scholarly journals Modeling of Heat Stress in Sows—Part 1: Establishment of the Prediction Model for the Equivalent Temperature Index of the Sows

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1472
Author(s):  
Mengbing Cao ◽  
Chao Zong ◽  
Xiaoshuai Wang ◽  
Guanghui Teng ◽  
Yanrong Zhuang ◽  
...  
Keyword(s):  
Heat Stress ◽  
Relative Humidity ◽  
Skin Temperature ◽  
Air Temperature ◽  
Physiological Response ◽  
Equivalent Temperature ◽  
Air Velocity ◽  
Thermal Indices ◽  
Thermal Index ◽  
Temperature Index

Heat stress affects the estrus time and conception rate of sows. Compared with other life stages of pigs, sows are more susceptible to heat stress because of their increased heat production. Various indicators can be found in the literature assessing the level of heat stress in pigs. However, none of them is specific to assess the sows’ thermal condition. Moreover, thermal indices are mainly developed by considering partial environment parameters, and there is no interaction between the index and the animal’s physiological response. Therefore, this study aims to develop a thermal index specified for sows, called equivalent temperature index for sows (ETIS), which includes parameters of air temperature, relative humidity and air velocity. Based on the heat transfer characteristics of sows, multiple regression analysis is used to combine air temperature, relative humidity and air velocity. Environmental data are used as independent variables, and physiological parameters are used as dependent variables. In 1029 sets of data, 70% of the data is used as the training set, and 30% of the data is used as the test set to create and develop a new thermal index. According to the correlation equation between ETIS and temperature-humidity index (THI), combined with the threshold of THI, ETIS was divided into thresholds. The results show that the ETIS heat stress threshold is classified as follows: suitable temperature ETIS < 33.1 °C, mild temperature 33.1 °C ≤ ETIS < 34.5 °C, moderate stress temperature 34.5 °C ≤ ETIS < 35.9 °C, and severe temperature ETIS ≥ 35.9 °C. The ETIS model can predict the sows’ physiological response in a good manner. The correlation coefficients R of skin temperature was 0.82. Compared to early developed thermal indices, ETIS has the best predictive effect on skin temperature. This index could be a useful tool for assessing the thermal environment to ensure thermal comfort for sows.

scholarly journals Modeling of Heat Stress in Sows Part 2: Comparison of Various Thermal Comfort Indices

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1498
Author(s):  
Mengbing Cao ◽  
Chao Zong ◽  
Yanrong Zhuang ◽  
Guanghui Teng ◽  
Shengnan Zhou ◽  
...  
Keyword(s):  
Heat Stress ◽  
Thermal Environment ◽  
Production Performance ◽  
Heat Index ◽  
Growth Stages ◽  
Equivalent Temperature ◽  
Thermal Indices ◽  
Important Indicator ◽  
Thermal Index ◽  
Heat Indices

Heat stress has an adverse effect on the production performance of sows, and causes a large economic loss every year. The thermal environment index is an important indicator for evaluating the level of heat stress in animals. Many thermal indices have been used to analyze the environment of the pig house, including temperature and humidity index (THI), effective temperature (ET), equivalent temperature index of sows (ETIS), and enthalpy (H), among others. Different heat indices have different characteristics, and it is necessary to analyze and compare the characteristics of heat indices to select a relatively suitable heat index for specific application. This article reviews the thermal environment indices used in the process of sow breeding, and compares various heat indices in four ways: (1) Holding the value of the thermal index constant and analyzing the equivalent temperature changes caused by the relative humidity. (2) Analyzing the variations of ET and ETIS caused by changes in air velocity. (3) Conducting a comparative analysis of a variety of isothermal lines fitted to the psychrometric chart. (4) Analyzing the distributions of various heat index values inside the sow barn and the correlation between various heat indices and sow heat dissipation with the use of computational fluid dynamics (CFD) technology. The results show that the ETIS performs better than other thermal indices in the analysis of sows’ thermal environment, followed by THI2, THI4, and THI7. Different pigs have different heat transfer characteristics and different adaptability to the environment. Therefore, based on the above results, the following suggestions have been given: The thermal index thresholds need to be divided based on the adaptability of pigs to the environment at different growth stages and the different climates in different regions. An appropriate threshold for a thermal index can provide a theoretical basis for the environmental control of the pig house.

