scholarly journals Thermal Stress Indices in Young Nellore Bulls Raised in Tropical Environments

2019 ◽  
Vol 47 (1) ◽  
Author(s):  
Andressa Alves Storti ◽  
Maria Regina Bueno De Mattos Nascimento ◽  
Carina Ubirajara De Faria ◽  
Natascha Almeida Marques da Silva

Background: Thermal stress indices are important in predicting and choosing means for mitigating heat stress and defining critical environmental conditions for animal welfare and performance. The aim of this study was to determine the association between 16 thermal stress indices and thermophysiological variables in young Nellore bulls raised in a tropical pasture to determine the most effective parameter of heat stress to assist in the management of the thermal environment and animal welfare.Materials, Methods & Results: Seventy-eight young Nellore bulls (Bos taurus indicus), with a mean age of 10.5 months and mean body weight of 242.09 ± 32.17 kg at first collection, and 17.92 months and body weight 335.80 ± 39.02 kg at last collection, were used. During the experimental period, rectal temperature (RT) and surface temperature at the forehead, scapula, and groin, from which the average surface temperature (AST) was calculated, were measured. The difference between the AST and air temperature (i.e., AST – AT) and between the RT and AST (i.e., RT – AST) defined the thermal gradient. For the evaluation of thermal environment, the dry bulb, wet bulb, and globe temperatures, and wind speed were measured. Relative humidity, mean radiant temperature, solar radiation, temperature humidity index (THI), black global temperature humidity index (BGHI), equivalent temperature index (ETI), environmental stress index (ESI), respiratory rate predictor (PRR), heat load index (HLI), comprehensive climate index (CCI), and index of thermal stress for cows (ITSC) were calculated. The average and maximum air temperatures were above thermal comfort levels, while the average relative humidity was within the ideal limit for cattle. The average globe temperature was higher than the air temperature. Solar radiation presented very high values and wind speeds were very low. RT indicated normothermia in the cattle, and AST and thermal gradient (i.e., AST – AT) indicated thermal comfort. The 16 thermal stress indices demonstrated a significant positive and moderate correlation with AST, but were not significantly correlated with RT.Discussion: The average (28.14°C) and maximum (31.90°C) air temperatures indicated discomfort, since the ideal temperature for cattle is ≤ 27°C. The high thermal load of this region can contribute to poor animal welfare, thus requiring the provision of natural or artificial shade for pasture farming. The cattle in this study were in thermal equilibrium given that they maintained RT within the normal range, and the maximum limit was higher. If RT is maintained within physiological limits, the mechanisms of thermoregulation are able to eliminate excess heat (i.e., thermolysis is equivalent to thermogenesis). The AST was 5.4°C below the RT. It is important to note that deep body temperature (i.e., RT) is more stable than the surface body temperature, which is influenced by ambient temperature. Considering that there was no correlation between thermal stress indices and RT, and that the cattle were able to maintain RT within physiological limits, the Nellore bulls in this study were adapted to the environment. The thermal stress indices evaluated in this study adequately reflected heat stress in young Nellore bulls raised in pastures in a tropical environment. Surface temperature was the physiological parameter that responded most significantly to environmental conditions.

Buildings ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 22 ◽  
Author(s):  
Ayaz Hosham ◽  
Tetsu Kubota

The purpose of this study was to investigate the effects of building microclimate on the indoor thermal environment of traditional Japanese houses, focusing especially on the shading effect of trees as well as the cooling effect of spraying water. Basically, the indoor thermal environment was found to follow the outdoor conditions due to the open-plan and lightweight wooden structure. Nevertheless, air temperatures of the living rooms in the two case study houses were lower than the corresponding outdoors by approximately 0.5 °C and 2 °C, respectively. It was found that the semi-outdoor spaces acted as thermal buffers for promoting cross-ventilation as well as pre-cooling to provide “warm but breezy” conditions to the surrounding indoor spaces. The results showed that the surface temperature of semi-outdoor spaces can be reduced by shading and water spraying, among which shading has prolonged effects and water spraying can reduce the surface temperature during peak hours and the following night.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Hanna Leona Lokys ◽  
Jürgen Junk ◽  
Andreas Krein

Projected climate change will cause increasing air temperatures affecting human thermal comfort. In the highly populated areas of Western-Central Europe a large population will be exposed to these changes. In particular Luxembourg—with its dense population and the large cross-border commuter flows—is vulnerable to changing thermal stress. Based on climate change projections we assessed the impact of climate change on human thermal comfort over the next century using two common human-biometeorological indices, the Physiological Equivalent Temperature and the Universal Thermal Climate Index. To account for uncertainties, we used a multimodel ensemble of 12 transient simulations (1971–2098) with a spatial resolution of 25 km. In addition, the regional differences were analysed by a single regional climate model run with a spatial resolution of 1.3 km. For the future, trends in air temperature, vapour pressure, and both human-biometeorological indices could be determined. Cold stress levels will decrease significantly in the near future up to 2050, while the increase in heat stress turns statistically significant in the far future up to 2100. This results in a temporarily reduced overall thermal stress level but further increasing air temperatures will shift the thermal comfort towards heat stress.


