Poultry Farming: Why the Right Incubation Temperature Determines Success

In modern poultry farming, a stable barn climate plays a key role — from the incubator all the way to the  brooding and grow-out phases . For chickens, accurate incubation temperature control is a decisive in  chicks developing healthily, hatching evenly, and remaining productive during brooding and grow-out. What many underestimate is that even a deviation of just 0.5 °C can significantly impact hatching and energy consumption. A closer look at the incubation temperature in chickens shows how sensitive the interaction of temperature, humidity, and CO? is and why precise sensor technology is the key to animal welfare and energy efficiency.

Incubation Temperature in Chickens – The Most Sensitive Phase in the Life Cycle

Temperature inside the incubator needs the strongest control throughout the entire life cycle. Ideally, it remains constant between 37.5 °C and 37.8 °C (99.5 °F–100.0 °F) during the first 18 days. This keeps the embryo’s metabolism stable, prevents stress reactions, and ensures uniform development and high hatching rates. Even minor deviations can alter embryonic growth or endanger entire batches. In industrial incubators holding thousands of chicken eggs, precise and reliable temperature data is critical for both biological and economic success.

Challenges in Maintaining the Optimal Incubation Temperature for Chicken Eggs

• Avoiding Temperature Deviations
  Even the smallest fluctuations can increase energy use and reduce successful hatchings. Too high temperatures accelerate metabolism, leading to malformations or premature hatching; too low temperatures slow organ development. Accurate, long-term stable temperature measurement in chicken incubation minimises these risks and prevents unnecessary heating or ventilation cycles that drive up energy consumption.
• Temperature, Humidity, and CO? Work Together
  Temperature never acts in isolation. During the first seven days, the egg requires higher humidity and CO? levels to support optimal embryo development. Afterwards, humidity and CO? levels decrease while oxygen intake rises. In the hatching phase, humidity and CO? increase again. To maintain an ideal incubation temperature for chicken eggs, precise and reliable measurements of temperature, humidity, and CO? are essential.

Perfect Incubator Climate: Requirements for the Three Phases of the Incubation Process

Modern incubators simulate the natural behaviour of a brooding hen. Each phase requires a finely tuned balance between temperature, humidity, and CO?.

Precise temperature and humidity control in industrial incubators

Phase 1 – Pre-Incubation / Early Development (Day 0–7)

During the initial phase, the incubation temperature for chickens remains constant between 37.5 – 37.8 °C (99.5 – 100.0 °F), while relative humidity should ideally be 45–55 % RH. These conditions promote proper organ and vascular development and prevent the eggs from losing too much moisture. Too little humidity causes the eggs to dry out, while excessive humidity impedes gas exchange.  Both lead to developmental issues. During this stage, the eggs should be turned at least 4–6 times per day to ensure uniform development.

Phase 2 – Main Incubation / Growth (Day 8–18)

Once the embryo begins absorbing oxygen through the shell, ventilation increases to meet the growing O? demand. The goal during this stage is growth, the formation of the respiratory membrane, and proper water and weight management. Humidity should be constantly monitored and adjusted to achieve a weight loss of 11–13 % by Day 18. From Day 8 onward, CO? concentration rises to around 2,000 ppm. Here too, maintaining an exact incubation temperature in chickens between 37.5 – 37.8 °C (99.5 – 100.0 °F) is crucial for uniform lung development. Turning the eggs regularly until Day 18 is recommended. From this point, the so-called “lockdown” phase begins, when eggs are transferred to the hatcher. Ventilation is gradually increased toward the end of this stage.

Phase 3 – Hatching (Day 19–21)

During the hatching phase, both CO? levels and humidity rise again. Around 10,000 ppm CO? and 65–75 % RH ensure that the chicks hatch simultaneously and without stress. The ideal incubation temperature for chicken eggs is 36.9 – 37.2 °C (98.4 – 99.0 °F). A dry airflow or rapid cooling leads to weaker chicks, negatively affecting feed intake and growth performance. Even small deviations from target values can reduce hatch rates by several percentage points. At this stage, eggs should no longer be turned, as this could prolong the hatching process. It is also advisable not to open the incubator, to avoid humidity loss and temperature fluctuations.

Even After Incubation, Temperature Remains Crucial in Poultry Houses

Temperature continues to be the key climate factor during the grow-out stage, as it directly affects feed intake, weight gain, and animal health. An overly warm barn climate can quickly lead to heat stress, reducing performance and compromising animal welfare.

This is where the Temperature Humidity Index (THI) comes into play. The THI combines temperature and humidity into a single value that serves as an early warning indicator. Once the THI exceeds 68, chickens begin to show the first signs of stress, which include accelerated breathing, reduced activity, and lower feed intake.

Precise monitoring of barn climate conditions in poultry farming allows ventilation and cooling systems to be adjusted early and before heat stress leads to measurable losses in performance and efficiency.

Precise Measurement – The Key to Animal Welfare and Energy Efficiency

Modern incubators and barn systems often operate fully automatically. However, without reliable measurement data, no control system can work efficiently. Accurate sensors for incubation temperature, humidity, and CO? are not only essential for animal health but also represent a significant economic factor. Even a deviation of ±0.5 °C (±0.9 °F) can cause heating or cooling systems to work harder to reach target values, resulting in higher energy costs. Precise temperature measurement in chicken incubators minimizes fluctuations and keeps energy consumption at the required level.

Reliable sensor technology provides real-time data for controlled, animal-friendly housing even in demanding barn climates. These ensure:

• High temperature accuracy for stable conditions and uniform hatch rates
• Fast response times for precise control of ventilation and humidification
• Minimal maintenance requirements in ammonia-rich and humid environments
• Lower energy costs through efficient climate management

Practical Takeaway: Optimal Temperature for Energy Efficiency and Poultry Health

From incubation to grow-out, stable and consistent temperature for chickens determines failure or success. A constant temperature,  balanced with the right humidity and CO? conditions, ensures higher hatch rates, healthier chickens, and reduced energy consumption. Precise sensor technology increases process reliability in the hatching incubator and lays the foundation for strong, well-developed chicks. It is therefore a key component of efficient and sustainable poultry farming.