ±35 kg en primer tercio de lactación, distribuidas en cuatro (4) grupos de ocho (8) cada uno, conformados de la siguiente manera: T1: grupo control: sin ensilajes; T2: ensilaje de Guayabo de monte; T3: ensilaje de Totumo y T4: ensilaje de Mango común. Todas las vacas permanecieron en pastoreo rotacional con Brachiaria decumbens, agua a voluntad y sal mineralizada. Se analizó el efecto del tratamiento, el tiempo y su interacción, para ello se usó el comando PROC MIXED del software SAS 9.2 (2002), la diferencias entre promedios se realizó mediante prueba de Tukey-Kramer, con nivel de significancia del 5 %. No hubo diferencias (p<0,05) en la producción diaria de leche entre los tratamientos evaluados, sin embargo, el porcentaje de proteína en leche fue mayor (p<0,05) en los tratamientos T2 y T4. EL NUL fue mayor en el T2 y menor en el T4. El consumo de ensilajes fue mayor (p<0,05) en el T4 y la condición corporal mostró ser mejor para los tratamientos T2 y T4, finalmente para los parámetros de degradabilidad y digestibilidad in vitro, los tratamientos T2, T3 y T4 obtuvieron los mayores valores respectivamente. La suplementación de vacas doble propósito con ensilajes de frutos del bosque húmedo tropical mejora la proteína de la leche y la condición corporal de las vacas. Los ensilados estudiados, poseen alta tasa de degradación y digestibilidad In vitro, representando una alternativa de alimentación en los rumiantes.

ABSTRACT In the Colombian tropic, it is necessary to establish feeding strategies that increase productivity and reduce costs. This research aimed to evaluate the effect of totumo, mango, and wild guava silage on in vitro digestibility, degradability, and productive parameters in dual-purpose cows. This study was carried out on a farm located in the municipality of Puerto Boyacá. Thirty-two Gyr x Holstein cows (Body weight = 460 ± 35 kg) in early lactation were enrolled and distributed in four groups of eight individuals: T1: control group: no silage; T2: Wild guava silage; T3: Totumo silage and T4: Mango silage. All the cows remained in a rotational grazing system with Brachiaria decumbens, water, and a salt-based mineral supplement ad libitum. There were no differences (p>0,05) in the daily milk production. However, protein levels in milk were higher (p<0,05) in the T2 and T4 treatments. NUL was more elevated in T2 and lower in T4. Silage consumption was higher (p<0,05) in T4, and the body condition score was higher for T2 and T4. For the degradability and digestibility parameters in vitro, treatments T2, T3, and T4 obtained the highest values. Fruits silage supplementation on dual-purpose cows with silage fruits can increase milk protein levels and body condition score. Those silages have a high rate of degradation and in vitro digestibility, representing a feeding alternative for ruminants.

Resumen En sus ejercicios pictóricos, David Orbea ha destacado por simplificar formas que encuentra en diversos medios, desde fotografías de prensa hasta productos comerciales. Algunas de sus series adquieren cualidades abstractas, conservando su capacidad para comentar la realidad circundante. Por ejemplo, en 2015 intervino cajas de productos de consumo masivo, logrando una estetización que trascendía la categoría de los objetos utilizados como soporte. Hacia 2017, se aplicó a libros sobre liderazgo, lo que permitía proyectar asociaciones sociales o políticas. En “Trópico Informal”, Orbea se enfoca en los esquemas cromáticos de construcciones urbanas, creando un mundo pictórico peculiar. Además, explora elementos arquitectónicos modernos y crea esculturas en cemento. Su enfoque en la informalidad tropical y la abstracción se traduce en una "abstracción sucia", que captura la identidad de sus referentes originales. De esta manera, preserva lo popular de manera sofisticada, capturando el simbolismo que atraviesa la estridencia de la vida urbana.

