RESUMEN El estudio de las sensaciones térmicas reviste importancia desde el punto de vista bioclimático, pues es una muestra objetiva de la influencia del clima sobre el hombre. La reciente verificación del pronóstico de Temperatura Efectiva Equivalente implementado en el Sistema de Pronóstico Inmediato (SisPI) amerita efectuar una evaluación de dicho modelo para el pronóstico de las sensaciones térmicas. Es por ello que en la presente investigación se plantea como objetivo principal evaluar la efectividad del pronóstico de las sensaciones térmicas del SisPI durante el 2019. Para la verificación del pronóstico de esta variable fueron confeccionadas tablas de contingencia multicategoría para los horarios 7:00 a.m. y 1:00 p.m. Se procesaron los datos y fueron calculados los estadígrafos correspondientes para su evaluación. Como conclusiones se tiene que el SisPi mostró una buena habilidad para el pronóstico de las sensaciones térmicas a partir del índice bioclimático Temperatura Efectiva Equivalente en Cuba durante el 2019. En el horario de las 07:00 am los mayores aciertos fueron obtenidos en el pronóstico de las sensaciones térmicas ligeramente fría y confortable y a la 01:00 pm, para la sensación térmica muy calurosa.

ABSTRACT The study of thermal sensations holds importance from a bioclimatic perspective, as it provides an objective measure of the influence of climate on humans. The recent validation of the Effective Equivalent Temperature forecast implemented in the Immediate Forecast System (SisPI) necessitates an evaluation of this model for the prediction of thermal sensations. Therefore, the primary objective of this research is to assess the effectiveness of SisPI's thermal sensation forecast during 2019. To verify the forecast for this variable, contingency tables for multiple categories were constructed for the 7:00 a.m. and 1:00 p.m. time slots. The data were processed, and relevant statistics were computed for evaluation. The conclusions drawn from this study indicate that SisPI exhibited good proficiency in forecasting thermal sensations using the Effective Equivalent Temperature bioclimatic index in Cuba during 2019. At 7:00 a.m., the highest accuracy was achieved in forecasting slightly cold and comfortable thermal sensations, while at 1:00 p.m., it excelled in predicting very hot thermal sensations.

Resumen Por lo general, las investigaciones que atienden el fenómeno del confort térmico humano basadas en el enfoque adaptativo, difunden sus hallazgos detallando con suficiente precisión la metodología utilizada y los resultados obtenidos; sin embargo, es limitada la explicación que permite enterar sobre los métodos y los criterios empleados en el procesamiento estadístico de datos que permitió llegar a los resultados referidos. Los métodos estadísticos comúnmente utilizados para interpretar y entender el fenómeno del confort térmico son de tipo univariable y, por lo regular, se basan en la regresión lineal para predecir el comportamiento de una variable a partir de la variación de otra; entre otros, se pueden identificar el método de la regresión lineal simple y el método de Medias por Intervalos de Sensación Térmica, aunque también es posible encontrar estudios que se basan en el método sugerido en la ANSI/ASHRAE 55. Con lo anterior, en este documento se describe un procedimiento que permite procesar estadísticamente los datos a partir de tres etapas: Captura de la base de datos, preparación de la base de datos y correlación de los datos. En cada caso se ofrece precisión de los pasos a seguir y, en algunos, diferentes alternativas estadísticas que permiten ofrecer certidumbre en la búsqueda de los resultados. A partir de diferentes estudios especializados en confort térmico es posible identificar que el método de Medias por Intervalos de Sensación Térmica ofrece resultados con mayor consistencia y causalidad respecto a la sensación térmica percibida y su correspondencia fenomenológica con el monitoreo de las condiciones ambientales de estudio. Adicionalmente, como complemento a este documento, se comparte una hoja de cálculo que presenta los métodos que en él se describen.

