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Various problems may arise during the road transportation of one-day-old broiler chickens from hatcheries to rearing houses. In this study, the transportation vehicles of a private company operating in the Bursa Region were physically examined, and the climate parameters of the trailer were observed. During these observations the exposure of animals to heat stress was measured, and the loss of life during transportation was revealed. Thirteen data logger values were placed in the trailer and their readings were recorded. While the highest heat stress is in the summer and the heat stress is the highest in the front and middle parts of the trailer, the least are in the first row and the last row in vehicles that use natural ventilation in the summer and mechanical air conditioning in the winter.(AU)

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A ovinocultura é uma importante atividade que produz proteínas de alto valor biológico, mas seus ganhos podem ser reduzidos em função do estresse ambiental. Isso reforça a importância de se estudar a relação entre o ambiente térmico e o animal, identificando animais mais adaptados e férteis, e melhores práticas de manejo. O ovino (Ovis aries) é um animal homeotérmico, que mantem sua temperatura corporal em equilíbrio dinâmico. Quando em estresse calórico, os ovinos usam mecanismos sensíveis e latentes para dissipar o calor acumulado, com destaque para o redirecionamento do fluxo sanguíneo, a ofegação e a sudorese. O escroto desempenha importante crucial na termorregulação dos testículos, os quais precisam funcionar sob em até 6,0oC abaixo da temperatura interna corpórea. A hipertermia testicular compromete a espermatogênese, reduz a concentração seminal, a motilidade progressiva e a viabilidade espermática. Ainda, leva a aumento dos defeitos morfológicos espermáticos, na produção de espécies reativas de oxigênio e na fragmentação do DNA espermático, diminuindo a capacidade fecundante. Tecnologias disruptivas para monitoramento do ambiente de produção, da termorregulação e do bem-estar dos animais já são realidade e se encontram em expansão, favorecendo a tomada de decisões em tempo real e o desempenho reprodutivo dos ovinos.

Sheep farming is a relevant activity that provides proteins of high biological value, but its gains can be reduced due to environmental stress. This reinforces the importance of studying the relationship between the thermal environment and the animal, identifying more adapted and fertile animals, and better management practices. Sheep (Ovis aries) are homeothermic animals and thus maintain their body temperature in a state of dynamic balance. Under heat stress, sheep dissipate accumulated heat through sensitive and latent mechanisms, primarily using redirection of blood flow, panting and sweating. The scrotum plays a crucial role in the thermoregulation of the testicles, which need to be maintained up to 6.0oC below the body core temperature. Testicular hyperthermia impairs spermatogenesis, reduces seminal concentration, progressive motility and sperm viability. Furthermore, it leads to an increase in sperm morphological defects, in the production of reactive oxygen species, and in sperm DNA fragmentation, reducing the fertilizing capacity. Disruptive technologies for monitoring the production systems, animal thermoregulation and welfare are already a reality and are expanding, favoring realtime decision making and the reproductive performance of sheep.

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In this study, immunohistochemistry and real-time fluorescent-based quantitative PCR were used to evaluate the expression of heat shock protein (HSP) 60, HSP70, and HSP90 in the small intestine of Wenchang chicks. Compared with the control group (CK), the positive expression of HSP60 and HSP60 mRNA in the heat stress group (HS) were initially higher and subsequently lower in the duodenum (p<0.01). In the HS jejunum, the levels of HSP60 were higher (p<0.01) and the HSP60 mRNA was lower (p<0.05). Whereas the levels of HSP60 in the HS ileum were higher (p<0.05) and then lower (p<0.01), and the HSP60 mRNA was higher (p<0.01). The levels of HSP70 were higher (p<0.01) and the HSP70 mRNA was lower in the duodenum (p<0.05), while the expression of both HSP70 and HSP70 mRNA was higher in the jejunum (p<0.01) and the ileum (p<0.05) of the HS. In the HS duodenum the levels of HSP90 were lower and then higher (p<0.01), and the HSP90 mRNA was higher (p<0.01). The expression of both HSP90 and HSP90 mRNA was higher in the HS jejunum (p<0.05). The levels of HSP90 were lower while the HSP90 mRNA was higher in the HS ileum (p<0.01). These results indicate that heat stress disturbed the expression of HSP60, HSP70, and HSP90 in the small intestine of chicks.(AU)

