The goal of this study was to investigate acoustic characteristic of feed anticipating calls of heifers and cows. 6 cows and 6 heifers housed in a pen ($6.0m{\times}10.0m$) which was bedded with sawdust and straw. They were fed a standard ration of co...
The goal of this study was to investigate acoustic characteristic of feed anticipating calls of heifers and cows. 6 cows and 6 heifers housed in a pen ($6.0m{\times}10.0m$) which was bedded with sawdust and straw. They were fed a standard ration of commercial concentrate and hay was ad libitum. The calls of heifers and cows were divided into Type 1 and Type 2 which were classified based on the shapes of waveform and spectrograms, respectively. There was difference in the fundamental frequency (P < 0.0001) and $1^{st}$ formant (P < 0.0077) among the calls. Acoustic parameters with the exception of fundamental frequency and $1^{st}$ formant were no difference between cows' calls and heifers' calls (P > 0.05). Duration of cows' calls was lower than that of heifers' calls, whereas the intensity of Type 1 calls was higher than that of Type 2 calls (P > 0.05).