Abstract Existing research literature on adaptive thermal comfort studies shows the methodology used and results obtained; however, the information for data analysis is reduced. Methods commonly used to interpret and understand the thermal comfort phenomenon are univariate type and, usually, use the linear regression to predict the behavior of one variable from the variation of other; among others, Simple Linear Regression method and Averages by Thermal Sensation Interval method can be identified, although it is also possible to find studies based on the ANSI/ASHRAE 55 method or on machine-learning algorithms. This document describes a procedure that allows three-stages data to be statistically processed: Database capture, Database preparation, and Data Correlation. In each case, the steps to be followed are specified and different statistical alternatives are indicated to achieve certainty in the results. From different studies specialized in thermal comfort, it is possible to identify that the Averages by Thermal Sensation Interval method offers results with greater consistency and causality regarding the perceived thermal sensation and its phenomenological correspondence with the monitoring of the environmental conditions. As a complementary resource, a personalized spreadsheet whit the three methods described in this paper is including.

Resumen Los estudios sobre confort térmico desarrollados bajo las bases metodológicas del enfoque adaptativo advierten una dependencia importante de la sensación térmica de los sujetos respecto a las condiciones climáticas exteriores del lugar habitado. Las condiciones adversas del ambiente térmico pueden influir negativamente en el bienestar, la eficiencia y el confort de los sujetos, lo que deriva en la subutilización de los espacios cuyas condiciones higrotérmicas son inapropiadas para la actividad para la que fueron construidos. El objetivo de este trabajo consiste en estimar el rango de confort higrotérmico para espacios exteriores en dos bioclimas representativamente extremos en México: Cálido-húmedo y semifrío-seco. El primero presenta una temperatura media anual de 26.2 °C y una precipitación total anual de 1,094.8 mm, mientras que el segundo, una de 17.3 °C y una de 217.3 mm, respectivamente. Los estudios son de tipo correlacional y fueron analizados con 605 evaluaciones y el registro simultáneo de la temperatura, la humedad relativa y la velocidad de viento durante el periodo cálido. Los cuestionarios aplicados se diseñaron con base en la ISO 10551 y la ANSI/ASHRAE 55; asimismo, los instrumentos de medición física se establecieron a partir de la ISO 7726. Los datos recabados fueron procesados estadísticamente con el método de Medias por Intervalos de Sensación Térmica. El rango de confort higrotérmico estimado para el bioclima cálido-húmedo fue de 21.8 °C a 34.9 °C para la temperatura y de 38.3 % a 85.8 % para la humedad relativa, mientras que para el semifrío-seco fue de 19.4 °C a 25.0 °C y de 54.2 % a 84.0 %, respectivamente. Estas estimaciones responden a la adaptación que las personas presentan con su ambiente inmediato, a razón de las condiciones climáticas locales de cada lugar y el periodo de evaluación estudiado.

Abstract Thermal comfort studies developed from the adaptive approach note an important dependence of the subjects' thermal sensation with the outdoor climatic conditions of the inhabited space. Adverse thermal environment can negatively influence the well-being, performance and comfort of the subjects, which results in the underutilization of spaces whose hygrothermal conditions are inappropriate for the activity for which they were built. This paper shows the estimation the hygrothermal comfort range for outdoor spaces in two representatively extreme bioclimates in Mexico: Warm-humid and semi-cold-dry. The first one has an annual mean temperature of 26.2 °C and a total annual precipitation of 1,094.8 mm, while the second one has an annual mean temperature of 17.3 °C and a total annual precipitation of 217.3 mm. The studies are correlational type and were analyzed with 605 evaluations and the simultaneous recording of temperature, relative humidity and wind speed, during the warm period. Used questionnaires were designed based on ISO 10551 and ANSI/ASHRAE 55; and environmental measurement instruments were based on ISO 7726. Data were processed by Averages by Thermal Sensation Intervals method. For the warm-humid bioclimate, the thermal comfort range results from 21.8 °C a 34.9 °C and the hydric comfort range was from 38.3 % a 85.8 %, while for the Semi-cold-dry bioclimate it was from 19.4 °C a 25.0 °C and 54.2 % a 84.0 %, respectively. These estimates respond to the adaptation that people present with their immediate environment, due to the local climatic conditions of each place and the study period.

