Abstract In Compost-Bedded Pack Barn (CBP) systems, air velocity is linked with the thermal comfort of housed dairy cattle and bedding quality and, therefore, assessing ventilation efficiency is essential. In this context, the objective of this study was to evaluate and characterize dependence and spatial distribution of air velocity at the 1.5 m height (vair,M) and at bedding level (vair,B) in an open CBP system with positive pressure ventilation. The study was conducted in 2021, in a facility located in the Zona da Mata region, Minas Gerais, Brazil. The facility area was divided into a mesh composed of 55 equidistant points, where vair,M and vair,B data were collected in the morning (09:00 a.m.) and afternoon (03:00 p.m.) periods, during three weeks in Brazilian winter. Geostatistics techniques were used to assess dependence and spatial distribution. In both periods evaluated, there were a strong occurrence of spatial dependence and non-uniform vair,M and vair,B distributions. The vair,M and vair,B values were lower than recommended (1.8 m∙s–1) in more than 65.0% of the area. Adequate ventilation levels were observed only in the first 20.0 m of the facility, from Southeast to Northwest, because of the fan lines present.

ABSTRACT Broilers during the first phase should be protected from cold stress, especially in the winter, cold nights and early mornings. To protect animals, poultry producers have used different strategies, including the use of multilayer of curtain, to increase the thermal insulation and reduce heat losses, also decreasing the permeability to the external air. In this context it is important to give special attention to the indoor air quality of poultry sheds as part of a production under animal welfare parameters. This study was conducted in the municipality of Barbacena, MG, in Brazil, and aimed to assess air quality at the level of the chickens and workers, specifically concentrations of ammonia, carbon dioxide and carbon monoxide, in a poultry house naturally ventilated during the first phase of life of broilers in the winter period, and the influence of insulation level with side curtains on concentrations of ammonia. During the first experimental week, ammonia levels exceed acceptable values, and statistical difference was found between the concentrations of ammonia for different insulation levels with side curtains.

RESUMEN Los pollos de engorde durante la primera fase deben estar protegidos del estrés por frio, especialmente en el inverno, noches y madrugadas frías. Para proteger a los animales, los avicultores han utilizado diferentes estrategias, entre ellas está el uso de varias capas de cortinas para aumentar el nivel de aislamiento térmico y disminuir las pérdidas de calor, disminuyendo también la permeabilidad con el aire externo. En este contexto, es importante dar especial atención a la calidad del aire interno de los galpones avícolas como parte de una producción bajo parámetros de bienestar animal. El presente estudio fue realizado en el municipio de Barbacena, MG, en Brasil, y tuvo como objetivo evaluar la calidad del aire al nivel de los pollos y los trabajadores, específicamente de las concentraciones de amoniaco, dióxido de carbono y monóxido de carbono, en un galpón avícola naturalmente ventilado durante la primera fase de vida de pollos de engorde en el período de inverno, y la influencia del nivel de aislamiento con cortinas laterales sobre las concentraciones de amoniaco. Durante la primera semana experimental, los niveles de amoniaco sobrepasaron los valores aceptables, y se encontró diferencia estadística entre las concentraciones de amoniaco para los diferentes niveles de aislamiento con cortinas laterales.

RESUMOObjetivou-se, com este trabalho monitorar, em tempo real, o ambiente térmico de um aviário de postura e realizar o mapeamento completo da distribuição das variáveis temperatura do ar, umidade relativa do ar e índice de temperatura e umidade no alojamento. O trabalho foi conduzido no mês de janeiro de 2013 em uma granja comercial de aves de postura, sistemas verticais, com seis andares de gaiolas. O aviário é totalmente automatizado possuindo 100.000 aves alojadas na densidade de 300 cm2 ave-1. A partir dos dados coletados foram determinadas as médias de temperatura e umidade relativa do ar para período diurno e noturno de diferentes posições na instalação. Os mapas térmicos resultantes demostram que ocorreu uma variabilidade térmica em diferentes posições espaciais no interior do aviário, com a região central apresentando temperaturas superiores às das extremidades porém dentro da faixa de conforto térmico das aves considerando a situação de temperaturas médias, durante calor extremo a temperatura interna na instalação alcançou 33 oC. A umidade relativa do ar apresentou pequenas variações durante o dia e maiores no período da noite. Em relação ao índice de temperatura e umidade a maior parte da instalação permaneceu dentro da faixa de conforto.

ABSTRACTThe objective of this work was to monitor, in real time, the thermal environment of an avian posture and to perform a complete mapping of the distribution of the variables air temperature, relative humidity and temperature and humidity index in the housing. The study was conducted in January 2013 in a commercial farm of laying hens, vertical systems, with six floors of cage. The aviary is fully automated, having 100.000 birds housed in density of 300 cm2 bird-1. The collected data were analysed for the average temperature and relative humidity during day and nighttime and for different positions at the facility. The resulting thermal maps show that there was a temperature variation at different spatial positions within the poultry house, the central region having higher temperature in comparison to border but within the range of thermal comfort of the birds, considering the situation of average temperatures during extreme heat the internal temperature reached 33 oC in the installation. The relative humidity showed little variation during the day and highest in the evening. Regarding the temperature and moisture content, the greater part of the plant remained within the comfort range.

Na busca por respostas quanto às condições de bem-estar animal, visou-se a avaliar neste trabalho o comportamento de pintainhos nas duas primeiras semanas de vida, por meio de processamento de imagens digitais. O experimento foi realizado em dois galpões comerciais, utilizados para criação de 15.200 aves de corte por galpão, durante um ciclo produtivo, dotados com fornalha a lenha de aquecimento indireto do ar. Foram instaladas duas câmeras de vídeo por galpão para aquisição de imagens digitais. Uma das câmeras possuía inclinação angular de 45º, e a outra, inclinação angular de 90º em relação ao solo. As imagens foram analisadas para cada condição climática diária e binarizadas, sendo depois processadas por meio de descritor de agrupamento/dispersão e correlacionadas com os valores de temperatura do ar. Observou-se correlação entre o descritor e os valores de temperatura do ar, sendo que as imagens obtidas pela câmera posicionada a 45º e divididas em 25 blocos, obtiveram maior correlação. Pelos dados obtidos, pode-se observar que o comportamento de agrupamento e dispersão dos pintainhos pode ser usado como indicador dos estados de conforto térmico e que o descritor se mostrou eficiente para esta quantificação.

The aim of this study was to evaluate the behavior of young chickens in the first two weeks of life through digital images processing, for the determination of the best condition of animal welfare. The experiment was accomplished at two buildings with furnace with indirect air heating, used for creation of 15,200 broiler chickens by building, during one single productive cycle. For the production of digital images, two video cameras were installed by building. One of the cameras had an inclination of 45º and the other a 90º in relation to the ground. The images were analyzed for each daily climatic condition. Then, they were binarized and processed through grouping/dispersion descriptor and correlated with the values of temperature of the air. Correlation was observed between the descriptor and the values of temperature of the air. Images obtained by the camera positioned at 45º had the highest correlation. From the data obtained can be observed that the grouping/dispersion and the behavior of the young chickens can be used as indicator of the states of thermal comfort and that the descriptor was efficient for the quantification.