Winter ventilation case study in three veal barns

One mechanically ventilated and two naturally ventilated veal barns were ev aluated on a "common-day" basis: calf age and outdoor winter weather condit ions over 24-h were similar at all three barns. Monitoring of environmental characteristics within each barn was accomplished using small, portable da taloggers for continual monitoring of temperature and relative humidity at three locations within the barn, including near the calf stalls, and outsid e weather conditions. Results demonstrate the three veal barns were operate d at cooler temperatures by 3 to 8 degrees C (5 to 14 degrees F) than gener ally recommended for veal production. The mechanically ventilated facility used supplemental heat. with no supplemental heat, the naturally ventilated facilities had high relative humidity, and low temperatures, especially at calf level. New criteria for evaluating cold housing for veal may be neede d since healthy, acceptable market weight calves were produced in each faci lity, All three operators understood the importance of providing continuous ventilation even during coldest conditions though more effective interior air distribution is recommended. Improvements to inlet design and function are commencing. Modifications of current veal calf environmental control re commendations should be considered.