However, the result in the current study disagrees with that of McFarlane and Curtis (1989), who reported that heterophil to
lymphocyte ratio was unaffected by continuous noise for seven days (95 dB versus 80 dB)
in broiler chicks 2-week-old. Similarly, McFarlane et al. (1989a) indicated that behavioral
traits (standing, lying, drinking, and eating) were not influenced by noise, although
McFarlane et al. (1989b) showed that noise affected pathologic traits, suggesting that it
may be detrimental to the bird’s health even though behavioral measures do not show any
obvious adverse effects.