Given the need to obtain systems to better control broiler production environment, we performed an experiment with broilers from 1 to 21 days, which were submitted to different intensities and air temperature durations in conditioned wind tunnels and the results were used for validation of a fuzzy model. The model was developed using as input variables: duration of heat stress (days), dry bulb air temperature (°C) and as output variable: feed intake (g) weight gain (g) and feed conversion (g.g -1 ). The inference method used was Mamdani, 20 rules have been prepared and the defuzzification technique used was the Center of Gravity. A satisfactory efficiency in determining productive responses is evidenced in the results obtained in the model simulation, when compared with the experimental data, where R 2 values calculated for feed intake, weight gain and feed conversion were 0.998, 0.981 and 0.980, respectively. KEYWORDS: fuzzy logic, animal environment, poultry. MODELAGEM FUZZY DO DESEMPENHO DE FRANGOS DE CORTE, CRIADOS DE 1 A 21 DIAS, SUBMETIDOS A ESTRESSE TÉRMICORESUMO: Diante da necessidade de se obter sistemas, para melhor controlar o ambiente de produção de frangos de corte, foi realizado um experimento com frangos de corte de 1 a 21 dias, os quais foram submetidos a diferentes intensidades e durações de temperaturas do ar em túneis de vento climatizados, e os resultados foram utilizados para a validação de um modelo fuzzy. O modelo foi desenvolvido, utilizando como variáveis de entrada: duração do estresse térmico (dias), temperatura de bulbo seco do ar (°C) e, como variável de saída: consumo de ração (g), ganho de peso (g) e conversão alimentar (g.g -1 ). O método de inferência utilizado foi o de Mamdani, tendo sido elaboradas 20 regras, e a técnica de defuzzificação usada foi a do Centro de Gravidade. Nos resultados, obtidos na simulação do modelo, quando comparados com os dados experimentais, evidencia-se uma eficiência satisfatória na determinação das respostas produtivas, nas quais os valores de R 2 calculados, para consumo de ração, ganho de peso e conversão alimentar, foram de 0,998; 0,981 e 0,980, respectivamente. PALAVRAS-CHAVE:Lógica fuzzy, ambiência animal, avicultura.

Broiler chickens are classified as homoeothermic animals and require a production environment within well-defined thermal comfort intervals. Therefore, the development of algorithms (mathematical models) to control the environment that can be embedded in microcontrollers becomes necessary. Hence, this work aimed to develop a fuzzy model for predicting the productive performance of broiler chickens as a function of the thermal environment during the various breeding phases. The Mamdani inference and defuzzification methods were used, by means of the gravity center, to develop the fuzzy model. Two hundred and forty-three rules with weighting factors of 1.0 each were elaborated. Three commercial warehouses (conventional system, wind tunnel with negative pressure and dark house) were evaluated for testing of the model. We recorded the thermal environment (dry bulb temperature-tdb and relative humidity-RH) and productivity data (feed intake-FI, weight gain-WG, feed conversion-FC and productive efficiency index-PEI) over six lots in each aviary. The resulting fuzzy model was capable of forecasting FI, WG, FC, and PEI, with standard deviations and mean percentage errors of 4.16 g and 5.05%, 146.53 g and 8.04%, 0.06 g g-1 and 4.96%, and 24.51 g and 12.29%, respectively.

Esta pesquisa foi realizada com o objetivo de avaliar o reaproveitamento de embalagens Tetra Pak-® junto a telhas de fibrocimento e o uso de telhas recicladas à base de embalagens Tetra Pak-® no conforto térmico em modelos físicos em escala reduzida de instalações rurais. Para testar os diferentes materiais de cobertura, foram construídos seis modelos: telhas recicladas à base de embalagens Tetra Pak-®, telhas cerâmicas, telhas de fibrocimento, telhas de alumínio, telhas de fibrocimento com subcobertura de embalagens Tetra Pak-® com a face aluminizada voltada para cima e telhas de fibrocimento com forro de embalagens Tetra Pak-® com a face aluminizada voltada para cima. Os dados foram coletados no período de dezembro de 2012 a fevereiro de 2013, das 9 às 17 h, em intervalos de 20 min. É possível afirmar que as telhas recicladas apresentaram índices de conforto térmico com valores semelhantes aos apresentados por outros materiais de cobertura, como as telhas cerâmicas. O reaproveitamento das embalagens Tetra Pak-® como forro contribuiu para redução dos valores médios de índice de temperatura e umidade, índice de temperatura de globo e umidade e carga térmica de radiação.