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The commercial exploitation of guinea fowl (Numidia meleagris) is a viable alternative for small rural properties in arid and semi-arid regions, as they are rustic birds and capable of withstanding the climatic adversities of these regions. The objective of this study was to evaluate the pupillary temperature, smaller pupillary diameter, larger pupillary diameter and pupil area of guinea fowl housed in a controlled environment, under two air temperatures: 26 ºC (thermal comfort zone) and 32 ºC (above the thermal comfort zone). The birds were distributed in a completely randomized design, with two treatments (air temperatures) and four replications (experimental box), with twelve birds each. The increase in air temperature resulted in a significant average increase (P < 0.05) of 6.0, 17.9, 18.6 and 38.4%, respectively, in pupillary temperature, smaller pupillary diameter, larger pupillary diameter and pupillary area of birds, being these measurements accurate in evaluation of thermal stress in homeothermic animals.(AU)

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RESUMO

The commercial exploitation of guinea fowl (Numidia meleagris) is a viable alternative for small rural properties in arid and semi-arid regions, as they are rustic birds and capable of withstanding the climatic adversities of these regions. The objective of this study was to evaluate the pupillary temperature, smaller pupillary diameter, larger pupillary diameter and pupil area of guinea fowl housed in a controlled environment, under two air temperatures: 26 ºC (thermal comfort zone) and 32 ºC (above the thermal comfort zone). The birds were distributed in a completely randomized design, with two treatments (air temperatures) and four replications (experimental box), with twelve birds each. The increase in air temperature resulted in a significant average increase (P < 0.05) of 6.0, 17.9, 18.6 and 38.4%, respectively, in pupillary temperature, smaller pupillary diameter, larger pupillary diameter and pupillary area of birds, being these measurements accurate in evaluation of thermal stress in homeothermic animals.

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RESUMO

In this study, immunohistochemistry and real-time fluorescent-based quantitative PCR were used to evaluate the expression of heat shock protein (HSP) 60, HSP70, and HSP90 in the small intestine of Wenchang chicks. Compared with the control group (CK), the positive expression of HSP60 and HSP60 mRNA in the heat stress group (HS) were initially higher and subsequently lower in the duodenum (p<0.01). In the HS jejunum, the levels of HSP60 were higher (p<0.01) and the HSP60 mRNA was lower (p<0.05). Whereas the levels of HSP60 in the HS ileum were higher (p<0.05) and then lower (p<0.01), and the HSP60 mRNA was higher (p<0.01). The levels of HSP70 were higher (p<0.01) and the HSP70 mRNA was lower in the duodenum (p<0.05), while the expression of both HSP70 and HSP70 mRNA was higher in the jejunum (p<0.01) and the ileum (p<0.05) of the HS. In the HS duodenum the levels of HSP90 were lower and then higher (p<0.01), and the HSP90 mRNA was higher (p<0.01). The expression of both HSP90 and HSP90 mRNA was higher in the HS jejunum (p<0.05). The levels of HSP90 were lower while the HSP90 mRNA was higher in the HS ileum (p<0.01). These results indicate that heat stress disturbed the expression of HSP60, HSP70, and HSP90 in the small intestine of chicks.

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The saddle is a particularly important piece of equipment when it comes to training horses. Any problem with this, or in its adjustment, can cause discomfort, pain and injury to the horses. The aim of this study was to analyze Australian saddles thermographically, in a quantitative way by quadrants, performing a primary detection of how pressure distribution occurs in Australian saddles commonly used in Mangalarga Marchador (MM) gaited horses during a basic riding course, in order to signal whether there is a need for a more complete assessment of saddle befitting this type of activity. For this purpose, ten similar Australian saddles used by ten MM horses were thermographically evaluated during a basic riding course. Thermographic images were obtained from the ventral face of the saddle before and after one hour of exercise. The images were divided into 9 quadrants and compared quantitatively before and after the ride. Quantitative analysis by quadrants including 3 central quadrants for assessing the gullet region was effective, providing the necessary detail for data analysis. Inappropriate contact of the gullet region with the animals back was demonstrated in 100% of the saddles, with the central quadrant of the gullet being the most affected, indicating the inadequacy of this type of saddle for MM in this activity. Therefore, there is a need for a more complete assessment of saddle befitting an Australian saddle type to this equestrian activity, aiming at improvements in animal welfare.(AU)

