Broiler behavior: influence of thermal stress, age, and period of the day

This study evaluated the behavior of broiler chickens subjected to thermal stress during different periods of the day and age of birds. A total of 180 one-day-old male broiler chicks were allocated to three chambers. Each chamber contained five boxes, with 12 chicks/box. Birds were assigned to a completely randomized design. The birds were filmed, and the images recorded every minute during the two periods: morning (from 08:00 to 09:00 h) and afternoon (from 17:00 to 18:00 h), at 7, 14, and 35 d of age. The frequency of the behavioral category (water intake, feed intake, resting, exploration, and comfort) was determined. Data were subjected to variance analysis for mixed models with rearing temperatures (cold, usual, and hot) and age of birds (7, 14, and 35 d) as subdivided plot, and periods of the day (morning and afternoon) as sub-subdivided plot. Birds at cold and usual temperatures showed higher feed intake than those at hot temperature in the morning. Birds exposed to cold and usual temperatures explored the environment less frequently at 35 d when compared with 14 d. However, chickens at hot temperature showed decreased exploration according to the increase of age. Birds spent more time feeding during the morning, regardless of age and rearing temperature. Also, during this period of the day, chickens spent most of the time exploring the environment. The frequency of feed intake and exploration decreases with the increase of age. The similarity of behavior between chickens reared at cold and usual temperatures may be due to a change in the thermal comfort zone of the birds. It suggests that the real thermal comfort temperature is between the two temperature ranges studied (cold and usual).

Tracking of thermal microbial shock proteins and genomic variation of Bacillus cereus due to some abiotic stresses / Rastreamento de proteínas de choque microbiano térmico e variação genômica de Bacillus cereus devido a alguns estresses abióticos

Bacillus cereus is considered the most potent bacterial strain in terms of the increment in induced proteins during thermal treatment at 52 °C for 90 min. Protein production in food-born microorganism (Bacillus cereus) recovered from contaminated food was investigated in response to heat shock treatment. Bacterial tolerance towards pH, salinity, and temperature at various levels was also investigated. Heat-shock proteins (HSPs) produced when exposed to 52 °C for up to 60 minutes led to significant differences (30%) above the untreated control (37 °C), and the maximum difference was recorded at 52°C at 90 minutes. ISSR detected a higher number of bands/primer than RAPD (13.7 vs. 12.7, respectively), and more polymorphic bands (10.7 vs. 8.4 bands/primer, respectively). The untreated bacterial strain did not grow at pH levels lower than 3, whereas the thermally treated strain grew significantly at pH two. A consistent increase in HSPs was observed, with a gradual increase in salinity of less than 16%. Surprisingly, the gradual increase in temperature did not induce tolerance against higher temperatures. However, a significant growth rate was noticed in response to heat-shocked treatments. The untreated Bacillus cereus demonstrated antibiotic resistance to gentamycin and clindamycin (1.54 and 1.65 cm, respectively), much lower than the corresponding inhibition areas with preheat-treated test pathogen which were recorded (2.37 and 2.49 cm, respectively).

Bacillus cereus é considerada a cepa bacteriana mais potente em termos de incremento de proteínas induzidas durante o tratamento térmico a 52 °C por 90 min. A produção de proteínas em microorganismos de origem alimentar (Bacillus cereus) recuperados de alimentos contaminados foi investigada em resposta ao tratamento de choque térmico. A tolerância bacteriana ao pH, salinidade e temperatura em vários níveis também foram investigadas. Proteínas de choque térmico (HSPs) produzidas quando expostas a 52 °C por até 60 minutos levaram a diferenças significativas (30%) acima do controle não tratado (37 °C), e a diferença máxima foi registrada a 52 °C em 90 minutos . O ISSR detectou um maior número de bandas/iniciador do que o RAPD (13,7 vs. 12,7, respectivamente) e mais bandas polimórficas (10,7 vs. 8,4 bandas/iniciador, respectivamente). A cepa bacteriana não tratada não cresceu em níveis de pH abaixo de 3, enquanto a cepa tratada termicamente cresceu significativamente em pH dois. Observou-se aumento consistente de HSPs, com aumento gradual da salinidade inferior a 16%. Surpreendentemente, o aumento gradual da temperatura não induziu tolerância a temperaturas mais altas. No entanto, uma taxa de crescimento significativa foi observada em resposta aos tratamentos de choque térmico. O Bacillus cereus não tratado demonstrou resistência antibiótica à gentamicina e clindamicina (1,54 e 1,65 cm, respectivamente), muito menor do que as áreas de inibição correspondentes com patógeno de teste pré-tratado que foram registradas (2,37 e 2,49 cm, respectivamente).

Key points for the thermal comfort of water buffaloes in Eastern Amazon / Pontos-chave do conforto térmico de bubalinos na Amazônia Oriental

ABSTRACT: This study presented relevant aspects about the Amazonian environment and how it impacts the thermal comfort of domestic buffaloes (Bubalus bubalis) raised in the Eastern Amazon. Furthermore, strategies for monitoring and mitigating animal heat stress are presented, based on research results with the species. Although domestic buffaloes are considered adaptable animals, exposure to intense solar radiation causes thermal discomfort. This condition is expressed in biophysical indicators, in metabolic, endocrine, behavioral responses, and in body thermographic patterns. Therefore, the biometeorological monitoring of production is crucial to support decision-making regarding environmental management strategies, genetic selection of thermotolerant individuals, and increase in animal welfare. Lastly, the use of silvopastoral systems can help to provide higher thermal comfort, which is a condition that directly impacts the productivity of milk and meat buffaloes when they are raised in tropical regions, such as in the Eastern Amazon.

