Key points for the thermal comfort of water buffaloes in Eastern Amazon / Pontos-chave do conforto térmico de bubalinos na Amazônia Oriental

This study presented relevant aspects about the Amazonian environment and how it impacts the thermal comfort of domestic buffaloes (Bubalus bubalis) raised in the Eastern Amazon. Furthermore, strategies for monitoring and mitigating animal heat stress are presented, based on research results with the species. Although domestic buffaloes are considered adaptable animals, exposure to intense solar radiation causes thermal discomfort. This condition is expressed in biophysical indicators, in metabolic, endocrine, behavioral responses, and in body thermographic patterns. Therefore, the biometeorological monitoring of production is crucial to support decision-making regarding environmental management strategies, genetic selection of thermotolerant individuals, and increase in animal welfare. Lastly, the use of silvopastoral systems can help to provide higher thermal comfort, which is a condition that directly impacts the productivity of milk and meat buffaloes when they are raised in tropical regions, such as in the Eastern Amazon.

Objetivou-se apresentar aspectos relevantes sobre o ambiente amazônico e como este impacta no conforto térmico de búfalos domésticos (Bubalus bubalis) criados na Amazônia Oriental. Adicionalmente, são apresentadas estratégias para monitoramento e mitigação do estresse térmico animal, a partir de resultados de pesquisa com a espécie. Apesar dos búfalos domésticos serem considerados animais adaptáveis, a exposição à intensa radiação solar provoca desconforto térmico. Essa condição é expressa em indicadores biofísicos, nas respostas metabólicas, endócrinas, comportamentais e nos padrões termográficos corporais. Assim, o monitoramento biometeorológico da produção é crucial para subsidiar tomadas de decisão em relação a estratégias de manejo ambiental, seleção genética de indivíduos termotolerantes e incremento do bem-estar animal. Por fim, o uso de sistemas silvipastoris pode auxiliar na oferta de maior conforto térmico, que é uma condição que impacta diretamente na produtividade de bubalinos de leite e carne, quando estes são criados em regiões tropicais, como na Amazônia Oriental.

The low-temperature effect on sports regeneration / O efeito da baixa temperatura na regeneração esportiva

Abstract Introduction Intense physical activity and increased exercise significantly reduce the body's adaptive capacity, negatively affect the recovery processes of athletes, and can significantly impair athletic performance. Objective To identify how low temperatures can affect the regenerative processes in athletes, assess the effectiveness and feasibility of cold therapy in sports, and identify the key parameters that determine the effectiveness of the stated recovery method. Methods A systematic review of studies related to the use of cold therapy in sports guided by the Cochrane Handbook for Systematic Reviews of Interventions, and reported through the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The scientific material was selected by finding keywords and phrases, including "the effect of cold on athletes", "athletes' recovery", "cold therapy", etc. Following the selection criteria, only 30 studies were included. Results Cold exposure has significant benefits for sports regeneration, including pain relief (100%), inflammation reduction (93%), and restoration of sprint capabilities (89%). However, its impact on muscle strength (33%), endurance (11%), and lactate reduction (8%) is more limited. It moderately improves the psycho-emotional state (65-75%). Conclusion The use of low temperatures in sports has a beneficial effect on the recovery of sports performance for at least 24 hours after intense physical activity (training).

Resumo Introdução A atividade física intensa e o aumento do exer-cício reduzem significativamente a capacidade de adaptação do organismo, afetam negativamente os processos de recu-peração dos atletas e podem prejudicar significativamente o desempenho atlético. Objetivo Identificar como as baixas temperaturas podem afetar os processos regenerativos dos atletas, avaliar a eficácia e a viabilidade da terapia pelo frio no esorte e identificar os parâmetros-chave que determinam a eficácia do método de recuperação indicado. Métodos Revisão sistemática de estudos relacionados com a utilização da terapia pelo frio no esporte, orientada pelo Manual Cochrane para Revisões Sistemáticas de Intervenções e reportada através dos Preferred Reporting Items for Systematic Reviews and Meta-Analyses. O material científico foi selecionado através da pesquisa de palavras-chave e frases, incluindo "o efeito do frio nos atletas", "recuperação dos atletas", "terapia pelo frio", etc. Seguindo os critérios de seleção, foram incluídos apenas 30 estudos. Resultados A exposição ao frio tem benefícios significativos para a regeneração esportiva, incluindo o alívio da dor (100%), redução da inflamação (93%) e restauração das capacidades de sprint (89%). No entanto, o seu impacto na força muscular (33%), na resistência (11%) e na redução do lactato (8%) é mais limitado. Há uma melhora moderada sobre o estado psico-emocional (65-75%). Conclusão A utilização de baixas temperaturas no esporte tem um efeito benéfico na recuperação do desempenho esportivo durante pelo menos 24 horas após uma atividade física intensa (treino).

Antioxidant Activities of Vitamin C and Bi-carbonate Buffers on Hormones Secretion and Serum Metabolites of Heat-stressed Rabbit Buck

Aims: To evaluate the antioxidant activities of vitamin C and bicarbonate buffers on hormones secretion and serum metabolites of heat-stressed rabbit buck. Methodology: A total of twenty-five (25) Adult rabbit bucks (New Zealand White crosses) of 12 months old were used in this study. The rabbits were randomly allotted into the experimental treatments of five treatment groups with five (5) rabbits per treatment in a Completely Randomized Design (CRD). The treatment groups consisted of Control, Sodium Bicarbonate (Na2HCO3) and Potassium bicarbonate (KNO3), Vitamin C, and baobab fruit pulp meal (BFPM) as supplements respectively. The experiment lasted for 9 weeks. Temperature humidity of the pen house and thermoregulatory condition of the rabbits were evaluated. Blood samples (5 ml) were collected from the ear vein at 10.00 h from four rabbits chosen randomly from each group of rabbits respectively before and the end of the experiment for serum metabolite, thyroxine and testosterone hormones evaluation. Results: It was found that Vitamin C and BFPM significantly (P<0.05) reduced thermoregulatory parameters and increased hormonal secretions. The pattern of secretion of serum metabolites was not significantly (P<0.05) consistent. Conclusion: It was concluded that Vitamin antioxidants were more effective to ameliorate heat stress than bicarbonate buffers

