Utilização de caneca de alumínio como material alternativo para temperatura de globo de Vernon / Use of aluminum mug as alternative material for Vernon globe temperature

Diversos estudos relacionados à viabilidade e eficiência do uso de materiais alternativos ao globo de Vernon têm sido realizados, principalmente em decorrência ao preço elevado do cobre, componente do instrumento padrão. O objetivo foi avaliar a eficiência da utilização de caneca de alumínio como material alternativo para substituição do globo de Vernon. Para a confecção do protótipo empregou-se uma caneca de alumínio, utilizada em pistola de pintura, com capacidade de 50 ml. A caneca foi pintada com tinta preto-fosca, em duas camadas e um termômetro de mercúrio foi inserido ao centro. Para realização dos testes foram utilizados quatro equipamentos (dois globos de Vernon e dois globos negros alternativos). Foram efetuados testes prévios de comportamento temporal. Estabelecido o tempo, as temperaturas dos globos foram coletadas durante sete dias consecutivos, em três períodos, de 15 minutos cada. Os registros de temperatura foram realizados a cada cinco minutos, num total de 84 por equipamento. Os dados foram submetidos a análise de correlação de Pearson. Os resultados indicaram correlação positiva com o r2 de 0,9927, estabelecendo uma forte correlação entre os resultados de temperatura média do globo negro alternativo e globo de Vernon. Conclui-se que o globo negro alternativo do tipo caneca de alumínio mostrou-se eficiente para aferição da temperatura de globo negro em estudos de ambiência em substituição ao Globo de Vernon.(AU)

Several studies related to the feasibility and efficiency of using alternative materials to Vernon's globe have been carried out, mainly due to the high price of copper, a component of the standard instrument. The objective was to evaluate the efficiency of using an aluminum mug as an alternative material for replacing Vernon's globe. To make the prototype, an aluminum mug was used, used in a paint gun, with a capacity of 50 ml. The mug was painted with matte black paint, in two layers and a mercury thermometer was inserted in the center. Four pieces of equipment were used to carry out the tests (two Vernon globes and two alternative black globes). Previous temporal behavior tests were carried out. Once the time was established, the globes' temperatures were collected for seven consecutive days, in three periods of 15 minutes each. Temperature records were taken every five minutes, a total of 84 per equipment. Data were subjected to Pearson's correlation analysis. The results indicated a positive correlation with the r2 of 0.9927, establishing a strong correlation between the mean temperature results of the alternative black globe and Vernon's globe. It is concluded that the alternative black globe of the aluminum mug type proved tobe efficient for measuring the temperature of the black globe in ambience studies, replacing the Vernon Globe.(AU)

Agricultural tractor with different mass distributions between axles / Desempenho do trator agrícola com diferentes distribuições de massa entre eixos

ABSTRACT: An adjustment of the agricultural tractor is necessary to achieve energy efficiency, which can be done through the correct distribution of mass between the axles for each operating surface. This research evaluated different distributions of mass between axles in a 93 kW tractor equipped with auxiliary front-wheel drive, on two soil surfaces. The experiment was carried out in strip design, with a double factorial scheme (2 x 3), with two soil surfaces (mobilized and firm) and three mass distributions between axes (35/65%, 40/60% and 45/55%), with five repetitions, totaling 30 parcels. The slippage parameters of the front and rear wheelset, engine rotation, hourly and specific fuel consumption, force, power and yield on the drawbar, displacement speed, engine thermal efficiency, traction coefficient, rolling resistance, and yield in traction. On firm soil, the energy performance of the tractor was superior in relation to the mobilized one, which allowed greater tractor and drawbar performance with lower specific fuel consumption. The use of a 35/65% between-axle mass distribution provided maximum traction for the mechanized set, resulting from the reduction in energy expenditure generated by skating and; consequently, the maximum use of the energy made available by the mechanized set. However, the maximum conversion of energy contained in the working fuel is obtained with the 45/55% setting.

RESUMO: A assertiva adequação do trator agrícola é necessária para atingir máxima eficiência energética, podendo ser feita através da correta distribuição de massa entre eixos para cada superfície de operação. O objetivo deste trabalho foi avaliar diferentes distribuições de massa entre eixos em um trator de 93 kW equipado com tração dianteira auxiliar, em duas superfícies de solo. O experimento foi realizado em delineamento de faixas, com esquema fatorial duplo (2 x 3), sendo duas superfícies de solo (mobilizado e firme) e três distribuições de massa entre eixos (35/65%, 40/60% e 45/55%), com cinco repetições, totalizando 30 parcelas. Foram determinados os parâmetros de patinamento dos rodados dianteiros e traseiros, rotação do motor, consumo horário e específico de combustível, força, potência e rendimento na barra de tração, velocidade de deslocamento, eficiência térmica do motor, coeficiente de tração, resistência ao rolamento e rendimento em tração. Em solo firme, o desempenho energético do trator foi superior em relação ao mobilizado, o qual possibilitou maior rendimento tratoreo e na barra de tração com menor consumo específico de combustível. O uso da distribuição de massa entre eixo de 35/65% proporcionou a maximização na tração do conjunto motomecanizado, decorrente da redução do dispêndio energético gerado pelo patinamento e consequentemente o máximo aproveitamento da energia disponibilizada pelo conjunto mecanizado. Entretanto, a máxima conversão da energia contida no combustível em trabalho é obtida com a configuração 45/55%.

Agricultural tractor with different mass distributions between axles / Desempenho do trator agrícola com diferentes distribuições de massa entre eixos

An adjustment of the agricultural tractor is necessary to achieve energy efficiency, which can be done through the correct distribution of mass between the axles for each operating surface. This research evaluated different distributions of mass between axles in a 93 kW tractor equipped with auxiliary front-wheel drive, on two soil surfaces. The experiment was carried out in strip design, with a double factorial scheme (2 x 3), with two soil surfaces (mobilized and firm) and three mass distributions between axes (35/65%, 40/60% and 45/55%), with five repetitions, totaling 30 parcels. The slippage parameters of the front and rear wheelset, engine rotation, hourly and specific fuel consumption, force, power and yield on the drawbar, displacement speed, engine thermal efficiency, traction coefficient, rolling resistance, and yield in traction. On firm soil, the energy performance of the tractor was superior in relation to the mobilized one, which allowed greater tractor and drawbar performance with lower specific fuel consumption. The use of a 35/65% between-axle mass distribution provided maximum traction for the mechanized set, resulting from the reduction in energy expenditure generated by skating and; consequently, the maximum use of the energy made available by the mechanized set. However, the maximum conversion of energy contained in the working fuel is obtained with the 45/55% setting.