RESUMO: Objetivou-se apresentar aspectos relevantes sobre o ambiente amazônico e como este impacta no conforto térmico de búfalos domésticos (Bubalus bubalis) criados na Amazônia Oriental. Adicionalmente, são apresentadas estratégias para monitoramento e mitigação do estresse térmico animal, a partir de resultados de pesquisa com a espécie. Apesar dos búfalos domésticos serem considerados animais adaptáveis, a exposição à intensa radiação solar provoca desconforto térmico. Essa condição é expressa em indicadores biofísicos, nas respostas metabólicas, endócrinas, comportamentais e nos padrões termográficos corporais. Assim, o monitoramento biometeorológico da produção é crucial para subsidiar tomadas de decisão em relação a estratégias de manejo ambiental, seleção genética de indivíduos termotolerantes e incremento do bem-estar animal. Por fim, o uso de sistemas silvipastoris pode auxiliar na oferta de maior conforto térmico, que é uma condição que impacta diretamente na produtividade de bubalinos de leite e carne, quando estes são criados em regiões tropicais, como na Amazônia Oriental.

Oxidative activity of corpus luteum and ovarian parenchyma in Bos taurus indicus heifers

Abstract The aim of this study was to evaluate the oxidative stress in ovaries and corpus luteum (CL) of Bos taurus indicus females and the oxidant effect of CL in ovarian tissues in regions near, intermediate, or distant from it. Ovaries (n=12) of Nelore heifers (n=6) were collected from a slaughterhouse and fragmented. Experiment 1, each ovary was obtained from three fragments, resulting in 18 fragments of ovaries with CL (OV+CL) and another 18 fragments of ovaries without CL (OV-CL). Three fragments were generated from CL, totaling 18 CL fragments. In experiment 2, the ovarian fragments were removed from specific regions near, intermediate, or distant from the CL. All the fragments were placed in Eppendorf-type microtubes (1 mL), kept in a thermal container at 4 ºC, and then stored in a -80 ºC freezer for analysis of oxidative stress (TBARS and NBT) and antioxidant potential (FRAP and ABTS). In the antioxidant activity analysis, luteal tissues showed more antioxidant activity than ovarian tissue (FRAP = P < 0.0001; ABTS = P < 0.02). In the oxidative stress analysis, CL had lower levels of reactive oxygen species (ROS; TBARS = P < 0.03; NBT = P < 0.0001) than ovarian tissues. There was no difference in antioxidant activity and oxidative stress between the fragments obtained from different regions (OV+CL versus OV-CL; P > 0.05). The presence of CL in the ovaries of Bos taurus indicus females did not influence the oxidative stress or antioxidant potential of the gonad. Thus, the removal of ovarian fragments with or without the presence of CL indicates that biotechnologies such as in vitro follicle cultivation is possible.

Surviving heat: Resilience of Nellore bulls to solar radiation exposure

We aimed to assess the physiological and biophysical responses of Nellore bulls exposed to solar radiation in semiarid conditions throughout the day. Sixteen Nellore bulls were examined in Tibau city, Northeast Brazil (5°52ʹ South, 37°20ʹ West, and 37 m above sea level) over four nonconsecutive days, with data collection taking place at one-hour intervals between 7:00 am and 5:00 pm. Four animals were analyzed each day and kept exposed to the sun for the duration of the study. The average age of the animals was three years, and their average body weight was 650±32 kg. The meteorological station measured air temperature (°C), relative humidity (%), solar radiation (W.m-2 ), and black globe temperatures (°C) every minute, while a digital anemometer thermohygrometer measured wind speed (m.s-1 ) at the same time. Respiratory rate (breaths.min-1 ), expired air temperature (°C), rectal temperature (°C), and body surface temperature (°C) were measured as physiological variables. Biophysical equations were used to estimate the sensible and latent heat transfer mechanisms (W.m-2 ). The air temperature ranged from 28.5 to 32.5°C, and direct solar radiation was between 21 and 891 W.m-². Between 11:00 am and 1:00 pm, the study observed heat gain through longwave radiation, which reached an average of 250 W.m-2 , with a significant increase (P < 0.05) in respiratory rate and body surface temperature during this time. Convection was significant in heat dissipation, particularly when the wind speed was increased from 11:00 am. However, latent heat loss mechanisms were more effective in losing excess body heat under total sun exposure, despite the positive effect of convection. The study findings showed that Nellore bulls maintained their body temperature within a narrow range even when exposed to high solar radiation, thus demonstrating the efficiency of physiological and biophysical mechanisms during times of greater thermal challenge.(AU)

Thermal comfort and photoperiod on the productive performance of sows and piglets / Conforto térmico e fotoperíodo sobre o desempenho produtivo de porcas e de leitões

ABSTRACT: Pigs have difficulty in performing heat exchange and; therefore, it is important to consider the environmental factors that impact their productive performance. This study evaluated the effect of thermal comfort and photoperiod on the productive performance of sows during pregnancy and of nursery piglets. Zootechnical data were obtained from a commercial farm. The temperature-humidity index (THI) was used as the parameter to determine comfort or thermal stress of the sow. The parameters of the sows during pregnancy and nursery piglets were analyzed considering the criteria of comfort, stress, and four photoperiods. The correlation between photoperiod and THI was high and positive, which demonstrated the associated effect of these variables. More significant effects were observed under conditions of comfort and shorter photoperiods. In conclusion, thermal comfort and photoperiod influenced the parameters evaluated during pregnancy and in the nursery, and the strong association between THI and photoperiod suggested that environmental control favors productive parameters in commercial farms.

RESUMO: Os suínos são animais que apresentam dificuldade em realizar trocas de calor, por esse motivo é importante considerar os fatores ambientais que impactam seu desempenho produtivo. O objetivo do presente trabalho foi avaliar o efeito do conforto térmico e do fotoperíodo, sobre o desempenho produtivo das porcas na gestação e leitões na maternidade. Os dados zootécnicos foram obtidos de uma granja comercial. O índice de temperatura e umidade (ITU) foi utilizado como parâmetro para o conforto ou o estresse térmico da matriz. Foram analisados os parâmetros das fêmeas no período gestacional e dos leitões na maternidade, considerando os critérios de conforto, estresse e quatro faixas de fotoperíodos. A correlação entre o fotoperíodo e ITU foi alta e positiva, demonstrando efeito associado dessas variáveis. Foram observados mais efeitos significativos em situações de conforto e faixas de menor fotoperíodo. Em conclusão, o conforto térmico e o fotoperíodo influenciaram os parâmetros avaliados na gestação e na maternidade e a alta associação ITU e fotoperíodo sugere que o controle ambiental pode favorecer parâmetros produtivos em granjas comerciais.

