scholarly journals Análise do conforto térmico para trabalhadores rurais durante a colheita do tabaco na região do Vale do Rio Pardo

2020 ◽  
Vol 42 ◽  
pp. 4
Author(s):  
Heloísa De Gois ◽  
Zanandra Boff de Oliveira ◽  
Clarissa Moraes da Silva ◽  
Irajá Jantasch de Souza ◽  
Larrissa Ribeiro Rodrigues ◽  
...  

Tobacco cultivation, besides being an important source of income for family farming, also translates into one of the most relevant in the state. Thus, the aim of the present study is to analyze the thermal comfort of rural workers during tobacco harvest, through the temperature and humidity index (UTI) calculated with meteorological data from the years 2017/2018 and 2018/2019, in the Vale region. from Rio Pardo. For this, information was first collected anonymously through a questionnaire answered by 80 rural producers from different municipalities in the region and later, a bioclimatic analysis was performed through the calculation and interpretation of the UTI. The results indicated that the tobacco harvest in the region is held from October to January, in the morning (07:00 to 11:00) and afternoon (14:00 to 19:00) shifts. Thermal comfort analysis showed that in the morning there is no heat stress (UTI <74), unlike the afternoon where UTI indicates thermal heat discomfort (from November to January), which is progressive over the period. (UTI increases from 2:00 pm to 6:00 pm) and may be potentiated by the physical stress accumulated throughout the working day.

Atmosphere ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 1013
Author(s):  
Max Anjos ◽  
António Lopes ◽  
Andrews José de Lucena ◽  
Francisco Mendonça

Characterizing the behaviour of the sea breeze phenomenon is the foremost factor in the reduction in the heat stress and the achievement of the pleasant environment in coastal cities globally. However, this seminal study shows that the Sea Breeze Front (SBF) development can be related to an increase in outdoor thermal discomfort in a northeastern Brazilian city during summer. We explored the relationship between SBF and thermal comfort conditions using in situ meteorological observations, the SBF identification method, local climate zones (LCZs) classification, and the Physiological Equivalent Temperature (PET) thermal comfort index. SBF days and Non-SBF days were characterized in terms of weather conditions, combining meteorological data and technical bulletins. SBF days included hot and sunny days associated with the centre of the Upper Tropospheric Cyclonic Vortices (UTCV). In contrast, Non-SBF days were observed in UTCV’s periphery because of cloudy sky and rainfall. The results showed that the mean temperature and PET in the SBF days were 2.0 °C and 3.8 °C higher, respectively, compared to Non-SBF days in all LCZ sites. The highest PET, of 40.0 °C, was found on SBF days. Our findings suggest that SBF development could be an aggravating factor for increasing heat stress of the people living in the northeastern coast of the Brazilian city, after SBF passage.


2013 ◽  
Vol 33 (1) ◽  
pp. 19-27 ◽  
Author(s):  
Eduardo A. de Almeida ◽  
Roberta Passini

The research was developed to evaluate the use of different types of roofing materials regularly used in poultry houses. Measurements of thermal comfort were made through the use of techniques such as the Black Globe and Humidity Index (BGHI), the Thermal Heat Load (THL) and Enthalpy (H). Conducted in the State University of Goiás, during the months of April and May, 2011, the experiment was composed of five different treatments: AC - Asbestos cement tiles, BA -Bamboo tiles, BAP - Bamboo tiles painted in white, FB -Vegetable fiber tiles and bitumen, FBP -Vegetable fiber tiles and bitumen painted in white. The experiment consisted in 15 repetitions, which were considered the different days of measurements taken. Throughout the studied period, the time of the day considered the least comfortable was the one observed at 2:00pm, and the coverage of vegetable fiber and bitumen showed the highest value of BGHI (84.1) when compared to other types of coverage, characterizing a situation of lower thermal comfort, and no difference was found for THL and H on treatments in the studied region.


Author(s):  
Kemal Yazgan

The objective of this study was to detect the relationship between weather information, obtained from nearest public weather station, and milk productions of Holstein cows breeding in Sanliurfa province of Turkey. Data used in this study comprised 711,968 first-five parity individual daily milk and live weight records of 939 Holstein cows. Results from this study indicated that using combination of minimum ambient temperature and relative humidity values one day earlier from daily milk yield in temperature – humidity index (THI) formula can be good alternative for determining heat stress in Holstein dairy cows under climatological conditions in Sanliurfa province of Turkey. As a result, this study confirmed that for quantifying heat stress in dairy cows valuable information can obtained from public weather stations.


Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 473 ◽  
Author(s):  
Xiaodong Du ◽  
Lenn Carpentier ◽  
Guanghui Teng ◽  
Mulin Liu ◽  
Chaoyuan Wang ◽  
...  