Effect of Aging on Thermoregulatory and Cardiovascular Changes during Bathing in the Elderly / 日本温泉気候物理医学会雑誌

  Background: Aging affects thermoregulation and can potentially cause cardiovascular changes during bathing in the elderly, possibly leading to accidents and, in worst cases, drowning. However, adequate data on this subject are lacking. Therefore, the purpose of this study was to clarify the effect of aging on thermoregulatory and cardiovascular changes during bathing in the older versus younger adults the relationship between body temperature and thermoregulatory and cardiovascular changes.   Methods: Ten young (mean age: 20.4 years) and 10 elderly (mean age: 69.7 years) participants were asked to bathe for 15 min using water at 41°C. Tympanic temperature (Tty), skin blood flow (SkBF), sweating rate (SR), blood pressure, heart rate (HR), and double product (DP) were measured. In addition, we measured subjective psychological changes during bathing. Results: The results showed significant changes in SkBF, SR, and HR in the young participants rather than in the elderly participants. However, in the elderly participants, significant change was noted in systolic blood pressure (SBP).   Conclusion: These results demonstrate changes in thermal adaptation and SBP owing to structural and functional progression due to aging.

Investigation of factors affecting the rate of changes in endurance exercise performance by pre-cooling with ice slurry / 体力科学

To investigate the factors affecting the rate of improvement in endurance exercise performance following pre-cooling with ice slurry, we focused on individual physical characteristics and thermoregulatory capacity. Twenty-four healthy adults (12 males and 12 females) ingested 7.5g kg-1 of either ice slurry at -1°C (ICE) or control water at 20°C (CON) before cycling at 55% VO2max and continued cycling until the rectal temperature reached 38.5°C or untill exhaustion in a hot environment (controlled at 38°C, 40% relative humidity). The relationship between the rate of improvement in exercise performance and physical characteristics and thermoregulatory factors (changes in rectal temperature, the rate of rectal temperature increase, whole body sweat loss, mean metabolic heat production, and heat storage) was investigated. No correlation was noted between the rate of improvement in exercise performance and physical characteristics and heat storage. On the other hand, the rate of improvement in exercise performance showed significant correlations with changes in rectal temperature (r = -0.497), the rate of rectal temperature increases during exercise (r = -0.784), whole body sweat loss (r = 0.407), and mean metabolic heat production (r = -0.436). The rate of inhibition of sweating and the rate of increase in metabolic heat production by ice slurry ingestion during exercise have been suggested to be related to the rate of improvement in exercise performance. On the other hand, there was no relationship between body composition or VO2max and the rate of improvement in exercise performance.

Effect of Aging on Thermoregulatory and Cardiovascular Changes during Bathing in the Elderly / 日本温泉気候物理医学会雑誌

  Background: Aging affects thermoregulation and can potentially cause cardiovascular changes during bathing in the elderly, possibly leading to accidents and, in worst cases, drowning. However, adequate data on this subject are lacking. Therefore, the purpose of this study was to clarify the effect of aging on thermoregulatory and cardiovascular changes during bathing in the older versus younger adults the relationship between body temperature and thermoregulatory and cardiovascular changes.   　Methods: Ten young (mean age: 20.4 years) and 10 elderly (mean age: 69.7 years) participants were asked to bathe for 15 min using water at 41°C. Tympanic temperature (Tty), skin blood flow (SkBF), sweating rate (SR), blood pressure, heart rate (HR), and double product (DP) were measured. In addition, we measured subjective psychological changes during bathing. Results: The results showed significant changes in SkBF, SR, and HR in the young participants rather than in the elderly participants. However, in the elderly participants, significant change was noted in systolic blood pressure (SBP).   　Conclusion: These results demonstrate changes in thermal adaptation and SBP owing to structural and functional progression due to aging.

Effects of nasal breathing on partial pressure of carbon dioxide in arterial blood during prolonged exercise in a hot environment / 体力科学

Prolonged exercise in a hot environment increases the minute ventilation (VE) and respiratory rate (RR) with an increase in core temperature. This hyperthermia-induced hyperventilation decreases the partial pressure of arterial blood carbon dioxide (PaCO2). Conversely, nasal breathing during exercise has been reported to produce low VE and RR values and high PaCO2 values; however, no studies have investigated this in hot environments. Therefore, the purpose of this study was to clarify the effect of nasal breathing on estimated partial pressure of carbon dioxide in arterial blood (PaCO2,estimate) during prolonged exercise in a hot environment. Twelve university endurance athletes participated in the study and performed a 40-minutes steady-state cycling exercise at an intensity of 55% of peak oxygen uptake in a hot environment (room temperature 35℃, relative humidity 40%). Using randomized crossover design, two experiments were performed—nasal breathing condition (NB) and mouth breathing condition (MB). Moreover, physiological indices were measured during the exercise. Rectal temperature increased in both conditions, but there was no significant difference between these conditions. PaCO2,estimate values were significantly higher in NB between 10 minutes and 40 minutes of exercise (p < 0.05) compared to MB, and decreased with time in MB. Compared to MB, the VE was significantly lower in NB between 30 minutes and 40 minutes (p < 0.05), while the RR was significantly lower in NB between 25 minutes and 40 minutes of exercise (p < 0.05). Therefore, nasal breathing during a prolonged moderate-intensity exercise in a hot environment prevented the decrease in PaCO2,estimate due to hyperthermia-induced hyperventilation.