The influence of local temperature and air velocity changes on the thermal sensations of users' working in surgical clothing

2021 ◽  
pp. 1420326X2199081
Author(s):  
Magdalena Młynarczyk ◽  
Anna Bogdan ◽  
Tomasz Jankowski
Keyword(s):  
Air Temperature ◽  
Surgical Procedures ◽  
Thermal Conditions ◽  
Thermal Manikin ◽  
Medical Team ◽  
Accurate Assessment ◽  
Equivalent Temperature ◽  
Air Velocity ◽  
Temperature Index ◽  
Velocity Changes

Thermal conditions in operating rooms are mainly dictated by the need to meet the safety/comfort requirements of the patient. However, the accuracy of performed surgical procedures depends on the surgeon and others members of medical team. Hence, their comfort sensation should be also factored in. The study sought to find out how thermal sensations of people working in surgical clothing can be modified through a local change in air velocity and temperature around the user. A series of tests was carried out with a thermal manikin to make an accurate assessment of the effectiveness of this type of equipment. The tests included changes of the ambient temperature, supply air temperature and air velocity. The operational efficiency was assessed on the basis of the equivalent temperature index ( teq). Results show that the final result of teq was mostly determined by air velocity rather than the supply air temperature.

scholarly journals Evaluation of Thermal Indices as the Indicators of Heat Stress in Dairy Cows in a Temperate Climate

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2459
Author(s):  
Geqi Yan ◽  
Hao Li ◽  
Zhengxiang Shi
Keyword(s):  
Heat Stress ◽  
Dairy Cows ◽  
Systematic Evaluation ◽  
Temperate Climate ◽  
Climate Index ◽  
Future Research ◽  
Equivalent Temperature ◽  
Thermal Indices ◽  
Actual Performance ◽  
Temperature Index

Many thermal indices (TIs) have been developed to quantify the severity of heat stress in dairy cows. Systematic evaluation of the representative TIs is still lacking, which may cause potential misapplication. The objectives of this study were to evaluate the theoretical and actual performance of the TIs in a temperate climate. The data were collected in freestall barns at a commercial dairy farm. The heat transfer characteristics of the TIs were examined by equivalent air temperature change (ΔTeq). One-way ANOVA and correlation were used to test the relationships between the TIs and the animal-based indicators (i.e., rectal temperature (RT), respiration rate (RR), skin temperature (ST), and eye temperature (ET)). Results showed that the warming effect of the increased relative humidity and the chilling effect of the increased wind speed was the most reflected by the equivalent temperature index (ETI) and the comprehensive climate index (CCI), respectively. Only the equivalent temperature index for cows (ETIC) reflected that warming effect of solar radiation could obviously increase with increasing Ta. The THI and ETIC showed expected relationships with the RT and RR, whereas the CCI and ETIC showed expected relationships with the ST and ET. Moreover, CCI showed a higher correlation with RT (r = 0.672, p < 0.01), ST(r = 0.845, p < 0.01), and ET (r = 0.617, p < 0.01) than other TIs (p < 0.0001). ETIC showed the highest correlation with RR (r = 0.850, p < 0.01). These findings demonstrated that the CCI could be the most promising thermal index to assess heat stress for housed dairy cows. Future research is still needed to develop new TIs tp precisely assess the microclimates in cow buildings.