Heat stress is one of the most important environmental stressors facing poultry production and welfare worldwide. The detrimental effects of heat stress on poultry range from reduced growth and egg production to impaired health. Animal vocalisations are associated with different animal responses and can be used as useful indicators of the state of animal welfare. It is already known that specific chicken vocalisations such as alarm, squawk, and gakel calls are correlated with stressful events, and therefore, could be used as stress indicators in poultry monitoring systems. In this study, we focused on developing a hen vocalisation detection method based on machine learning to assess their thermal comfort condition. For extraction of the vocalisations, nine source-filter theory related temporal and spectral features were chosen, and a support vector machine (SVM) based classifier was developed. As a result, the classification performance of the optimal SVM model was 95.1 ± 4.3% (the sensitivity parameter) and 97.6 ± 1.9% (the precision parameter). Based on the developed algorithm, the study illustrated that a significant correlation existed between specific vocalisations (alarm and squawk call) and thermal comfort indices (temperature-humidity index, THI) (alarm-THI, R = −0.414, P = 0.01; squawk-THI, R = 0.594, P = 0.01). This work represents the first step towards the further development of technology to monitor flock vocalisations with the intent of providing producers an additional tool to help them actively manage the welfare of their flock.


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 722
Author(s):  
Jang-Hoon Jo ◽  
Jalil Ghassemi Nejad ◽  
Dong-Qiao Peng ◽  
Hye-Ran Kim ◽  
Sang-Ho Kim ◽  
...  

This study aims to characterize the influence of short-term heat stress (HS; 4 day) in early lactating Holstein dairy cows, in terms of triggering blood metabolomics and parameters, milk yield and composition, and milk microRNA expression. Eight cows (milk yield = 30 ± 1.5 kg/day, parity = 1.09 ± 0.05) were homogeneously housed in environmentally controlled chambers, assigned into two groups with respect to the temperature humidity index (THI) at two distinct levels: approximately ~71 (low-temperature, low-humidity; LTLH) and ~86 (high-temperature, high-humidity; HTHH). Average feed intake (FI) dropped about 10 kg in the HTHH group, compared with the LTLH group (p = 0.001), whereas water intake was only numerically higher (p = 0.183) in the HTHH group than in the LTLH group. Physiological parameters, including rectal temperature (p = 0.001) and heart rate (p = 0.038), were significantly higher in the HTHH group than in the LTLH group. Plasma cortisol and haptoglobin were higher (p < 0.05) in the HTHH group, compared to the LTLH group. Milk yield, milk fat yield, 3.5% fat-corrected milk (FCM), and energy-corrected milk (ECM) were lower (p < 0.05) in the HTHH group than in the LTLH group. Higher relative expression of milk miRNA-216 was observed in the HTHH group (p < 0.05). Valine, isoleucine, methionine, phenylalanine, tyrosine, tryptophan, lactic acid, 3-phenylpropionic acid, 1,5-anhydro-D-sorbitol, myo-inositol, and urea were decreased (p < 0.05). These results suggest that early lactating cows are more vulnerable to short-term (4 day) high THI levels—that is, HTHH conditions—compared with LTLH, considering the enormous negative effects observed in measured blood metabolomics and parameters, milk yield and compositions, and milk miRNA-216 expression.


2021 ◽  
Vol 13 (5) ◽  
pp. 2836
Author(s):  
Khawar Shahzad ◽  
Muhammad Sultan ◽  
Muhammad Bilal ◽  
Hadeed Ashraf ◽  
Muhammad Farooq ◽  
...  

Poultry are one of the most vulnerable species of its kind once the temperature-humidity nexus is explored. This is so because the broilers lack sweat glands as compared to humans and undergo panting process to mitigate their latent heat (moisture produced in the body) in the air. As a result, moisture production inside poultry house needs to be maintained to avoid any serious health and welfare complications. Several strategies such as compressor-based air-conditioning systems have been implemented worldwide to attenuate the heat stress in poultry, but these are not economical. Therefore, this study focuses on the development of low-cost and environmentally friendly improved evaporative cooling systems (DEC, IEC, MEC) from the viewpoint of heat stress in poultry houses. Thermodynamic analysis of these systems was carried out for the climatic conditions of Multan, Pakistan. The results appreciably controlled the environmental conditions which showed that for the months of April, May, and June, the decrease in temperature by direct evaporative cooling (DEC), indirect evaporative cooling (IEC), and Maisotsenko-Cycle evaporative cooling (MEC) systems is 7–10 °C, 5–6.5 °C, and 9.5–12 °C, respectively. In case of July, August, and September, the decrease in temperature by DEC, IEC, and MEC systems is 5.5–7 °C, 3.5–4.5 °C, and 7–7.5 °C, respectively. In addition, drop in temperature-humidity index (THI) values by DEC, IEC, and MEC is 3.5–9 °C, 3–7 °C, and 5.5–10 °C, respectively for all months. Optimum temperature and relative humidity conditions are determined for poultry birds and thereby, systems’ performance is thermodynamically evaluated for poultry farms from the viewpoint of THI, temperature-humidity-velocity index (THVI), and thermal exposure time (ET). From the analysis, it is concluded that MEC system performed relatively better than others due to its ability of dew-point cooling and achieved THI threshold limit with reasonable temperature and humidity indexes.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 339
Author(s):  
Musa Bah ◽  
Muhammad Afzal Rashid ◽  
Khalid Javed ◽  
Talat Naseer Pasha ◽  
Muhammad Qamer Shahid