Identical thermal stress coupled with different temperature and humidity combinations affects nutrient digestibility and gut metabolites of laying hens

The present study investigated whether the same temperature-humidity index (THI) values under different conditions of air temperature and relative humidity (RH) would affect the thermoregulatory, nutritional, and behavioral responses of laying hens. One hundred twenty Hy-Line Brown laying hens (60-weeks-old) were divided equally in two environmental chambers: 26 °C with 70% RH (hRH75) and 30 °C with 30% RH (hT75) for 28 days. The two ambient environments (hRH75 and hT75) had an identical THI value of 75, calculated using an empirical formula for laying hens. Neither hRH75 nor hT75 affected rectal and body-surface temperatures and heart and respiratory rates. The concentration of volatile fatty acids in fecal excreta were altered by the thermal treatments. hT75 vs. hRH75 decreased the proportion of acetate and increased the proportion of propionate in fecal samples. hT75 vs. hRH75 lowered the digestibility of dry matter, crude protein, and neutral detergent fiber at 14 days. Thermal treatments did not affect heat stress-associated behavioral responses including feeding, drinking, panting, and wing elevation at any stage. Laying hens exposed to the same THI at different temperatures and RH exhibit equal physiological responses including rectal and body-surface temperatures, heart and respiratory rates, and behavioral responses. Nonetheless, high-temperature treatment (hT75; 30 °C and 30% RH) vs. low temperature treatment (hRH75; 26 °C and 70% RH) affects nutrient digestibility and gut metabolites, suggesting that there are negligible but discernable responses to temperature in the gut physiology.(AU)

Seasonality effect on the physiological and productive responses of crossbred dairy cows to the equatorial Amazon climate / Efeito da sazonalidade sobre as respostas fisiológicas e produtivas de vacas leiteiras mestiças ao clima amazônico equatorial

The objective of this study was to evaluate the seasonal effect of months of the year upon the physiological and productive responses of crossbred dairy cows raised in an Amazonian climate. Twenty lactating cows were evaluated, fed on Brachiaria decumbens pasture, with free access to water and mineral supplementation. Data from climate variables air temperature (AT), relative humidity (RH), rainfall (RA) and temperature and humidity index (THI) were recorded dur ing the months of January to April 2019. The physiological data collected were: respiratory rate (RR, mov/min), heart rate (HR, beats/min), rectal temperature (RT, ºC), udder surface temperature (UST, ºC), body surface temperature (BST, ºC), dorsum surface temperature (DST, ºC), front surface temperature (FST, ºC) and rear shin temperature (RST). Milk production (MP) was also measured. There was a significant difference (P<0.05) of RST and RR with values ranging from 34.8 to 35.5°C and 32.0 to 36.2 mov/min, respectively. There were no significant difference (P>0.05) for BST, and the values for MP and THI were 3.8; 3.8; 4.6; 4.1 kg and 77.7; 79.7; 80.6; 80.1, respectively. It was concluded that there was a seasonal effect of the months of the year evaluated on the respiratory rate of animals, however, it did not change the MP and the THI. The Amazon environment is conducive to causing thermal stress in lactating cows raised on pasture, requiring the use of shading to facilitate the ability of these animals to dissipate heat.(AU)

O objetivo desse estudo foi avaliar os efeitos sazonais dos meses do ano sobre as respostas fisiológicas e produtivas de vacas leiteiras mestiças criadas em clima amazônico. Foram avaliadas 20 vacas lactantes, alimentadas com pasto de Brachiaria decumbens, com acesso livre a água e suplementação mineral. Foram registrados dados das variáveis climáticas temperatura do ar (TA), umidade relativa do ar (UR), precipitação pluviométrica (PP) e índice de temperatura e Umidade (ITU) durante os meses de janeiro a abril de 2019. Os dados fisiológicos coletados foram: frequência respiratória (FR, mov/min), frequência cardíaca (FC, bat./min), temperatura retal (TR, ºC), temperatura superficial do úbere (TSU, ºC), temperatura superfície corporal (TSC, ºC), temperatura superficial do dorso (TSD, ºC), temperatura superficial da fronte (TSF, ºC) e temperatura superficial da canela (TSCA, °C). Também foi mensurada a produção de leite (PL, kg). Houve diferença significativa (P<0,05) da TSCA e FR com valores variando de 34,8 a 35,5°C e 32,0 a 36,2 mov/min, respectivamente. Não houve diferença significativa (P>0,05) para TSC e os valores observados para PL e ITU foram 3,8; 3,8; 4,6; 4,1 kg e 77,7; 79,7; 80,6; 80,1, respectivamente. Houve efeito sazonal dos meses avaliados sobre a taxa respiratória dos animais, no entanto, isso não alterou a PL nem o ITU. O ambiente amazônico é propício a causar estresse térmico em vacas lactantes mantidas a pasto, sendo necessário o uso de sombreamento para facilitar a capacidade de dissipação de calor corporal desses animais.(AU)

Key points for the thermal comfort of water buffaloes in Eastern Amazon / Pontos-chave do conforto térmico de bubalinos na Amazônia Oriental

This study presented relevant aspects about the Amazonian environment and how it impacts the thermal comfort of domestic buffaloes (Bubalus bubalis) raised in the Eastern Amazon. Furthermore, strategies for monitoring and mitigating animal heat stress are presented, based on research results with the species. Although domestic buffaloes are considered adaptable animals, exposure to intense solar radiation causes thermal discomfort. This condition is expressed in biophysical indicators, in metabolic, endocrine, behavioral responses, and in body thermographic patterns. Therefore, the biometeorological monitoring of production is crucial to support decision-making regarding environmental management strategies, genetic selection of thermotolerant individuals, and increase in animal welfare. Lastly, the use of silvopastoral systems can help to provide higher thermal comfort, which is a condition that directly impacts the productivity of milk and meat buffaloes when they are raised in tropical regions, such as in the Eastern Amazon.

