ABSTRACT The environment control of broiler houses must be done adequately to provide good thermal conditions to broilers without wasting energy. The objective of this study was to characterize the thermal environment in two mechanically ventilated broiler houses with a negative pressure ventilation system, one with a cellulose pad evaporative cooling system and the other with misting nozzles for evaporative cooling. The experiment was conducted in Ervália-MG during winter, spring, and summer. The thermal environment was characterized based on the relationship between the temperature observed inside the broiler houses and the temperatures recommended for the thermal comfort of birds of different ages. The recorded data were evaluated using descriptive statistics, and the spatial variation of the average temperature data recorded during the growth phase in both broiler houses was evaluated graphically using contour graphs. During the brooding phase, the temperatures recorded in both broiler houses were above the recommended values (27-30 °C; 24-27 °C; and 21-24 °C, for the 1st; 2nd and 3rd weeks of bird life respectively) during the entire evaluation period. In the growout phase, it was found that during winter and spring, the interior temperature was within the recommended range (15–27 °C), however, in summer, there were periods when the interior temperature was above the comfort range of birds.

Resumen La calidad del aire es un factor importante en la ganadería intensiva, ya que el aire es el principal vehículo para la difusión de agentes físicos, químicos y biológicos que afectan la salud y el bienestar de los animales y los humanos. El amoníaco es el principal gas contaminante generado en la producción avícola. En este estudio, se realizó una revisión de la literatura con el fin de resaltar cada etapa de transformación de nitrógeno en la producción avícola, explicando los mecanismos de conversión desde la ingestión de proteína cruda hasta la volatilización en la atmósfera como gas de amoníaco. En resumen, estos pasos son: síntesis de ácido úrico y excreción por las aves de corral; mineralización de nitrógeno presente en excretas; volatilización de amoniaco de la basura. De esta revisión, queda claro la importancia de conocer las fuentes y los procesos involucrados en la generación y emisión de amoníaco en las aves de corral y, por lo tanto, adoptar medidas asertivas que puedan minimizar los impactos negativos causados por la emisión de amoníaco.

Abstract Air quality is a major factor in intensive livestock management because air is the main vehicle for the dissemination of physical, chemical, and biological agents that affect the health and welfare of animals and humans. Ammonia is the main gaseous pollutant generated in poultry production. In this study, a literature review was conducted to highlight each nitrogen transformation stage during poultry production, while explaining the conversion mechanisms from the ingestion of crude protein to nitrogen volatilization into the atmosphere as ammonia gas. In summary, the steps for the synthesis of uric acid and the excretion of poultry, mineralization of nitrogen present in excreta, and volatilization of ammonia from litter are presented. Based on this review, the importance of understanding the sources and processes involved in ammonia generation and emission in poultry production is clear, thereby allowing the adoption of assertive measures that could minimize negative effects caused by ammonia emission.

ABSTRACT This study aimed to assess the anaerobic digestion response of laying hen manure with different inclusion levels of biochar in batch reactors as measured by physicochemical parameters, biogas production and digestate quality. Four levels of biochar inclusions (0, 2.5, 5.0 and 7.5%) were tested with 3 replicates each. Twelve two-liter anaerobic batch reactors were used for 86 days at 35°C. Substrate and digestate of each treatment were assessed for monitored parameters, biogas production and digestate quality. Increased levels (0, 2.5, 5.0 and 7.5%) of biochar were found to gradually reduce total ammonia nitrogen (1794.33, 140.84, 950.81 and 509.32 mg.L-1, respectively). Despite the positive effect of biochar to accelerate initial biogas production, its use at any inclusion rate did not contribute significantly to biogas production in terms of biogas yield or digestate quality as compared to control treatment.

RESUMO O monitoramento ambiental em instalações animais, que inclui o armazenamento de dados coletados de forma robusta, prática e viável, é um desafio constante. O objetivo deste estudo foi desenvolver um data logger confiável para monitorar a temperatura e umidade relativa do ar dos aviários e avaliar a adequação do projeto usando instrumentos padrão de referência comercialmente disponíveis. O data logger experimental foi instalado junto com um data logger comercial, um termômetro de mercúrio e uma sonda de umidade relativa do ar calibrada Vaisala HMP110 em um abrigo meteorológico. A análise de regressão linear foi realizada com a temperatura e a umidade relativa do ar coletadas, para desenvolver equações de calibração. O índice Nash-Sutcliffe e o erro relativo foram calculados para validar o data logger experimental. As equações de calibração de temperatura do ar e de umidade relativa do ar apresentaram Nash-Sutcliffe de 0,993 e -0,281 para o data logger comercial e, 0,913 e 0,932 para o data logger experimental. O erro relativo médio das leituras de temperatura do ar foi de 3 e 1% e da umidade relativa do ar 5 e 20%, para o data logger experimental e comercial, respectivamente. O data logger experimental armazenou de forma confiável todos os dados coletados, sem erro, no cartão micro-SD. O data logger experimental pode ser considerado de baixo custo e suficientemente preciso para monitoramento da temperatura do ar e da umidade relativa do ar em aviários, apresentando desempenho de campo muito próximo ao data logger comercial para medição da temperatura do ar e melhor desempenho que o data logger comercial para medição da umidade relativa do ar.