Abstract In his pictorial exercises, David Orbea is known for simplifying forms found in various media, from press photographs to commercial products. Some of his series take on abstract qualities while retaining their ability to comment on the surrounding reality. For instance, in 2015, he intervened with boxes of mass consumer products, achieving an aestheticization that transcended the category of the objects used as support. By 2017, he focused on leadership books, allowing for social or political associations. In “Trópico Informal,” Orbea focuses on the chromatic schemes of urban constructions, creating a unique pictorial world. Additionally, he explores modern architectural elements and creates cement sculptures. His focus on tropical informality and abstraction results in a "dirty abstraction" that captures the identity of his original references. In this way, he preserves the popular in a sophisticated manner, elegantly capturing the symbolic essence that permeates the urban clamor.

Resumen Introducción. El maíz amarillo duro (Zea mays L.) es fuente principal para elaborar alimentos, por lo que se requiere generar híbridos con rendimientos superiores a 2,8 t ha-1 y adaptabilidad climática. Objetivo. Evaluar y comparar el comportamiento agronómico de cinco híbridos trilineales experimentales de maíz amarillo duro y la variedad Marginal 28T, en ocho localidades del trópico peruano. Materiales y métodos. El experimento se realizó en dos fases: de marzo del 2018 a marzo del 2019 en cuatro parcelas de validación en San Martín y de marzo a diciembre del 2019 en cuatro parcelas de adaptabilidad en San Martín, Pucallpa, Loreto y Amazonas. Las variables evaluadas fueron: altura de planta y mazorca, dimensiones y peso de mazorca, acame de raíz, resistencia a roya y rendimiento (t ha-1). Se aplicó el diseño de bloques completos al azar con análisis combinado y la interacción genotipo x ambiente del rendimiento con el modelo efectos aditivos principales y modelos de interacción multiplicativa. Resultados. El híbrido HTE6 fue superior en diámetro de mazorca (4,66 cm), peso de mazorca (190,76 g), número de hileras por mazorca (14,26), granos por hilera (37,45), peso total de grano (156,21 g) y rendimiento de grano (7,21 t ha-1). HTE6 mostró adaptabilidad superior en Iquitos (9,20 t ha-1) y San Martín (8,10 t ha-1). En la interacción genotipo-ambiente alcanzó 7,18 t ha-1 y fue el más estable en las ocho localidades. Conclusión. De los cinco híbridos evaluados y la variedad Marginal 28T, el HTE6 tuvo el mejor desempeño agronómico y el mayor rendimiento en las ocho localidades evaluadas. Por lo que se consideró el híbrido trilineal para su liberación comercial en regiones del trópico peruano.

Abstract Introduction. Hard yellow corn (Zea mays L.) is the main source for food processing; therefore, it is necessary to generate hybrids with yields higher than 2.8 t ha-1 and climatic adaptability. Objective. To evaluate and compare the agronomic behavior of five experimental trilinear hybrids of hard yellow corn maize and the Marginal 28T variety in eight tropical Peruvian locations. Materials and methods. The experiment took place in two phases: from March 2018 to March 2019 in four validation plots in San Martin, and from March to December 2019 in four adaptabilities plots in San Martín, Pucallpa, Loreto, and Amazonas. The evaluated variables were: plant and ear height, size and weight of ear, roots lodging, rust resistance, and yield (t ha-1). A randomized complete block design was applied, with a combined analysis of yield genotype x environment interaction with the additive main effects and multiplicative interaction models. Results. The hybrid HTE6 had the highest ear diameter (4.66 cm), ear weight (190, 76 g), number of rows per ear (14.26), grains per row (37.45), total grain weight (156.21 g), and grain yield (7.21 t ha-1). HTE6 showed superior adaptability in Iquitos (9.2 t ha-1) and San Martín (8.1 t ha-1). In the genotype-environmental interaction, it reached 7.18 t ha-1, with the highest stability in the eight localities. Conclusion. Among the five trilinear hybrids and the Marginal 28T variety, the HTE6 had the best agronomic performance and the highest yield in the eight evaluated locations. Thus, it is considered the more suitable trilinear hybrid for the tropical conditions of Peru.