Objetivou-se apresentar aspectos relevantes sobre o ambiente amazônico e como este impacta no conforto térmico de búfalos domésticos (Bubalus bubalis) criados na Amazônia Oriental. Adicionalmente, são apresentadas estratégias para monitoramento e mitigação do estresse térmico animal, a partir de resultados de pesquisa com a espécie. Apesar dos búfalos domésticos serem considerados animais adaptáveis, a exposição à intensa radiação solar provoca desconforto térmico. Essa condição é expressa em indicadores biofísicos, nas respostas metabólicas, endócrinas, comportamentais e nos padrões termográficos corporais. Assim, o monitoramento biometeorológico da produção é crucial para subsidiar tomadas de decisão em relação a estratégias de manejo ambiental, seleção genética de indivíduos termotolerantes e incremento do bem-estar animal. Por fim, o uso de sistemas silvipastoris pode auxiliar na oferta de maior conforto térmico, que é uma condição que impacta diretamente na produtividade de bubalinos de leite e carne, quando estes são criados em regiões tropicais, como na Amazônia Oriental.

Evaluation of the thermoregulatory response of goats naturally exposed to the tropical climate using longitudinal data / Avaliação da resposta termorregulatória de cabras expostas naturalmente ao clima tropical a partir do uso de dados longitudinais

Rectal temperature (RT), heart rate (HR), and respiratory rate (RR), determined as repeated measurements over time in female goats, were used to identify covariance matrices that best fit the data for residual modeling on these three traits. Then, based on this result, the goats' responses to heat were evaluated. Five matrices were found with convergence for the three traits. The Heterogeneous Compound Symmetry matrix showed a good fit for modeling the residual associated with RT, whereas the Heterogeneous Autoregressive matrix had a better fit for RR and HR, according to the Akaike Information Criteria (AIC), corrected AIC (AICc), and Schwarz Bayesian Information Criterion (BIC) used. After adjusting the residual data for these three traits, a mixed-model analysis was used to evaluate collection period (3), physiological stage (3), and animal age (3) as fixed effects. Residual modeling interfered differently with the p-value associated with the fixed effects studied. Collection period and interactions did not influence the variation in RT (P>0.761), which was within the standard range for goats in the tropics, while the physiological stage of the goats affected it (P<0.05). Rectal temperature, HR, and RR tend to show covariance structures that can be modeled using specific residual covariance matrices, that is, the heterogeneous compound symmetry matrix best suits RT data, whereas the heterogeneous autoregressive matrix is better suited for HR and RR, which are usually correlated. The goats of the evaluated breed maintain RT within the range of variation displayed by breeds adapted to a hot environment, regardless of their physiological condition. Variations occur in RR and HR, without, however, exceeding the normal range for goats. Pregnancy causes goats to raise their RR in the rainy season of the year in the region in order to maintain RT within the normal range for the species.(AU)

Utilizou-se a Temperatura retal (TR), Frequências cardíaca (FC) e respiratória (FR) aferidas como medidas repetidas no tempo em fêmeas caprinas, objetivando-se identificar matrizes de estruturas de covariância que melhor se ajustou aos dados para modelagem do resíduo nessas três características e, em seguida, avaliou-se a respostas de cabras ao calor, com base nesse resultado. Constatou-se cinco matrizes com convergência nas três características. A Simétrica composta heterogênea ajustou-se bem para modelagem do resíduo associado a TR, enquanto a Autorregressiva heterogênea ajustou-se melhor para a FR e FC, de acordo com os critérios de informação de Akaike (AIC), Akaike corrigido (AICc) e o Bayesiano de Schwarz (BIC) utilizados. Com o resíduos de dados dessas três características ajustados, utilizou-se uma análise com modelos mistos para avaliar a Época de coleta (3), Estado fisiológico (3) e Idade do animal (3) foram como efeitos fixos. Constatou-se que a modelagem do resíduo interferiu de modo diferenciado no p valor associado aos efeitos fixos estudados. A época da coleta e interações não influenciaram a variação da TR (P>0,761), que oscilou dentro da faixa padrão para caprinos nos trópicos, mas o Estágio fisiológico da cabra sim (P<0,05). A Temperatura retal e as Frequências cardíaca e respiratória tendem a apresentar estruturas de covariâncias modeláveis com utilização de matrizes de covariâncias residuais especificas, ou seja, a matriz Simétrica composta heterogênea mais adequada para dados da Temperatura retal, enquanto a Autorregressiva heterogênea para as Frequências cardíaca e respiratória, geralmente correlacionas. As cabras da raça avaliadas mantêm a temperatura retal dentro da amplitude de variação apresentada por raças adaptadas a ambiente quente. Isso ocorre independente da condição fisiológica que se encontra, mas com ocorrência de variação na frequência respiratória e cardíaca, não excedendo, no entanto, a faixa normal para caprinos. A gestação condiciona a cabra a elevar a FR na época chuvosa do ano na região para manter a TR na faixa de amplitude normal para caprinos.(AU)

Thermal comfort and photoperiod on the productive performance of sows and piglets / Conforto térmico e fotoperíodo sobre o desempenho produtivo de porcas e de leitões

Pigs have difficulty in performing heat exchange and; therefore, it is important to consider the environmental factors that impact their productive performance. This study evaluated the effect of thermal comfort and photoperiod on the productive performance of sows during pregnancy and of nursery piglets. Zootechnical data were obtained from a commercial farm. The temperature-humidity index (THI) was used as the parameter to determine comfort or thermal stress of the sow. The parameters of the sows during pregnancy and nursery piglets were analyzed considering the criteria of comfort, stress, and four photoperiods. The correlation between photoperiod and THI was high and positive, which demonstrated the associated effect of these variables. More significant effects were observed under conditions of comfort and shorter photoperiods. In conclusion, thermal comfort and photoperiod influenced the parameters evaluated during pregnancy and in the nursery, and the strong association between THI and photoperiod suggested that environmental control favors productive parameters in commercial farms.

