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Arq. bras. med. vet. zootec. (Online) ; 73(6): 1361-1370, Nov.-Dec. 2021. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1355674


The replacement of bedding in compost dairy barns (CB) comprises a recurrent management practice, but bedding materials are often not readily available in all regions and the choice of alternative materials is necessary. The objective was to evaluate the thermal attributes of carnauba straw (CS) bedding in compost dairy barn facilities. Environmental monitoring operations were performed at a commercial farm located in Northeast Brazil. Mini weather stations were used to evaluate environmental variables. The THI was evaluated as one of the comfort parameters. Analysis of the spatial distribution of bed surface temperature (BST) in the CB was performed using geostatistical techniques. The cows remained out of the comfort zone according to THI results. The BST indicated satisfactory performance and from the thermal point of view can be used as alternative bedding material in CB facilities. However, it was observed that the CS showed fast biomass degradation compared to conventional materials, widely known. In addition, inadequate temperature values (< 45°C) were found in the deeper of the CS bed, signaling higher risks of pathogenic microbial activity. Additional studies are needed for searching the proper management plans that increase the life span of the bed formed by carnauba straw.(AU)

A reposição de cama na instalação Compost Barn (CB) compreende uma prática recorrente de manejo, porém os materiais de cama muitas vezes não estão facilmente disponíveis em todas as regiões, sendo necessária a adoção de materiais alternativos. Objetivou-se avaliar os atributos térmicos da cama à base de bagana de carnaúba (BC) para instalações CB. Foram realizadas operações de monitoramento ambiental em uma fazenda comercial situada no nordeste do Brasil. Miniestações meteorológicas foram utilizadas para avaliação de variáveis ambientais. O ITU foi avaliado como um dos parâmetros de conforto. A distribuição espacial da temperatura superficial da cama (TSC) no galpão foi analisada usando técnicas da geoestatística. As vacas mantiveram-se fora da zona de conforto, conforme resultados do ITU. A TSC indicou desempenho satisfatório e, do ponto de vista térmico, pode ser utilizada como material alternativo para cama em instalações CB. Entretanto, observou-se que a BC apresentou rápida degradação da biomassa em comparação a materiais convencionais, amplamente conhecidos. Além disso, valores inadequados de temperatura (< 45°C) foram encontrados nas camadas profundas da cama de BC, sinalizando maiores riscos de atividade microbiana patogênica. Estudos adicionais tornam-se necessários para a busca de planos de manejo que aumentem o tempo de vida útil da cama formada por bagana de carnaúba.(AU)

Animals , Female , Cattle , Animal Welfare , Heat Stress Disorders/prevention & control , Heat Stress Disorders/veterinary , Arecaceae
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1750-1758, set.-out. 2019. tab, graf, ilus
Article in Portuguese | VETINDEX, LILACS | ID: biblio-1038659


The effects of housing lactating sows at different locations in a shed with evaporative cooling system (ECS) on their thermoregulation and reproductive and productive performance of the sow and the litter in summer were determined. 34 females were used in the three lines of cages at these locations: near the pad cooling; in the middle of the shed and near the exhaust fans. The air temperature and the temperature and humidity index (THI) were lower near the pad cooling (22.38ºC, 71.84) than the middle (24.56ºC, 74.82) and near the exhaust fans (25.00°C, 75.62). Respiratory rate, rectal and surface temperatures were lower in sows near the pad cooling (43.67 breaths.min -1 , 38.40°C; 29.51°C) than in the center (52.04 breaths.min -1 ; 38.48ºC; 32.02ºC) and near the exhaust fans (56.38 breaths.min-1, 38.93ºC; 32.52ºC). The backfat thickness, the weaning-estrus interval and daily average consumption of the sows, number of weaning piglets, corporal mass and daily average gain of the piglets were not influenced by the location of housing in the shed. Lactating sows housed in the middle and near the exhaust fans in the ECS presented increased thermoregulation physiological variables, however, this did not impair the performance.(AU)

Animals , Female , Pregnancy , Swine/growth & development , Temperature , Body Temperature Regulation/physiology , Animal Welfare/organization & administration , Heat Stress Disorders/prevention & control , Housing, Animal/organization & administration
An. acad. bras. ciênc ; 89(2): 1259-1268, Apr.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-886691


ABSTRACT This study was conducted to evaluate the effect of vitamin E and selenium on performance, viability, productive efficiency, and yields of carcass, major cuts, and organs of broilers from 22 to 42 days submitted to cyclic-heat stress. The experimental design was randomized blocks, in a 2 × 3 factorial arrangement with two levels of selenium (0.1 and 0.3 mg/kg) and three levels of vitamin E (300, 400, and 500 mg/kg), plus a control treatment. Animals were submitted to a natural condition of high cyclic temperature. Organic selenium levels of 0.1 and 0.3 mg/kg associated with 300, 400, and 500 mg/kg of vitamin E were tested. The level of vitamin E did not affect the performance or production efficiency of broilers in the period from 22 to 33 days and 22 to 42 days. However, the selenium inclusion level of 0.3 mg/kg improved the viability in both phases. The yields of carcass, major cuts, intestine, and heart were not influenced by the levels of selenium and vitamin E, whereas abdominal fat for the selenium level 0.1 mg/kg decreased linearly with the inclusion in vitamin E.