Abstract The Ecuadorian government delivers social housing through total or partial financing programs throughout the Ecuadorian territory. The present work has the following objectives: to evaluate the thermal-energetic performance of the social housing in the Rocafuerte Pichota housing development in Rocafuerte canton in the province of Manabí, by means of in-situ temperature measurements; to perform simulations of the housing using the SIMEDIF program by entering data to monitor the thermal conditions of the housing, and to correlate the measurements-simulations; and to determine the thermal perception of the users of the housing in the development. The results showed that the house has a poor thermal-energetic performance, due to the climate conditions of the area and the construction system of the house. In spite of the diagnosis of the thermal performance of the house, the users rate the comfort of their house as good.

Resumen El gobierno ecuatoriano hace entrega de viviendas de interés social mediante programas de financiamiento total o parcial en todo el terrritorio ecuatoriano. El presente trabajo tiene como objetivos: Evualuar el comportamiento térmico-energetico de la vivienda social en la urbanización Rocafuerte Pichota del cantón Rocafuerte de la provincia de Manabí, mediante mediciones in-situ de temperatura; realizar simulaciones de la vivienda mediante el programa SIMEDIF ingresando datos para monitorizar las condiciones térmicas de la vivienda, además de correlacionar las mediciones-simulaciones; y, determinar la percepción térmica de los usuarios de la vivienda de la urbanización. Los resultados mostraron que la vivienda tiene un deficiente rendimiento térmico-energético, esto debido las condiciones de clima de la zona y al sistema constructivo de la vivienda. A pesar del diagnóstico del rendimiento térmico de la vivienda, los usuarios califican al confort de su vivienda como bueno.

Abstract We evaluated the influence of a 32-day camping in Antarctica on physical performance and exercise-induced thermoregulatory responses. In Brazil, before and after the Antarctic camping, the volunteers performed an incremental exercise at temperate conditions and, two days later, an exercise heat stress protocol (45-min running at 60% of maximum aerobic speed, at 31°C and 60% of relative humidity). In Antarctica, core temperature was assessed on a day of fieldwork, and average values higher than 38.5°C were reported. At pre- and post-Antarctica, physiological (whole-body and local sweat rate, number of active sweat glands, sweat gland output, core and skin temperatures) and perceptual (thermal comfort and sensation) variables were measured. The Antarctic camping improved the participants’ performance and induced heat-related adaptations, as evidenced by sweat redistribution (lower in the chest but higher in grouped data from the forehead, forearm, and thigh) and reduced skin temperatures in the forehead and chest during the exercise heat stress protocol. Notwithstanding the acclimatization, the participants did not report differences of the thermal sensation and comfort. In conclusion, staying in an Antarctic camp for 32 days improved physical performance and elicited physiological adaptations to heat due to the physical exertion-induced hyperthermia in the field.

Abstract Neuropathic pain is generally characterised by an abnormal sensation (dysesthesia), an increased response to painful stimuli (hyperalgesia), and pain in response to a stimulus that does not normally provoke pain (allodynia). The present study was designed to investigate the effect of trazodone (5mg/kg and 10mg/kg) on peripheral neuropathic pain induced by partial sciatic nerve ligation in rats. Mechanical hyperalgesia, cold allodynia and thermal hyperalgesia were assessed by performing the pinprick, acetone, and hot plate tests, respectively. Biochemically, lipid peroxidation level and total calcium levels were measured. However, trazodone administration (5 and 10 mg/ kg i.p.) for 21days significantly diminished partial sciatic nerve ligation-induced neuropathic pain along with areduction in oxidative stress and calcium levels. The results of the present study suggest that trazodone is effective in attenuating partial sciatic nerve ligation-inducedpainful neuropathic states, which may be attributed to decreased oxidative stress and calcium levels.