Resumen: El objetivo fue analizar la rentabilidad del proyecto de instalación de techos verdes extensivos en viviendas ubicadas en un clima tropical húmedo, considerando el efecto de diversos parámetros sobre la relación beneficio costo y el periodo de recuperación de la inversión. Los beneficios ambientales se estimaron a partir del análisis de ciclo de vida, mientras que el análisis de costos unitarios permitió determinar el efecto de la disponibilidad de materiales sobre los costos de instalación. El análisis monetizó dos beneficios ambientales: el ahorro de energía eléctrica y la captura de carbono, a partir del valor presente neto de los costos de instalación, mantenimiento, desmantelamiento y disposición final. Se determinó que la relación beneficio-costo varía entre 1.1 y 3.8 con periodos de recuperación de 3.4 a 8.9 años, en función de la disponibilidad de materiales, los indicadores económicos, las acciones de mantenimiento y la recompensa potencial con bonos de carbono al propietario.

Abstract: The objective was to analyze the profitability of the project for the installation of extensive green roofs on houses located in a humid tropical climate, considering the effect of various parameters on the benefit-cost ratio and the payback period of the investment. The environmental benefits were estimated from the life cycle analysis, while the unit cost analysis allowed determining the effect of material availability on installation costs. The analysis monetized two environmental benefits: electricity savings and carbon sequestration, based on the net present value of installation, maintenance, dismantling and disposal costs. The benefit-cost ratio was found to range from 1.1 to 3.8 with payback periods of 3.4 to 8.9 years, depending on the availability of materials, economic indicators, maintenance actions and the potential reward with carbon credits to the owner.

Resumen El toro es un factor de importancia genética y económica en un hato ganadero, ya que de este dependerán las próximas generaciones; por lo tanto, es esencial la evaluación de la calidad seminal y la criopreservación de su material genético. El objetivo del estudio fue evaluar el efecto de dos temperaturas de dilución sobre la calidad de semen de ganado cebuino del Trópico Peruano. Dos toros Gyr fueron colectados semanalmente mediante electroeyaculación. Las muestras se colocaron en baño maría a 34°C y se analizaron las características macroscópicas y microscópicas del semen. Solo los eyaculados con >60% de motilidad y <20% de anormalidades fueron procesados, separándolos en dos tratamientos. El T1 consistió en predilución 1:1 a 34°C, luego de 30 minutos una dilución final agregando el dilutor a 34°C. El T2 consistió en predilución 1:1 a 34°C y a los 30 minutos de estabilización se llevó a refrigeración conjuntamente con el dilutor, para luego realizar la dilución final a 5°C. La calidad seminal fue analizada luego de 16 horas de refrigeración. El porcentaje de vitalidad en T1 (80,89%) fue mayor que en T2 (71,22%) (p<0,05), la reacción positiva a la prueba hipoosmótica fue mayor en T1 (71,11%) que en T2 (60%) (p<0,05). La integridad acrosomal y los rasgos morfométricos no variaron según tratamientos. En conclusión, la dilución inicial y final a 34°C en toros Gyr influye positivamente sobre la calidad seminal antes de la congelación de pajillas de semen.

Abstract The bull is a factor of genetic and economic importance in cattle breed, since the next generations will depend on it; therefore, the evaluation of the seminal quality and the cryopreservation of its genetic material are essential. The aim of the study was to evaluate the effect of two dilution temperatures on the quality of semen from zebuine cattle from the Peruvian Tropics. The samples were placed in a water bath at 34°C and the macroscopic and microscopic characteristics of semen were analyzed. Only the ejaculates with >60% motility and <20% abnormalities were processed, separating them into two treatments. T1 consisted of a 1:1 predilution at 34°C, followed by a final dilution of 30 minutes by adding the dilutor at 34°C. T2 consisted of a 1:1 predilution at 34°C and after 30 minutes of stabilization, refrigeration was carried out together with the dilutor, in order to carry out the final dilution at 5°C. The seminal quality was analyzed after 16 hours of refrigeration. The percentage of vitality in T1 (80.89%) was greater than in T2 (71.22%) (p<0.05), the positive reaction to the hypoosmotic problem was greater in T1 (71.11%) than in T2 (60%) (p<0.05). Acrosomal integrity and morphometric features did not vary according to treatments. In conclusion, the initial and final dilution at 34°C in Gyr bulls positively influences the semen quality before the freezing of semen packets.