Os suínos são animais que apresentam dificuldade em realizar trocas de calor, por esse motivo é importante considerar os fatores ambientais que impactam seu desempenho produtivo. O objetivo do presente trabalho foi avaliar o efeito do conforto térmico e do fotoperíodo, sobre o desempenho produtivo das porcas na gestação e leitões na maternidade. Os dados zootécnicos foram obtidos de uma granja comercial. O índice de temperatura e umidade (ITU) foi utilizado como parâmetro para o conforto ou o estresse térmico da matriz. Foram analisados os parâmetros das fêmeas no período gestacional e dos leitões na maternidade, considerando os critérios de conforto, estresse e quatro faixas de fotoperíodos. A correlação entre o fotoperíodo e ITU foi alta e positiva, demonstrando efeito associado dessas variáveis. Foram observados mais efeitos significativos em situações de conforto e faixas de menor fotoperíodo. Em conclusão, o conforto térmico e o fotoperíodo influenciaram os parâmetros avaliados na gestação e na maternidade e a alta associação ITU e fotoperíodo sugere que o controle ambiental pode favorecer parâmetros produtivos em granjas comerciais.

Oxidative activity of corpus luteum and ovarian parenchyma in Bos taurus indicus heifers

The aim of this study was to evaluate the oxidative stress in ovaries and corpus luteum (CL) of Bos taurus indicus females and the oxidant effect of CL in ovarian tissues in regions near, intermediate, or distant from it. Ovaries (n=12) of Nelore heifers (n=6) were collected from a slaughterhouse and fragmented. Experiment 1, each ovary was obtained from three fragments, resulting in 18 fragments of ovaries with CL (OV+CL) and another 18 fragments of ovaries without CL (OV-CL). Three fragments were generated from CL, totaling 18 CL fragments. In experiment 2, the ovarian fragments were removed from specific regions near, intermediate, or distant from the CL. All the fragments were placed in Eppendorf-type microtubes (1 mL), kept in a thermal container at 4 ºC, and then stored in a -80 ºC freezer for analysis of oxidative stress (TBARS and NBT) and antioxidant potential (FRAP and ABTS). In the antioxidant activity analysis, luteal tissues showed more antioxidant activity than ovarian tissue (FRAP = P < 0.0001; ABTS = P < 0.02). In the oxidative stress analysis, CL had lower levels of reactive oxygen species (ROS; TBARS = P < 0.03; NBT = P < 0.0001) than ovarian tissues. There was no difference in antioxidant activity and oxidative stress between the fragments obtained from different regions (OV+CL versus OV-CL; P > 0.05). The presence of CL in the ovaries of Bos taurus indicus females did not influence the oxidative stress or antioxidant potential of the gonad. Thus, the removal of ovarian fragments with or without the presence of CL indicates that biotechnologies such as in vitro follicle cultivation is possible.(AU)

Cooling of porcine semen in an extender supplemented with isoespintanol / Resfriamento de sêmen suíno em um diluente suplementado com isoespintanol

ABSTRACT: Spermatozoa experience oxidative, osmotic, chemical, and thermal stresses when cooled, which degrade the quality and fertilizing capacity of the cells. Adding antioxidants to the sperm extender mitigates these alterations. This study evaluated the effect of isoespintanol (ISO) on boar semen subjected to cooling. Fifteen ejaculates from five boars (Susscrofadomestica) were extended in Beltsville thawing solution (BTS) supplemented with 0 µM (control), 5 µM (ISO5), 10 µM (ISO10), 15 µM (ISO15), 20 µM (ISO20), 25 µM (ISO25), and 30 µM (ISO30) of ISO, which were then cooled for five days at 16 °C. Sperm kinetics, total motility (TM), and progressive motility (PM) were evaluated every 24 h using an IVOS computer-assisted sperm analysis (CASA) system. On day 1 and day 5 of cooling, a hypoosmotic test, spectrofluorometry, and flow cytometry were performed to evaluate the following: membrane functionality, measured as a function of hypoosmotic swelling (HOS); total antioxidant capacity (TAC); reactive oxygen species (ROS); and mitochondrial membrane potential (Δ¥M). Regression analysis and comparison of means using the Duncan test were performed. The ISO added had a slight impact on sperm motility, as evidenced by a reduction in TM at 24 h of cooling (but not prior) with the addition of 20 µM of ISO. Similarly, no effect of the ISO on the kinetics and functional integrity of the sperm membrane was observed at 96 h of cooling; however, the regression coefficients indicated that the ISO lowered the rate of decrease in sperm motility and the proportion of rapid spermatozoa relative to the concentration of ISO used. The ISO did not affect the TAC of the cooled semen; however, different concentrations of ISO lowered ROS production in the semen after 96 h of cooling. ISO also impacted the Δ¥M of the spermatozoa at 0 h of cooling, increasing the proportion of low Δ¥M cells and decreasing the proportion of high Δ¥M cells. In conclusion, ISO can reduce the loss of quality and oxidative stress occurring in boar semen during cooling and can modulate the mitochondrial activity of sperm.

RESUMO: Durante a refrigeração, os espermatozoides sofrem estresse oxidativo, osmótico, químico e térmico, que diminuem sua qualidade e afetam sua capacidade de fertilização. A adição de antioxidantes ao diluente espermático é uma alternativa para mitigar essas alterações. O objetivo desta pesquisa foi avaliar o efeito do isospintanol (ISO) na refrigeração do sêmen suíno. Quinze ejaculados de cinco varrascos (Sus scrofa domestica) foram diluídos em BTS suplementado com ISO a 0 (controle), 5 (ISO5), 10 (ISO10), 15 (ISO15), 20 (ISO20), 25 (ISO25) e 30 (ISO30) µM e foram refrigerados por cinco dias a 16 °C. A motilidade total (MT), motilidade progressiva (MP) e cinética dos espermatozóides foram avaliadas a cada 24 h com um sistema CASA IVOS. Nos dias um e cinco de refrigeração, foram avaliadas a funcionalidade da membrana, a capacidade antioxidante total (CAT), as espécies reativas de oxigênio (ROS) e o potencial de membrana mitocondrial (Δ¥M), através do teste hiposmótico (HOS), espectrofluorimetría e citometria de fluxo. Foram realizadas análises de regressão e comparação de médias, pelo teste de Duncan. A adição de ISO teve pouca influência na motilidade espermática, apresentando apenas redução na MT em 24 h de refrigeração, devido à adição de 20 µM. Da mesma forma, não foi observada influência de ISO na cinética e integridade funcional da membrana em 96 horas de refrigeração; porém, os coeficientes de regressão mostraram que ISO produziu menor taxa de diminuição da motilidade e proporção de espermatozoides rápidos dependendo da concentração utilizada. ISO não influenciou significativamente na CAT do sêmen refrigerado; entretanto, diferentes concentrações de ISO reduziram a produção de EROs a partir do sêmen após de 96 h de refrigeração. ISO também influenciou o Δ¥M dos espermatozóides em 0 h de refrigeração, com aumento das células de baixo Δ¥M e diminuição das células de alto Δ¥M. Em conclusão, o isospintanol pode reduzir a perda da qualidade e o estresse oxidativo do sêmen suíno durante a refrigeração e pode modular a atividade mitocondrial do esperma.