2020 ◽  
Vol 30 (1) ◽  
pp. 25
Author(s):  
Fitra Aji Pamungkas ◽  
B P Purwanto ◽  
W Manalu ◽  
A Yani ◽  
R G Sianturi

Assessment on reproduction physiological parameters of ruminant caused by thermal stress usually uses invasive methods. However, these methods are less accurate because they are subjective, require a significant time and resources, and there are problems in animal welfare. Infrared thermography is one alternative solution that can be used. Infrared thermography is a modern, non-invasive, non-destructive, and safe technique to visualize thermal profile and surface temperature. This paper describes the application of infrared thermography in monitoring reproduction physiology status of ruminant. This method does not require physical contact and allows direct visualisation of temperature distribution so that it can be used as a reference in understanding and evaluating several parameters in livestock.


Author(s):  
Е.О. КРУПИН

В различные синоптические сроки выявлено количество измерений по индексу температуры и влажности (ТВИ) в животноводческом помещении, при которых у коров наблюдается тепловой стресс. Спрогнозированы данные о температуре тела и частоте дыхания коров в условиях теплового стресса и его отсутствия, в том числе и по четырем срокам измерений. Определен потенциально возможный уровень молочной продуктивности коров при отсутствии теплового стресса. По методу E.C. Thom установлено, в среднем, 80,0% значений ТВИ, характеризующих условия среды как «тепловой стресс». Наблюдалось увеличение доли данных значений с 10 ч утра до 19 ч. По A. Berman et al. Выявлено, в среднем, 10,9% значений ТВИ, а по M.K. Yousef — 5,0%, относящихся к тепловому стрессу. В 15-й синоптический срок измерений по Гринвичу в животноводческом помещении спрогнозирована наибольшая вероятность теплового стресса. Среднее увеличение температуры тела коров с 6-го по 15-й синоптические сроки измерений при тепловом стрессе составит 1,0% (0,4°C, P<0,001), а частоты дыхания — 51,3% (18 дыхательных движений в 1 мин, (P<0,001). Максимальная динамика увеличения температуры тела наблюдается в 13 ч и 16 ч, а частоты дыхания — в 13 ч. Потенциальная молочная продуктивность дойных коров в летние месяцы может быть в среднем на 8,9% выше. In various synoptic terms in the cowshed room, the amount of measurements of the temperature of the heat and humidity index was revealed when the cows suffer from thermal stress. Data on body temperature and respiration rate of cows in conditions of heat stress and its absence were predicted, including those for four measurement periods. Potentially possible level of milk production of cows in the absence of heat stress was determined. According to E.C. Thom is found on average 80.0% of the values of THI, characterizing environmental conditions as "heat stress". An increase in the share of these values is observed in the period from 10:00 to 19:00. According to A. Berman et al. revealed on average 10.9% of THI values, and according to M.K. Yousef — 5.0% of the THI values related to heat stress. In 15, the synoptic term of measurements in Greenwich in the cowshed, the highest probability of heat stress is predicted. The average increase in body temperature of cows from 6 to 15 synoptic term of measurements in Greenwich heat stress will be 1.0% (0.4°C, P<0.001), and the respiration rate will be 51.3% (18 respiratory movements per minute, P<0.001). The maximum dynamics of an increase in body temperature is observed at 13:00 and 16:00 for body temperature, and respiratory rate at 13:00. The potential milk production of dairy cows in the summer months can be 8.9% higher on average.