Incidencia de hipotermia perioperatoria inadvertida, en perros sometidos a anestesia general inhalatoria / Incidence of inadvertent perioperatory hypothermia, in dogs submitted to inhalation general anesthesia

RESUMEN La incidencia de hipotermia perioperatoria inadvertida es una de las principales complicaciones perianestésicas en caninos. El objetivo del presente estudio fue evaluar la incidencia de hipotermia perioperatoria inadvertida en 49 perros sometidos a anestesia general inhalatoria. Al finalizar el periodo preanestésico, transanestésico y postanestésico, se registró la temperatura corporal, de acuerdo con los siguientes rangos: hipertermia (>39,5°C), normotermia (38,5-39,5°C), hipotermia leve (38,4-36,5°C), hipotermia moderada (36,4-34,0°C), hipotermia severa (<34°C). En preanestesia, el 65% de los animales mostraron hipotermia leve y 2% hipotermia moderada. En transanestesia, 55% de los animales tuvieron hipotermia leve, 37% hipotermia moderada y 6,1% hipotermia severa. En postanestesia, 59% de los animales tuvieron hipotermia leve, 29% hipotermia moderada y 6% hipotermia severa. Se encontraron diferencias al comparar la temperatura basal, con la final transanestésica y postanestésica, respectivamente (p<0,001); del mismo modo, se obtuvieron diferencias al comparar la temperatura inicial, con la final del periodo transanestésico (p<0,001). Por otra parte, no hubo relación estadística entre las diferentes clasificaciones ASA, los procedimientos realizados, el sexo y los rangos etarios evaluados, así como tampoco hubo diferencia en el tiempo de extubación frente al tipo de procedimiento realizado. Los resultados de este estudio sugieren que, bajo las condiciones aquí planteadas, la incidencia de hipotermia preanestésica es mínima, mientras la aparición de hipotermia transanestésica y postanestésica de carácter leve, moderada y severa es mayor.

ABSTRACT The incidence of inadvertent perioperative hypothermia is one of the main perianesthetic complications in canines. The objective of the present study was to evaluate the incidence of inadvertent perioperative hypothermia in 49 dogs undergoing inhalation general anesthesia. At the end of the pre-anesthetic, trans-anesthetic, and post-anesthetic periods, body temperature was recorded, according to the following ranges: hyperthermia (>39.5°C), normothermia (38.5-39.5°C), mild hypothermia (38,4-36.5°C), moderate hypothermia (36.4-34.0°C), severe hypothermia (<34°C). In pre-anesthesia, 65% of the animals showed mild hypothermia, and 2% moderate hypothermia. In transanesthesia, 55% of the animals had mild hypothermia, 37% moderate hypothermia, and 6% severe hypothermia. In post-anesthesia 59% of the animals had mild hypothermia, 29% moderate hypothermia, and 6% severe hypothermia. Differences were found when comparing the basal temperature with the final trans-anesthetic and post-anesthetic respectively (p<0.001); Similarly, differences were obtained when comparing the initial temperature with the end of the trans-anesthetic period (p<0.001). On the other hand, there was no statistical relationship between the different ASA classifications, the procedures performed, sex, and the evaluated age ranges; as well as there was no difference in the extubation time compared to the type of procedure performed. The results of this study suggest that, under the conditions outlined here, the incidence of pre-anesthetic hypothermia is minimal, while the appearance of mild, moderate, and severe trans-anesthetic and post-anesthetic hypothermia is higher.

Efeito da suplementação com óleo de avocado (Persea americana Mill) na temperatura superficial corpórea de equinos antes e após exercício em esteira / [Effect of supplementation with avocado oil (Persea americana Mill) on body surface temperature of horses before and after exercise on treadmill]

Oito equinos foram distribuídos em delineamento randomizado cruzado, sendo um grupo sem suplementação (GC) e outro grupo suplementado com óleo de avocado (GOAv) por um período de sete semanas. Ao fim da sexta semana, os animais foram submetidos a teste padrão de exercício progressivo (TPEP) e, após sete dias, a teste de baixa intensidade e longa duração (BILD). Após o primeiro ciclo, houve período de descanso "washout" de 30 dias para troca de grupos para o segundo ciclo, que seguiu o protocolo do primeiro. A termorregulação foi avaliada com base na temperatura retal e na temperatura superficial corpórea, obtidas por termografia, de 15 regiões de interesse. A temperatura retal e as imagens termográficas foram obtidas antes, um minuto e 15 minutos após o exercício. Não houve diferença entre os grupos GC e GOAv em nenhum momento. Os resultados obtidos neste estudo revelaram que a suplementação de 5% da matéria seca (MS) com óleo de avocado por seis e sete semanas não influenciou na termorregulação com base na temperatura superficial corpórea dos equinos submetidos ao teste padrão de exercício progressivo (TPEP) e ao exercício de baixa intensidade e longa duração (BILD), respectivamente.(AU)

Eight equines were distributed in a randomized crossover design, one control group (CG) without supplementation and another group supplemented (SG) with avocado oil for a period of six weeks. At the end of the sixth week, the animals were submitted to standard exercise test (SET) and after seven days to the low intensity test (LIT). After the first cycle, there was a 30-day washout rest period to exchange groups for the second cycle, which followed the protocol of the first one. Thermoregulation was evaluated based on rectal temperature and body surface temperature of 15 regions of interest obtained by thermography. Rectal temperature and thermographic images were obtained before, one minute and 15 minutes after exercise. There was no difference between the CG and SG at any time. The results obtained in this study revealed that the supplementation of 5% of dry matter with avocado oil for six and seven weeks did not influence the thermoregulation based on the body surface temperature of the horses submitted to SET and LIT, respectively.(AU)

Thermoregulatory and perceptual responses of lean and obese fit and unfit girls exercising in the heat / Respostas termorregulatórias e perceptivas de meninas magras e obesas com alta e baixa aptidão aeróbica exercitando-se no calor