Resumen Análisis energético y de confort térmico usando EnergyPlus®, para un prototipo de residencia unifamiliar ubicada en Foz do Iguaçu, zona climática 3A-Brasil. Mediante la sensación térmica estimada en el interior de la residencia, se analizó la ventilación natural, donde se comparó un sistema considerando las infiltraciones de aire del modelo constructivo con otro de ventilación selectiva programada; fueron propuestos dos sistemas de calefacción, ventilación y aire acondicionado (HVAC), siendo un sistema Split y un sistema de flujo de gas refrigerante variable (VRF). Los resultados mostraron que, aunque los casos de ventilación natural influyeron en la temperatura y humedad interna, el confort térmico en la región no es viable sin el uso de mecanismos artificiales. Así, el sistema VRF mostró un ahorro energético anual para aire acondicionado del 14,76% y un ahorro en el consumo energético total del 10,11% al año en comparación con el sistema Split, siendo económicamente más rentable.

Abstract Energy performance and thermal comfort through EnergyPlus®, for a prototype of a single-family residence located in Foz do Iguaçu, climate zone 3A-Brazil. Using the estimated thermal sensation inside the house, natural ventilation was analyzed, where a system was compared considering the air infiltrations of the construction model with another of programmed selective ventilation; and two heating, ventilation, and air conditioning (HVAC) systems were proposed, being a Split system and a variable refrigerant gas flow (VRF) system. The results showed that, although the cases of natural ventilation influenced internal temperature and humidity, thermal comfort in the region is not feasible without the use of artificial mechanisms. The VRF system showed annual energy saving to the air conditioning of 14.76% and saving in the total annual energy consumption of 10.11% about the Split system, in addition to more economic profitability.

Abstract This work is taken up to evaluate the relationship between the thermal comfort of spectators and athletes and the prevailing meteorological conditions during Rio 2016 Olympic Games. Empirical and physiological thermal comfort indices are calculated from data collected from an automatic weather station installed near the Olympic Stadium and interviews with the spectators. The study period was marked by a gradual rise in air temperature and by the occurrence of two significant weather events associated with wind gusts, which caused disturbances in some areas of the competitions. ET and NET were below the air temperature, indicating that both humidity and wind contributed to the reduction of the human-biometeorological indices. Majority of the interviewed persons reported comfortable sensation and weather conditions. These perceptions corroborate results of the thermal comfort indices calculated for these resting spectators. The comfort indices calculated for the athletes with high level of physical activity showed that PET estimated hotter thermal sensation those for the individuals at rest, indicating that the physical type of a person may strongly influence the thermal sensation and comfort during intense physical activity. Increasing trend observed in all the indices of human thermal comfort during the period of study shows consistency among them.

Resumo O conforto térmico apresenta elevada importância para a conservação de energia em edificações, bem como para a satisfação e o desempenho dos usuários. O principal objetivo deste trabalho é avaliar o efeito da umidade do ar no conforto térmico de usuários de edificações de escritórios localizadas no clima subtropical úmido de Florianópolis/SC. Com base em dados previamente coletados em campo, foram efetuadas análises estatísticas considerando a umidade do ar e as respostas subjetivas dos usuários obtidas por meio de um questionário eletrônico. Analisou-se a percepção térmica e da umidade do ar de ocupantes de uma edificação com sistema central de ar-condicionado e duas edificações híbridas, onde houve alternância entre os modos de operação por ventilação natural e por ar-condicionado. Os resultados obtidos indicam ausência de relação entre a razão de umidade e a percepção térmica, no entanto mostram significativa influência da sensação de umidade e da preferência quanto à umidade sobre o conforto térmico. Ademais, assim como apontam outros autores, confirmou-se a importância da utilização da umidade absoluta ao invés da umidade relativa nas análises de conforto térmico.