A assertiva adequação do trator agrícola é necessária para atingir máxima eficiência energética, podendo ser feita através da correta distribuição de massa entre eixos para cada superfície de operação. O objetivo deste trabalho foi avaliar diferentes distribuições de massa entre eixos em um trator de 93 kW equipado com tração dianteira auxiliar, em duas superfícies de solo. O experimento foi realizado em delineamento de faixas, com esquema fatorial duplo (2 x 3), sendo duas superfícies de solo (mobilizado e firme) e três distribuições de massa entre eixos (35/65%, 40/60% e 45/55%), com cinco repetições, totalizando 30 parcelas. Foram determinados os parâmetros de patinamento dos rodados dianteiros e traseiros, rotação do motor, consumo horário e específico de combustível, força, potência e rendimento na barra de tração, velocidade de deslocamento, eficiência térmica do motor, coeficiente de tração, resistência ao rolamento e rendimento em tração. Em solo firme, o desempenho energético do trator foi superior em relação ao mobilizado, o qual possibilitou maior rendimento tratoreo e na barra de tração com menor consumo específico de combustível. O uso da distribuição de massa entre eixo de 35/65% proporcionou a maximização na tração do conjunto motomecanizado, decorrente da redução do dispêndio energético gerado pelo patinamento e consequentemente o máximo aproveitamento da energia disponibilizada pelo conjunto mecanizado. Entretanto, a máxima conversão da energia contida no combustível em trabalho é obtida com a configuração 45/55%.

Drying of soybean seeds and effect on protein quality and oil extraction efficiency by extruding-expelling process

Soybean seeds (Glycine max) were dried under real scale conditions to different final moisture content (m.c.) (9.1, 9.7, 10.9 %, and control with 16.2 %) and processed through extruding-expelling. Results indicated that soybean seed m.c. affected the composition of the soybean expeller and, thus, the oil extraction efficiency (OEE), which increased as the seed m.c. decreased. A polynomic model was proposed for predicting OEE as a function of soybean m.c., indicating that drying soybean to 10 % resulted in an OEE of approximately 65 %. A thin layer drying experiment of soybean seeds indicated that the protein dispersibility index (PDI) was not affected as regards drying air temperatures up to approximately 69 °C, and a bi-linear model with a non-pre-established break point was fitted. The real scale drying treatment in a rack type dryer (mixed flow) did not show any effect (p > 0.05) on the PDI at 80 °C, while at 115 °C a reduction (p < 0.05) was observed (PDI reduction was 0.8 and 2.1 percentage points, respectively).(AU)

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)

Physical and environmental characteristics of the compost barn system and its effects on the physical integrity, reproduction and milk production of dairy cattle: a scoping review

Compost barn (CB), although recent in Brazil, is increasingly gaining popularity among the intensive breeding systems in the dairy sector. This system promises to offer several advantages to producers and animals: such as providing an environment in which milk production is increased and the physical integrity of cattle is improved, reducing mastitis episodes, and promoting thermal comfort for animals. Another factor that highlights CB concerning other intensive systems is the composting process, generated by the deposition of carbon-rich materials (bedding) with nitrogen sources (urine and feces) from animals. For the full benefits of this composting to be achieved, management, especially of bedding, must be carried out correctly, considering the development requirements of the compost, the use of quality organic material, adequate ventilation, and an ideal rate of animal capacity, so that the generation of heat occurs efficiently. However, there is a general lack of information about the CB system. Hence, there is an increasing need for data surveys of Brazilian regions to compare the diversity of materials used in bedding, assessing energy efficiency and performance over time. Therefore, this bibliographical review addressed the main points of the CB system approach, considering that studies such as this are consistently relevant for rural producers, facilitating decisions regarding the implementation and management of the CB system on their farms.

Thermal environment characterization of laying hen-housing systems

This study systematically collected data on variables that influence the thermal environment characteristics in poultry houses. Laying poultry farming is a relevant economic activity in Brazilian agriculture and has been expressively growing mainly regarding genetics and nutrition. Thermal comfort in poultry houses is needed to achieve poultry's maximum productive potential. Therefore, laying aviaries previously naturally ventilated (positive pressure) are starting to be equipped with cage batteries and designed with lateral closures, using negative pressure ventilation and in some cases associated with adiabatic cooling. However, negative pressure ventilation systems' thermal efficiency in tunnel mode and its distribution in different cage levels is still slightly known. Consequently, this system's thermal efficiency needs to be investigated to ensure adequate climate indices recommendations and avoid costs and losses due to inadequate handling and facilities.

Induction to tetraploidy in Pacific oysters (Crassostrea gigas)

As an alternative to the use of cytochalasin B(CB), 6-dimethylamino-purine (6-DMAP) and thermal shock (heat shock by increasing the temperature from 25 to 36ºC) could be used to induce tetraploidy in Pacific oyster (Crassostrea gigas) diploids. Induction was performed by applying shocks after elimination of the first polar corpuscle at the end of meiosis I. Ploidy rates were verified using flow cytometry. Tetraploid larvae were obtained using all inductor (6-DMAP, thermal shock and CB) treatments. No difference in the efficiency of tetraploidy induction was noted among 6-DMAP, thermal shock and CB. The number of D-larvae and their yield, determined by calculating the percentage of well-formed D-larvae in relation to the total number of larvae, was similar (p>0.05) among the evaluated induction methods. We suggest that 6-DMAP and thermal shock should be used in tetraploidy induction protocols, thereby avoiding the use of CB, which is a harmful agent for both humans and the environment.(AU)

