This study was carried out with the intention of evaluating the effect of shade on animal behavior. The behavior was measured (grazing, browsing, ruminating and resting) from fifteen cows under two densities (high and low) of tree cover. Significant differences were not found for browsing activity, although it tended to be lower in the treatment with high tree cover and during morning hours. The time spent on grazing during the afternoon was significantly greater (P <0,01) for cows with high tree coverage treatment. The percentage of time dedicated to ruminating and resting was significant (P<0,01) and it was greater for cows in the low tree cover treatment pastures and during morning hours. This study showed that cows from the three different farm types behaved in similar way in their main activities, which reflects that at higher tree cover density the animals spent more time for feeding. The results showed that there is a highly significant difference (P<0,01) between the treatments on milk production. In the higher tree cover treatment, greater milk production was obtained (4,06 vs. 3,15 l per cow at the end of the study). Environmental temperature was taken by means of two techniques, with and without circulation of air, and also the rectal temperature to nine of the fifteen cows under observation. Differences in environmental temperatures were significant (P<0,01) only between times of measurement (morning vs. evening) but not between treatments. Significant differences in rectal temperature were found (P<0,01) between animals and times of measurements, but not between treatments. These results show that between 20 to 32 % shade coverage increases milk production in the dry season, possibly due to increased forage consumption and reduction of caloric stress.