Analysis of Comfort Indices and Their Impact on the Environment

2020 ◽  
Vol 71 (2) ◽  
pp. 161-166
Author(s):  
Carmen Otilia Rusanescu ◽  
Marin Rusanescu ◽  
Mihaela Begea ◽  
Elena Valentina Stoian
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Weather Station ◽  
Equivalent Temperature ◽  
Thermal Discomfort ◽  
Temperature Index ◽  
Discomfort Index ◽  
Comfort Indices

In this paper, the following comfort indices and their implication on the environment are analyzed: the effective equivalent temperature index (TEE), the humidity temperature index (UTI) and the Thom discomfort index (DI Thom). These indices highlight the comfort or thermal discomfort of a region depending on the values for the air temperature, the relative humidity of the air during the period 2009-2018 recorded by the weather station AWWS/EV from the Faculty of Engineering of Biotechnical Systems, Politehnica University of Bucharest.

Thermal Lethality of Salmonella in Chicken Leg Quarters Processed via an Air/Steam Impingement Oven

2004 ◽  
Vol 67 (3) ◽  
pp. 493-498 ◽  
Author(s):  
R. Y. MURPHY ◽  
K. H. DRISCOLL ◽  
L. K. DUNCAN ◽  
T. OSAILI ◽  
J. A. MARCY
Keyword(s):  
Relative Humidity ◽  
Surface Area ◽  
Air Temperature ◽  
Cooking Time ◽  
Air Velocity ◽  
Poultry Products ◽  
Product Surface ◽  
Cooking Times

Chicken leg quarters were injected with 0.1 ml of the cocktail culture per cm2 of the product surface area to contain about 7 log(CFU/g) of Salmonella. The inoculated leg quarters were processed in an air/steam impingement oven at an air temperature of 232°C, an air velocity of 1.4 m/s, and a relative humidity of 43%. The endpoint product temperatures were correlated with the cooking times. A model was developed for pathogen thermal lethality up to 7 log(CFU/g) reductions of Salmonella in correlation to the product mass (140 to 540 g) and cooking time (5 to 35 min). The results from this study are useful for validating thermal lethality of pathogens in poultry products that are cooked via impingement ovens.

scholarly journals A Study on Suitable Habitat for Swiftlet Farming

2009 ◽  
Vol 1 (1) ◽  
pp. 1-7
Author(s):  
Ibrahim S. H. ◽  
Teo W.C. ◽  
Baharun A.
Keyword(s):  
Relative Humidity ◽  
Light Intensity ◽  
Air Temperature ◽  
Capital Investment ◽  
Suitable Habitat ◽  
Key Factors ◽  
Air Velocity ◽  
Animal Products ◽  
New Industry ◽  
Temperature Surface

Swiftlet farming is a new industry in Sarawak as compared to other long-standing industries such as rubber, palm oil and timber. It is one of the businesses that involved a small capital investment that could generate enormous returns in the future. Swiftlet farming involves the conversion of human-centric building into structures for Swiftlet. The purpose of this conversion is to let Swiftlet for nesting and protect them. The design and construction of such building will also helps to accommodate Swiftlets' population. The nest of the Edible-nest Swiftlet rank amongst the world's most expensive animal products. Therefore, in order to increase the productivity of bird nest, study of the suitable habitat for Swiftlet should be done thoroughly. Environmental factors such as air temperature, surface temperature, relative humidity, air velocity and light intensity are the key factors for a successful Swiftlet farm house. Internal air temperature of building should be maintained from 26°C to 35°C, relative humidity from 80% to 90%, low air velocity and light intensity less than 5 LUX. Proper ventilation and installation of a humidifier could help the building to achieve the desirable range of environment factors. Location of structure will also be considered from direct sunlight direction to reduce the internal temperature. Only licensed Swiftlet farming is legal.

scholarly journals Comparison of Thermal Comfort between Sapporo and Tokyo—The Case of the Olympics 2020

Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 444
Author(s):  
Yuting Wu ◽  
Kathrin Graw ◽  
Andreas Matzarakis
Keyword(s):  
Heat Stress ◽  
Thermal Comfort ◽  
Olympic Games ◽  
Physiologically Equivalent Temperature ◽  
Precipitation Rate ◽  
Equivalent Temperature ◽  
Thermal Indices ◽  
Climate Conditions ◽  
Northern City ◽  
The Olympic Games

Weather and climate conditions can be decisive regarding travel plans or outdoor events, especially for sport events. The Olympic Games 2020, postponed to 2021, will take place in Tokyo at a time which is considered to be the hottest and most humid time of the year. However, a part of the athletic competitions is relocated to the northern city Sapporo. Therefore, it is important to quantify thermal comfort for different occasions and destinations and make the results accessible to visitors and sport attendees. The following analysis will quantify and compare thermal comfort and heat stress between Sapporo and Tokyo using thermal indices like the Physiologically Equivalent Temperature and the modified Physiologically Equivalent Temperature (PET and mPET). The results reveal different precipitation patterns for the cities. While a higher precipitation rate appears in Sapporo during winter, the precipitation rate is higher in Tokyo during summer. PET and mPET exhibit a greater probability of heat stress conditions in Tokyo during the Olympic Games, whereas Sapporo has more moderate values for the same period. The Climate-Tourism/Transfer-Information-Scheme (CTIS) integrates and simplifies climate information and makes them comprehensible for non-specialists. The CTIS of Tokyo illustrates lower suitable conditions for “Heat stress”, “Sunny days” and “Sultriness”. Transferring parts of the athletics competition to a northern city is thus more convenient for athletes, staff members and spectators. Hence, heat stress can be avoided and an acceptable outdoor stay is ensured. Overall, this quantification and comparison of the thermal conditions in Sapporo and Tokyo reveal limitations but also possibilities for the organizers of the Olympic Games. Furthermore it can be used to raise awareness for promoting or arranging countermeasures and heat mitigation at specific events and destinations, if necessary.

Drying of Heavily Salted Fish

1945 ◽  
Vol 6d (5) ◽  
pp. 380-391 ◽  
Author(s):  
E. P. Linton ◽  
A. L. Wood
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Skin Surface ◽  
Medium Size ◽  
Air Velocity ◽  
Salted Fish

The experimental drying of cut samples and of whole salt fish under various air conditions shows that the optimum air velocity is 100 to 125 cm. per second, air temperature 26 °C, and relative humidity 45 to 55 per cent. High drying potentials inhibit drying owing to the formation of an impervious salt-protein crust on the surface of the fish.The skin surface of the fish dries about 50 to 75 per cent as fast as the split surface. Under the recommended air conditions medium size salt codfish are dried from 130 per cent to 75 per cent, dry basis, moisture in about 40 hours.

scholarly journals Human-biometeorological assessment of Kharkiv (Ukraine) in the summer season

2021 ◽  
Vol 54/55 (54/55) ◽  
pp. 43-54
Author(s):  
Olga Shevchenko ◽  
Sergiy Snizhko ◽  
Mariia Matviienko
Keyword(s):  
Heat Stress ◽  
Heat Waves ◽  
Average Frequency ◽  
Summer Season ◽  
Equivalent Temperature ◽  
Thermal Index ◽  
Heat Adaptation ◽  
The City ◽  
Rayman Model ◽  
Recreation And Tourism

The objective of this research is to assess the bioclimate of the city of Kharkiv in the summer season using the human thermal index of physiologically equivalent temperature (PET). The RayMan model has been used to obtain PET values. The results suggest that most days in Kharkiv during the summer are characterized by heat stress of various intensity 65.7% in June, 84.6% in July, 77.1% in August. The average frequency of comfortable weather is very low, varying from 12.6 to 25%. During heat waves, the frequency of days in Kharkiv with heat stress increases significantly, amounting to 96.3%. The results of the Kharkiv bioclimate assessment using PET may be used to create measures for heat adaptation and develop infrastructure for recreation and tourism in the city during hot periods.

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