Abstract Objective: To verify the thermoregulatory and perceptual responses of obese and lean girls, either fit or unfit, exercising in the heat at a similar rate of metabolic heat production per unit body mass. Methods: A total of 34 pubescent girls were allocated in four groups: 12 obese fit, 9 obese unfit, 5 lean fit, and 8 lean unfit. The obese groups (13.2 ± 1.4 years, 40.5% ± 5.8% fat by DXA) differed in their aerobic fitness (V˙O2peak 76.0 ± 8.1 vs. 56.6 ± 5.8 mL.kg muscle mass-1.min-1), as well as the lean groups (13.1 ± 1.6 years, 24.0% ± 4.8% fat) (V˙O2peak 74.5 ± 2.9 vs. 56.2 ± 5.0 mL.kg muscle mass-1 min-1). Girls cycled two bouts of 25 min with a 10 min rest in between, at ∼5.4 W.kg-1 in the heat (36 °C and 40% relative humidity) and they were kept euhydrated. Rectal and skin temperatures and heart rate were measured every 5 min. Perceptual responses were evaluated throughout the exercise. Results: Initial rectal temperature was higher in the obese subjects compared to the lean subjects (37.5 ± 0.3 and 37.2 ± 0.3 °C). No difference was observed among the girls whom were obese (eight fit or unfit) and lean (also fit or unfit) throughout the exercise in rectal temperature (37.6 ± 0.2, 37.5 ± 0.3, 37.5 ± 0.3, 37.4 ± 0.3 °C, respectively), skin temperature (34.8 ± 0.8, 35.1 ± 1.0, 34.4 ± 0.9, 35.2 ± 0.9 °C), and heart rate (128 ± 18; 118 ± 12, 130 ± 16, 119 ± 16 beats min-1). No differences were observed in perceptual responses among groups. Conclusion: Regardless of the adiposity or aerobic fitness, pubescent girls had similar thermoregulatory and perceptual responses while cycling in the heat at similar metabolic heat production.

Resumo Objetivo: Verificar as respostas termorregulatórias e perceptivas de meninas obesas e magras, com alta e baixa aptidão aeróbica, exercitando-se no calor com produção metabólica de calor similar por massa corporal. Métodos: Um total de 34 meninas púberes foram alocadas em quatro grupos: 12 obesas com alta aptidão aeróbica, 9 obesas com baixa aptidão aeróbica, 5 magras com alta aptidão aeróbica e 8 magras com baixa aptidão aeróbica. Os grupos obesos (13,2 ± 1,4 anos, 40,5% ± 5,8% de gordura por DXA) diferiram em sua aptidão aeróbica (V˙O2peak 76,0 ± 8,1 vs. 56,6 ± 5,8 mL.kg de massa muscular-1.min-1), bem como os grupos magros (13,1 ± 1,6 anos, 24,0% ± 4,8% de gordura) (V˙O2peak 74,5 ± 2,9 vs. 56,2 ± 5,0 mL.kg de massa muscular-1min-1). As meninas pedalaram duas sessões de 25 minutos com descanso de 10 minutos entre as sessões, a ∼5,4 W.kg-1 no calor (36∘C e 40% de umidade relativa) e foram mantidas hidratadas. As temperaturas retal e cutânea e a frequência cardíaca foram medidas a cada 5 minutos. As respostas perceptivas foram avaliadas durante o exercício. Resultados: A temperatura retal inicial foi maior nas meninas obesas em comparação com as magras (37,5 ± 0,3 e 37,2 ± 0,3 °C). Não houve diferença entre as meninas obesas (com alta aptidão aeróbica ou não) e magras (também com alta aptidão aeróbica ou não) durante todo o exercício em relação à temperatura retal (37,6 ± 0,2; 37,5 ± 0,3; 37,5 ± 0,3; 37,4 ± 0,3 °C; respectivamente), temperatura da pele (34,8 ± 0,8; 35,1 ± 1,0; 34,4 ± 0,9; 35,2 ± 0,9 °C), e frequência cardíaca (128 ± 18; 118 ± 12, 130 ± 16, 119 ± 16 batimentos.min-1). Não foram observadas diferenças nas respostas perceptivas entre os grupos. Conclusão: Independentemente da adiposidade ou do condicionamento aeróbico, as meninas púberes tiveram respostas termorregulatórias e perceptivas semelhantes, enquanto pedalavam no calor com uma produção metabólica de calor similar.

Trabajos originales Preferencia termal de machos adultos de Cryphiops caementarius previamente aclimatados a diferen- tes temperaturas / Thermal preference of adult males of Cryphiops caementarius previously acclimated at different temperatures

Resumen El objetivo fue determinar la preferencia termal de machos adultos de Cryphiops caementarius previamente aclimatados a diferentes temperaturas. Los camarones se colectaron del río Pativilca. En laboratorio, los camarones se aclimataron durante 30 días en nueve acuarios, cada uno con 10 recipientes circulares. En cada recipiente hubo un camarón (10 por acuario). Las temperaturas de aclimatación fueron de 19, 24 y 28 °C. El sistema de gradiente de temperatura (12 a 33 °C) fue una canaleta de PVC (3 m de longitud y 10 cm de profundidad) con 18 compartimentos. En un extremo de la canaleta se colocaron termorreguladores sumergibles (100W) y en el otro extremo, bolsas con hidrogel congeladas. La preferencia termal se determinó por el método agudo y las pruebas se realizaron entre las 08:00 y 14:00 h. Los camarones aclimatados a 24 °C se desplazaron a compartimentos cuyas temperaturas fueron más altas que la temperatura de aclimatación. Los camarones aclimatados a 24 °C se desplazaron a compartimentos cuyas temperaturas fueron alrededor de la temperatura de aclimatación. Los camarones aclimatados a 28 °C se desplazaron a compartimentos donde las temperaturas fueron más bajas que aquella de aclimatación. La preferencia termal de los camarones aclimatados a 19 °C fue de 22.7 °C, y la de los aclimatados a 24 °C fue de 24.8 °C, ambos sin diferencias significativas (p>0.05). En cambio, en los aclimatados a 28°C fue de 21.1 °C, que solo difirió (p<0.05) con los aclimatados a 19 °C. La preferencia termal final fue de 24.5 °C.

