Effect of low magnetic field exposure on feeding behaviour of dairy cattle and relationship to human
2001
Broucek, J. | Uhrincat, M. | Sandor, A. | Marencak, S. (Vyskumny Ustav Zivocisnej Vyroby, Nitra (Slovak Republic)) | Arawe, C.W.
Twenty-two Holstein calves were included to an experiment. They were divide to trial and control groups. The low magnetic field impacted during intrauterine development on the animals of the trial group. The dams of trial calves were exposed to a low magnetic field at the flux density ranging from 42.1 ÝT (head) to 21.9 ÝT (hind part) during the 196th to 258th day of gestation, while the dams control calves were in an environment with a zero magnetic field. Every animal was subjected to six, 10-minute tests during three consecutive days at the 12-months age. A gray manger containing concentrate was placed in square no. 8. The animals were exposed to isolation and silence in the first two tests and to an unfamiliar person sitting on square no. 4 in the third and fourth tests. Noise (110 dB and 1 kHz) was used as a stress factor in the last two tests. The lower frequency of staying at the square no. 8 (where was placed manger) were found in the trial group. There were significant differences between groups in the fifth test and in the third day. Frequency of concentrate sniffing was similar as in previous activity. Animals of trial group showed during all tests a shorter feeding of concentrate, differences were in the fifth test and in the second day. There were no differences between groups in frequencies or lengths of staying in square no. 4 where an unfamiliar person was sitting, but slightly higher values were recorded in a control group. Contact behaviour, measured by the frequency and length of sniffing of the person was not different, during the third test level was slightly higher in control group and during next one in the trial group
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