IMPACT OF MICROLCIMATE AND HEAT STRESS INDEX ON PRODUCTION EFFICIENCY OF BROILER CHICKENS IN OPEN, SEMI-CLOSED, AND CLOSED HOUSING SYSTEMS

Abstract

This study evaluates the impact of microclimate conditions, specifically the Heat Index (HI), on key production efficiency metrics. A non-experimental, observational study was conducted using secondary data from three commercial broiler farms in West Java, Indonesia, representing open , semi-closed, and closed with controlled-ventilation housing systems. Microclimate data were collected from three locations representing each housing system type: Cikampek (Open), Cianjur (Semi-Closed), and Bogor (Closed). Production performance data were recorded at the end of the rearing period. Due to the absence of replication (n=1 per housing system), non-parametric statistical inference could not be applied; therefore, comprehensive quantitative descriptive analysis including absolute comparisons, percentage change, ranking analysis, and effect size estimation was employed.   Data were analyzed using descriptive statistics, The closed house system maintained a significantly lower average HI (155.0) compared to the semi-closed (163.1) and open (165.2) systems. Production efficiency was superior in the closed system, with the best FCR (1.46) and IP (433).  Results showed that the Closed system achieved the most favorable microclimate conditions with the lowest temperature (25.4°C) and Heat Index (155.0), representing a 19.6% temperature reduction and 6.2% Heat Index reduction compared to the Open system (31.6°C; 165.2).  Ranking analysis confirmed a consistent performance hierarchy: Closed > Semi-Closed > Open, with the Closed system achieving a perfect mean rank of 1.00 across all parameters. The Heat Index showed strong descriptive associations with production outcomes, where lower Heat Index values corresponded to improved performance. This study demonstrates that Closed housing systems with enhanced environmental control effectively mitigate heat stress and significantly improve broiler production efficiency in tropical conditions. However, due to limited replication, these findings should be interpreted as descriptive evidence, and future studies with adequate replication are recommended to enable robust statistical inference.