Abstract Plastic pollution represents a threat to marine ecosystems and has therefore been gaining space in the realm of public interest. In this study, we investigated the ingestion of food and non-food items (i.e., plastic particles) by fish and crabs. These animals are commonly collected by trawling with a double-ring net along the coast of Cananéia, state of São Paulo, Brazil; some of them are consumed as food by the local population. Fish and crab stomachs were removed and dissected, and their contents were examined under a stereoscopic microscope with an image-capturing system. The presence or absence of plastic was also registered. We examined 139 specimens of 16 fish species and 143 specimens of four crab species. The most frequent food items found in fish were unidentified food, followed by crustaceans, molluscs, polychaetes, and other fish; in crabs, the items were unidentified food, followed by crustaceans, molluscs and fish. Plastic particles were found in all fish species, representing 47.5% of the individuals analysed. In crabs, the incidence of plastic was lower, occurring in only two species (5% in Callinectes danae and 3% in C. ornatus). Only four fish species analysed had previous records of plastic ingestion in the scientific literature. The high incidence of microplastics in our study is worrying because they negatively affect the animals’ lives and can be transferred through the tropic web to top predators, including humans, through the ingestion of contaminated animals.

Abstract Brazil is located between the Equator and Tropic of Capricorn, which allows diverse climates, reliefs, and habitats for arthropods, which sting represents a risk to human health and a public health issue. This manuscript updates the epidemiological data of cases of human envenoming by spiders, scorpions, and insects with medical relevance in Brazil from 2010 to 2021. Epidemiological data were taken using the Brazilian Notifiable Diseases Information System. Statistics of non-parametric data used the Kruskal-Wallis followed by the Nemenyi test. On average, more than 145,000 envenomation and 145 deaths are recorded annually, and more than 60% of deaths are caused by scorpion bites. When the number of deaths was pondered by the number of cases with each arthropod, bees kill the most. Most stings cause mild symptoms and affect men of working age. The incidence decreases during the colder months, which is better noticeable in regions with well-defined seasons. The distribution is distinct among the regions: Southeast, Northeast, and South have the highest rate of bites. The growing number of cases of envenomation reported annually is a serious public health concern, especially involving scorpions, and highlights the importance of studying arthropod venom and improving the therapies.

ABSTRACT In order to estimate the adaptability of Agricultural Production Systems Simulator (APSIM)-Maize model under the special climate environment in tropic, 10 field experiments were conducted at different seasons in three sites (Longchuan, Mangshi and Ruili) of tropic in Yunnan Province, China. The parameters of APSIM model were calibrated and its adaptability was validated. The results showed that the days from sowing to flowering and sowing to maturity were predicted accurately for all sites with mean errors of 2.0 ± 0.4, and 3.2 ± 0.7 d respectively. The normalized root mean square errors (NRMSE) of the model for yield prediction were 2%, 3% and 5% for each of three sites, respectively, which indicated that the APSIM model had good accuracy and sensitivity in predicting phenological phases and yield of maize (Zea mays L.) grown in different seasons, and the model had good adaptability in the tropic of Southwest China. This study provided the basis and technical support for evaluating maize production potential based on the model.

Resumo O presente trabalho teve por objetivo identificar a razão entre área de janela e piso, associada à iluminação natural eficaz e à eficiência energética, no trópico úmido. As recomendações de pré-dimensionamento mais usadas por arquitetos nas etapas preliminares de projeto, visando a uma iluminação natural eficaz, abordam o tamanho da janela e a profundidade do ambiente. Códigos de obras brasileiros determinam relações entre área de janela e piso para garantir iluminação natural adequada, mas essas relações não estão respaldadas em trabalhos científicos. O método consistiu em uma análise comparativa do desempenho de modelos quanto à iluminância natural útil, à uniformidade da iluminação natural, à iluminância natural excessiva e ao consumo energético com iluminação e resfriamento a fim de comparar relações janela/piso emcondições de janela sombreada, ar-condicionado e iluminação híbrida. As iluminâncias e o consumo energético foram simulados com as ferramentas Daysim e DesignBuilder. A análise dos dados comparou a amplitude de variação do desempenho de grupos de modelos, classificados por quatro valores da razão janela/piso. Os resultados validaram a eficácia da razão 1/6, mas não da razão 1/8, ambas exigidas por códigos de edificações brasileiros. Também demonstraram a eficácia das razões 2/6 e 2/8, que não constam nos códigos de cidades com clima quente e úmido.

