Mathematical Modelling of Gas Concentrations in Commercial Broiler Houses: Simulations and Validation in Summer Season

The primary goal of industrial poultry houses is to offer an optimal environment for the birds to attain the highest rate of growth and wellbeing. In order to regulate the harmful gases present in these livestock buildings, this research provides a mathematical model of ammonia and Carbon dioxide concentrations present within these houses. The real data has been collected over a summer growth cycle in a Mediterranean Moroccan broiler house designed for 23 000 broilers which have been kept from birth until around 45 days of age. The broilers are monitored according to three ventilation modes related to their age, i.e., natural ventilation for the first age, average ventilation for the second and maximum one for the last category. The amount of NH3 and CO2 inside the building climbed with the age of the bird and litter, the respiration rate, and the stocking density. The lowest concentrations of both gases have been observed in the initial phase of the grow-out period, and the highest emissions have been recorded during the third age of the cycle due to the increased ventilation rate. In order to test and validate the model, simulations have been carried out and have been compared to the real measurements. The predicted CO2 and NH3 concentrations have been confirmed by statistical analysis during the production cycle with a global Root Mean Square Error (RMSE) of 0.7584 ppm for ammonia and 318.12 ppm for Carbon dioxide. The performance of the daily average air quality index is satisfactory in general.