Animals , Male , Female , Selenium/administration & dosage , Vitamin E/administration & dosage , Chickens/anatomy & histology , Chickens/physiology , Animal Feed , Antioxidants/administration & dosage , Reference Values , Selenium/analysis , Time Factors , Vitamin E/analysis , Body Weight , Weight Gain , Food, Fortified , Reproducibility of Results , Heat Stress Disorders/prevention & control , Antioxidants/analysis
Journal of Veterinary Research. 2014; 69 (1): 73-77
in Persian | IMEMR | ID: emr-157613


Heat stress can affect the health and performance of sheep. Researchers have investigated various methods to prevent the harmful effects of heat stress. In this study, injection of vitamin C on some biochemical parameters, red blood cells [RBC], hemoglobin [Hb], hematocrit [HCT] and white blood cells [WBC] in sheep under hyper acute heat stress were studied. Eight healthy male sheep in similar range of age [5 +/- 1 months] and weight [28.75 +/- 3.17 kg] were enrolled in this study. The sheep were divided into two groups. Both groups were placed in an environment with hyper-acute heat stress based on temperature-humidity index [THI].Vitamin C was injected intramuscularly on days 0, 1, 3 and 5.Blood samples were collected from the jugular vein on days 0. 1, 3, 5, and 7. Glucose, cortisol, cholesterol, triglycerides and blood components were measured and evaluated. Results were analyzed using statistical software SPSS [version 16]. The results showed that vitamin C injection has a significant effect on serum cortisol, glucose, hematocrit and white blood cells [p<0.05]. Vitamin C injection has lowering effects on serum cortisol and glucose during heat stress. Mechanism for attenuating the levels of cortisol and glucose by vitamin C is not well known. However, it may be done by decrease in cortisol synthesis or degradation. Increased hematocrit provided sufficient water to cool the body through perspiration. The present study probably shows a beneficial effect of injection of vitamin C on adaptation mechanisms against of heat-stressed sheep

Animals , Heat Stress Disorders/prevention & control , Heat Stress Disorders/veterinary , Ascorbic Acid , Sheep/blood
West Indian med. j ; 62(2): 140-144, Feb. 2013. ilus
Article in English | LILACS | ID: biblio-1045606


The present study summarizes the current knowledge of the heat and cold stress which might significantly affect military activities and might also occur among travellers who are not well adapted to weather variations during their journey. The selection of the best clothing is a very important factor in preserving thermal comfort. Our experiences with thermal manikin are also represented in this paper.

El presente trabajo resume los conocimientos actuales sobre el calor y el estrés por frío, que puede afectar significativamente la preparación militar, y pueden también ocurrir entre viajeros no bien adaptados a los cambios de tiempo y temperatura durante su viaje. La selección de la ropa mejor y más adecuada es también un factor muy importante para evitar el calor y el estrés por frío, y mantener el confort térmico. Nuestras experiencias con maniquíes térmicos también aparecen en este documento.

Humans , Protective Clothing , Heat Stress Disorders/prevention & control , Hypothermia/prevention & control , Manikins , Cold Temperature/adverse effects , Hot Temperature/adverse effects , Hypothermia/etiology
Braz. j. vet. res. anim. sci ; 50(6): 482-487, 2013. tab
Article in English | LILACS | ID: lil-789911


Solar radiation is responsible for bull body temperature elevation. An alternative to minimize heat stress is to use artificial shade. Thus, this study aimed to evaluate the effect of thermal stress reduction, through shade availability, on reproductive characteristics of Nellore bulls (Bos indicus). For this, ten bulls were divided in: Available artificial shade (AS, n = 5) and Unavailable shade (US, n = 5). Each group was kept in two hectare paddocks, in which shade availability for group AS was artificially created. Animals were submitted to a clinical-reproductive evaluation and seminal analyses. No interaction was observed between treatments (AS and US) and time (8 collections) for all analyzed variables (P>0.05). No significant effect (P > 0.05) of treatment was observed for all parameters analyzed. So, it can be concluded that the absence of shaded areas during summer does not negatively affect reproductive characteristics such as: scrotal circumference, testicular consistency, progressive motility, percentage of rapidly moving cells (Computer Assisted Semen Analysis - CASA), morphology or sperm viability in Nellore bulls raised in southeastern Brazil, considering that results could be different in other regions of the country where average temperature is higher...