Productive, physiological and behavioral sheep profiles housed on facilities with different roofs in the Amazon region

The Brazilian Amazon region is characterized by high rainfall, with high temperatures and relative humidity, where sheep are raised in extensive and semi-intensive systems and some regions. This work aimed to evaluate the climatic indices of sheepfolds in the Amazon region, the productive performance, and physiological variables of Santa Inês sheep confined in sheepfolds with fiber cement (FC) and polyvinyl chloride (PC) tiles. Twenty castrated males of Santa Inês sheep were used, with a mean age of 1.5±0.2 years old and a live weight of 23±2.1 kg. The statistical design used was a completely randomized design with two roofs (FC and PC). The temperature, relative humidity of the air, temperature index of the black globe, and thermal radiation load was above the comfort zone for sheep, being higher (P < 0.05) in the sheepfold with PVC tile than FC, which contributed to the increase in respiratory rate, as a way to maintain the animals' homeotherm. Furthermore, sheep installed in the sheepfold with FC tile showed the highest weight gain, spent more time feeding, increased feeding efficiency, dry matter and fiber intake, reducing daily water intake.

Evaluation of environmental parameters in a microregion in southern Amazonas State, Brazil, and their relationship with heat stress in dairy cattle / Avaliação de parâmetros ambientais em uma microrregião no sul do estado do Amazonas e suas relações com estresse térmico de bovinos leiteiros

Environmental thermal comfort provides higher efficiency in the exploitation of dairy farming, as the responses of animals to the environment are decisive in the activity's success. This study aimed to evaluate heat stress in dairy cows in the municipality of Humaitá, located in the south of theAmazonas State (AM), Brazil.Air temperature (TA) and relative humidity (RH) data were used to calculate the temperature humidity index (THI) in the dry (August 2020) and rainy seasons (January 2021). The August data were collected at the automatic weather station belonging to the National Institute of Meteorology. The January data were collected by a Hobo® U23-001 thermo-hygrometer installed at Fazenda Nossa Senhora Aparecida. The hourly and monthly means of the data were calculated and, subsequently, boxplots were plotted. TA and RH were 0.65 °C and 0.64% below the provisional climatological normal (PCN), respectively, for August, while January presented 0.77 °C and 3.61% above the PCN, respectively. THI values ranged from 56.25 (comfortable) to 84.68 (emergency) in August and 74.15 (comfortable) to 84.07 (emergency) in January. The maximum THI was observed in August, as well as the largest range. The results allow inferring that heat stress in dairy cows in the municipality of Humaitá-AM presents a state of alert even for cross-breed animals. Thus, the use of shading in pastures is suggested to minimize the effect of heat stress on the productive performance of the animals.(AU)

O conforto térmico ambiental proporciona uma maior eficiência na exploração da pecuária leiteira, pois as respostas do animal ao ambiente são determinantes no sucesso da atividade. O objetivo deste trabalho foi avaliar o estresse térmico em vacas leiteiras no município de Humaitá, localizado no sul do estado do Amazonas (AM), Brasil. Foram utilizados dados de temperatura do ar (TA) e umidade relativa do ar (UR) para cálculo do Índice de Temperatura e Umidade (ITU) na estação seca (agosto de 2020) e na estação chuvosa (janeiro de 2021). Para o mês de agosto os dados foram coletados na estação meteorológica automática pertencente ao Instituto Nacional de Meteorologia. Em janeiro os dados foram coletados com o Termo-higrômetro (Hobo®, modelo U23-001) instalado na Fazenda Nossa Senhora Aparecida. As médias horárias e mensais dos dados foram feitas e, posteriormente, plotados gráficos boxplots. Os dados coletados para os meses do estudo apresentaram a TAe UR para o mês de agosto 0,65ºC e 0,64% abaixo da Normal Climatológica Provisória (NCP), respectivamente. Por outro lado, janeiro apresentou 0,77ºC e 3,61% acima da NCP, respectivamente. Os ITUs variaram entre 56,25 (confortável) e 84,68 (emergência), em agosto e de 74,15 (confortável) a 84,07 (emergência) em janeiro. O máximo ITU foi observado em agosto, bem como a maior amplitude. Baseados nos resultados encontrados pode-se aferir que o estresse térmico em vacas leiteiras no município de Humaitá-AM apresenta estado de alerta, mesmo para animais de raças cruzadas. Assim, sugere-se o uso de sombreamento nas pastagens para minimizar o efeito do estresse térmico no desempenho produtivo destes animais.(AU)

Thermal Response of Three Strains of Hens Housed in a Cage-Free Aviary at the Amazon Rainforest

This study aimed to evaluate the thermal response of three strains of hens housed in a cage-free system at the Amazon rainforest in order to evaluate how feather coverage influences thermal exchange with the environment. The experimental method was completely randomized and treatments comprised three strains of hens (Rhode Island Red (red feathers with feathers on the neck), alternative strain FCI (red feathers without feathers on the neck), and alternative strain FCIII (white feathers without feathers on the neck)), with 20 hens (replicates) analyzed per strain. Thermal images of each bird were captured in order to record the birds surface temperatures on five points in five targets. All data collected in this study were subjected to ANOVA and subsequently to the Tukey test at p≤0.01 and p≤0.05. The aviarys left wall presented a lower average temperature, indicating lower heat accumulation, while the floor presented higher heat accumulation. FCIII hens (white feathers) presented higher (p<0.05) heat accumulation on the head and legs, and lower (p<0.05) heat accumulation on the neck and back in relation to other analyzed hens, indicating increased heat exchange efficiency and high concentration of this process in specific body areas. FCI and FCIII hens (without feathers on the neck) presented lower (p<0.05) heat accumulation on the neck and higher (p<0.05) heat accumulation on the head and legs, indicating that the feather coverage directly influenced heat exchange mechanisms, and an increased area without feathers provided great heat exchange zones for birds in a tropical climate.(AU)

Thermal Response of Three Strains of Hens Housed in a Cage-Free Aviary at the Amazon Rainforest

