Behavior responses of Holstein dairy cows with constant or limited access to shade

The experiment was carried out at Piracicaba, Sao Paulo, Brazil, from Janua ry to February 1993, with the objective of evaluating the behavior response s of Holstein cows, with constant or limited access to shade. The experimen tal design used was completely randomized. Twenty four dairy cows were used , at different lactation stages and production levels, kept in two free sta ll barns, with or without protection against solar radiation in south-east and north-west edge. The behavior parameters studied were: alimentation, ru mination, rest time and frequency and water ingestion frequency. The protec tion of the free stall barn didn't affect the behavior responses. The alime ntation, rumination and rest time, daily, were 3.4, 7.0 e 9.0 hours, respec tively. The highest alimentation frequencies were before and after milking. The rumination was mainly during nocturnal period; the rest was more frequ ent during the period with higher solar radiation. The animals stayed more time in the shelter (13.4 vs 2.5 h/day). The highest daily water ingestion frequencies were in the hot time and next milking, mainly.