STUDY REGARDING RUMINATION BEHAVIOUR IN MULTIPAROUS ROMANIAN BLACK AND WHITE COWS DURING SUMMER SEASON

In this study rumination activity of ten lactating Romanian Black and White multiparous cows housed in total confinement in tied stalls was observed continuously 24 hours per day. Researches were carried out during two weeks, in June 2008. To record the behaviour four video cameras were used connected to a video capture device of 125 fps (frames per second) of CC9622BIR type. There were two experiments, first experiment (48 hours) average air temperature in the shed was 31.76 ºC and24.16 ºC during the second experiment. During first experiment, cows spent ruminating on average in 24 hours 350.60 minutes, in 14.60 periods, with an average length of a rumination period of 24.81 minutes. During second experiment, cows spent ruminating on average per day, 543 minutes, in 17.10 ruminating periods and with an average length of each period of 26.64 minutes. Differences between the two experiments during 24 hours were registered to be 102.40 minutes for total time spent ruminating, 2.50 ruminating periods and 1.83 minutes for the average length of a rumination period. Thus, in spite of same housing and feeding conditions, rising temperature upwards of superior thermal comfort of the breed (27-28 ºC), rumination process is severe affected.