A sela é um equipamento de grande importância quando se trata do treinamento de equinos. Qualquer problema nesta, ou em seu ajuste, pode ocasionar desconforto, dores e lesões aos equinos. Objetivou-se, com o uso da análise termográfica quantitativa por quadrantes, realizar uma detecção primária de como ocorre a distribuição de pressão em selas australianas comumente utilizadas em cavalos da raça Mangalarga Marchador (MM) durante um curso básico de equitação, de forma a sinalizar se existe a necessidade de uma avaliação mais completa da adaptação de selas (Saddle Fitting)para este tipo de atividade. Para isso, foram avaliadas termograficamente dez selas australianas similares, utilizadas por dez animais da raça MM durante a realização de um curso básico de equitação para cavaleiros iniciantes. As imagens termográficas foram obtidas da face ventral da sela antes e após uma hora de exercício. As imagens foram divididas em nove quadrantes, comparadas quantitativamente, antes e depois da utilização, quanto a: temperatura do mesmo quadrante e equilíbrio entre quadrantes. A análise quantitativa por quadrantes incluindo três quadrantes centrais para avaliação da calha foi efetiva, proporcionando o detalhamento necessário para a análise dos dados. Demonstrou-se contato inapropriado da região da calha com dorso do animal em 100% das selas sendo quadrante central da calha o mais afetado, indicando a inadequação deste tipo de sela para MM nesta atividade. Havendo, portanto, necessidade de uma avaliação mais completa da adaptação de selas (Saddle Fitting) tipo australiana, a esta atividade equestre visando melhorias no bem estar animal.(AU)

Assuntos

RESUMO

The saddle is a particularly important piece of equipment when it comes to training horses. Any problem with this, or in its adjustment, can cause discomfort, pain and injury to the horses. The aim of this study was to analyze Australian saddles thermographically, in a quantitative way by quadrants, performing a primary detection of how pressure distribution occurs in Australian saddles commonly used in Mangalarga Marchador (MM) gaited horses during a basic riding course, in order to signal whether there is a need for a more complete assessment of saddle befitting this type of activity. For this purpose, ten similar Australian saddles used by ten MM horses were thermographically evaluated during a basic riding course. Thermographic images were obtained from the ventral face of the saddle before and after one hour of exercise. The images were divided into 9 quadrants and compared quantitatively before and after the ride. Quantitative analysis by quadrants including 3 central quadrants for assessing the gullet region was effective, providing the necessary detail for data analysis. Inappropriate contact of the gullet region with the animals back was demonstrated in 100% of the saddles, with the central quadrant of the gullet being the most affected, indicating the inadequacy of this type of saddle for MM in this activity. Therefore, there is a need for a more complete assessment of saddle befitting an Australian saddle type to this equestrian activity, aiming at improvements in animal welfare.

A sela é um equipamento de grande importância quando se trata do treinamento de equinos. Qualquer problema nesta, ou em seu ajuste, pode ocasionar desconforto, dores e lesões aos equinos. Objetivou-se, com o uso da análise termográfica quantitativa por quadrantes, realizar uma detecção primária de como ocorre a distribuição de pressão em selas australianas comumente utilizadas em cavalos da raça Mangalarga Marchador (MM) durante um curso básico de equitação, de forma a sinalizar se existe a necessidade de uma avaliação mais completa da adaptação de selas (Saddle Fitting)para este tipo de atividade. Para isso, foram avaliadas termograficamente dez selas australianas similares, utilizadas por dez animais da raça MM durante a realização de um curso básico de equitação para cavaleiros iniciantes. As imagens termográficas foram obtidas da face ventral da sela antes e após uma hora de exercício. As imagens foram divididas em nove quadrantes, comparadas quantitativamente, antes e depois da utilização, quanto a: temperatura do mesmo quadrante e equilíbrio entre quadrantes. A análise quantitativa por quadrantes incluindo três quadrantes centrais para avaliação da calha foi efetiva, proporcionando o detalhamento necessário para a análise dos dados. Demonstrou-se contato inapropriado da região da calha com dorso do animal em 100% das selas sendo quadrante central da calha o mais afetado, indicando a inadequação deste tipo de sela para MM nesta atividade. Havendo, portanto, necessidade de uma avaliação mais completa da adaptação de selas (Saddle Fitting) tipo australiana, a esta atividade equestre visando melhorias no bem estar animal.

