29 April 2021
Regulation of the microclimate in the stall barn and natural ventilation
The summer season is just around the corner, and with it, the needs of farm cattle become even more apparent. The observation and management of dairy cows is, from their very first moments of life, an increasingly delicate process that requires constant updating and maintenance to ensure that their environment is welcoming and conducive to healthy and strong growth.
In winter, farmers often resort to the natural ventilation system; however, in the hottest periods, this cooling method may not be sufficient to guarantee the well-being of their animals. Let’s take a look at why in this article.
THE RIGHT TEMPERATURE IN THE STALL BARN
Temperatures that for us can be described as mild, 24–25 °C, can for dairy animals manifest initial complications, progressively adding to the impact of solar radiation, relative humidity (RH) and temperature changes, resulting in overall heat stress.
In order to optimise general health, average stall barn temperatures should vary between lactating and dry cows. Among other things, lactating cows require a temperature neutrality of approximately -5 °C to 21 °C, but dry cows deserve equal attention due to the period of stress to which they are subjected, with a higher temperature of approximately 0 °C to 24 °C. Considering that optimum temperatures can never be finalised due to factors such as humidity and air velocity, the reference average should be between 7 °C and 20 °C with a humidity level of no more than 40/50%.
NATURAL VENTILATION AND COOLING SYSTEMS
In the cooler period, systems are used to reinforce the natural methods of recirculation through upward air movement by means of side openings and upper domes. In fact, the cold season, regardless of the region, often relies on natural ventilation, also known as the “passive” system, thanks to the ability to recycle the air without the use of any energy source. An optimal process to significantly reduce costs and maintenance through a so-called “chimney” effect.
However, given the physiological tendency of cows to give off heat, as temperatures rise, natural systems may not be sufficient to counteract the influx of hot air, so the need for forced cooling and ventilation comes into play. Thermoregulation instruments are distributed between sleeping quarters and feeding areas accompanied by sprinklers in the self-locking yoke panels at an alternating rhythm to guide a cycle of cooling and drying (see link) of the cows’ coats, facilitating temperature regulation. The destratifiers, with high energy efficiency and low consumption, allow constant recycling and redistribution of the air, thanks to the constant movement of six aluminium blades.
New technologies make it possible to combine these systems with automatic control units, which, thanks to temperature/humidity detection, allow automatic regulation of the bath-drying cycles.
In conclusion, the monitoring of the microclimate in a stall barn is just one of the many factors to be considered, possibly already at the design stage of the facility, in order to achieve a significant improvement in animal welfare and greater results in terms of quality and productivity.