Abstract In this work, we establish the thermal preference of Cryphiops caementarius adult males, previously acclimated at different temperatures. Shrimp were collected from the Pativilca River. In the laboratory, shrimp were acclimated for 30 days in nine aquariums, each with 10 circular containers. In each container, there was a shrimp (10 per aquarium). Acclimation temperatures were 19, 24 and 28 °C. The gradient temperature system (12 to 33 °C) consisted for a PVC gutter (3 m long and 10 cm deep) with 18 compartments. Submersible thermoregulators (100W) were placed at one end of the gutter and the other end, frozen hydrogel bags. The thermal preference was determined by the acute method and the tests were performed between 08:00 and 14:00 h. Shrimp acclimated at 24 °C moved to compartments whose temperatures were higher than the acclimation temperature. Shrimp acclimated at 24 °C moved to compartments whose temperatures were around the acclimation temperature. Shrimp acclimated at 28 °C moved to compartments where temperatures were lower than acclimation. The thermal preference of acclimated shrimp at 19 °C was 22.7 °C, and those acclimated at 24 °C were 24.8 °C, both without significant differences (p>0.05). On the other hand, in acclimated ones at 28 °C it was 21.1 °C, which only differed (p<0.05) with those acclimated at 19 °C. The final thermal preference was 24.5 °C.

Limitations of temporal (forehead) temperature readings as a screening method for Covid-19 / Limitaciones de la lectura de la Temperatura temporal (en la frente) como método de tamizaje para el COVID-19

Abstract As the Covid-19 pandemic continues to evolve, many countries are in the process of reopening schools, churches, and businesses. In an effort to screen for potentially infected individuals, temporal artery (forehead) temperature is measured in thousands of people each day. This editorial discusses some of the major limitations of this procedure as a screening method for Covid-19 and warns against the danger of the false sense of security that this practice may cause.

Resumen Conforme continúa la evolución de la pandemia por Covid-19, muchos países inician el proceso de reapertura de escuelas, iglesias y negocios. En un esfuerzo de tamizaje para detectar personas potencialmente infectadas, cada día se les está midiendo la temperatura de la arteria temporal (en la frente) a miles de personas. En este editorial se plantean algunas de las limitaciones principales de este procedimiento como método de tamizaje para Covid-19 y se advierte acerca del peligro de caer en una falsa sensación de seguridad, causada por esa práctica.

Resumo Com o avanço contínuo da pandemia de Covid-19, muitos países estão em processo de reabertura de escolas, igrejas e empresas. Em um esforço para rastrear indivíduos potencialmente infectados, a temperatura da artéria temporal (testa) é medida em milhares de pessoas todos os dias. Este editorial discute algumas das principais limitações deste procedimento como método de triagem para o Covid-19 e alerta contra o perigo da falsa sensação de segurança que essa prática pode causar.

Análise termográfica aplicada na produção de calor corporal de vacas F1 HxZ manejadas em diferentes microclimas / Thermographic analysis applied to body heat production of F1 HxZ cows managed in different microclimates

Avaliou-se a produção de calor corporal de vacas F1 HxZ manejadas em diferentes microclimas. Foram avaliadas 48 vacas, divididas em três grupos, manejadas em pastos e microclimas diferentes. Cada grupo foi subdividido em três grupos de suplementação fornecida durante a ordenha. Os registros termográficos dos flancos direito e esquerdo ocorreram com os animais a pasto. As temperaturas do olho e retal foram mensuradas após a ordenha. O ITGU caracterizou sinal de perigo para o microclima 1 no período da tarde (81,7) e para o microclima 2 nos turnos da manhã e da tarde (81,6 e 83,8, respectivamente). No microclima 2, houve diferença da temperatura do flanco direito para animais do grupo 2 em relação aos animais do grupo 3. A temperatura do flanco esquerdo foi superior para os animais do grupo 1. O microclima 1 foi caracterizado de conforto térmico, e o 2 de desconforto nos períodos da manhã e da tarde. A suplementação não influenciou na produção de calor dos animais. As médias da temperatura retal e do olho não diferiram entre os grupos, e a correlação apresentou valores baixos e moderados para os microclimas 1 e 2, respectivamente. A oferta de diferentes fontes de suplementação não interfere na produção de calor corporal de vacas F1 HxZ, mesmo quando fornecido em ambiente climático em que o ITGU é próximo a 84.(AU)

Body heat production of F1 HxZ cows managed in different microclimates was evaluated. We evaluated 48 cows, divided into two groups, managed in different pastures and microclimates. Each group was subdivided into three groups of supplementation provided during milking. The thermographic records of the right and left flanks occurred with the animals on the grass. Eye and rectal temperatures were measured after milking. The BGT had a danger signal for microclimate 1 in the afternoon (81.7) and microclimate 2 in the morning and afternoon shifts (81.6 and 83.8, respectively). In microclimate 2, there was difference in the temperature of the right flank for animals in group 2 in relation to the animals in group 3. The temperature of the left flank was higher for the animals in the group 1. Microclimate 1 was characterized by thermal comfort and 2 was discomfort in the morning and afternoon. Supplementation did not influence the heat production of the animals. Rectal and eye mean averages did not differ between groups and the correlation presented low and moderate values for microclimate 1 and 2, respectively. The supply of different sources of supplementation does not interfere with the production and body heat of F1 HxZ cows even when supplied in a climatic environment in which the BGT is close to 84.(AU)

Computer Simulation of Individualized Human Thermal Response during General Anesthesia / 医用生物力学

Objective To analyze the effects of anesthesia-induced thermoregulatory system impairment and low temperature environment of the operating room on the perioperative thermoregulation of individualized patients by constructing a computer simulation model. Methods A simple anesthesia model was proposed and then incorporated into the self-developed individualized thermoregulatory model, in which human body was represented as a cylinder with two layers of the core and the skin. The integrated model could be used to assess the effects of individualized characteristics such as age, obesity, and cardiovascular diseases on thermoregulation by modifying different physiological parameters involving sweating, shivering and cutaneous vasomotion. Simulation of the general anesthesia effects on human thermoregulation could be achieved by reducing basal metabolic rate and thresholds for vasoconstriction and shivering. Results The elderly people showed lower core temperature but higher skin temperature, compared with the young people. In a low temperature environment, an increase in fat thickness or an increase in severity degree of the left ventricular failure (LVF) might alleviate the decrease in core temperature, while an increase in wind speed or relative humidity could result in a decrease in core temperature. When the threshold setting of vasoconstriction was reduced by 0-5-3 ℃, the core temperature showed a significant decrease. Conclusions By comparing model simulations with experimental measurements, the reliability and validity of the model in predicting human transient thermal responses during varying external thermal environment was verified. The individualized characteristics of human body had an important influence on human body temperature in a low temperature environment. Moreover, the combination of individualized characteristics of human body and general anesthesia further complicated the body′s thermoregulation and posed significant challenges for clinicians.