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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 theassociation between 16 thermal stress indices and thermophysiological variables in young Nellore bulls raised in a tropicalpasture to determine the most effective parameter of heat stress to assist in the management of the thermal environmentand animal welfare.Materials, Methods & Results: Seventy-eight young Nellore bulls (Bos taurus indicus), with a mean age of 10.5 monthsand mean body weight of 242.09 ± 32.17 kg at first collection, and 17.92 months and body weight 335.80 ± 39.02 kg atlast 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 differencebetween the AST and air temperature (i.e., AST - AT) and between the RT and AST (i.e., RT - AST) defined the thermalgradient. For the evaluation of thermal environment, the dry bulb, wet bulb, and globe temperatures, and wind speed weremeasured. Relative humidity, mean radiant temperature, solar radiation, temperature humidity index (THI), black globaltemperature humidity index (BGHI), equivalent temperature index (ETI), environmental stress index (ESI), respiratory ratepredictor (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 relativehumidity was within the ideal limit for cattle. The average globe temperature was higher than the air temperature. Solarradiation presented very high values and wind speeds were very low. RT indicated normothermia in the cattle, and ASTand thermal gradient (i.e., AST - AT) indicated thermal comfort...(AU)

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The study aimed at comparing the effects of the supplementation of natural antioxidant sources to a reduced crude protein diet on the performance, carcass traits, blood parameters, liver antioxidant enzyme activities and meat lipid peroxidation of Japanese quails exposed to heat stress. A total of 640 14-day-old male Japanese quails were exposed to two different temperature treatments (TT): thermoneutral (TN) or heat stress (HS)and were fed five different dietary treatments (DTs). A normal-protein diet (SCP) was formulated according to the National Research Council (24% CP). The reduced crude protein diet (RCP) was formulated to contain 3% less protein than that of the SCP diet. Three additional diets were prepared by supplementing the RCP with200 mg/kg of -tocopherol acetate (RCP+TA200), pomegranate peel extract (RCP+PPE200) or apple peel extract (RCP+APE200). HS significantly deteriorated the growth performance of quails throughout the experiment. Quails fed the SCP and RCP+PPE200 presented higher hematocrit values. Feeding the RCP+TA200 and RCP+PPE200 diets reduced the blood heterophil/lymphocyte (H/L) ratio compared with the other diets. Quails fed the SCP, RCP+TA200, RCP+PPE200 and RCP+APE200 diets presented higher liver catalase and glutathione peroxidase activities, plasma uric acid level, and lower meat malondialdehyde value at 7days of age compared with those fed the RCP diet. In conclusion, the results show that the extracts of pomegranate peel and apple peel can be used as alternative natural antioxidant sources to vitamin E in the diets of Japanese quails exposed to heat stress and fed a reduced crude protein diet.(AU)

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RESUMO

The study aimed at comparing the effects of the supplementation of natural antioxidant sources to a reduced crude protein diet on the performance, carcass traits, blood parameters, liver antioxidant enzyme activities and meat lipid peroxidation of Japanese quails exposed to heat stress. A total of 640 14-day-old male Japanese quails were exposed to two different temperature treatments (TT): thermoneutral (TN) or heat stress (HS)and were fed five different dietary treatments (DTs). A normal-protein diet (SCP) was formulated according to the National Research Council (24% CP). The reduced crude protein diet (RCP) was formulated to contain 3% less protein than that of the SCP diet. Three additional diets were prepared by supplementing the RCP with200 mg/kg of -tocopherol acetate (RCP+TA200), pomegranate peel extract (RCP+PPE200) or apple peel extract (RCP+APE200). HS significantly deteriorated the growth performance of quails throughout the experiment. Quails fed the SCP and RCP+PPE200 presented higher hematocrit values. Feeding the RCP+TA200 and RCP+PPE200 diets reduced the blood heterophil/lymphocyte (H/L) ratio compared with the other diets. Quails fed the SCP, RCP+TA200, RCP+PPE200 and RCP+APE200 diets presented higher liver catalase and glutathione peroxidase activities, plasma uric acid level, and lower meat malondialdehyde value at 7days of age compared with those fed the RCP diet. In conclusion, the results show that the extracts of pomegranate peel and apple peel can be used as alternative natural antioxidant sources to vitamin E in the diets of Japanese quails exposed to heat stress and fed a reduced crude protein diet.