Physiological parameters such as respiratory frequency and rectal temperature stand out as indicators for heat stress in pigs, however, requiring time and labor for measurements. The possibility of using infrared thermography associated with prediction systems of these physiological variables can help in decision making, allowing greater welfare and productivity of the animals. With this objective, an experiment was carried out with growing pigs submitted to acute and chronic heat stress, working with a thermoneutrality temperature (22° C) and heat stress (34° C). The results were used for the development of a fuzzy model using as input variables: air dry bulb temperature (°C), average surface temperature (°C) and, as output variables: respiratory frequency (movements/minute) and rectal temperature (°C). The method of inference used was the one of Mamdani having been elaborated six rules and the defuzzification technique used was the one of the Center of Gravity. In the obtained results on simulation model when compared with experimental data was evidenced satisfactory efficiency in respiratory frequency determination and the rectal temperature, in which the R 2 values calculated were respectively 0.997 and 0.951 for acute stress and 0.993 and 0.964 for chronic heat stress.

The traditional techniques to measure heat production (HP) are calorimetry (direct and indirect) and comparative slaughter. Both methods are expensive and require extensive amounts of time and infrastructure. Infrared thermography (IRT) could be a faster and less expensive alternative to estimate cattle HP. The objective of this project was to evaluate the use of the IRT technique as an indicator of HP in cattle. A total of 24 bulls (12 Nellore and 12 Black Angus) with initial BW of 380 ± 7 kg were used. Initially, 4 animals of each breed were harvested (baseline animals) and simple regressions were developed for each breed from these baseline animals to estimate the initial chemical composition of the remaining bulls. Eight animals of each breed were fed a silage/concentrate diet for ad libitum intake in individual stalls. On the 25th, 50th, and 75th experimental day, infrared thermal images (Fluke Ti 55ft; Fluke Corporation) were taken of each animal's face to access skin and ocular surface temperatures. A metabolism trial was conducted to estimate the ME intake (MEI). After 84 experimental days, the cattle were harvested and retained energy (RE) and HP were calculated. The data were analyzed using the MIXED and REG procedures of SAS adopting a significance level of 0.05. Angus cattle had a greater daily MEI, HP, and skin and eye temperatures than Nellore. We found significant correlations ( ≤ 0.005) between daily HP and maximum ( = 0.65) and average skin temperatures ( = 0.65) and maximum ( = 0.65) and average ocular surface ( = 0.69) temperatures recorded on d 50. Infrared thermography has potential to be used to evaluate HP in cattle.

ABSTRACT:The spatial illuminance distribution interferes in the commercial production of eggs and electric energy consumption, being considered the second major source of costs in the production chain. Therefore, in this study the objective was to evaluate the spatial distribution of the illuminance level and electric energy consumption in two commercial aviaries for egg production. The first aviary was equipped with compact fluorescent lamps (CFL) and the second, with light-emitting diode (LED) lamps. The illuminances in the aviaries were analyzed using descriptive statistics and their spatial distribution through geostatistics. It was found that the aviary equipped with CFL showed better uniformity in the illuminances distribution and better results in attending the luminance levels of 5 lux. On the other hand, the one equipped with LED lamps showed electric energy consumption 43.52% less than the one equipped with compact fluorescent lamps (CFL).

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Broiler chickens submitted to different intensities and durations of thermal stress are subject to variation in cloacal temperature and, consequently, to a decrease in performance. Given the complexity of these interactions, artificial intelligence is a useful methodology for decision-making. Thus, this study aimed to assess and predict, by means of a fuzzy model, the cloacal temperature of broiler chickens submitted to thermal stress in the second week of life, with varying durations and intensities, in climatized wind tunnels. Mamdani's inference and defuzzification methods by means of the center of gravity were used. One hundred and twenty rules were elaborated. The developed fuzzy model was used to predict the cloacal temperature of broiler chickens on the day of thermal stress as a function of air dry-bulb temperature (°C), stress duration (days), and the number of days after thermal stress. Cloacal temperature values simulated by the fuzzy model showed standard deviations and percentage errors lower than 0.02 and 0.08%, respectively, when compared to those obtained experimentally.