Lesão facial grave em um gambá-de-orelha-branca (Didelphis albiventris) - tratamento com ozonioterapia / Severe facial wound in a white-eared opossum (Didelphis albiventris) - treatment with ozone therapy

Background: Ozone therapy (OT) is a type of treatment that uses ozone gas, which has high oxidizing power. OT has been utilized for various diseases and to accelerate the wound healing process and reduce inflammation. Additionally, OT is a low-cost treatment recommended for patients that can be easily restrained. There are several methods of ozone administration, including topical use through bagging, cupping, or rectal insufflation, in addition to ozonated autohemotherapy. Based on the benefits of OT and the scarcity of reports describing its effects on white-eared opossums (Didelphis albiventris), we report on the use of ozone in the treatment of a severe facial wound in a white-eared opossum. Case: An adult female white-eared opossum weighing 1.6 kg was rescued from a fire. The patient was pregnant, dehydrated, hypothermic and had an extensive burn wound in the facial region. Due to the stress of captivity and its aggressive behavior, the animal needed to be chemically restrained with dexmedetomidine and butorphanol. Following sedation, the cephalic vein was catheterized and intravenous fluid therapy with ringer lactate was started to treat dehydration. Next, enrofloxacin, meloxicam, and tramadol hydrochloride were administered. Body rewarming was performed with thermal bags. The microbial load of the wound was reduced with chlorhexidine degerming solution followed by washing with saline solution. A thin layer of silver sulfadiazine cream was applied to the wound area. Over the following days the patient was treated with OT using the cupping technique combined with ozonated sunflower oil. After the first applications there was an improvement in the appearance of the wound, which initially had a purulent aspect. After 20 days of treatment the wound showed good granulation and there were no signs of infection, and at 45 days of treatment it was completely healed. The patient was then released with her baby. Discussion: Ozone therapy was included in the patient's treatment plan to enhance the tissue repair process in order to reintroduce the animal to the wild in the shortest possible time. The strategy was successful in improving healing and reducing tissue inflammation and infection. Ozone is known to cause the inactivation of microorganisms as a result of the oxidation of phospholipids and lipoproteins present in the cell membrane of bacteria and to interrupt viral replication. Ozone helps in the perfusion of injured tissues, contributing to the entry of humoral components, which control inflammation. Moreover, ozone contributes to increase supply of oxygen and nutrients to tissues and to stimulate increased production of fibrinogen and formation of granulation tissue. Ozone increases the enzymatic antioxidant response, while also playing a role in immunoregulation. Ozone can be used in several ways and via various methods with potential routes including intravenous, urethral, intramuscular, subcutaneous, or intra-articular, in addition to rectal and intramammary insufflation. Immunomodulatory, anti-inflammatory, analgesic, and antiseptic effects can be achieved with different doses and concentrations, which enables its application in different types of pathologies. Because of the aggressive behavior of the animal, in the current case we opted for the cupping technique combined with ozonated oil, both techniques which can be administered easily with only physical restraint of the patient. Cupping allows for the provision of a higher concentration of ozone gas locally whereas the ozonated oil maintains the effect of the gas for slightly longer, enhancing its effect and promoting tissue repair. The present report showed that OT is an effective alternative for the treatment of burn wounds in opossums, without causing adverse effects to the patient or her baby.

Uso da termografia e ultrassonografia power dopplerpara avaliação da resposta tecidual em falhas ósseas preenchidas com biomaterial em ovinos / Termography and power doppler sonography assessment for tissue response evaluation in sheep bone defects filled with biomaterial

Biomateriaistem diversas indicações como auxiliares no processo de reparação óssea, além de terem função de substituto ósseo em perdas extensas. Diversas são as vantagens de sua utilização, como por exemplo, auxílio na osteocondutividade, estímulo de neovascularização, potencial antimicrobiano, entre outros. Falhas ósseas foram realizadas nas tíbias de seis ovinos da raça Santa Inês e preenchidas com biomaterial à base de quitosana, colágeno e hidroxiapatita. Um membro foi considerado controle e outro membro tratado segundo estudo randomizado. Foram realizadas avaliações termográficas e por ultrassonografia Power Dopplerem todos os animais do estudo, semanalmente, nos dias D0, D7, D14, D21, D28, D35, D42 e D56. Não houve diferenças significativas com relação à temperatura mínima, máxima e média entre os grupos com biomaterial e controle nas imagens termográficas. Houveram variações com relação ao tempo dentro de ambos os grupos. Com relação à presença de vasos na ultrassonografia Power Dopplernão houve diferenças estatísticas entre os grupos, exceto no dia 21 (P=0,031). Dentro das possibilidades de avaliação que os exames de imagem fornecem, a termografia e a ultrassonografia Power Dopplermostraram-se ferramentas não invasivas de avaliação pós-operatória de processo inflamatório e neovascularização, sendo realizadas semanalmente, permitindo acompanhamento fidedigno e detalhado ao longo do experimento, sem gerar desconforto ou estresse aos animais. Não houve indícios de complicações relacionadas ao biomaterial.(AU)