A radiação solar é responsável pelo aumento da temperatura corpórea em touros. Uma alternativa para minimizar o estresse térmico é usar sombreamento artificial. Assim, este estudo teve como objetivo avaliar o efeito da redução do estresse térmico através da disponibilização de sombra artificial, sobre características reprodutivas de touros da raça Nelore (Bos indicus). Para isso, dez touros foram divididos em: Disponibilidade de sombra artificial (AS, n = 5) e Não-disponibilidade de sombra artificial (US, n=5). Cada grupo foi mantido em piquete de dois hectares cada, no qual a sombra para o grupo AS foi criada artificialmente. Os animais foram submetidos a avaliações clínicas-reprodutivas e análise seminal. Nenhuma interação foi observada entre os tratamentos (AS e US) e o tempo (8 coletas), para todas as variáveis analisadas (P > 0.05). Nenhum efeito significativo (P>0.05) de tratamento foi observado para os parâmetros analisados. Dessa forma, concluiu-se que a ausência de áreas sombreadas, durante o verão, não afetou negativamente as características reprodutivas como: circunferência escrotal, consistência testicular, motilidade progressiva, percentagem de células com movimentos rápidos (Computer Assisted Semen Analisys - CASA), morfologia e viabilidade espermática em touros da raça Nelore criados na região sudeste do Brasil, considerando que esse resultado pode ser diferente em outras regiões do país, onde as temperaturas ambientais são mais elevadas...

Animals , Male , Cattle , Semen Analysis/veterinary , Heat Stress Disorders/prevention & control , Heat Stress Disorders/veterinary , Livestock Industry
Journal of Health and Safety at Work. 2011; 1 (1): 39-46
in Persian | IMEMR | ID: emr-126119


Workers employed in outdoor occupations such as farm working, especially during rice harvest, are exposed to hot and humid environments that put them at risk for different kinds of heat-related disorders or heat stress. The aim of this study was to determine the susceptibility to heat-related disorders and prevention methods among a group of agriculture workers in one of the northern cities in Iran. This study is a descriptive-analytical and cross-sectional study which was done among 340 agricultures workers in a city [Sorkhrood] in Mazandaran province. The samples were collected from 42 villages using two stage cluster-randomized sampling method. The data were collected by means of tailor-made data collection sheet and analyzed using descriptive statistical indexes and Chi- square test, and p<0.05 was considered as significant. The findings indicated that the mean values of age and years of experience were 42.8 and 26 years, respectively. Almost half of the agriculture workers were overweight or obese, 34% illiterate, and 15% encountered chronic illnesses. Ninety five percent of the workers were not informed about prehydration in hot environment and none of them know about the consumption of electrolytes. According to Chi-square test result, there were no significant differences between the prevalence of headache as one of the early signs of heat -related disorders and other related factors. According to the results, agriculture workers based on their age distribution, education, body mass index, health knowledge, drug use and incidence of chronic diseases, are very vulnerable to heat-related disorders. Therefore, training on recognizing the early signs and doing control measures as essential element in heat stress prevention should be seriously considered

Humans , Heat Stress Disorders/prevention & control , Agricultural Workers' Diseases , Awareness , Cross-Sectional Studies
Biol. Res ; 43(2): 183-189, 2010. ilus
Article in English | LILACS | ID: lil-567533


The effects of vitamins C and E on layer chickens transported by road for 6 h during the hot dry season were investigated. Two experimental groups consisting of thirty Shika Brown layers were separately administered vitamins C and E orally just before transportation, while another 30 layers, which were only given sterile water, served as control. Blood samples analyzed before and after transportation in the control layers showed a decrease (p<0.05) in total white blood cell, (p<0.01) lymphocyte and monocyte values, and a signifcant (p<0.05) and (p<0.001) increase in the values of eosinophils and heterophils post-transportation, respectively. In the experimental groups, post-transportation values of total white blood cells, eosinophils and monocytes were not different (p>0.05) from those obtained before transportation. Heterophil/lymphocyte values were highest in the control group. The result showed that transportation was stressful for the control layers. Post-transportation egg production was not signifcantly (p>0.05) different in the vitamin E treated group, but values recorded for the vitamin C and control groups were signifcantly (p<0.05) and (p<0.001) reduced compared to pre-transportation. In conclusion, vitamins C and E administration ameliorated the adverse effect of road transportation stress during the hot dry season.

Animals , Female , Ascorbic Acid/therapeutic use , Chickens/blood , Heat Stress Disorders/veterinary , Oviparity/drug effects , Vitamin E/therapeutic use , Vitamins/therapeutic use , Heat Stress Disorders/prevention & control , Seasons , Transportation