Cuidados de enfermagem na termorregulação de recém-nascidos prematuros: revisão integrativa / Cuidados de enfermería en la termorregulación de recién nacidos prematuros: revisión integradora / Nursing care in the thermo-regulation of preterm newborns: an integrative review

RESUMO Objetivo: evidenciar e discutir os cuidados de enfermagem no que concerne à termorregulação de recém-nascidos prematuros. Método: revisão integrativa com busca por artigos primários completos, publicados de 2014 a 2019, em português, inglês ou espanhol na Biblioteca Virtual de Saúde, PubMed e Cochrane Library. Utilizou-se os descritores: Termorregulação; Recém-Nascido; Enfermagem; "Enfermeiras e Enfermeiros"; "Body Temperature Regulation"; e "Infant, Newborn". Resultados: foram incluídos nove artigos para síntese, com estudos realizados em diferentes países. Emergiram categorias sobre cuidados na termorregulação de recém-nascidos prematuros e sobre protocolos para a termorregulação neonatal na prática clínica. Considerações finais: os cuidados de enfermagem na termorregulação incluem o uso de cama aquecida, aquecedor radiante, métodos de isolamento corporal e ajuste da temperatura ambiente. Este estudo contribui fornecendo base para pesquisas sobre a situação clínica de recém-nascidos e possíveis associações entre a assistência de enfermagem que poderiam comprometer a termorregulação neonatal.

RESUMEN: Objetivo: evidenciar y debatir los cuidados de enfermería en lo referente a la termorregulación de recién nacidos prematuros. Método: revisión integradora con búsqueda por artículos primarios completos, publicados entre 2014 y 2019, en portugués, inglés o español en la Biblioteca Virtual de Salud, PubMed y la Cochrane Library. Se utilizaron los siguientes descriptores: Termorregulação; Recém-Nascido; Enfermagem; "Enfermeiras e Enfermeiros"; "Body Temperature Regulation"; e "Infant, Newborn". Resultados: se incluyeron nueve artículos para la síntesis, con estudios realizados en diferentes países. Surgieron categorías sobre cuidados en la termorregulación de recién nacidos prematuros y sobre protocolos para la termorregulación neonatal en la práctica clínica. Consideraciones finales: los cuidados de enfermería en la termorregulación incluyen el uso de una cama con calefacción, calefactor radiante, métodos de aislamiento corporal y ajuste de la temperatura ambiente. Este estudio contribuye con el aporte de una base para realizar investigaciones sobre la situación clínica de los recién nacidos y sus posibles asociaciones en la asistencia de enfermería que podrían poner en riesgo la termorregulación neonatal.

ABSTRACT Objective: to evidence and discuss nursing care regarding thermo-regulation for pre-term newborns. Method: An integrative review with search by complete primary articles, published from 2014 to 2019 in Portuguese, English or Spanish in the Virtual Health Library, PubMed, and the Cochrane Library. The following descriptors were used: Termorregulação; Recém-Nascido; Enfermagem; "Enfermeiras e Enfermeiros"; "Body Temperature Regulation"; and "Infant, Newborn". Results: nine articles were included for synthesis, with studies conducted in different countries. Categories emerged about care in the thermo-regulation of pre-term newborns and on protocols for neonatal thermo-regulation in the clinical practice. Final considerations: nursing care in thermo-regulation includes the use of a heated bed, radiant heater, body insulation methods, and adjustment of room temperature. This study contributes by providing a basis for research on the clinical situation of newborns and possible associations in nursing care that could compromise neonatal thermo-regulation.

Termorregulación de la lagartija Liolaemus chacoensis (Squamata: Liolaemidae) durante su ciclo reproductivo, en el Chaco occidental, Argentina

La regulación de la temperatura corporal en las lagartijas juega un rol clave para la supervivencia de las especies. Su condición fisiológica, en referencia a su dependencia de la temperatura ambiente, los convierte en un excelente modelo de estudio. Asimismo, los cambios en el ciclo reproductivo provocan modificaciones en los parámetros termofisiológicos. Este estudio es el primero en abordar la relación de la termorregulación con la actividad reproductiva y el sexo, para una especie de Liolaemus de la ecorregión del Chaco. El objetivo de este trabajo fue determinar cómo influye el período reproductivo, de reclutamiento y el pos-reproductivo, así como también el efecto del sexo y la longitud-hocico-cloaca sobre la termorregulación de Liolaemus chacoensis. Los individuos fueron capturados a mano en el sector Sur de Valle Fértil, provincia de San Juan, Argentina. Se capturaron un total de 44 individuos durante noviembre 2014, febrero 2015 y marzo 2015. Se registró la temperatura corporal (Tc), la temperatura del sustrato (Ts) y del aire (Ta). También, se utilizaron modelos biofísicos para registrar la temperatura operativa. Posteriormente, en el laboratorio se evaluó la temperatura seleccionada (Tsel). Luego se calculó el índice de eficiencia termorregulatoria. Los resultados indicaron que la Tc de L. chacoensis se relacionó positivamente con la Ta, presentando un comportamiento heliotérmico que se mantuvo durante los períodos y el sexo. Asimismo, la Tc fue mayor para el período reproductivo y de reclutamiento con respecto al pos-reproductivo. En particular, solo el sexo tuvo efecto sobre la Tsel, sin embargo para el rango intercuartil de Tsel tuvo efecto tanto el período del ciclo reproductivo como el sexo. El índice de eficiencia termorregulatoria indicó que L. chacoensis es un termoconforme absoluto. Sin embargo, en el período reproductivo tanto machos como hembras cambian hacia la termorregulación activa. Estos resultados muestran que los parámetros termofisiológicos, varían en los diferentes períodos del ciclo reproductivo y la selección activa de micrositios sería un mecanismo para el mantenimiento de la temperatura corporal de la especie.