2020 ◽  
Vol 172 ◽  
pp. 24009
Author(s):  
Jing Ren ◽  
Ming fang Tang

Window gardens are known to provide a window view with psychological and physiological benefits, whether they can be used for passive cooling of buildings remains to be investigated. This paper aims to supplement the impact of window gardens on the thermal performance of windows, walls, and even indoor air temperatures, which previous research has ignored. A field experiment was conducted for two classrooms with integrated planting troughs outside the windows, with and without living plants. The indoor air temperature and the interior surface temperature of the two classrooms were measured on a typical hot summer day, with windows closed and air conditioners switched off. The results show that: Window garden with living plants can not only reduce the average temperature of the indoor air by 1.1 ℃, but also reduce the average temperature of the interior surface of the building envelope by 2.8 ℃, the reduction of interior surface temperature is more obvious, which is due to the formation of a cold bridge. Therefore, Window garden can improve the summer indoor thermal environment in hot summer and warm winter area in China.


Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1657
Author(s):  
Maria Alice Junqueira Gouvêa Silva ◽  
Patrícia Ferreira Ponciano Ferraz ◽  
Luana Mendes dos Santos ◽  
Gabriel Araújo e Silva Ferraz ◽  
Giuseppe Rossi ◽  
...  

The objective of this study was to characterize and evaluate the temperature and humidity index (THI) of New Zealand white (NZW) rabbits kept in a rabbit house using geostatistical techniques. Furthermore, we sought to evaluate its relationship with respiratory frequency (RF) and ear surface temperature (EST). The experiment was conducted at the Federal University of Lavras, Brazil. A total of 52 NZW rabbits were used. For the characterization of the thermal environment, the dry bulb temperature (tdb, °C), relative humidity (RH, %), and dew point temperature (tdp, °C) were collected at 48 points in the rabbit house at 6:00 a.m., 12:00 p.m., and 6:00 p.m. for seven days. The RF and EST of the animals was monitored. Subsequently, the THI was calculated and the data were analyzed using geostatistical tools and kriging interpolation. In addition, the RF and EST data were superimposed on the rabbit house’s THI data maps. The magnitude of the variability and structure of the THI inside the rabbit house were characterized and the heterogeneity was visualized. Critical THI points inside the rabbit house and in locations where animals with high RF and ESTs were housed were identified, thus providing information about improving the production environment.


2021 ◽  
Author(s):  
Alexander Hoffman ◽  
Leslie Dees ◽  
Haruka Wada

Abstract Populations without a sufficient rate of genetic adaptation may risk extinction in the face of rapid environmental change, however, phenotypic plasticity can facilitate their persistence. For example, mothers can prepare offspring for the thermal environment young will experience through transgenerational plasticity. In oviparous species, whether mothers can prepare offspring to cope with thermal stress experienced as embryos is largely unknown. We demonstrate that when zebra finch mothers are exposed to a heat stress, their offspring show altered heart rates as embryos in response to high incubation temperatures, as well as an increase in eggshell pore density that was positively correlated with survival. These results are the first to show that temperature induced transgenerational plasticity may promote embryonic survival in an oviparous species.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Shin Akatsuka ◽  
Tadashi Uno ◽  
Masahiro Horiuchi

In recent years, the risk of heat disorder in daily life has increased dramatically because the thermal environment has been deteriorating. The main objective of this study was to examine regional differences in the relationship between heat disorder incidence rate and heat stress indices at Yamanashi Prefecture, Japan. Daily maximum air temperature and daily maximum WBGT were used as heat stress indices in each region. Nonlinear regression analysis was used to examine the regional difference in the relationship between the heat disorder incidence rate and heat stress indices in each region. The heat disorder incidence rate was correlated with both indices of heat stress in all regions. However, the more appropriate heat stress index for heat disorder prevention differed among regions. The distributions of heat stress indices, such as the slope of regression curve and the temperature threshold, differed in each region, irrespective of the index used. Therefore, the criteria for thermal conditions for heat disorder prevention need to be determined for each region, considering the regional characteristics of the relationship between the heat disorder incidence rate and heat stress indices.


1965 ◽  
Vol 64 (1) ◽  
pp. 37-49 ◽  
Author(s):  
J. L. Clapperton ◽  
J. P. Joyce ◽  
K. L. Blaxter

Interest in the gain of heat by farm animals exposed to sunshine has largely been confined to countries in which air temperatures are high and in which exposure of stock to sunshine leads to their distress. Riemerschmidt's (1943) studies indicated the considerable magnitude of the heat gained by oxen standing in the sun in South Africa, and studies by MacFarlane, Morris & Howard (1956) in Australia showed that with sheep standing in the sun the wool surface temperature could rise to 85° C. These studies of MacFarlane have been confirmed in Egypt by Eyal (1963), and were subject to a theoretical analysis by Priestley (1957). Such observations, together with earlier ones reviewed by Findlay (1958), show that in many equatorial regions solar radiation is a major factor accounting for heat stress in farm ruminants.


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