Abstract This study aimed to identify the window to floor ratio associated with effective daylighting and energy efficiency in the humid tropics. The rule of thumb most used by architects in preliminary design stages, aiming at adequate natural lighting, addresses window area and room depth. Brazilian building codes determine window to floor ratio values to ensure better natural lighting conditions, but those ratios are not based on scientific works. The method of this study consisted of a comparative analysis of the performance of models regarding useful daylight, daylight uniformity, daylight glare, and energy consumption with lighting and cooling,in order to compare the window to floor ratios under a shaded window, air conditioning, and hybrid lighting. The Daysim and DesignBuilder tools simulated illuminances and energy consumption. Data analysis compared the range of variation in the performance of groups of models, classified by four window-to-floor ratios. The results validated the effectiveness of the 1/6 ratio, but not the 1/8 ratio, both required by Brazilian building codes. The results showed the effectiveness of the 2/6 and 2/8 ratios, which are not included in the codes of cities with hot and humid climates.

Resumen Rajchenberg, M. 2022. Una aproximación a la biogeografía de los hongos políporos (Agaricomycotina, Basidiomycota) del sur de Sudamérica. Darwiniana, nueva serie 10(2): 451-479. Se analizaron los hongos políporoides de los bosques de la Patagonia de Argentina y Chile desde un punto de vista biogeográfico, a través de la óptica de estudios filogenéticos. Se aceptaron 72 especies, incluidas 4 taxones que aún no están descriptos formalmente. Las especies fueron distribuidas ya sea como cosmopolitas (14 spp.), antitropicales (7 spp.), pantropicales + austral-antárticas (3 spp.), neotropicales (4 spp.), sur-temperadas (= endémicas, 28 spp.), austral-antárticas (14 spp.) o circun- australes (2 spp.). Fueron registradas en las provincias Valdiviana (71 spp.), Magellánica (22 spp.) y del Maule (21 spp.). Tres de estas especies también estuvieron distribuidas hacia el norte en Chile y otras 8 también fueron encontradas en la provincia Juan Fernández. Casi el 35% de las especies son taxones productores de pudrición marrón en el leño, representando un porcentaje relativamente alto en la funga de políporos de la Patagonia cuando se la compara con otras regiones del mundo; la mayoría de estas especies están asociadas a Nothofagaceae y no a coníferas, como ocurre en el hemisferio norte. Nothophellinus demostró ser el único género endémico, Neophellinus mostró ser un género de distribución sub-amazónico, y Arambarria un género austral con representantes en el sur de Sudamérica (al sur del Trópico de Capricornio) y en la región florística del Cabo. Para cada especie se presenta un reporte de su ubicación filogenética sobre bases bibliográficas, con análisis de su distribución geográfica y sus relaciones con otras especies del género donde se la acepta. Los linajes australes se destacan a nivel de género (Gloeoporellus, Macrohyporia, Neolentiporus, Ryvardenia; que incluyen 5 especies) y a nivel de especie (que incluyen otros 12 taxones). Se señalan los casos de especiación en proceso y los completados. Se proponen las siguientes nuevas combinaciones: Cyanosporus venatus, Neophellinus livescens y Postia exigua.