Abstract Thermal comfort is highly important not only for energy conservation in buildings, but also for users’ satisfaction and performance. The main objective of this project is to assess the effect of air humidity on the thermal comfort of users of office buildings located in a humid subtropical climate, in Florianópolis/SC, southern Brazil. Based on field data previously collected, statistical analyses were performed considering the air humidity and users’ subjective responses obtained by means of an electronic questionnaire. The thermal perception and the air humidity perception of occupants of a building with central air-conditioning system and two mixed-mode buildings, in which there was alternation between the natural ventilation mode and the air-conditioning mode, were analysed. The results obtained indicate no relation between humidity ratio and thermal perception, however, a significant influence of humidity sensation and humidity preference on thermal comfort was observed. In addition, the study confirmed, as other authors had already pointed out, the importance of the use of absolute humidity instead of relative humidity in thermal comfort analyses.

Resumo Uma parcela considerável das pesquisas sobre o conforto térmico não considera a dinâmica da relação entre os usuários e a edificação, bem como há poucos estudos sobre conforto térmico e o idoso, especialmente em clima tropical. Esta pesquisa abordou a sensação e a percepção térmica em conjunto habitacional com as estratégias de adaptação ao ambiente, tendo como população indivíduos acima de 60 anos. Para isso, foram coletados dados mediante entrevistas semiestruturadas com 90 residentes de três conjuntos habitacionais para idosos, de caráter social e mesmo projeto arquitetônico, localizados nas cidades paraibanas de João Pessoa, Campina Grande e Cajazeiras. Os dados foram analisados por meio de técnicas estatísticas descritivas e inferenciais. Os idosos apresentaram tendência a preferir condições térmicas mais amenas àquelas vivenciadas por eles na habitação em análise. A ventilação natural é considerada uma variável importante para o conforto térmico, contudo os entrevistados relatam fechar as esquadrias para evitar a entrada de insetos e animais, dificultando a ventilação natural. Também foi identificado que fatores culturais e a necessidade de segurança interferem no fechamento das aberturas. Não foram encontradas correlações significativas entre o sexo dos entrevistados e suas respostas.

Abstract A considerable portion of the research on thermal comfort fails to undertake a comprehensive analysis including the relationship between residents and their buildings. It is also noteworthy that there are but a few studies on thermal comfort and the elderly, especially in tropical climates. Thus, this research study looks into sensation and thermal perception alongside strategies of adaptation to the environment, investigating a population of individuals over 60 years old, forming a sample of 90 respondents. The object of this study comprised 3 social housing units for the elderly located in the cities of Paraíba, João Pessoa, Campina Grande, and Cajazeiras. Data were collected through semi-structured interviews, and analysed using descriptive and inferential statistical techniques. The researchers found that the elderly showed a preference for thermal environmental conditions milder than those prevailing at the time of interview. Natural ventilation is normally considered an important variable for thermal comfort, however, the respondents reported closing openings to prevent the entry of insects and animals, making natural ventilation difficult, and contributing to their thermal discomfort. It was also found that both cultural and security factors influence the closing of doors and windows. No significant correlation was found between the respondents' gender and their answers.

Resumo Alterações no uso e ocupação do solo das cidades tem consequências diretas no campo térmico urbano, cujas características físicas e microclimáticas tornam-se atrativos à convivência humana. Esta pesquisa teve como objetivo analisar a variação de um índice biometeorológico e estudar quantitativamente o ciclo diurno do conforto térmico humano em Maceió-AL, por meio de dados horários disponibilizados pela estação meteorológica automática do Instituto Nacional de Meteorologia (INMET) entre os anos de 2004 a 2015. Em média, observa-se sensação de conforto das 00 às 09 horas UTC; das 11 às 20 UTC prevalece a sensação de desconforto térmico pelo calor. A partir das 21 UTC o desconforto devido ao calor vai apresentando uma diminuição e o conforto começa a aumentar, prevalecendo essa sensação, não sendo identificados casos de desconforto ou estresse devido ao frio. é comum, a depender da época do ano, ocorrência de horas de estresse pelo calor entre 10 a 19 UTC, com maior frequência das 15 às 17 UTC. Apesar de constatados desconforto e estresse por calor, predomina na maior parte das horas do dia condições de conforto, não sendo observados em todo o período de estudo nenhum caso de desconforto por frio.