Water buffaloes wallow in water to combat heat stress during summer. With the decreasing reservoirs for wallowing, the farmers use sprinklers to cool the buffaloes in Pakistan. These sprinklers use a large quantity of groundwater, which is becoming scarce. The objective of the current study was to determine the effect of different sprinkler flow rates on the physiological, behavioral, and production responses of Nili Ravi buffaloes during summer. Eighteen buffaloes were randomly subjected to three sprinkler flow rate treatments in a double replicated 3 × 3 Latin square design. The flow rates were 0.8, 1.25, and 2.0 L/min. During the study, the average afternoon temperature humidity index was 84.6. The 1.25 and 2.0 L/min groups had significantly lower rectal temperature and respiratory rates than the 0.8 L/min group. Water intake was significantly higher in the 0.8 L/min group. Daily milk yield was higher in the 1.25 and 2.0 L/min groups than in the 0.8 L/min group. These results suggested that the sprinkler flow rates > 0.8 L/min effectively cooled the buffaloes. The sprinkler flow rate of 1.25 L/min appeared to be more efficient, as it used 37.5% less water compared to the 2.0 L/min.


Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1062
Author(s):  
Michael Abera ◽  
Yesihak Yusuf Mummed ◽  
Mitiku Eshetu ◽  
Fabio Pilla ◽  
Zewdu Wondifraw

Fogera cattle are among indigenous breeds of cattle in the northern part of Ethiopia. However, their response to heat stress (HS) under different seasonal variations has not been well investigated. This study was aimed to determine physiological, hematological, biochemical, and growth parameters of Fogera cattle calves to HS during dry season, short rainy, and long rainy. A total of 72 calves (24 for each season) that were 6 months of age with an equal number of males and females were evaluated for physiological, hematological, biochemical, and growth parameters. Daily ambient temperature (AT) and relative humidity (RH) were recorded two times per day during the study periods from which the daily average temperature–humidity index (THI) was calculated. The study revealed higher AT and THI during dry and short seasons while higher RH was observed during the long rainy season. Physiological parameters except rectal temperature were affected by the seasons. Hematological parameters were also affected by season except for packed cell volume. Biochemical and growth parameters were also significantly affected by the seasons. THI was positively related with physiological but negatively with growth parameters. Thus, the THI value of 66 can be considered as optimum for high weight gain and normal physiological response to HS in Fogera cattle calves under their current production system.


Author(s):  
Pooja Devi ◽  
Mahendra Singh ◽  
Yallappa M. Somagond ◽  
A.K. Roy

Background: Heat stress causes oxidative stress and declines milk production potential of cows. The physiological responses and skin temperature of heat stressed animals are good indices for deterring the heat stress. The efficacy of medicinal herb Chlorophytum borivilianum (CB) was tested in lowering the rise in values of physiological responses and skin temperature in crossbred vis a vis Indigenous cows. Methods: Eighteen Tharparkar (TP) and Crossbred KF cows in mid-lactation were given; No supplement (control), a low (T1, n=6) and a high dose (T2, n=6) of CB @ 40 and 80 mg/kg BW/day, respectively for 90 days during hot-humid season. Respiration rate (RR), pulse rate (PR), rectal temperature (RT) and skin temperature (ST) was recorded at the site of forehead, neck, rear body, and udder surface in the morning and afternoon at weekly intervals. Temperature-humidity index (THI) was calculated to assess the degree of thermal stress in animals. Result: Physiological responses and skin temperatures were higher (p less than 0.01) in the afternoon than morning intervals in TP and KF cows. CB feeding significantly lowered physiological responses and ST (p less than 0.01) in high dose as compared to low dose. It was concluded that CB feeding @ 80 mg/kg BW/day effectively alleviates the heat stress. Indigenous cows were found more heat tolerant in comparison to crossbred cows.


Author(s):  
Valquiria Cordeiro da Silva ◽  
Robson de Sousa Nascimento ◽  
José Pinheiro Lopes Neto ◽  
Fernanda Fernandes de Melo Lopes ◽  
Jaciara Ribeiro Miranda ◽  
...  

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