ABSTRACT The environmental monitoring in animal facilities that includes collected data storage in a robust, practical and feasible way is a constant challenge. The aim of this study was to develop a reliable data logger for monitoring the air temperature and air relative humidity of aviaries and to assess the adequacy of the design using commercially available reference standard instruments. The experimental data logger was installed together with a commercial data logger, a mercury thermometer and a calibrated Vaisala HMP110 air relative humidity probe in a meteorological shelter. Linear regression analysis was performed with the collected air temperature and air relative humidity to develop calibration equations. The Nash-Sutcliffe Index and the relative error were calculated to validate the experimental data logger. The air temperature and the air relative humidity calibration equations presented Nash-Sutcliffe of 0.993 and -0.281 for the commercial data logger, and 0.913 and 0.932 for the experimental data. The mean relative error of the air temperature readings was 3 and 1% and for air relative humidity 5 and 20%, for the experimental and commercial logger, respectively. The experimental data logger reliably stored all collected data without error to the micro-SD card. The experimental data logger can be considered low-cost and sufficiently accurate for monitoring air temperature and air relative humidity in aviaries, presenting field performance very close to the commercial data logger for air temperature measurement, and better performance than the commercial data logger for the measurement of air relative humidity.

Antecedentes: la cuantificación de la tasa de emision de contaminantes tales como el amoniaco (NH3) en instalaciones de producción animal con ventilación natural como las utilizadas en América del Sur es un reto, en parte debido a la dificultad para determinar la tasa de ventilación. Algunos métodos han sido desarrollados para reducir esta dificultad, pero la mayoría de ellos son costosos y complejos, lo que impide su aplicación. Objetivo: el presente trabajo tuvo como objetivo adaptar y validar el método Saraz para calcular el flujo de amoniaco (SMDAE) generado en galpones avícolas con ventilación natural. Métodos: para validar el método propuesto, el flujo de amoniaco (ER; masa de NH3 emitida por unidad de tiempo) fue comparado con los resultados obtenidos por medio de la ecuación ajustada propuesta por Wheeler et al. (2006; ER2). Para su evaluación, los valores obtenidos con los dos métodos (SMDAE y ER2) fueron comparados mediante análisis estadístico. Resultados: el método propuesto se considera adecuado para ser utilizado en las condiciones de ventilación natural con vientos superiores a 0,1 m/s-1 y concentraciones de NH3 superiores a 1 ppm. Conclusión: el método presentó una buena correlación entre los valores determinados y los obtenidos mediante la ecuación estandar para el cálculo de emisiones basada en la concentración de NH3, velocidad del aire y temperatura, lo que lo convierte en una alternativa confiable para hacer inventarios de amoníaco en instalaciones avícolas con ventilación natural.

Background: quantifying the rate of pollutant emissions, such as ammonia (NH3), from naturally ventilated animal production buildings in structures, such as those used in South America, is challenging mainly due to the challenge of determining building ventilation rate. Some methods have been developed to reduce this difficulty, but most are costly and complex, preventing their implementation.. Objective: the present work aimed to adapt and validate the Saraz method for the determination of ammonia emissions (SMDAE) from naturally ventilated poultry houses. Methods: to validate the proposed method, the ammonia emission rate (ER; NH3 mass emitted per unit time) was computed using the adjusted equation proposed by Wheeler et al.(2006; ER2). For evaluation purposes, the data obtained from the two measuring methods (SMDAE and ER2)were statistically analyzed. Results: the proposed method was considered adequate for use under conditions of natural ventilation with wind speeds greater than 0.1 m/s-1 and NH3 concentrations greater than 1 ppm. Conclusion: the method demonstrated a good correlation between its values and those obtained by the standard equation for calculating emissions based on NH3 concentration, air speed and temperature, which makes the Saraz method a reliable approach to develop ammonia inventories for naturally-ventilated poultry facilities.