Assuntos

RESUMO

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 theassociation between 16 thermal stress indices and thermophysiological variables in young Nellore bulls raised in a tropicalpasture to determine the most effective parameter of heat stress to assist in the management of the thermal environmentand animal welfare.Materials, Methods & Results: Seventy-eight young Nellore bulls (Bos taurus indicus), with a mean age of 10.5 monthsand mean body weight of 242.09 ± 32.17 kg at first collection, and 17.92 months and body weight 335.80 ± 39.02 kg atlast 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 differencebetween the AST and air temperature (i.e., AST - AT) and between the RT and AST (i.e., RT - AST) defined the thermalgradient. For the evaluation of thermal environment, the dry bulb, wet bulb, and globe temperatures, and wind speed weremeasured. Relative humidity, mean radiant temperature, solar radiation, temperature humidity index (THI), black globaltemperature humidity index (BGHI), equivalent temperature index (ETI), environmental stress index (ESI), respiratory ratepredictor (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 relativehumidity was within the ideal limit for cattle. The average globe temperature was higher than the air temperature. Solarradiation presented very high values and wind speeds were very low. RT indicated normothermia in the cattle, and ASTand thermal gradient (i.e., AST - AT) indicated thermal comfort...

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This research aimed to determine the most appropriate thermal comfort index for buffaloesreared in the Eastern Amazon, Pará, Brazil. Twenty male Murrah buffaloes were used, and data on climatevariables, rectal temperature (RT), body surface temperature (BST), and respiratory rate (RR) wererecorded. Subsequently, the following indices were calculated: Temperature and Humidity Index (THI),Global Temperature and Humidity Index (GTHI), Benezras Thermal Comfort Index (BTCI), IbériasHeat Tolerance Index (IHTI), the general, effective, and practical Buffalo Comfort Climatic ConditionsIndices (BCCCIg, BCCCIe, and BCCCIp, respectively) and the general, effective, and practical BuffaloEnvironmental Comfort Indices (BECIg, BECIe, and BECIp, respectively) in the morning and afternoon.Higher values for THI, GTHI, RT, BST, RR, BTCI, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe, andBECIp were observed in the afternoon, and the highest IHTI values were found in the morning. A positivecorrelation was found among the physiological variables and THI, GTHI, BTCI, BCCCIg, BECIg,BCCCIe, BECIe, BCCCIp, BECIp, while a negative correlation was found for RT and BST with IHTI. Theindices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp, and BECIp were determined to be veryefficient to assess the thermal comfort status of buffaloes under the conditions of the present research.(AU)

A pesquisa objetivou determinar o índice de conforto térmico mais adequado para búfaloscriados na Amazônia Oriental, Pará, Brasil. Foram utilizados vinte búfalos Murrah. Foram registradosdados de variáveis climáticas e temperatura retal (TR), temperatura da superfície corporal (TSC) efrequência respiratória (FR), e foram calculados os índices: Índice de Temperatura e Umidade (ITU),Índice de Temperatura de Globo e Umidade (ITGU), Índice de Conforto Térmico de Benezra (ICB),Índice de Tolerância ao Calor de Ibéria (ITCI), Índice de Condições Climáticas de Conforto para búfalosgeral (BCCCIg), efetivo (BCCCIe) e prático (BCCCIp) e Índice de Conforto Ambiental para búfalos geral(BECIg), efetivo (BECIe) e prático (BECIp), nos períodos da manhã e da tarde. Foram observados valoresde ITU, ITGU, TR, TSC, FR, ICB, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe e BECIp mais elevados à tarde. Os maiores valores de ITCI foram encontrados de manhã. Houve correlação positiva entre as variáveis fisiológicas e ITU, ITGU, ITCI, BCCCIg, BECIg, BCCCIe, BECIg, BCCCIe, BECIp, enquanto uma correlação negativa foi encontrada para TR e TSC com ITCI. Os índices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp e BECIp são eficientes para avaliar o estado de conforto térmico dos búfalos na Amazônia Oriental.(AU)