This study aimed to evaluate the thermal response of three strains of hens housed in a cage-free system at the Amazon rainforest in order to evaluate how feather coverage influences thermal exchange with the environment. The experimental method was completely randomized and treatments comprised three strains of hens (Rhode Island Red (red feathers with feathers on the neck), alternative strain FCI (red feathers without feathers on the neck), and alternative strain FCIII (white feathers without feathers on the neck)), with 20 hens (replicates) analyzed per strain. Thermal images of each bird were captured in order to record the birds’ surface temperatures on five points in five targets. All data collected in this study were subjected to ANOVA and subsequently to the Tukey test at p≤0.01 and p≤0.05. The aviary’s left wall presented a lower average temperature, indicating lower heat accumulation, while the floor presented higher heat accumulation. FCIII hens (white feathers) presented higher (p<0.05) heat accumulation on the head and legs, and lower (p<0.05) heat accumulation on the neck and back in relation to other analyzed hens, indicating increased heat exchange efficiency and high concentration of this process in specific body areas. FCI and FCIII hens (without feathers on the neck) presented lower (p<0.05) heat accumulation on the neck and higher (p<0.05) heat accumulation on the head and legs, indicating that the feather coverage directly influenced heat exchange mechanisms, and an increased area without feathers provided great heat exchange zones for birds in a tropical climate.

Bactérias resistentes a antibióticos e o meio aquático: efeito na produção animal / Antibiotic resistant bacteria and the aquatic environment: Effect on animal production

O emprego de drogas antibióticas em larga escala tanto para fins profiláticos quanto para terapêuticos e agropecuários tem aumentado com o passar dos anos, passando a ser considerado um problema, devido à perda de eficiência desses medicamentos no combate a bactérias patogênicas. Assim, a pressão de seleção aplicada pelos antibióticos, que são utilizados em ambientes clínicos e agrícolas, tem promovido a evolução e disseminação de genes que conferem resistência a bactérias em escala mundial, independentemente de suas origens e nos mais variados tipos de sistemas ambientes. Antibióticos de origem urbana e agrícola persistem no solo e nos ambientes aquáticos, este último atuando como um importante reservatório de bactérias, facilitando a troca de material genético entre bactérias ambientais e patogênicas, e permitindo a disseminação de genes de resistência. Causando, assim, preocupação tanto para a medicina humana quanto para a veterinária, tendo em vista a diversidade de doenças causadas em humanos e animais domésticos por bactérias multirresistentes. Nesse contexto, o conhecimento dos mecanismos responsáveis pela transferência e aquisição de resistência com potencial para atingir animais de produção são de grande importância para o entendimento dos riscos associados à disseminação da resistência entre bactérias de diferentes ecossistemas à produção animal, possibilitando o conhecimento e desenvolvimento de estratégias para combater e minimizar seus efeitos.

The use of antibiotic drugs on a large scale for prophylactic, therapeutic and agricultural purposes has increased over the years, becoming a problem due to the loss of efficiency of these drugs in combating pathogenic bacteria. Therefore, the selection pressure applied by antibiotics that are used mainly in clinical and agricultural environments has promoted the evolution and dissemination of genes that confer resistance to bacteria worldwide, regardless of their origins and in the most varied types of environmental systems. Antibiotics of urban and agricultural origin persist in the soil and in aquatic environments, the latter, acting as an important reservoir of bacteria, facilitating the exchange of genetic material between the environment and pathogenic bacteria, and then, allowing the spread of resistance genes. Thus, causing concern for both human and veterinary health, due to the diversity diseases caused by multidrug resistant bacteria. In this context, knowledge of the mechanisms responsible for the transfer and acquisition of resistance with the potential to reach farm animals is of great importance for understanding the risks associated with the spread of resistance among bacteria from different ecosystems to animal production, enabling the knowledge and development of strategies to combat and minimize its effects.

Scrotal thermographic profile and seminal characteristics of Mangalarga Marchador stallions bred in the Atlantic Rainforest biome / [Perfil termográfico escrotal e características seminais de garanhões Mangalarga Marchador criados no bioma Mata Atlântica]

The objective of this study was to determine the scrotal thermographic profile and to verify the influence of temperature and humidity of the humid tropical climate on testicular temperature and seminal quality of Mangalarga Marchador stallions. The thermal profiles of the proximal, middle, and distal zones of the testicles and total surface temperature (TSTT) were recorded using an FLIR E60bx thermal imager. The average air temperature (°C) and relative humidity (%) were obtained 1, 5, 9, 33, and 66 days before semen collection and showed a mean value of 26.5±2.4 and 80.4±6.0 respectively. The scrotal surface temperature was close to 34°C and there was no variation with the age of the stallion, reproductive activity, and characteristics of the ejaculate (P>0.05). The only significant correlations obtained were between TSTT and minor defects (R = 0.41; P<0.05), between TSTT and total defects (R = 0.46; P<0.01), and between TSTT and percentage of morphologically normal sperm (R = -0.46; P<0.05). It was concluded that the Mangalarga Marchador stallions maintained the testicular temperature within favorable conditions for spermatogenesis, demonstrating the efficiency of testicular thermoregulation mechanisms in the Atlantic Forest biome.

O objetivo deste estudo foi determinar o perfil termográfico escrotal e verificar a influência da temperatura e da umidade do clima tropical úmido na temperatura testicular e na qualidade seminal de garanhões Mangalarga Marchador. Os perfis térmicos das zonas proximal, média e distal dos testículos e a temperatura da superfície total (TSTT) foram registrados usando-se um termovisor FLIR E60bx. A temperatura média do ar (° C) e a umidade relativa (%) foram obtidas um, cinco, nove, 33 e 66 dias antes da coleta de sêmen e apresentaram valor médio de 26,5 ± 2,4 e 80,4 ± 6,0, respectivamente. A temperatura da superfície escrotal foi próxima a 34°C, e não houve variação com a idade do garanhão, a atividade reprodutiva e as características do ejaculado (P>0,05). As únicas correlações significativas obtidas foram entre TSTT e defeitos menores (R=0,41; P<0,05), entre TSTT e defeitos totais (R=0,46; P<0,01), e entre TSTT e porcentagem de espermatozoides morfologicamente normais (R=-0,46; P<0,05). Concluiu-se que os garanhões Mangalarga Marchador mantiveram a temperatura testicular dentro de condições favoráveis para a espermatogênese, demonstrando a eficiência dos mecanismos de termorregulação testicular no bioma Mata Atlântica.

