Changes in acoustic parameters with elapsed days in calf vocalization after weaning

Abstract

This study aimed to investigate the effect of elapsed time on the acoustic parameters of vocalizations in weaned Japanese Black calves. The number of vocalizations (3 hours/6 heads/day) decreased dramatically from 1,711 on the day of weaning to 24 on the fifth day. Calf vocalizations were compared using Praat phonetic analysis software, and acoustic parameters were quantified from waveform shape and spectrogram analysis. The fundamental frequencies (average, minimum, and maximum), intensity, and vowel components (formants 1–5) in the extracted portion of calf vocalizations were compared among the elapsed days. Significant differences were observed in the fundamental frequencies and formants. The fundamental frequency was in the range of 160 Hz on the first and second days after weaning but increased significantly to 300 Hz or more on the third day after weaning. In contrast, formants 1 and 2 decreased as the number of days passed, and formant 5 increased from the third day to fourth day of weaning. In addition, the change in the regularity of the acoustic parameters using the common logarithm was greatest at the fundamental frequency, and the correct response rate was 72% in the discriminant analysis using days 1, 2, and 3–5 as the groups. The acoustic parameters of calf vocalizations after weaning changed with elapsed time, such as the fundamental frequency, which increased by approximately two times.

Journal of Warm Regional Society of Animal Science, Japan 68 （2）: 87-95, 2025