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This research aimed to determine the most appropriate thermal comfort index for buffaloesreared in the Eastern Amazon, Pará, Brazil. Twenty male Murrah buffaloes were used, and data on climatevariables, rectal temperature (RT), body surface temperature (BST), and respiratory rate (RR) wererecorded. Subsequently, the following indices were calculated: Temperature and Humidity Index (THI),Global Temperature and Humidity Index (GTHI), Benezra’s Thermal Comfort Index (BTCI), Ibéria’sHeat Tolerance Index (IHTI), the general, effective, and practical Buffalo Comfort Climatic ConditionsIndices (BCCCIg, BCCCIe, and BCCCIp, respectively) and the general, effective, and practical BuffaloEnvironmental Comfort Indices (BECIg, BECIe, and BECIp, respectively) in the morning and afternoon.Higher values for THI, GTHI, RT, BST, RR, BTCI, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe, andBECIp were observed in the afternoon, and the highest IHTI values were found in the morning. A positivecorrelation was found among the physiological variables and THI, GTHI, BTCI, BCCCIg, BECIg,BCCCIe, BECIe, BCCCIp, BECIp, while a negative correlation was found for RT and BST with IHTI. Theindices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp, and BECIp were determined to be veryefficient to assess the thermal comfort status of buffaloes under the conditions of the present research.

A pesquisa objetivou determinar o índice de conforto térmico mais adequado para búfaloscriados na Amazônia Oriental, Pará, Brasil. Foram utilizados vinte búfalos Murrah. Foram registradosdados de variáveis climáticas e temperatura retal (TR), temperatura da superfície corporal (TSC) efrequência respiratória (FR), e foram calculados os índices: Índice de Temperatura e Umidade (ITU),Índice de Temperatura de Globo e Umidade (ITGU), Índice de Conforto Térmico de Benezra (ICB),Índice de Tolerância ao Calor de Ibéria (ITCI), Índice de Condições Climáticas de Conforto para búfalosgeral (BCCCIg), efetivo (BCCCIe) e prático (BCCCIp) e Índice de Conforto Ambiental para búfalos geral(BECIg), efetivo (BECIe) e prático (BECIp), nos períodos da manhã e da tarde. Foram observados valoresde ITU, ITGU, TR, TSC, FR, ICB, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe e BECIp mais elevados à tarde. Os maiores valores de ITCI foram encontrados de manhã. Houve correlação positiva entre as variáveis fisiológicas e ITU, ITGU, ITCI, BCCCIg, BECIg, BCCCIe, BECIg, BCCCIe, BECIp, enquanto uma correlação negativa foi encontrada para TR e TSC com ITCI. Os índices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp e BECIp são eficientes para avaliar o estado de conforto térmico dos búfalos na Amazônia Oriental.

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Heat tolerance in poultry production was obtained attention due to the need for genetic lines that can withstand climate changes. This study aimed at investigating heat tolerance in commercial and native broiler genetics, as well as the physiological and growth performance responses of HSP70 genotypes submitted to heat stress. In Experiment I, heterophil:lymphocyte (H:L) ratio, as an indicator of heat tolerance, was compared between commercial broilers (n = 100) and Thai native chickens (n = 100). Growing chickens (with similar initial weight) of each genetic strain were randomly divided into two groups: 1) thermoneutral environment (26 oC ± 2 oC) and 2) heat stress (36 oC ± 2 oC). The results showed that native chickens originating from a tropical environment presented lower H:L ratio and mortality rate compared with commercial broilers. In Experiment II, HSP70 genotypes were compared. PCR-RFLP was applied to identify the genotypes (C1C1, n = 38; C1C2, n = 38; and C2C2, n = 28). Ten-week-old chickens of each genotype were evaluated in the same environments described in Experiment I. Heat-stress indicators - respiratory rate (RR), cloacal temperature (CT), packed cell volume (PCV), and average daily gain (ADG) - were measured for three weeks. The significant difference in PCV indicated that C2C2 chickens were less tolerant to heat stress compared to other genotypes. The RR, CT, and ADG were not significantly different among all genotypes. Since the C2C2 genotype was shown to be sensitive to heat stress, C1C1 and C1C2 could be used as markers for heat-tolerant genetic strains of Thai indigenous chickens and hybrid commercial lines.(AU)