Impactos do estresse térmico na reprodução de fêmeas bovinas / Heat stress impact on bovine female reproduction

O estresse por calor (ET) ocorre quando a temperatura ambiente excede a zona de conforto térmico animal. Várias respostas corporais inespecíficas, capitaneadas pelos sistemas nervoso, neuroendócrino e imunológico são acionadas para manter a homeostase e resfriar o animal. O ET afeta o eixo hipotálamo-hipofisário-gonadal, comprometendo a liberação de gonadotrofinas, e promove o acúmulo de espécies reativas de oxigênio e proteínas anormais nas células ovarianas. Em resposta, as células ativam mecanismos antioxidantes e de reparação do DNA, que reduzem o metabolismo celular e aumentam as chances de sobrevivência; quando a reparação não é possível, acontece a apoptose. O ET impacta negativamente a produção de estradiol ovariano, o comportamento do estro, o desenvolvimento folicular, a competência dos oócitos e do embrião, as taxas de concepção, o estabelecimento e a manutenção da gravidez e até mesmo a eficiência reprodutiva da progênie. O combate ao ET inclui estratégias de combate ao aquecimento global progressivo e de manejo para resfriar os animais, e diminuir a produção de calor metabólico. O uso de biotecnologia reprodutiva e estratégias genéticas para gerar animais termotolerantes são também essenciais

Heat stress (HS), a harmful condition affecting animal production, reproduction, and welfare, occurs when an animal is exposed to temperatures that exceed its thermal comfort zone. Several nonspecific body responses involving neural, neuroendocrine, and immune systems are triggered to keep homeostasis in such conditions. These responses, primarily directed to cooling the body, also impact the hypothalamic-pituitary-gonadal axis, compromising the bovine female’s release of gonadotropins. Heat stress also promotes reactive oxygen species accumulation in ovarian cells, impairing protein folding and refolding, triggering antioxidant and DNA protection mechanisms. These mechanisms, directed to reduce cell metabolism and increase survival chances, are not always sufficient to protect the cell and result in apoptosis. Heat stress’s systemic and cellular consequences impact ovarian estradiol production, estrous behaviors, follicular development, oocytes and embryo competence, conception rates, pregnancy establishment and maintenance, and even the future reproductive efficiency of the progenies of cows exposed to HS during pregnancy. The combat of heat stress includes strategies to alleviate the effect of progressive global warming, management strategies to cool the animals, reduced metabolic heat, and methane production dietary approaches. The use of reproductive biotechs and genetic strategies to increase thermotolerant animals are also critical to overcoming the harmful effect of HS.

Analysis of different tracking intervals for parabolic trough collectors for water disinfestation in agricultural applications / Análise de diferentes intervalos de rastreamento de coletores solares parabólicos para desinfestação de água em aplicações agrícolas

The use of renewable energy is growing every year as an alternative to fossil fuel technology. Solar energy presents itself as a good alternative due to its great availability and energy potential. Solar thermal energy uses heat to warm fluids, and can also generate electricity, as well as being used in industrial processes and water desalination. The research and use of Parabolic Trough Collectors (PTCs) has been growing in recent years due to their ability to heat fluids at high temperatures in a relatively small area. In this work, two small PTCs were manufactured and tests were performed to improve the arrangements in order to increase the absorbed energy to reach temperature values for water disinfestation, aiming at the control of phytopathogens to control soil pathogens in small and medium farms. To control the automatic tracker, a low-cost system with Arduino, Light Dependent Resistors (LDRs) and step motors was used. The tracking times intervals analyzed were 1, 5 and 15 minutes. For the 1-minute tracking interval, the PTCs presented a thermal efficiency of 25.87%, with temperatures between 45 and 70 C and an average of 63.73 C. For the 5-minute tracking interval, the thermal efficiency was 18.48%, reaching temperatures between 41 and 68 ºC and an average of 57.9 ºC. For the 15-minute tracking interval, the PTCs presented a thermal efficiency of 14.80%, with temperatures between 39 and 62 °C and an average of 51.88 °C. The results showed that the tracking intervals of 1 and 5 minutes present more values between the lethal temperature range of 45 and 60 °C for phytopathogens. For agricultural application, the usage of a tracking interval of 5 minutes could be a good option for reducing the waste of system energy compared to the interval of 1 minute.

O uso de energia renovável está crescendo a cada ano como alternativa à tecnologia de combustíveis fósseis. A energia solar apresenta-se como uma boa alternativa devido à sua grande disponibilidade e potencial energético. A energia solar térmica utiliza o calor para aquecer os fluidos e também pode gerar eletricidade, bem como ser usada em processos industriais e dessalinização da água. A pesquisa e o uso de Coletores Solares Parabólicos (PTCs) têm crescido nos últimos anos devido à capacidade de aquecer fluidos em altas temperaturas em uma área relativamente pequena. Neste trabalho, dois pequenos PTCs foram fabricados, e testes foram realizados para melhorar os arranjos, a fim de aumentar a energia absorvida para atingir valores de temperatura para desinfestação de água, visando o controle de fitopatógenos no controle de patógenos de solo em pequenas e médias fazendas. Para controlar o rastreador automático foi utilizado um sistema de baixo custo com Arduino, Resistores de Potência Luminosa (LDRs) e motores de passo. Os intervalos de tempo de rastreamento analisados foram de 1, 5 e 15 minutos. Para o intervalo de rastreamento de 1 minuto, os PTCs apresentaram uma eficiência térmica de 25,87%, com temperaturas entre 45 e 70 ºC e 63,73 ºC de temperatura média. Para o intervalo de rastreamento de 5 minutos, a eficiência térmica foi de 18,48%, atingindo temperaturas entre 41 e 68 ° C e 57,9 ° C de temperatura média. Para o intervalo de rastreamento de 15 minutos, os PTCs apresentaram uma eficiência térmica de 14,80%, com temperaturas entre 39 e 62 ° C e 51,88 ° C de temperatura média. Os resultados mostraram que os intervalos de rastreamento de 1 e 5 minutos apresentam mais valores entre a faixa de temperatura letal de 45 e 60 ° C para fitopatógenos. Para aplicações agrícolas, o uso de um intervalo de rastreamento de 5 minutos poderia ser uma boa alternativa para uma redução no desperdício da energia do sistema em comparação com o intervalo de 1 minuto.