Abstract Rajchenberg, M. 2022. An approach to the biogeography of polypore fungi (Agaricomycotina, Basidiomycota) in southern South America. Darwiniana, nueva serie 10(2): 451-479. The polyporoid fungi from the Patagonian Andes forests of Argentina and Chile were analyzed from a biogeographic point of view through the optics of phylogenetic studies. A total of 72 species are accepted, including 4 that are still unpublished. Species were distributed as either Cosmopolitan (14 spp.), Antitropical (7 spp.), Pantropical + Austral-antarctic (3 spp.), Neotropical (4 spp.), South- temperate (= endemic, 28 spp.), Austral-antarctic (14 spp.) or Circum-austral (2 spp.) in distribution. They were recorded in the Valdivian province (71 spp.), but also in the Magellanic province (22 spp.) and the Maule province (21 spp.). Three species were also distributed northward in Chile and other 8 species were also found in Juan Fernández province. Almost 35% of the species are brown wood- rotting taxa, representing a relatively high percentage in the polypore funga of Patagonia as compared with other world regions; they are mostly associated with Nothofagaceae, not conifers as in the North Hemisphere. Nothophellinus proved to be the single endemic genus, Neophellinus is shown to be a sub- Amazonian genus, and Arambarria an austral genus with representatives in southern South America (south of the Tropic of Capricorn) and the Cape floristic region. For each species, a detailed account of the phylogeny is presented according to the literature, along with insights into its geographical distribution and relationships with other taxa in the genus where it is accepted. Austral lineages are highlighted at genus level (Gloeoporellus, Macrohyporia, Neolentiporus, Ryvardenia; incl. 5 species) and species level (another 12 taxa). Ongoing and completed speciation processes are pointed out. The following new combinations are proposed: Cyanosporus venatus, Neophellinus livescens and Postia exigua.

Resumen El objetivo de este estudio fue analizar la estrategia que instrumentan 19 microempresas que elaboran quesos artesanales en el trópico de México. El análisis se llevó a cabo mediante el cálculo de un índice de estrategia a partir de la detección de las acciones implementadas en los ámbitos de colaboración, innovación, canales de comercialización, supervivencia financiera, diferenciación y relación con el consumidor, para comparar la combinación de estrategias con la que se enfrentan a un mercado cambiante. A partir de un análisis de conglomerados no jerárquico, cuya variable de agrupación fue el índice de estrategia por categoría, se diferenció el comportamiento de cada grupo de microempresas. Resultaron cuatro mecanismos a partir de la combinación de estrategias que cada grupo de microempresas lleva a cabo. Se concluyó que, para sobrevivir en el mercado, estas microempresas han desarrollado acciones estratégicas diferenciadas, entre las que predominan las de canal de venta, en tres de cuatro conglomerados, y las de colaboración, en dos de cuatro conglomerados. No se detectaron diferencias entre grupos respecto a las acciones relacionadas con la sobrevivencia financiera y con la diferenciación. Clasificación JEL: M19.

Resumo O objetivo deste estudo foi analisar a estratégia implementada por 19 microempresas que produzem queijos artesanais nos trópicos mexicanos. A análise foi realizada calculando um índice de estratégia a partir da detecção das ações implementadas nas áreas de colaboração, inovação, canais de marketing, sobrevivência financeira, diferenciação e relacionamento com o consumidor, para comparar a combinação de estratégias com as quais enfrentam uma mudança de mercado. A partir de uma análise não hierárquica de conglomerados, cuja variável de agrupamento foi o índice de estratégia por categoria, o comportamento de cada grupo de microempresas foi diferenciado. Quatro mecanismos resultaram da combinação de estratégias que cada grupo de microempresas realiza. Concluiu-se que, para sobreviver no mercado, essas microempresas têm desenvolvido ações estratégicas diferenciadas, dentre as quais predominam as do canal de vendas, em três dos quatro conglomerados, e as de colaboração, em dois dos quatro conglomerados. Não foram detectadas diferenças entre os grupos quanto às ações relacionadas à sobrevivência e diferenciação financeira.

Abstract The aim of this study was to analyze the strategy implemented by 19 microenterprises that produced artisan cheeses in the tropics of Mexico. The analysis was carried out by calculating a strategy index based on the detection of the actions that microenterprises implemented in the areas of collaboration, innovation, marketing channel, financial survival, differentiation, and consumer relationship, to compare the combination of strategies with those faced in a dynamic market. By means of a non-hierarchical cluster analysis, whose grouping variable was the strategy index by category, the behavior of each group of microenterprises was differentiated. Four mechanisms emerged from the combination of strategies that each group of microenterprises execute. It was concluded that, to remain in the market, these microenterprises have developed differentiated strategic actions, predominantly marketing channel, in three out of four clusters, and collaboration in two out of four clusters. No differences were detected between groups regarding actions related to financial survival and to differentiation.

