Ensuring poultry health, preventing disease outbreaks, and optimizing productivity require timely environmental monitoring and control. This paper presents a comprehensive full-stack IoT system that bridges hardware and web technologies for real-time monitoring of poultry farm conditions. The system captures sensor data including temperature, humidity, and gas levels using Arduino-based devices and transmits it via WebSocket to a scalable Django Channels backend. A modern React/Vite frontend visualizes the live data stream and issues alerts, allowing farm managers to respond rapidly to adverse changes. The dashboard also provides configurable monitoring intervals and interfaces for automated control managed by Arduino. Evaluated in a simulated poultry environment, the system demonstrates low-latency data delivery, consistent real-time visualization, and effective anomaly detection. This work offers a deployable and extensible monitoring framework, forming the foundation for future integration with AI-based poultry disease classification and decision support tools.