Biomaterials have several indications supporting the bone repair process, besides having bone substitute function in extensive losses. There are several advantages of its use, such as contribution in osteoconductivity, stimulation of neovascularization, antimicrobial potential, among others.Tibial bone defects was performed in six Santa Inês breed ewes and implanted with chitosan, collagen and hydroxyapatite biomaterial. One limb was considered the control limb and the other one the biomateriallimb, chosenrandomly. Thermographic and Power Dopplersonography was performed in all animals, weekly for 56 days. The thermography showed no significant differences related to low, high and mean temperature between the control and the biomaterial groups. Statisticalvariations were found between time in both groups. The visualization of neovascularization with the Power Dopplersonography did not present statistical differences, except for day 21 (P=0,031). Within the possibilities provided by imaging exams, thermography and Power Doppler sonography demonstrate to be non-invasive methods for post-operative evaluation of inflammatory process and neovascularization. The weekly management allowed reliable and detailed monitoring throughout the experiment, without causingdiscomfort or stress to the animals. There was no evidence of biomaterial complications.(AU)

Molecular investigations of the effect of thermal manipulation during embryogenesis on muscle heat shock protein 70 and thermotolerance in broiler chickens

The objective of this study was to elucidate the optimum protocol timing of thermal manipulation (TM) during embryogenesis, which underline genetic improvement of muscle thermotolerance acquisition. For the present study, 1,440 fertile eggs were divided randomly and equally into control (37.8 °C with 56% relative humidity) and four thermally manipulated groups (TM1, TM2, TM3, and TM4) subjected to 39 °C for 18 h with 65% relative humidity daily during different embryonic periods. Then, at day 35 post-hatch, all groups were subjected to thermal challenge at 43 °C for 6 h to identify the level of thermotolerance acquisition differences between them. Hsp70 mRNA expression was evaluated by using a relative quantitatively RT-qPCR. Single nucleotide polymorphisms sequence of the Hsp70 gene was evaluated by Sanger's sequencing method. Pectoral and thigh muscles samples were subjected to immunohistochemistry to detect Hsp70. Among TM conditions that were investigated, TM1 (39 °C for 18 h during embryonic days (ED) 7­11) induced a significant improvement in thermotolerance parameters (body temperature and T3 levels) during thermal challenge combined with an increase in the levels of Hsp70 mRNA and its protein with a high stability of nucleotide sequences in both pectoral and thigh muscles. The partial DNA sequence of Hsp70 gene in TM1 was reported, and nucleotide sequences were deposited in NCBI GenBank database with the accession numbers (MK852579) and (MK852580). Thigh muscle thermotolerance acquisition was higher than pectoral muscle during thermal challenge at 43 °C for 6 h. Thus, TM during ED7­11 may improve thermotolerance acquisition without adversely affecting performance.(AU)

Magnesium in the water of Japanese quails kept under comfort zone and under thermal stress / Magnésio na água de codornas japonesas mantidas em zona de conforto e sob estresse térmico

The objective was to evaluate the increasing levels of magnesium in the water supplied to laying quails (Coturnix coturnix japonica), kept in climatic chambers under thermoneutral temperature and thermal stress, on their performance and morphometry of their organs. The birds were distributed in a completely randomized design, 2x4 factorial arrangement, 2 temperatures (24 and 32 ºC) and 4 levels of magnesium in the water (50, 150, 250 and 350 mg L-1), with six replicates and eight birds per experimental unit. The data were subjected to analysis of variance and the means compared by the Tukey test at 5% probability level. The magnesium levels in the water did not affect (P > 0.05) the production performance and morphometry of the organs, with less water consumption at the magnesium level of 150 mg L-1, and birds kept at 32 °C had a reduction in feed consumption and feed conversion, but without affecting organ morphometry. Japanese quails in the production phase can consume water with magnesium levels up to 350 mg L-1 without having their production performance and morphometry of organs affected and raised in an environment with temperatures of up to 32 °C.(AU)

O objetivo foi avaliar os níveis crescentes de magnésio na água fornecida a codornas (Coturnix coturnix japonica) em postura, mantidas em câmaras climáticas sob temperatura termoneutra e estresse térmico, sobre o desempenho e morfometria dos órgãos das aves. As aves foram distribuídas em delineamento inteiramente casualizado, arranjo fatorial 2x4, 2 temperaturas (24 e 32 ºC) e 4 níveis de magnésio na água (50, 150, 250 e 350 mg L-1), com seis repetições e oito aves por unidade experimental e os dados submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Os níveis de magnésio na água não afetaram (P > 0,05) o desempenho produtivo e a morfometria dos órgãos, com menor consumo de água ao nível de 150 mg L-1 de magnésio e, as aves mantidas a 32 °C tiveram uma redução no consumo de ração e conversão alimentar, mas sem afetar a morfometria dos órgãos. Codornas japonesas em fase de produção podem consumir água com níveis de magnésio de até 350 mg L-1 sem ter o desempenho produtivo e a morfometria dos órgãos afetados e criados em ambiente com temperatura de até 32 °C.(AU)

Interactive effects of digestible protein levels on thermal and physical stress responses in Nile tilapia

The effects of dietary digestible protein (DP) levels (22, 26, 29, 32, and 34%) and different stressors (cold-induced stress, CIS; heat/dissolved oxygen-induced stress, HDOIS; transport-induced stress, TIS; and size-sorting-induced stress, SSIS) on hemato-biochemical parameters were evaluated. Four hundred and forty Nile tilapia fingerlings were distributed into 40-250 L aquaria and fed experimental diets for 110 days, and fed each of the five experimental diets, that were randomly distributed to eight replicates per treatment. Then, different groups of fish were subjected to one type of stress. Groups of 40 fish were used on CIS (17 °C), HDOIS (32 °C), and TIS (4 h), and a group of 140 fish on SSIS (15 min air exposure and 60 s handling). There was no effect on hemato-biochemical profile when DP levels were compared, neither before nor after stress; however, there was a significant stress effect. Digestible protein did not mitigate stress response under SSIS and CIS; lymphopenia and neutrophilia were the main cell-mediated immune response; dietary 22 and 26% DP impaired oxygenation on SSIS and TIS; fish under HDOIS and SSIS demanded more energy using triglycerides as an energy source; the diet formulated to contain 22% DP was not adequate to keep homeostasis under temperature stress. Cluster analysis showed that, for DP levels below the requirement for growth, SSIS and CIS were considered the most stressful conditions. At 34% DP level, HDOIS response was comparable to that of non-stressing conditions.(AU)