Abstract: Conventional agriculture with the establishment of monocultures and the indiscriminate use of pesticides negatively impacts soil fertility. Legume cultivation is an alternative to improve soil conditions and produce food. Therefore, the physical and chemical properties of the soil were determined before and after cultivation of Phaseolus vulgaris, Vigna unguiculata and Vigna radiata. Before starting the crop, the producer evaluated the quality of the soil using qualitative visual indicators. Three treatments were established under a randomized complete block design and with analysis of variance the physicochemical properties were compared before and after cultivation. The quality of the soil was moderate both by the visual evaluation and by the chemical analysis carried out. Treatment effects were observed in CIC and Ca values, which decreased after cultures. The polyculture of leguminous species contributes to improving soil conditions.

Resumen: La agricultura convencional con el establecimiento de monocultivos y el uso indiscriminado de plaguicidas impacta de forma negativa la fertilidad del suelo. El cultivo de especies leguminosas es una alternativa para mejorar las condiciones del suelo y producir alimento. Por ello, se determinaron las propiedades físicas y químicas del suelo, antes y después del cultivo de Phaseolus vulgaris, Vigna unguiculata y Vigna radiata. Antes de iniciar el cultivo el productor evaluó la calidad del suelo mediante indicadores visuales cualitativos. Se establecieron tres tratamientos bajo un diseño de bloques completos al azar y por medio del análisis de varianza se compararon las propiedades fisicoquímicas, antes y después del cultivo. La calidad del suelo es moderada tanto por la evaluación visual como por el análisis químico. Se observaron efectos del tratamiento en la CIC y Ca, los cuales disminuyeron después de los cultivos. El policultivo de leguminosas contribuye a mejorar las condiciones del suelo.

ABSTRACT Fasciolosis and paramphistomosis are a major health problem for the livestock economy worldwide. In Colombia, both distomatosis are reported in cattle, particularly in high Andean tropics, with annual economic losses close to COP 40 billion. The goal of this study was to determine the prevalence of fasciolosis and paramphistomosis in cattle from La Candelaria farm, Caucasia (Colombia), and the presence of intermediate host snails. A descriptive cross-sectional study was carried out with non-probability convenience sampling. Stool samples were collected from the animals and the diagnosis was made using the modified Dennis technique. Digenea prevalence were determined according to sex, weight, age, and race. Freshwater snails were collected in the studied area and were identified by morphology. 400 and 66 fecal samples from 178 bovines of the Zebu (Bos indicus), BON (white-eared white) breeds and the cross between them were analyzed. Fasciola hepatica and Paramphistomidae were diagnosed with a prevalence of 2,2% and 30,9%, respectively. Coinfection was diagnosed in 1,1% of the cattle. Both trematodosis were most frequent in females (p = 0,03). Freshwater molluscs Ampullariidae, Physidae and Planorbidae without digenea larval stages were identified. It was concluded that dual-purpose cattle from La Candelaria farm are exposed to F. hepatica and Paramphistomidae and are probably infected on the farm grounds. Paramphistomidae was more prevalent than F. hepatica, which agrees with other studies in herds from the Colombian high Andean tropics. Paramphistomidae was found in all age groups.

