Evaluation of the intervals and numbers of observations on the ingestive behavior of dairy heifers confined

Abstract

The objective of this study was to assess the effect of the intervals and numbers of observations on the ingestive behavior of confined dairy heifers. We used 20 heifers Holstein x Zebu, with initial body weight of 165.5kg and mean age of 13 months. The heifers were divided into four feeding groups, composed of inclusions of cocoa meal based diets (0; 7; 14 and 21%). The treatments were the intervals (five; 10; 15; 20 and 30 minutes), number of repetitions (four, three, two and one), and turns (four, three, two and one) the observation of ingestive behavior. The evaluation came at the end of each period of 21 days of data collection for 24 hours, and activities recorded in five different intervals: 0; 10; 15; 20 and 30 minutes. Aspects of ingestive behavior were observed in four, three, two and one replicates and turns. There was no significant effect of scales of record on the time of feeding, ruminating and idle, either on the efficiencies of feeding and rumination. For variables related to rumination activity, no differences between different numbers of observations, nor for the different turns of observation. The determination of the total times of the activities of feeding, ruminating and idle, and efficiencies of feeding and rumination of different nutrients can be performed with an interval of observation of up to 30 minutes.