On the controlling of temperature: A proposal for a real-time controller in broiler houses

ABSTRACT: Environmental conditions in broiler houses, specifically temperature, are key factors that should be controlled to ensure appropriate environment for broiler rearing. In countries with tropical/subtropical climate, like Brazil, high temperatures produce heat stress to animals, affecting the production process. This research proposes a real-time model to control temperature inside broiler houses. The controller is a self-correcting model that makes real-time decisions on the ventilation system operation (exhaust fans) together with temperature prediction at the facility. The model involves partial differential equations (PDE) whose parameters are updated according to data registered in real-time. Some experiments were carried out at a pilot farm in the municipality of Jundiaí, São Paulo State, Brazil, for different periods during winter and summer. The results based on simulations in comparison with the current automatic ventilation system show that the model is consistent to keep temperature under control for an efficient production. The model achieved a bias of 0.6 °C on average in comparison with the ideal temperature, whereas the automatic controller measured a bias of 3.3 °C, respectively. Future lines suggest that this approach could be useful in many other situations that involve environmental control for livestock production.

On the controlling of temperature: A proposal for a real-time controller in broiler houses

Environmental conditions in broiler houses, specifically temperature, are key factors that should be controlled to ensure appropriate environment for broiler rearing. In countries with tropical/subtropical climate, like Brazil, high temperatures produce heat stress to animals, affecting the production process. This research proposes a real-time model to control temperature inside broiler houses. The controller is a self-correcting model that makes real-time decisions on the ventilation system operation (exhaust fans) together with temperature prediction at the facility. The model involves partial differential equations (PDE) whose parameters are updated according to data registered in real-time. Some experiments were carried out at a pilot farm in the municipality of Jundiaí, São Paulo State, Brazil, for different periods during winter and summer. The results based on simulations in comparison with the current automatic ventilation system show that the model is consistent to keep temperature under control for an efficient production. The model achieved a bias of 0.6 °C on average in comparison with the ideal temperature, whereas the automatic controller measured a bias of 3.3 °C, respectively. Future lines suggest that this approach could be useful in many other situations that involve environmental control for livestock production.(AU)

On the controlling of temperature: A proposal for a real-time controller in broiler houses

ABSTRACT: Environmental conditions in broiler houses, specifically temperature, are key factors that should be controlled to ensure appropriate environment for broiler rearing. In countries with tropical/subtropical climate, like Brazil, high temperatures produce heat stress to animals, affecting the production process. This research proposes a real-time model to control temperature inside broiler houses. The controller is a self-correcting model that makes real-time decisions on the ventilation system operation (exhaust fans) together with temperature prediction at the facility. The model involves partial differential equations (PDE) whose parameters are updated according to data registered in real-time. Some experiments were carried out at a pilot farm in the municipality of Jundiaí, São Paulo State, Brazil, for different periods during winter and summer. The results based on simulations in comparison with the current automatic ventilation system show that the model is consistent to keep temperature under control for an efficient production. The model achieved a bias of 0.6 °C on average in comparison with the ideal temperature, whereas the automatic controller measured a bias of 3.3 °C, respectively. Future lines suggest that this approach could be useful in many other situations that involve environmental control for livestock production.

Turkey meat quality (Meleagris gallopavo) submitted to different ventilation systems during fattening / Qualidade da carne de perus (Meleagris gallopavo) submetidos a diferentes sistemas de ventilação durante a engorda

The present investigation evaluated the quality of turkey meat produced in two production systems, according to the following parameters: water loss in cooking, drip water loss, texture (shear strength), pH, color, humidity, protein, ashes and lipids. A total of 200 turkey breast samples of 500 g, separated by a batch of 20 samples, from ten aviaries from Santa Catarina, Brazil, were used: five from breeding with a traditional ventilation system and five with a mechanical ventilation system. Samples were obtained after slaughter and frozen at -15°C for 30 days. The results were submitted to variance analysis and the Tukey test. Significant differences were found only in the analysis of drip water loss. The birds of the traditional ventilation system presented 14.26% loss of water drip, while those of the ventilation exhaust system presented a loss of 19.21%. There were no differences in the chemical composition of poultry meat in relation to the production systems.(AU)

O presente trabalho avaliou a qualidade da carne de perus criados em dois sistemas de produção, a partir dos seguintes parâmetros: perda de água na cocção, perda de água por gotejamento, textura (resistência ao cisalhamento), pH, cor, umidade, proteína, cinzas e lipídios. Foram utilizadas 200 amostras de peito de peru de 500 g, separadas por lote de 20 amostras, de dez aviários de Santa Catarina, Brasil, dos quais: cinco provenientes de criação com sistema de ventilação tradicional e cinco com sistema de ventilação mecânica. As amostras foram obtidas após o abate e congeladas a -15°C durante 30 dias. Os resultados foram submetidos à análise de variância e ao teste de Tukey. Diferenças significativas foram encontradas apenas na análise da perda de água por gotejamento. As aves do sistema de ventilação tradicional apresentaram 14,26% de perda de gotejamento de água, enquanto as do sistema de exaustão de ventilação, 19,21%. Não houve diferenças na composição química das carnes de aves em relação aos sistemas de produção.(AU)