Analysis of different tracking intervals for parabolic trough collectors for water disinfestation in agricultural applications / Análise de diferentes intervalos de rastreamento de coletores solares parabólicos para desinfestação de água em aplicações agrícolas

The use of renewable energy is growing every year as an alternative to fossil fuel technology. Solar energy presents itself as a good alternative due to its great availability and energy potential. Solar thermal energy uses heat to warm fluids, and can also generate electricity, as well as being used in industrial processes and water desalination. The research and use of Parabolic Trough Collectors (PTCs) has been growing in recent years due to their ability to heat fluids at high temperatures in a relatively small area. In this work, two small PTCs were manufactured and tests were performed to improve the arrangements in order to increase the absorbed energy to reach temperature values for water disinfestation, aiming at the control of phytopathogens to control soil pathogens in small and medium farms. To control the automatic tracker, a low-cost system with Arduino, Light Dependent Resistors (LDRs) and step motors was used. The tracking times intervals analyzed were 1, 5 and 15 minutes. For the 1-minute tracking interval, the PTCs presented a thermal efficiency of 25.87%, with temperatures between 45 and 70 C and an average of 63.73 C. For the 5-minute tracking interval, the thermal efficiency was 18.48%, reaching temperatures between 41 and 68 ºC and an average of 57.9 ºC. For the 15-minute tracking interval, the PTCs presented a thermal efficiency of 14.80%, with temperatures between 39 and 62 °C and an average of 51.88 °C. The results showed that the tracking intervals of 1 and 5 minutes present more values between the lethal temperature range of 45 and 60 °C for phytopathogens. For agricultural application, the usage of a tracking interval of 5 minutes could be a good option for reducing the waste of system energy compared to the interval of 1 minute.(AU)

O uso de energia renovável está crescendo a cada ano como alternativa à tecnologia de combustíveis fósseis. A energia solar apresenta-se como uma boa alternativa devido à sua grande disponibilidade e potencial energético. A energia solar térmica utiliza o calor para aquecer os fluidos e também pode gerar eletricidade, bem como ser usada em processos industriais e dessalinização da água. A pesquisa e o uso de Coletores Solares Parabólicos (PTCs) têm crescido nos últimos anos devido à capacidade de aquecer fluidos em altas temperaturas em uma área relativamente pequena. Neste trabalho, dois pequenos PTCs foram fabricados, e testes foram realizados para melhorar os arranjos, a fim de aumentar a energia absorvida para atingir valores de temperatura para desinfestação de água, visando o controle de fitopatógenos no controle de patógenos de solo em pequenas e médias fazendas. Para controlar o rastreador automático foi utilizado um sistema de baixo custo com Arduino, Resistores de Potência Luminosa (LDRs) e motores de passo. Os intervalos de tempo de rastreamento analisados foram de 1, 5 e 15 minutos. Para o intervalo de rastreamento de 1 minuto, os PTCs apresentaram uma eficiência térmica de 25,87%, com temperaturas entre 45 e 70 ºC e 63,73 ºC de temperatura média. Para o intervalo de rastreamento de 5 minutos, a eficiência térmica foi de 18,48%, atingindo temperaturas entre 41 e 68 ° C e 57,9 ° C de temperatura média. Para o intervalo de rastreamento de 15 minutos, os PTCs apresentaram uma eficiência térmica de 14,80%, com temperaturas entre 39 e 62 ° C e 51,88 ° C de temperatura média. Os resultados mostraram que os intervalos de rastreamento de 1 e 5 minutos apresentam mais valores entre a faixa de temperatura letal de 45 e 60 ° C para fitopatógenos. Para aplicações agrícolas, o uso de um intervalo de rastreamento de 5 minutos poderia ser uma boa alternativa para uma redução no desperdício da energia do sistema em comparação com o intervalo de 1 minuto.(AU)

Canopy structure and morphogenesis of Italian ryegrass intercropped with red clover under cutting intervals determined by thermal sum / Estrutura do dossel e morfogênese do azevém anual consorciado com trevo vermelho em intervalos de corte determinados por soma térmica

The canopy structure and morphogenesis of ryegrass (Lolium multiflorum Lam.) was investigated after it was over seeded with Tifton 85 (Cynodon spp.) and intercropped with red clover (Trifolium pratense L.). Time intervals between cuts were determined by different thermal sums (125, 250, 375, and 500 degree-days [DD]). Cuts were conducted at a height equivalent to 50% of the average canopy height. Morphogenic and structural data were collected from July to October of 2016 and 2017, from a completely randomized block experimental design. Canopy height, extended tiller height, pseudostem length, and forage mass were fitted to linear equations according to the thermal sums. Interaction of ryegrass with red clover was the highest (12.1%) for longer cut intervals (375 and 500 DD). The leaf appearance rate (0.0080 leaf/DD), phyllochron value (128.8 DD), and senescence rate (0.10 cm/DD) of ryegrass were comparable between the different intervals. The slowest elongation rate (0.06 cm/DD) with the shortest interval duration between cuts (171.6 DD) was observed in the 125 DD interval. According to the findings from this 2-year experiment, the use of a 250 DD cut interval was recommended between grazing events, taking into account the efficiency of forage use, ryegrass leaf, stem ratio, and interactions with red clover in the canopy under rotational stocking.(AU)