Antecedentes: a quantificação da taxa de emissão de poluentes, tais como a amônia (NH3) em instalações animais abertas e com ventilação natural, como são usadas na América do Sul, é um desafio, em parte devido a dificuldade de determinação da taxa de ventilação. Assim, alguns métodos têm sido desenvolvidos para reduzir esta dificuldade, mas a maioria deles são onerosos e complexos, inviabilizando a sua aplicação. Objetivo: o presente trabalho objetivou-se adaptar e validar o método Saraz para determinar o fluxo de NH3 (SMDAE) emitida dos galpões avícolas submetidos à ventilação natural. Métodos: para fazer a validação do método proposto, o fluxo de amônia (ER; massa de NH3 gerada por unidade de tempo) foi comparada com os resultados obtidos por meio de equação ajustada proposta por Wheeler et al. (2006; ER2). Para a avaliação proposta, os valores obtidos com os dois métodos usados (SMDAE e ER2) foram comparados mediante analise estadística. Resultados: o método proposto mostrou poder ser usado com confiabilidade em condições de ventilação natural com ventos maiores que 0,1 m/s-1 e concentrações de NH3 maiores que 1 ppm. Conclusão:o método apresentou uma boa correlação entre os valores encontrados pelo método proposto e aqueles obtidos na equação característica para o cálculo de emissões a qual é baseada no conhecimento da concentração de NH3, velocidade e temperatura do ar, o que torna o método como uma alternativa viável para fazer inventários de amônia em instalações aviárias com ventilação natural.

El objetivo del presente trabajo fue avalar y validar un simple y preciso método definido "método Saraz para determinar emisiones de amoniaco" (SMDAE), basado en un método de difusión de masa, para determinar el flujo de amoniaco debido a la convección de la masa (NA") generada en la cama aviaria. Se encontró que el flujo de amoniaco puede ser obtenido por el método difusivo SMDAE. El método SMDAE presentó una eficiencia en la recuperación del amoniaco volatilizado de 77 ± 4% y puede ser usado con concentraciones de amoniaco mayores 0.5 ppm.

The present work aimed to adapt and validate a precise and simple application method defined as the "Saraz method for the determination of ammonia emissions" (SMDAE), based on the method of mass diffusion, to determine ammonia flux due to mass convection from broiler litter. It was found that ammonia flux (N"A) can be obtained by the SMDAE diffusion method. The SMDAE method presents a recovery efficiency for volatilized ammonia of 77 ± 4% and can be used for ammonia concentrations as high as 0.5 ppm.

Estudos envolvendo o uso de microalgas cada vez mais se intensificam, pelo potencial que apresentam para a produção de biocombustíveis, por ser uma fonte de energia renovável que não compete diretamente com a produção de alimentos e por possibilitar a obtenção de um combustível com menor impacto ambiental quando comparado ao combustível fóssil. Neste contexto, a utilização de microalgas está diretamente associada à sua capacidade de ser produzida em larga escala e de ser extraída do meio de cultivo. Os estudos reológicos são importantes para a obtenção das informações necessárias na elaboração dos projetos e dos equipamentos que serão utilizados nas diversas operações existentes nos sistemas de produção e de extração da biomassa algal. Na avaliação de diferentes níveis de concentração de biomassa seca, foram realizados estudos do comportamento reológico de cultivos de Chlorella sp. BR001 e Scenedesmus sp. BR003. O modelo de Lei de Potência ajustou bem aos dados de tensão de cisalhamento em função da taxa de deformação. Em todas as concentrações, os cultivos apresentaram comportamento não newtoniano. Verificou-se para Scenedesmus sp. BR003 pouco efeito da concentração de biomassa na viscosidade aparente e na tensão de cisalhamento.

Studies involving the use of microalgae are increasingly intensifying for the potential they present to produce biofuels, because they are a renewable energy source that does not compete directly with food production, and because they enable the obtaining of a fuel with less environmental impact when compared to fossil fuel. In this context, the use of microalgae is directly associated to its capacity to be produced on a large scale and to be extracted from the culture medium. Rheological studies are important for obtaining the information needed in the elaboration of projects and equipment that will be used in various operations existing in systems of production and extraction of algal biomass. In the evaluation of different levels of dry biomass concentration, studies have been conducted of the rheological behavior of cultures of Chlorella sp. BR001 and Scenedesmus sp. BR003. The Power Law model adjusted well to the data of shear stress as a function of strain rate. In all concentrations the cultures showed non-Newtonian behavior. It was observed to Scenedesmus sp. BR003 little effect of biomass concentration on the apparent viscosity and shear stress.