Abstract Changes in land use and occupation in cities have direct consequences in the urban thermal field, whose physical and microclimate characteristics become attractive to human coexistence. This research aimed to analyze the variation of a biometeorological index and to quantitatively study the diurnal cycle of human thermal comfort in Maceió-AL, using hourly data provided by the automatic meteorological station of the National Institute of Meteorology (INMET) between the years 2004 to 2015. On average, there is a feeling of comfort from 00 to 09 UTC; from 11 to 20 UTC the sensation of thermal discomfort by heat prevails. After 21 UTC, the discomfort due to heat decreases and comfort begins to increase, with this feeling prevailing, with no cases of discomfort or stress due to the cold being identified. It is common, depending on the time of year, for hours of heat stress between 10 to 19 UTC, more frequently from 15 to 17 UTC. Despite discomfort and heat stress, comfort conditions prevail in most hours of the day, with no case of discomfort due to cold being observed throughout the study period.

ABSTRACT This paper aims to compare different bioclimatic indices in the conditions of Cuba and determine their relationship with the meteorological variables involved. For this, several bioclimatic indexes of thermal comfort are calculated (Effective Temperature, Equivalent Effective Temperature, Heat Index, Humidex, Apparent Temperature, Windchill, Standard Effective Temperature, Effective Physiological Temperature and the Universal Thermal Climate Index) using the tri-hour meteorological data of six stations. The statistical relationships between these and the main meteorological variables that are involved in their calculation are analyzed, as well as their differences with the ambient temperature. The complex indices studied represented very well the stimulation of solar radiation in thermal sensations in Cuba. The comparison between complex and empirical indices in Cuba showed the greatest statistical relationships between the Universal Thermal Climate Index and the Equivalent Effective Temperature, although the last one best represents thermal sensations under humid environments confirming its proper use it the country. The effective temperatures obtained by each index studied differ between them and the real ambient temperature, so these values are not really important for the user but the classification of the thermal sensation and its influence on people.

RESUMEN El presente trabajo tiene como objetivo comparar diferentes índices bioclimáticos en las condiciones de Cuba y determinar su relación con las variables meteorológicas involucradas. Para esto se calculan varios índices bioclimáticos de confort térmico (Temperatura Efectiva, Temperatura Efectiva Equivalente, Heat Index, Humidex, Temperatura Aparente, Windchill, Temperatura Efectiva Estándar, Temperatura fisiológica efectiva y el Índice Térmico Universal del Clima) utilizando los datos trihorarios de 6 estaciones meteorológicas. Se analizan las relaciones estadísticas entre estos y las principales variables meteorológicas que intervienen en su cálculo, así como las diferencias de estos con la temperatura ambiente. Los índices complejos estudiados representaron muy bien el estímulo de la radiación solar en las sensaciones térmicas en Cuba. La comparación entre índices complejos y empíricos en Cuba mostró las mayores relaciones estadísticas entre el Índice Térmico Universal del Clima y la Temperatura Efectiva Equivalente, aunque este último representa mejor las sensaciones térmicas bajo ambientes húmedos confirmando su uso adecuado el país. Las temperaturas efectivas obtenidas por cada índice estudiado difieren en mayor o menor medida entre ellas y la temperatura ambiente real por lo que estos valores no son realmente importantes para el usuario sino la clasificación de la sensación térmica y su influencia en las personas.