RESUMEN En muchos países la fasciolosis y la paramfistomosis representan un grave problema para la salud del sector pecuario. En Colombia hay registros de ambas distomatosis en bovinos, la mayoría en el trópico alto andino, las cuales generan pérdidas econômicas anuales cercanas a 40 000 000 000 COP. El objetivo de esta investigación fue determinar la prevalencia de fasciolosis y paramfistomosis en vacunos de la hacienda La Candelaria, Caucasia (Colombia), y la presencia de caracoles hospederos intermediarios. Para cumplirlo, se realizó un estudio descriptivo de corte transversal con muestreo no probabilístico por conveniencia. Se recolectaron heces de los animales y se hizo el diagnóstico mediante la técnica modificada de Dennis. Se establecieron las prevalencias de los digeneos de acuerdo con el sexo, peso, edad y raza. Se recolectaron caracoles dulciacuícolas en la zona estudiada y se identificaron por morfologia. Se analizaron 466 muestras fecales de 178 bovinos, de las razas Cebú (Bos indicus), BON (blanco orejinegro) y del cruce entre ellas. Se diagnosticaron F. hepatica y Paramphistomidae con prevalencias del 2,2% y 30,9%, respectivamente. En el 1,1% de los vacunos se diagnosticó coinfección. Ambas trematodosis prevalecieron en las hembras (p = 0,03). Se identificaron moluscos dulciacuícolas Ampullariidae, Physidae y Planorbidae sin estadios larvarios de digeneos. Se concluyó que los bovinos de doble propósito de la hacienda La Candelaria están expuestos a F. hepatica y Paramphistomidae, y, probablemente, se infectan en los predios de la hacienda. Paramphistomidae es más prevalente que F. hepatica, lo cual concuerda con lo descrito en algunos estudios realizados en hatos del trópico alto andino colombiano. Paramphistomidae se encontró en todos los grupos etarios.

RESUMEN La ganadería de leche del trópico alto colombiano utiliza una alta relación de forraje concentrado en la dieta diaria, la cual, en la mayoría de los casos, deja márgenes económicos poco favorables al productor siendo necesaria la búsqueda de alternativas para la alimentación que ayuden a solventar esta problemática. El objetivo del presente trabajo fue evaluar la producción, calidad de la leche y hacer un análisis económico de vacas Holstein, suplementadas con ensilaje de botón de oro (EBO) o ensilaje de maíz (EMA). Se seleccionaron 10 vacas Holstein con características homogéneas y se conformaron dos grupos: un grupo fue suplementado con el tratamiento EMA y el otro con EBO, en un diseño de sobrecambio. Se evaluó la producción de leche/vaca/día sin ajustar y ajustada al 4 % de grasa, la calidad composicional de la leche (% y kg/vaca/día), la eficiencia alimenticia (EA), la eficiencia energética (EE) y se realizó un análisis económico. No hubo diferencias estadísticas significativas (p>0,05) en el consumo de materia seca de ensilaje entre tratamientos, pero sí en la producción de leche, los kg de grasa y proteína/vaca/día, y en la EA (p< 0,05), con diferencia a favor de EBO. Así mismo, el costo de producción del litro de leche y la diferencia ventas-costos por vaca/día estuvieron a favor del tratamiento EBO. Los resultados sugieren que el EBO es una alternativa viable productiva y económicamente, en la suplementación de vacas lactantes en el trópico alto colombiano.

ABSTRACT The dairy farming in the Colombian highland tropic uses a high ratio of concentrate forage in the daily diet, which, in most cases, leaves unfavorable economic margins for the producer, making it necessary to search alternatives for feeding that help to solve this problem. The aim of this work was to evaluate the milk production and quality, and to make an economic analysis of Holstein cows, supplemented with wild sunflower silage (EBO) or corn silage (EMA). Ten Holstein cows with homogeneous characteristics were selected and two groups were formed: one group was supplemented with EMA treatment and the other with EBO, in an over-exchange design. The milk production/cow/day without adjusting and adjusted to 4 % fat, the compositional quality of the milk (% and kg/cow/day), the feed efficiency (EA), the energy efficiency (EE) and an economic analysis was carried out. There were no statistically significant differences (p>0,05) in the consumption of silage dry matter between treatments, but there were in the milk production, the kg of fat and protein/cow/day, and in the EA (p<0,05), with a difference in favor of EBO. Likewise, the cost of production per liter of milk and the difference between sales and costs per cow/day were in favor of the EBO treatment. The results suggest that EBO is a productive and economically viable alternative in the supplementation of lactating cows in the Colombian highland tropic.