Effects of thermal environment on dairy cattle under a grazing system in the Western Amazon, Brazil / Efeitos do ambiente térmico em bovinos leiteiros em sistema de pastejo na Amazônia Ocidental, Brasil

This study aimed to evaluate the thermal conditions to which animals are exposed and their effect on the comfort/discomfort of dairy herds in a grazing system in the municipality of Sena Madureira, Acre State, Brazil. Eight farms and a total of 113 lactating crossbred cows were evaluated. Dry-bulb temperature (DBT, °C), relative humidity (RH, %), black globe temperature (BGT, °C), and wind speed (v, km h¹) were measured in January, February, and March (rainy season) to calculate temperature-humidity index (THI), black globe-humidity index (GTWBI), and radiant heat load (RHL). Moreover, the animals were measured for the physiological variables: rectal temperature (RT), heart rate (HR), and respiratory rate (RR). Significant differences (P<0.05) were observed for THI, GTWBI, and RHL. THI reached a mean value of 80 on farm G in January. Farm F had a GTWBI value of 79 in February. RHL reached the highest value (510 W m²). RT and HR showed no differences among the analyzed months. Thus, the environmental conditions in which dairy cows are housed at milking time rarely promoted thermal discomfort, with farm G being the most affected by THI.

Objetivou-se avaliar as condições térmicas a que os animais estão submetidos, seu efeito no conforto/desconforto de rebanhos leiteiros em sistema de pastejo, no município de Sena Madureira-Acre. Foram avaliadas oito propriedades e o total de 113 vacas mestiças em lactação. As medições ocorreram nos meses: janeiro, fevereiro e março (inverno amazônico), mensurando-se: temperatura do bulbo seco (TBS, °C), umidade relativa do ar (UR, %) e temperatura de globo negro (TGN, °C), velocidade do vento (v, km/h) para cálculos dos índices da temperatura e umidade (ITU), índice da temperatura de globo e umidade (ITGU) e carga térmica radiante (CTR), além da temperatura retal (TR), frequência cardíaca (FC), frequência respiratória (FR). Entre as propriedades analisadas, houve diferenças significativas (P<0,05) para ITU, ITGU e CTR. Destaca-se que o ITU na propriedade G, em janeiro, atingiu o valor médio de 80. A propriedade F, em fevereiro, teve valor de 79 para o ITGU. A CTR apresentou carga elevada (510 W.m³). A TR e a FC não apresentaram diferença entre os meses analisados. Concluiu-se que o ambiente ao qual as vacas leiteiras estão alojadas na hora da ordenha encontraram-se poucas vezes em situação de desconforto térmico, sendo a propriedade, a mais afetada pelo ITU.

Simple physiological indicators of ½ Santa Inês × ½ Dorper crossbred sheep raised in the municipality of Mirador, Maranhão, Brazil / Indicadores fisiológicos simples de ovinos mestiços 1/2 Santa Inês X 1/2 Dorper criados no município de Mirador, Maranhão, Brasil

In this study we aimed to evaluate the influence of environmental differences caused by day shifts on the physiological indicators of crossbred ½ Santa Inês × ½ Dorper sheep raised in a semi-intensive system. For this, 12 animals with an average weight of 35.00 ± 5.00 kg were allocated in a completely randomized design, with two treatments (morning shift and afternoon shift) and six replicates per treatment. The environmental variables (temperature (ºC) and relative humidity (%)) were collected using a digital thermo-hygrometer. The black globe temperature and humidity index was calculated using temperature values of the black globe thermometer and dew point. The following physiological indicators were measured in the animals: respiratory rate (mov/min); heart rate (beats/min); rectal temperature (ºC); and surface temperature (ºC). In the morning shift, the average values of air temperature and relative humidity were 31.71ºC and 88.66%, respectively. In the afternoon, the average air temperature was 33.91ºC, while the relative humidity was 62.66%. The highest mean globe temperature and humidity index was observed in the afternoon shift (87.75). The physiological indicators showed the highest mean values in the afternoon shift: respiratory rate 73.72 mov/min; heart rate 81.27 beats/min; rectal temperature 39.98ºC; surface temperature 34.76ºC. The crossbred ½ Santa Inês × ½ Dorper sheep reared in a semi-intensive system showed signs of thermal discomfort.

Objetivou-se com esta pesquisa avaliar a influência das diferenças ambientais proporcionadas pelos turnos do dia sobre os indicadores fisiológicos de ovinos mestiços ½Santa Inês × ½Dorper criados em sistema semi-intensivo. Para isso, foram utilizados 12 animais, com peso médio de 35,00 ± 5,00 Kg, alocados em delineamento inteiramente casualizado, com dois tratamentos (turno manhã e turno tarde) e seis repetições por tratamento. As variáveis ambientais, temperatura (ºC) e umidade relativa do ar (%), foram coletadas com o uso de um termo-higrômetro digital. O índice de temperatura de globo negro e umidade foi calculado usando os valores da temperatura do termômetro de globo negro e do ponto de orvalho. Os indicadores fisiológicos mensurados nos animais foram às frequências, respiratória (mov./min.) e cardíaca (bat./min.), a temperatura retal (ºC) e a temperatura superficial (ºC). As médias para temperatura do ar foram, respectivamente, 31,71ºC e 33,91ºC para os turnos manhã e tarde, enquanto que a umidade relativa do ar foi de 88,66% e 62,66%, nessa mesma ordem. A média para o índice de temperatura de globo e umidade foi superior no turno tarde, com valor igual a 87,75. Os indicadores fisiológicos apresentaram maiores médias para o turno tarde, apresentando valores de 73,72 mov./min., 81,27 bat./min., 39,98ºC e 34,76ºC para frequência respiratória, frequência cardíaca, temperatura retal e temperatura superficial, respectivamente. Os ovinos mestiços ½Santa Inês x ½Dorper criados em sistema semi-intensivo apresentaram sinais de desconforto término.