If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.
PRODUCTIVE RESPONSE OF DAIRY COWS RAISED IN A COOLING BARN LOCATED IN THE PO VALLEY (ITALY)
Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org
Citation: Proceedings of the Seventh International Symposium, 18-20 May 2005 (Beijing, China) Publication Date 18 May 2005 701P0205.(doi:10.13031/2013.18355)
Authors: F. Calegari, E. Frazzi, L. Calamari
Keywords: Dairy cows, milk yield, heat stress, cooling systems
The study was carried out in summer season (from May to August) 2003 on 380 Italian Friesian
cows raised in a free stall barn located in the Po Valley. The barn was equipped with fans plus
misting in the feeding area and fans without misters in the resting area.
The temperature and humidity recorded during the trial indicate that the summer was very hot.
The minimum daily temperatures (month average) varied from 12.7C in May to 20C in
August. The maximum daily temperatures (month average) were of 27.2C in May and 35.5C in
August. Even though the summer was very hot, the milk reduction during lactation in
primiparous and multiparous cows was a little higher than the reduction due to the effect of
lactation phase. The milk yield during the trial has shown, on average, a reduction of 4.0%
/month in mid-lactating primiparous cows (90 200 days in milk) and 7.6% /month in late
lactation (201 300 DIM). The multiparous cows have shown a reduction of 10.5% /month in
middle lactation (90 200 DIM) and 11.6% /month in late lactation (201 300 DIM).
The greater reduction of milk yield has been observed in June in relation to the beginning of the
hot period and more in relation with the minimum daily temperature than the maximum daily
The conditioning system mitigated the negative effect of heat stress on milk yield and the results
highlight the importance of carrying out the ventilation and misting in all areas of the barn.