Thermoregulation of Liolaemus chacoensis lizard (Squamata: Liolaemidae) during its reproductive cycle, in the Western Chaco, Argentina. Regulation of body temperature in lizards plays a key role in the survival of species. Their physiological condition, in reference to their dependence on the ambient temperature makes them an excellent study model. Also, changes in the reproductive cycle cause changes in thermophysiological parameters. This study is the first to address the relationship of thermoregulation with reproductive activity and sex, for a species of Liolaemus from the Chaco ecoregion. The aim of this work was to determine how the reproductive, recruitment and post-reproductive periods influences, as well as the effect of sex and snout-vent length on the thermoregulation of Liolaemus chacoensis. Individuals were captured by hand in the Southern sector of Valle Fertil, San Juan province, Argentina. A total of 44 individuals were captured during the months of November 2014, February 2015 and March 2015. Body (Tb), substrate (Ts) and air (Ta) temperatures were recorded. Also, biophysical models were used to record operative temperatures. Later selected temperatures (Tsel) were evaluated at the laboratory. Finally, thermoregulatory efficiency index was calculated. Results indicated that L. chacoensis Tb was positively related to Ta, presenting a heliothermic behavior that was maintained during periods and sex. Also, Tb was higher in reproductive and recruitment periods than in post-reproductive period. In particular, only sex had an effect on Tsel, however for the interquartile range of Tsel both the period of reproductive cycle and sex had an effect. The thermoregulatory efficiency index indicated that L. chacoensis is an absolute thermoconformist. However, in the reproductive period both males and females change towards active thermoregulation. These results show that thermophysiological parameters vary in different periods of reproductive cycle and the active microsite selection would be a mechanism in maintenance of body temperature of this species.

Use of infrared thermography in Quarter Horse submitted to team roping / Uso da termografia infravermelha em equinos da raça Quarto de Milha submetidos à prova de laço em dupla

This study aimed to verify whether the body and local temperatures change after high-intensity, short-duration exercise (team roping) and whether different pieces of training influence these changes. To this end, twelve animals, males and females, aged 3-6 years, with an average weight of 450 kg, were used. The horses were divided into two groups: regular training (RTG) and sporadic training (STG). The surface temperatures were assessed using a specific thermal camera. Temperatures of the ocular, thoracolumbar, distal tendon (thoracic and pelvic limbs) and croup regions were measured 30 min before, immediately after, and one, two, six and 24 hours after competition simulation. In the RTG, there was an increase in surface eye temperature two hours after exercise, returning to baseline level 24 hours later. In the STG, increase in eye temperature occurred immediately after exercise and returned to baseline level two hours later. Temperature of the pelvic limb tendons and croup (right side) rose immediately after exercise and did not return to baseline level 24 hours later. Team roping exercise increased the surface temperature of the distolateral thoracic and pelvic limb, croup and thoracolumbar regions in both groups and the eye temperature in the STG. Training frequency influenced the surface temperature profile in the distolateral pelvic limb, croup and thoracolumbar regions.(AU)

Os objetivos do presente estudo foram verificar se as temperaturas corpóreas e locais se alteram após exercício de alta intensidade e curta duração (prova de laço em dupla) e se treinamentos distintos podem influenciar nestas alterações. Foram utilizados 12 animais, machos e fêmeas, com idade entre 3 e 6 anos e peso médio de 450kg. Os animais foram divididos em dois grupos: treino regular (GTR) e treino esporádico (GTE). As aferições da temperatura por meio de termografia infravermelha foram feitas por uma câmera termal específica. As medições das temperaturas das regiões ocular, toracolombar, tendíneas distais (membros torácicos e pélvicos) e garupa foram realizadas 30 minutos antes, imediatamente depois, uma, duas, seis e 24 horas após a simulação de competição. No GTR houve aumento de temperatura ocular duas horas após o exercício, retornando ao basal apenas 24 horas depois. No GTE o aumento ocorreu imediatamente após o exercício e retornando ao basal duas horas depois. As temperaturas da região dos tendões dos membros pélvicos e garupa (lado direito) elevaram-se imediatamente após o exercício e não retornaram ao basal após 24 horas. O exercício de laço em dupla aumentou as temperaturas superficiais nas regiões distolateral de membros torácicos e pélvicos, garupa e região toracolombar de ambos os grupos e da temperatura ocular do GTE. A frequência de treinamento influenciou o perfil de temperatura superficial na região distal de membros pélvicos, garupa e toracolombar.(AU)

Los antagonistas fisiológicos de los pirógenos endógenos y su papel en la fiebre / The physiological antagonists of endogenous pyrogens and their role in fever

La fiebre es una reacción fisiológica de defensa que involucra múltiples componentes celulares y humorales en íntimo equilibrio homeostático. Ante la presencia de microorganismos exógenos o sustancias potencialmente patógenas se instaura una respuesta febril nativa, regulada principalmente por el hipotálamo que involucra la producción y secreción de sustancias proinflamatorias y mediadores febrigénicos, con una cascada de acontecimientos que elevan la temperatura corporal. La fiebre normalmente es una respuesta controlada, la temperatura corporal suele elevarse a niveles tolerables para los tejidos. En situaciones patológicas esta acción reactiva de defensa puede resultar lesiva a nivel celular, pero, el organismo posee mecanismos endógenos protectores que usualmente suelen ser biológicamente suficientes para regular la intensidad de la respuesta febril. Esta modulación térmica que protege al cuerpo de los efectos colaterales de la fiebre es mediada por criógenos endógenos; sustancias con la capacidad de disminuir la temperatura corporal y en casos específicos producir hipotermia protectora.

