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Click on “Download PDF” for the PDF version or on the title for the HTML version. If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options. THERMAL CONDITIONED IN RESTING AREA OF FREESTALL FACILITIES AND ITS CONSEQUENCES ON PRODUCTIVE AND PHYSIOLOGICAL RESPONSES IN DAIRY COWSPublished by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: Paper number 054020, 2005 ASAE Annual Meeting . (doi: 10.13031/2013.19474) @2005Authors: S. V. Matarazzo, I. J. O. Silva, M. Perissinotto, D. J. Moura, S. A. A Fernandes Keywords: Evaporative cooling, thermoregulation, heat stress, Holstein This work aimed to evaluate the efficiency of thermal conditioned in resting area of freestall facilities and its consequences on productive and physiological responses in dairy cows. Experimental period was 28 consecutive days of November 2003. Third dairy multiple cows with mean milk production of 20 kg.day-1. Treatments were: non-fan (NF), fan (F) and fan + misting (FM) in direction to animal bedding. Dry bulb temperature (DBT), air relative humidity (RH) and black globe temperature (BGT) inside and outside of facilities were measured every 15 minutes through a period of 24 hours. Milking was realized at 1, 9 and 17 hours and registering daily production. Animals were fed twice a day (10 and 15 hours) and amounts of offered and rejected feed were daily registered. Physiological data, as respiratory frequency (RF), rectal temperature (RT) and skin temperature (ST), were taken at 9, 11, 13, 15 and 17h. The RH was higher in NF (61.8%) and FM (61.8%) treatments than in F (60.3%). The facilities (F) where it was used had higher BGT (27.4C) in relation to NF (27.1C). Also, THI was higher in F (75.0) than in NF (74.5) and FM (74.3) treatments. In relation to physiological parameters, lactating cows of V0 treatment had lower rectal temperature at 11, 13 and 17h. Respiratory frequencies and skin temperature were within normal variation in all treatments. Higher feed intakes were observed in animals of NF (20.5 kg DM.day-1) and F (21.3 kg DM.day-1) treatments, but it did not increase milk productions. (Download PDF) (Export to EndNotes)
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