Turkey meat quality (Meleagris gallopavo) submitted to different ventilation systems during fattening / Qualidade da carne de perus (Meleagris gallopavo) submetidos a diferentes sistemas de ventilação durante a engorda

The present investigation evaluated the quality of turkey meat produced in two production systems, according to the following parameters: water loss in cooking, drip water loss, texture (shear strength), pH, color, humidity, protein, ashes and lipids. A total of 200 turkey breast samples of 500 g, separated by a batch of 20 samples, from ten aviaries from Santa Catarina, Brazil, were used: five from breeding with a traditional ventilation system and five with a mechanical ventilation system. Samples were obtained after slaughter and frozen at -15°C for 30 days. The results were submitted to variance analysis and the Tukey test. Significant differences were found only in the analysis of drip water loss. The birds of the traditional ventilation system presented 14.26% loss of water drip, while those of the ventilation exhaust system presented a loss of 19.21%. There were no differences in the chemical composition of poultry meat in relation to the production systems.(AU)

O presente trabalho avaliou a qualidade da carne de perus criados em dois sistemas de produção, a partir dos seguintes parâmetros: perda de água na cocção, perda de água por gotejamento, textura (resistência ao cisalhamento), pH, cor, umidade, proteína, cinzas e lipídios. Foram utilizadas 200 amostras de peito de peru de 500 g, separadas por lote de 20 amostras, de dez aviários de Santa Catarina, Brasil, dos quais: cinco provenientes de criação com sistema de ventilação tradicional e cinco com sistema de ventilação mecânica. As amostras foram obtidas após o abate e congeladas a -15°C durante 30 dias. Os resultados foram submetidos à análise de variância e ao teste de Tukey. Diferenças significativas foram encontradas apenas na análise da perda de água por gotejamento. As aves do sistema de ventilação tradicional apresentaram 14,26% de perda de gotejamento de água, enquanto as do sistema de exaustão de ventilação, 19,21%. Não houve diferenças na composição química das carnes de aves em relação aos sistemas de produção.(AU)

Ammonia emissions in tunnel-ventilated broiler houses

Gas production in broiler houses and their emissions are closely related to the microclimate established inside the house according to air temperature, humidity, and velocity. Therefore, the internal house environment is influenced by building typology and ventilation system. The objective of the present study was to evaluate ammonia emission rates in broiler houses equipped with different ventilation systems (negative or positive pressure) and litter conditions (new or built-up). The environment of six commercial broiler houses was evaluated internal and external NH3 concentrations. Ventilation rates were recorded to estimate ammonia emission rates. The efficiency of circulation and exhaust fans was assessed, and higher ventilation rates were determined in negative-pressure houses due to the higher flow of the fans. Houses with new litter increased ammonia emission rates along the rearing period, indicating the relationship between gas emissions, bird age and ventilation rates, and presented a typical curve of NH3 emission increase. Negative-pressure houses with built-up litter presented higher emission rates during the first rearing week due to the high NH3 concentration during the brooding period, when the ventilation rates required to maintain chick thermal comfort are low. Although the results of the present study indicate an advantage of the positive-pressure systems as to gas emissions, further research is needed reduce gas emissions in broiler houses with negative-pressure systems.

Ammonia emissions in tunnel-ventilated broiler houses

Gas production in broiler houses and their emissions are closely related to the microclimate established inside the house according to air temperature, humidity, and velocity. Therefore, the internal house environment is influenced by building typology and ventilation system. The objective of the present study was to evaluate ammonia emission rates in broiler houses equipped with different ventilation systems (negative or positive pressure) and litter conditions (new or built-up). The environment of six commercial broiler houses was evaluated internal and external NH3 concentrations. Ventilation rates were recorded to estimate ammonia emission rates. The efficiency of circulation and exhaust fans was assessed, and higher ventilation rates were determined in negative-pressure houses due to the higher flow of the fans. Houses with new litter increased ammonia emission rates along the rearing period, indicating the relationship between gas emissions, bird age and ventilation rates, and presented a typical curve of NH3 emission increase. Negative-pressure houses with built-up litter presented higher emission rates during the first rearing week due to the high NH3 concentration during the brooding period, when the ventilation rates required to maintain chick thermal comfort are low. Although the results of the present study indicate an advantage of the positive-pressure systems as to gas emissions, further research is needed reduce gas emissions in broiler houses with negative-pressure systems.