Fever is a physiological reaction that involves multiple cellular and humoral components in intimate homeostatic balance. This reaction takes place in the presence of exogenous microorganisms or potentially pathogenic substances regulated mainly by the hypothalamus that involves the production and secretion of proinflammatory substances and febrigenic mediators, which determines a cascade of events that raise the body temperature. The fever is usually a controlled response, body temperature usually rises to tolerable levels for tissues. In most cases a controlled feverish reaction that unravels to tolerable tissue levels is deployed. In pathological situations this reaction can be harmful to cells, however, the organism possesses endogenous defense mechanisms that usually regulate the intensity of the fever response. This thermal modulation that protects the body from the side effects of fever is mediated by endogenous cryogens; substances with the ability to lower body temperature and in specific cases produce protective hypothermia.

Selección de hábitat y composición de la dieta de Microlophus occipitalis (Reptilia: Tropiduridae) en Sechura, Piura - Perú / Habitat selection and diet composition of Microlophus occipitalis (Reptilia: Tropiduridae) in Sechura, Piura - Peru

Microlophus occipitalis es una lagartija diurna que se distribuye en las costas de Ecuador y Perú, de la cual se pretende determinar el uso y selección de los recursos de hábitat, así como los principales componentes de su dieta. Se trabajó en la laguna Ñapique (Piura, Perú), usando el Diseño Tipo I de Manly (la disponibilidad y uso se estiman para todos los individuos de la especie dentro del área de estudio), y el Coeficiente de Selección de Manly para determinar la selección de recursos. La composición de la dieta y amplitud del nicho trófico se analizó con el índice de Levins estandarizado. Un total de 1055 observaciones permitieron determinar que M. occipitalis seleccionó los recursos Tronco y Piedra. La actividad dominante fue la Alimentación, seguida del Soleamiento. Existió un alto consumo de Himenópteros, seguido de los Coleópteros. Microlophus occipitalis es una especie que usa principalmente los troncos y las piedras que se presentan en su hábitat para poder termorregular. Su principal actividad es la alimenticia. Es una especie carnívora que en la temporada de primavera-verano consume principalmente hormigas y coleópteros pero complementa su dieta con flores y hojas en baja cantidad, en un consumo aparentemente accidental.

Microlophus occipitalis is a diurnal lizard distributed on the coasts of Ecuador and Peru, of which it is tried to determine the use and resources selection of habitat, as well as the main components of its diet. Survey was done in Napique lagoon (Piura, Peru), using the Design Type I of Manly (availability and use are estimated for all individuals of the species within the study area), and the Manly Selection Ratio to determine resources selection. The composition of the diet and amplitude of the trophic niche was analyzed with the standardized Levins index. A total of 1055 observations allowed determining that M. occipitalis selected the Trunk and Stone resources. The dominant activity was Food, followed by Sunbathe. There was a high consumption of Hymenoptera, followed by the Coleoptera. Microlophus occipitalis is a species that mainly uses the trunks and stones that occur in its habitat to be able to thermoregulate. Its main activity is food. It is a carnivorous species that in the spring-summer season consumes mainly ants and coleoptera but complements its diet with flowers and leaves in low quantity, in a seemingly accidental consumption.

Effect of stocking rate and floor types on performance, skin temperature and leukogram in pigs raising / Efecto de la carga animal y el tipo de piso sobre el rendimiento, la temperatura de la piel y leucograma en la cría de cerdos

ABSTRACT Objective. The aim of this study was to evaluate the performance, thermoregulatory characteristics and the leukogram of growing finishing pigs reared in different stocking rates kept on compact floor pens or with shallow pool pens. Material and methods. Thirty-six pigs were used in two steps (total of 72 animals were used). In the first step it was analysed performance pig (daily feed intake, weight gain and feed: gain ratio) and backfat thickness (P2). In the second step, the same analyzes were repeated, in addition, analysis of leukogram and skin temperature was performed in P2 and anal region, at the end of growing and finishing phase. Results. It was evaluated for differences between treatments and stocking. It was not found effect of floor type on growing phase, but the use of shallow pool had a negative effect on the gain and feed: gain ratio in the finishing phase, as well as lower surface temperature in the anal region on treatment with shallow pool in the finishing phase. No effect of treatments and type of floor on pig leukogram. Allowing more space/animal decreased backfat thickness. The use of shallow pool affected negatively the performance in the finishing phase. Conclusions. The shallow pool uses impair the finishing pig performance, despite improving thermolysis, with no effect observed on cell immune response.

RESUMEN Objetivo. El objetivo de este estudio fue evaluar el rendimiento, las características de termorregulación, y el leucograma de cerdos de engorde, criados en diferentes densidad mantenidos en corrales de piso compactos o corrales con lámina de agua. Material y métodos. Treinta y seis cerdos se utilizaron en dos etapas (un total de 72 animales utilizados). En el primer paso, se analizaron las características zootécnicas (consumo diario de alimento, ganancia de peso y la conversión alimenticia) y el espesor de grasa dorsal (P2). En el segundo paso, los mismos análisis se repitieron, además, el análisis de leucograma y temperatura de la piel se realizó en P2 y la región anal, al final de la recría y terminación. Resultados. Se evaluaron las diferencias entre los tratamientos. No se encontró efecto del tipo de corrales en fase de recría, pero el uso de los corrales con lámina de agua tuvo un efecto negativo sobre la ganancia y conversión alimenticia en la fase de terminación, así como una menor temperatura de la superficie en la región anal en el tratamiento con lámina de agua en la fase de terminación. No hubo efecto de los tratamientos y tipo de corales sobre el Leucograma de los cerdos. Permitiendo más espacio/animal disminuyó el espesor de grasa dorsal. El uso de la lámina de agua afectó negativamente al rendimiento en la fase de terminación. Conclusiones. El uso de lámina de agua afectó el rendimiento de los cerdos de terminación, a pesar de la mejora de termólisis, sin efecto visible en la respuesta inmune celular.