Methodological aspects of ingestive behavior of lactating cows grazing “Brachiaria decumbens”

Abstract

This study evaluates the components that comprise animal behavior in different methodologies to discretize time series of lactating cows (Holstein vs. Zebu) grazing Brachiaria decumbens. The experimental design was completely randomized, evaluated five time intervals and luminosity effects on eating behavior, and used 12 replications for each evaluation. Tukey test and F test at 5% significance were used to compare the time intervals and the light influence on the feeding behaviour, respectively. The averages of daily eating, ruminating and resting did not have interference on different time intervals. However, when assessing the frequency of eating, ruminating and resting, all the time intervals differ. Evaluating the influence of light on feeding behavior, daily and nightly periods differ both on the time spent and on daily frequencies of eating, rumination, and resting. It was found that cows allocated greater percentage of their daily time to feeding compared to other behavioral activities. It is possible to use observations with intervals of 30minutes to determine the average time of each daily activity. However, to evaluate the frequencies of these activities, the intervals must be of five minutes, because longer intervals underestimate the results.