Resumo Sabe-se que, com o envelhecimento, acontecem alterações fisiológicas que comprometem negativamente a sensação térmica do indivíduo. No entanto, a sensação de conforto térmico de pessoas idosas em ambientes residenciais tem sido pouco explorada no Brasil, principalmente em ambientes residenciais. Nesse contexto, quais seriam os parâmetros para avaliar a qualidade térmica de ambientes residenciais para pessoas idosas? Para responder a essa questão determinaram-se os parâmetros de conforto térmico para pessoas idosas em ambiente residencial na cidade de Campina Grande, localizada no estado da Paraíba, Brasil. A pesquisa, de natureza empírica, adotou a estratégia de múltiplos métodos, com entrevista estruturada para obter os dados das variáveis individuais e subjetivas, e medição dos dados das variáveis ambientais por meio de instrumentos e equipamentos especializados. A técnica estatística de estimativa de probabilidades (probits) utilizada para determinar os parâmetros de conforto térmico comprovou a preferência das pessoas idosas por ambientes mais aquecidos. A partir dos resultados é possível contribuir com o planejamento de ambientes residenciais mais confortáveis para pessoas idosas, mediante avaliações pós-ocupação (APO) e simulações de desempenho térmico de edificações em fase de concepção projetual.

Abstract Ageing, as we know, involves a series of physiological changes that have a negative impact on the individual's thermal perception. However, thermal comfort for the elderly has received little attention from researchers in Brazil, especially regarding the elderly people's own homes. In this context, what parameters can be applied to assess thermal quality in elderly people's homes? To answer this question, thermal comfort parameters have been determined for elderly people in their homes in the city of Campina Grande, Paraíba State, Brazil. For this empirical research, a multiple-method strategy was implemented through the use of structured interviews to collect data concerning individual and subjective variables, as well as the measurement of data concerning environmental variables through the use of dedicated tools and equipment. The probit model for estimating probabilities was used to determine the parameters of thermal comfort, confirming the preference of elderly people for warmer environments. The results can help design home environments that are more comfortable for elderly people, through post-occupancy evaluation (POE) and simulations of the thermal performance of houses or building during the designing stage.

Resumen Introducción. La precipitación, temperatura, radiación y humedad relativa varían según la altura, esto provoca la presencia de microclimas que afectan la productividad de los animales. Objetivo. Asociar las condiciones climáticas presentes en el sistema productivo con la producción láctea de un hato jersey puro en dos pisos altitudinales de la provincia de Cartago, Costa Rica. Materiales y métodos. De forma retrospectiva, durante el año 2016, se evaluó la información productiva de dos sistemas ubicados a 660 y 1800 msnm. Del primero se analizaron los registros de 61 animales durante doce años (12 083 datos); mientras que en el segundo se analizaron las lactancias de 387 animales en cinco años (13 820 registros). Las observaciones incluyeron: identificación del semoviente, día de generación del registro, mes, año, producción de leche diaria, días de lactancia, número de partos, edad del animal, temperatura, precipitación, radiación solar y humedad relativa promedio. Resultados. Los días de lactancia, el número de lactancia (3a-5a), la edad del animal (3,7 a 5,8 años) y el número de partos afectaron la producción de leche diaria en ambas fincas (p<0,001). A 1800 m, cuando la precipitación fue mayor a 5 pero menor o igual a 10 mm día-1 y la humedad relativa mayor a 80 pero menor a 90 % día-1 (p<0,001), la producción de leche disminuyó. En cambio, a 660 m el efecto provino de la humedad relativa menor o igual a 70 %. La temperatura ambiental tuvo un efecto significativo sobre ambas altitudes. Conclusiones. Las condiciones de temperatura, humedad, precipitación y radiación en cada ecosistema, generaron diferencias en la productividad de los animales, relacionadas con el tipo de forraje y la sensación térmica a la que estaba expuesto el ganado, lo cual provocó estrés por calor o por frío.