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Heat tolerance in poultry production was obtained attention due to the need for genetic lines that can withstand climate changes. This study aimed at investigating heat tolerance in commercial and native broiler genetics, as well as the physiological and growth performance responses of HSP70 genotypes submitted to heat stress. In Experiment I, heterophil:lymphocyte (H:L) ratio, as an indicator of heat tolerance, was compared between commercial broilers (n = 100) and Thai native chickens (n = 100). Growing chickens (with similar initial weight) of each genetic strain were randomly divided into two groups: 1) thermoneutral environment (26 oC ± 2 oC) and 2) heat stress (36 oC ± 2 oC). The results showed that native chickens originating from a tropical environment presented lower H:L ratio and mortality rate compared with commercial broilers. In Experiment II, HSP70 genotypes were compared. PCR-RFLP was applied to identify the genotypes (C1C1, n = 38; C1C2, n = 38; and C2C2, n = 28). Ten-week-old chickens of each genotype were evaluated in the same environments described in Experiment I. Heat-stress indicators - respiratory rate (RR), cloacal temperature (CT), packed cell volume (PCV), and average daily gain (ADG) - were measured for three weeks. The significant difference in PCV indicated that C2C2 chickens were less tolerant to heat stress compared to other genotypes. The RR, CT, and ADG were not significantly different among all genotypes. Since the C2C2 genotype was shown to be sensitive to heat stress, C1C1 and C1C2 could be used as markers for heat-tolerant genetic strains of Thai indigenous chickens and hybrid commercial lines.

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The study objectify to evaluate the adaptability of pregnant sheep of the Dorper, Santa Ines and mixed(Dorper ½ ½ Santa Ines) to the tropical climate through serologic possible modifications of triiodothyronine(T3) and thyroxine (T4). The experiment was conducted at Malhada Vermelha farm in Lagoa Alegre - PI, 21sheep were used in gestational middle third, 7 of Dorper, 7 Santa Ines and 7 mixed (Dorper x Santa Ines), all insatisfactory clinical conditions and under the same management conditions. These were evaluated respiratoryrate, rectal temperature and collected blood samples for hormone dosage four times in each climatic periodMarch, July and October. Later they were measured Thyroxine (Total T4) and triiodothyronine (T3) by ELISA.T3 dosages remained within the normal range for the species, while T4 was below. It was concluded that themost adapted breed is Santa Ines.

Assuntos

RESUMO

This study evaluated the quality of ejaculated from adapted breeds of goats as the morphologic aspects,functional and thermoresistance. An aliquot of the pool of each breed was used for morphological evaluation bywet preparation, quantifying sperm defects and dividing them into classes. The samples were cryopreservedusing TK3000 machine and evaluated by thermoresistance test by checking motility and sperm vigor every hour.For plasma membrane functionality analysis, was used hiposmotic test. There was no difference (P > 0.05)between the breeds in all sperm defects before and after cryopreservation, as well as for the thermoresistancetimes for motility and sperm vigor (P > 0.05). There was a significant reduction in motility and sperm vigor 120minutes after thawing of the samples. There was no difference (P > 0.05) between the percentage of sperm withfunctional membrane between the evaluated breeds. Therefore, the evaluated breeds have morphology,functionality and similar sperm thermoresistance.

Assuntos

RESUMO

The study objectify to evaluate the adaptability of pregnant sheep of the Dorper, Santa Ines and mixed(Dorper ½ ½ Santa Ines) to the tropical climate through serologic possible modifications of triiodothyronine(T3) and thyroxine (T4). The experiment was conducted at Malhada Vermelha farm in Lagoa Alegre - PI, 21sheep were used in gestational middle third, 7 of Dorper, 7 Santa Ines and 7 mixed (Dorper x Santa Ines), all insatisfactory clinical conditions and under the same management conditions. These were evaluated respiratoryrate, rectal temperature and collected blood samples for hormone dosage four times in each climatic periodMarch, July and October. Later they were measured Thyroxine (Total T4) and triiodothyronine (T3) by ELISA.T3 dosages remained within the normal range for the species, while T4 was below. It was concluded that themost adapted breed is Santa Ines.(AU)

Assuntos