En regiones de clima tropical, como es el caso de Brasil, básicamente todas las instalaciones usadas en la producción intensiva de pollos de engorde y de otros animales de interés económico que trabajan gran parte del tiempo con instalaciones abiertas y con ventilación forzada. La falta de control sobre la masa de aire renovada en cada intervalo de tiempo, bien como de la velocidad y uniformidad del aire de la ventilación que dificulta el cálculo de la cantidad de gases (amoniaco y otros) generados por la actividad en determinado momento. Este hecho constituye una dificultad en la evaluación del potencial contaminante ocurrido en estos ambientes abiertos, bien como en la comparación con los datos encontrados en los galpones cerrados utilizados en climas templados, ya que todos los países desarrollados de Europa y América del Norte disponen de metodologías para determinar el valor de las emisiones de gases en las instalaciones cerradas utilizadas en este tipo de regiones. Por lo tanto, este trabajo, busco analizar algunas metodologías usadas para determinarlas tasas de emisión de amoniaco en galpones de pollos de engorde cerrados, en países de Europa y de Estados Unidos de América (USA), y verificar la posibilidad de aplicarlas, a través de su adaptación y empleo en estructuras abiertas usadas en el Brasil y en otros países de América del Sur. Una evaluación cuantitativa, mostro quelos métodos con mayores características de adaptación a las condiciones de operación y a los diferentes tipos de acondicionamiento ambiental de galpones con sistemas de ventilación de presión positiva o con ventilación natural, son el método de trazado de sistemas de gases interno y de unidades de monitoreo continuo con las unidades portátiles de monitoriamiento (PMU) y unidades de monitoreo móviles para emisiones al aire (MAEMU). Métodos tales como el método que usa balance de masa y aquellos de difusión pasiva como el "Ferm Tube" y el método Saraz, para la determinación de emisiones de amoniaco (Saraz method for determination of ammonia emissions - SMDAE) propuesto por Osorio (2010), indican también que pueden ser adaptados para las diferentes condiciones de operación de los galpones abiertos.

In regions of tropical and subtropical climates, nearly all installations used for intensive broiler chicken production and other animals of economic interest operate as curtain-sided open structures with assisted mechanical ventilation. The lack of ventilation control in these facilities, along with wind direction and velocity effects on ventilation uniformity, complicates calculation of the quantity of gases (ammonia and others) generated by the litter at a given moment. This fact constitutes a pitfall when evaluating the polluting potential of open environments, and when comparisons with data encountered in closed environment facilities used in temperate climates need to be done. All developed countries of Europe and North America already possess methodologies to determine gas emissions in closed installations commonly found in these regions. Therefore, the objective of the present study was to evaluate some specific methodologies used for determining ammonia emissions from broiler houses located in countries of Europe and the United States, and verify the possibility for application of these methodologies to open structures commonly found in Brazil and other countries of South America. A quantitative evaluation showed that the methods with best characteristics for adaptability to the operational conditions and the different types of conditioned environments of buildings with positive pressure or natural ventilation systems were the internal tracer gas, the portable monitoring unit (PMU) and the mobile air emissions monitoring unit (MAEMU). According to the results, model-based approaches that use mass balance and passive diffusion samplers such as the "Ferm Tube" and the Saraz Method for Determination of Ammonia Emissions (SMDAE) proposed by Osorio (2010), can also be adapted to different operational conditions for open buildings.

El objetivo fue evaluar el uso de la arcilla expandida en concretos livianos, dosificada y elaborada de manera que fuera viable el moldeo de placas con una geometría apropiada, capaz de atender las demandas de confort térmico y de las técnicas para estructuras pecuarias. Modelos de galpones de aves fueron construidos en escala 1:12, de acuerdo con Jentzsch (2002) y localizados en dirección este-oeste. Los techos fueron construidos con tres materiales diferentes: placas prefabricadas de concreto aligerado con arcilla expandida (LWC), tejas en fibrocemento (Fcim) y tejas cerámicas (Cer). Los parámetros evaluados al interior de los modelos reducidos fueron: humedad relativa (HR), índice de temperatura de globo negro y humedad (ITGU) y carga térmica radiante (CTR), durante el verano y el invierno. Los resultados mostraron que los parámetros HR, ITGU y CTR fueron estadísticamente diferentes para cada sistema evaluado. El mejor comportamiento se presentó con el modelo de placas prefabricadas de concreto aligerado con arcillas expandidas (LWC).

This research aimed to evaluate the use of the expanded clay on the light concrete, dosed and executed in order to make possible to mold the roof tiles with appropriate geometry, according to the comfort and technique demands of the animals constructions. Models of poultry livestock facilities were build in scale of 1:12, Jentzsch (2002), and were positioned on the East-West direction. The roofs were made of three different materials each one: roofing tiles of light concrete using expanded clay (LWC), roofing tiles of asbestos-cement (Fcim) and ceramic roofing tiles (Cer). The parameters evaluated inside of the reduced models were: relative humidity (RH), and black globe temperature and humidity index (BGHI) and thermal load of radiation (TLR), during the summer and winter. The results showed that the parameters RH, BGHI and TLR were statistically different among the systems. The best performance happened on the model using tiles of light concrete using expanded clay (LWC).