A estrutura do dossel e a morfogênese do azevém (Lolium multiflorum Lam.) foram investigadas após a sobressemeadura em Tifton 85 (Cynodon spp.) e consorciado com trevo vermelho (Trifolium pratense L.). Os intervalos de tempo entre os cortes foram determinados por diferentes somas térmicas (125, 250, 375 e 500 graus-dia [GD]). Os cortes foram realizados a uma altura equivalente a 50% da altura média do dossel. Os dados morfogênicos e estruturais foram coletados no período de julho a outubro de 2016 e 2017, em um delineamento experimental de blocos ao acaso. A altura do dossel, a altura estendida do perfilho, o comprimento do pseudocolmo e a massa de forragem se ajustaram a equações lineares de acordo com a soma térmica. A consorciação de azevém e trevo vermelho foi maior (12,1%) para intervalos de corte mais longos (375 e 500 GD). A taxa de aparecimento foliar (0,0080 folha/GD), filocrono (128,8 GD) e a taxa de senescência (0,10 cm /GD) do azevém não foram diferentes entre os intervalos de corte. A menor taxa de elongação (0,06 cm/GD) e duração de elongação (171,6 GD) foi observada no menor intervalo entre cortes, 125 GD. De acordo com os achados deste experimento de dois anos, recomenda-se o uso de um intervalo de corte de 250 GD entre os eventos de pastejo, levando em consideração a eficiência do uso de forragem, proporção de folhas e colmo de azevém e trevo vermelho no dossel, sob lotação rotativa.(AU)

Lesions of the sheep reproductive system found in a slaughterhouse in the state of Bahia, Brazil / Lesões do sistema reprodutor em ovelhas de abatedouros frigoríficos no estado da Bahia

The present study aimed to evaluate and diagnose pathologies of the reproductive system of slaughtered sheep in slaughterhouses in the state of Bahia since there are few data on the subject as well as it is important to note the diagnosis of these diseases to apply appropriate control and prophylaxis measures. The research was carried out in slaughterhouses in the state of Bahia according to the "Serviço de Inspeção Federal" and "Serviço de Inspeção Estadual" for sheep slaughter. From July 2018 to February 2019, visits and monitoring of 1,072 slaughtered sheep were carried out. The animals came from 22 municipalities in the state of Bahia, aged from six to 18 months. During slaughter, the sheep reproductive systems were sectioned for evisceration and lesion collection. Additionally, epidemiological surveys related to origin, age, and race were obtained. For bacteriological examination, collections were performed with sterile scalpel slides and swabs in Stuart medium sterile tubes and refrigerated in a thermal box. For histopathological analysis, fragments were fixed in 10% formaldehyde and routinely processed for histology, stained with Hematoxylin and Eosin (HE). A study of the sheep's main pathological changes in slaughterhouses in the state of Bahia was carried out, in which 1.072 genital systems were evaluated, and 211 alterations were identified. The most affected reproductive organs were the ovaries (65.3%), followed by the uterus (29.4%) and uterine tubes (5.3%). In the ovaries, the most frequent lesion was a follicular cyst (34.1%); in the fallopian tubes, the cysts represented 3.3% of the lesions, and in the womb, endometritis was observed in 9% of the animals. Other pathologies identified in the ovaries were: luteinized cyst (2.3%); cystic granulosa cell tumor (0.5%); benign lesion (0.5%); agenesis unilateral (0.5%), in addition to other changes of little clinical significance, such as corpus luteum cysts (11.8%) and paraovarian cysts (15.6%). In the fallopian tubes, hydrosalpinx was observed (1%), as well as adenoma (0.5%), agenesis (0.5%), and cysts (3.3%). Uterine lesions included hydrometra (2.3%); Cystic Endometrial Hyperplasia (CEH), abscess, and pyometra (1.4% each); adenomyosis, womb sera petechiae, and total segmental aplasia (1% each); two pregnant uterus, in early pregnancy, presented pyometra (0.9%), however, no change was observed in the fetuses; and uterine polyp (0.5%). Ectopic pregnancy with fetal maceration (0.5%) was observed; vaginitis occurred in 0.5% of the animals, and endometrial melanosis in 8.5%. The high incidence of follicular cysts and endometritis are characterized as diseases that reduce the reproductive efficiency in herds, causing infertility and economic losses in production.(AU)

O objetivo do presente trabalho foi avaliar e diagnosticar alterações do sistema reprodutor de ovelhas abatidas em abatedouros frigoríficos no estado da Bahia. A pesquisa foi realizada em abatedouros frigoríficos do estado da Bahia com Serviços de Inspeção Federal e Estadual no abate de ovinos. No período de julho de 2018 a fevereiro de 2019 foram realizadas visitas e acompanhamento do abate de 1.072 ovelhas. Os animais eram provenientes de 22 municípios do estado da Bahia, com idade entre 6 a 18 meses. Durante o abate, na evisceração foram seccionados os sistemas reprodutores das ovelhas para avaliação e coleta das lesões. Adicionalmente foram obtidos inquéritos epidemiológicos relacionados à procedência, idade e raça. Para o exame bacteriológico, as coletas foram realizadas com lâminas de bisturi estéreis e swabs em tubos estéreis com meio Stuart e refrigeradas em caixa térmica. Para análise histopatológica, os fragmentos foram fixados em formol a 10% e processados de forma rotineira para histologia e corados pela hematoxilina e eosina (HE). Entre 1.072 sistemas genitais avaliados, identificou-se 211 alterações. Os órgãos do sistema reprodutor mais acometidos foram os ovários (65,3%), útero (29,4%) e tubas uterinas (5,3%). Nos ovários, a lesão mais frequente foi o cisto folicular (34,1%); no útero a endometrite (9%) e nas tubas uterinas, os cistos representaram (3,3%). Outras lesões identificadas nos ovários foram: cisto luteinizado (2,3%); tumor de células da granulosa (0,5%); adenoma (0,5%); agenesia unilateral (0,5%), além de outras alterações de pouco significado clínico, como cistos paraovarianos (15,6%) e corpo lúteo cístico (11,8%). Nas tubas uterinas observou-se, além dos cistos tubo-ovarianos (3,3%), hidrossalpinge (1%), adenoma (0,5%) e agenesia (0,5%). As lesões uterinas foram endometrite (9%), hidrometra (2,3%); hiperplasia endometrial cística, abscesso e piometra (1,4% cada); adenomiose, petéquias na serosa do útero e aplasia segmentar (1% cada); dois úteros gravídicos, em início de gestação, apresentaram piometra (0,9%), porém os fetos não apresentaram alterações; e pólipo uterino (0,5%). Observou-se uma gestação ectópica com maceração fetal (0,5%); a vaginite ocorreu em 0,5%, e melanose endometrial em 8,5%. Destaca-se a elevada incidência de cistos foliculares e endometrite que são doenças que reduzem a eficiência reprodutiva dos rebanhos, provocando infertilidade e perdas econômicas na produção.(AU)