Abstract Introduction. Precipitation, temperature, radiation, and relative humidity vary according to height, this causes the presence of microclimates that affect the productivity of the animals. Objective. Associate the climatic conditions present in the productive systems with dairy production of a pure Jersey herd in two altitudinal floors of the province of Cartago, Costa Rica. Materials and methods. In retrospect, during the year 2016, the productive information of two dairy farms, located at 660 and 1800 m.a.s.l. was evaluated. From the first farm, the records of 61 animals in a twelve-year period (12,083 data) were analyzed; while in the second, the lactations of 387 animals in a five-year period (13,820 records) were analyzed. Observations included: identification of the cow, day of generation of the record, month, year, daily milk production, lactation days, calving number, animal age, temperature, precipitation, solar radiation and average relative humidity. Results. The lactation days, the lactation number (3-5), the age of the animal (3.7 to 5.8 years), and the calving number affected the daily milk production on both farms (p<0.001). At 1800 m, when the precipitation was greater than 5 but less than or equal to 10 mm day-1 and the relative humidity greater than 80 but less than 90 % day-1 (p<0.001), milk production decreased. On the other hand, at 660 m the effect came from relative humidity less than or equal to 70 %. The environmental temperature had a significant effect in both altitudes. Conclusion. The conditions of temperature, humidity, precipitation, and radiation in each ecosystem, generated differences in the productivity of the animals, related to the type of forages and the thermal sensation to which the cattle was exposed, which caused heat or cold stress.

Abstract The influence of environmental factors in dairy cows was evaluated. A database that included twelve years (2005-2016) was used. The variables ambient temperature, relative humidity, rainfalls and temperature - humidity index in heat stress levels were studied. The INFOSTAT program was used for the analysis. The results show a high level of the average annual maximum temperature (30.2oC). The same performance showed the relative humidity (76.0 %), while rainfalls did not behave in the same way, and tended to decrease by 150 mm during the analyzed period. The average temperature - humidity index was 78 in the period 2005-2016, with marked contrast in its annual distribution. Between November and March, the animals were in slight stress, as opposed to the June-September period, in which the values reached levels of 83, so the animals were exposed to severe stress conditions. During the study period, the average annual relative humidity in the research area was 76 %. Seven months maintained their average monthly value above this value (78 %). In general, an area with high relative humidity can be considered, which has its direct effect on thermal sensation and the temperature-humidity index, which considerably affects the animal welfare. It was proved that during the studied period (2005-2016) the cows were with a level from slight to severe heat stress in all months of the year, which could affect homeostasis and animal welfare.

Resumen Se evaluó la influencia de factores ambientales en vacas lecheras. Se utilizó para ello una base de datos que comprendió doce años (2005-2016). Se estudiaron las variables temperatura ambiente, humedad relativa, precipitaciones e índice de temperatura y humedad en los niveles de estrés calórico. Para el análisis se usó el programa INFOSTAT. Los resultados muestran elevado valor de la temperatura máxima media anual (30.2oC). Igual comportamiento presentó la humedad relativa (76.0 %), mientras que las precipitaciones no se comportaron de igual forma, y tendieron a disminuir en 150 mm durante el período analizado. El promedio del índice de temperatura y humedad fue de 78 en el período 2005-2016, con contraste marcado en su distribución anual. Entre noviembre y marzo, los animales se encontraron en estrés leve, en oposición con el período junio-septiembre, en el que se alcanzaron valores de 83, por lo que los animales estuvieron expuestos a condiciones graves de estrés. Durante el período de estudio, la humedad relativa media anual en el área de investigación fue 76 %. Siete meses mantuvieron su valor medio mensual por encima de este valor (78%). En sentido general, se puede considerar una zona con elevada humedad relativa, que tiene su efecto directo en la sensación térmica y el índice de temperatura y humedad, lo que afecta considerablemente el bienestar animal. Se comprobó que durante el período estudiado (2005-2016) las vacas se encontraron en estrés térmico de leve a grave en todos los meses del año, lo que pudiera afectar la homeostasis y el bienestar animal.