Design and implementation on real-time monitoring system of laying hens environmental comfort based on LabVIEW

Abstract: Living in a comfortable environment during the period of egg production will enable laying hens to achieve their genetic potential. With the development of the poultry industry to larger scale, the air quality in laying house has become the most important factor affecting the health level and production performance of laying hens. Because of the complexity of environmental factors, such as temperature, relative humidity, wind speed, and concentration of CO2 and NH3, it is difficult to describe the level of the environmental comfort quantitatively. In this study, the real-time system of monitoring environment comfort for laying hens was established by the following methods. Firstly, the comfort thresholds of temperature, relative humidity, wind speed, and concentration of CO2 and NH3 for laying hens were established respectively by investigating relevant references. The results showed that the temperatures for comfortable zone (CZ), less comfortable zone (LCZ) and uncomfortable zone (UZ) were 18-21 ℃, 13-18 or 21-26 ℃, and <5 ℃ or >30 ℃ respectively. As for the RH, the temperatures for these 3 zones were 60%-70%, 40%-60% or 70%-72%, and <40% or >72% respectively. The ranges of wind speed for CZ, LCZ and UZ in winter were 0.1-0.2 m/s, 0-0.1 or 0.2-0.25 m/s and >0.25 m/s respectively, and in summer were 0.5-1.5 m/s, 0.25-0.5 or 1.5-2.5 m/s and <0.25 or >2.5 m/s respectively. And the concentrations of CO2 for these 3 zones were <1 500, 1 500-4 000, and >4 000 mg/m3 respectively; the concentrations of NH3 were <15, 15-20, and >25 mg/m3, respectively. Secondly, the theory of fuzzy comprehensive evaluation was used for data fusion of the environment factors, and AHP (analytic hierarchy process) was applied to determine the weight of the environment factors in winter and summer. The results showed that the weight set of temperature, relative humidity, wind speed, concentration of CO2 and NH3 in winter was 0.428 6, 0.151 1, 0.049 5, 0.282 8, and 0.087 9, respectively, and in summer was 0.432 6, 0.241 8, 0.102 9, 0.081 3, and 0.141 4, respectively. Thirdly, a real-time data collection and analysis system of laying house environment was built through the LabVIEW platform, and the real-time environmental comfort evaluation was presented in this system. Lastly, a new method named comfort time proportion method was developed to collect the statistic data of environmental comfort during feeding period. On the basis of the platform of Agricultural Internet constructed by Key Laboratory of Agriculture Engineering in Structure and Environment, Ministry of Agriculture, the laying houses in the Huangshan Deqingyuan Poultry company and in the Shangzhuang Experimental Station of China Agricultural University were selected as the environmental data acquisition node, and then the real-time monitoring system of environmental comfort for laying hens was tested and verified. Compared with the single environment factor, the system can reflect the environmental comfort of the house more comprehensively. And the environment comfort of the laying house in Deqingyuan was better than that in Shangzhuang Experimental Station in winter. The outcomes of this paper will be helpful for evaluating the environment comfort for laying hens.