Lesions of the sheep reproductive system found in a slaughterhouse in the state of Bahia, Brazil / Lesões do sistema reprodutor em ovelhas de abatedouros frigoríficos no estado da Bahia

The present study aimed to evaluate and diagnose pathologies of the reproductive system of slaughtered sheep in slaughterhouses in the state of Bahia since there are few data on the subject as well as it is important to note the diagnosis of these diseases to apply appropriate control and prophylaxis measures. The research was carried out in slaughterhouses in the state of Bahia according to the "Serviço de Inspeção Federal" and "Serviço de Inspeção Estadual" for sheep slaughter. From July 2018 to February 2019, visits and monitoring of 1,072 slaughtered sheep were carried out. The animals came from 22 municipalities in the state of Bahia, aged from six to 18 months. During slaughter, the sheep reproductive systems were sectioned for evisceration and lesion collection. Additionally, epidemiological surveys related to origin, age, and race were obtained. For bacteriological examination, collections were performed with sterile scalpel slides and swabs in Stuart medium sterile tubes and refrigerated in a thermal box. For histopathological analysis, fragments were fixed in 10% formaldehyde and routinely processed for histology, stained with Hematoxylin and Eosin (HE). A study of the sheep's main pathological changes in slaughterhouses in the state of Bahia was carried out, in which 1.072 genital systems were evaluated, and 211 alterations were identified. The most affected reproductive organs were the ovaries (65.3%), followed by the uterus (29.4%) and uterine tubes (5.3%). In the ovaries, the most frequent lesion was a follicular cyst (34.1%); in the fallopian tubes, the cysts represented 3.3% of the lesions, and in the womb, endometritis was observed in 9% of the animals. Other pathologies identified in the ovaries were: luteinized cyst (2.3%); cystic granulosa cell tumor (0.5%); benign lesion (0.5%); agenesis unilateral (0.5%), in addition to other changes of little clinical significance, such as corpus luteum cysts (11.8%) and paraovarian cysts (15.6%). In the fallopian tubes, hydrosalpinx was observed (1%), as well as adenoma (0.5%), agenesis (0.5%), and cysts (3.3%). Uterine lesions included hydrometra (2.3%); Cystic Endometrial Hyperplasia (CEH), abscess, and pyometra (1.4% each); adenomyosis, womb sera petechiae, and total segmental aplasia (1% each); two pregnant uterus, in early pregnancy, presented pyometra (0.9%), however, no change was observed in the fetuses; and uterine polyp (0.5%). Ectopic pregnancy with fetal maceration (0.5%) was observed; vaginitis occurred in 0.5% of the animals, and endometrial melanosis in 8.5%. The high incidence of follicular cysts and endometritis are characterized as diseases that reduce the reproductive efficiency in herds, causing infertility and economic losses in production.(AU)

O objetivo do presente trabalho foi avaliar e diagnosticar alterações do sistema reprodutor de ovelhas abatidas em abatedouros frigoríficos no estado da Bahia. A pesquisa foi realizada em abatedouros frigoríficos do estado da Bahia com Serviços de Inspeção Federal e Estadual no abate de ovinos. No período de julho de 2018 a fevereiro de 2019 foram realizadas visitas e acompanhamento do abate de 1.072 ovelhas. Os animais eram provenientes de 22 municípios do estado da Bahia, com idade entre 6 a 18 meses. Durante o abate, na evisceração foram seccionados os sistemas reprodutores das ovelhas para avaliação e coleta das lesões. Adicionalmente foram obtidos inquéritos epidemiológicos relacionados à procedência, idade e raça. Para o exame bacteriológico, as coletas foram realizadas com lâminas de bisturi estéreis e swabs em tubos estéreis com meio Stuart e refrigeradas em caixa térmica. Para análise histopatológica, os fragmentos foram fixados em formol a 10% e processados de forma rotineira para histologia e corados pela hematoxilina e eosina (HE). Entre 1.072 sistemas genitais avaliados, identificou-se 211 alterações. Os órgãos do sistema reprodutor mais acometidos foram os ovários (65,3%), útero (29,4%) e tubas uterinas (5,3%). Nos ovários, a lesão mais frequente foi o cisto folicular (34,1%); no útero a endometrite (9%) e nas tubas uterinas, os cistos representaram (3,3%). Outras lesões identificadas nos ovários foram: cisto luteinizado (2,3%); tumor de células da granulosa (0,5%); adenoma (0,5%); agenesia unilateral (0,5%), além de outras alterações de pouco significado clínico, como cistos paraovarianos (15,6%) e corpo lúteo cístico (11,8%). Nas tubas uterinas observou-se, além dos cistos tubo-ovarianos (3,3%), hidrossalpinge (1%), adenoma (0,5%) e agenesia (0,5%). As lesões uterinas foram endometrite (9%), hidrometra (2,3%); hiperplasia endometrial cística, abscesso e piometra (1,4% cada); adenomiose, petéquias na serosa do útero e aplasia segmentar (1% cada); dois úteros gravídicos, em início de gestação, apresentaram piometra (0,9%), porém os fetos não apresentaram alterações; e pólipo uterino (0,5%). Observou-se uma gestação ectópica com maceração fetal (0,5%); a vaginite ocorreu em 0,5%, e melanose endometrial em 8,5%. Destaca-se a elevada incidência de cistos foliculares e endometrite que são doenças que reduzem a eficiência reprodutiva dos rebanhos, provocando infertilidade e perdas econômicas na produção.(AU)