The Impact of Acute Loud Noise on the Behavior of Laboratory Birds

Abstract

Husbandry procedures and facility settings, such as low-frequency fire alarms, can produce noises in a laboratory environment that cause stress to animals used in research. However, most of the data demonstrating harmful effects that have, consequently, led to adaptations to management, have largely come from laboratory rodents with little known of the impacts on avian behavior and physiology. Here we examined whether exposure to a routine laboratory noise, a low-frequency fire alarm test, induced behavioral changes in laboratory zebra finches (Taeniopygia guttata). Twenty-four breeding pairs of zebra finches were randomly selected and exposed to the low-frequency fire alarm (sounding for 10-20 s) or no noise (control) on separate test days. All birds were filmed before and after the alarm sounded and on a control day (without the alarm). The zebra finches decreased their general activity and increased stationary and social behaviors after exposure to the alarm. Brief exposure to a low-frequency alarm disrupted the birds' behavior for at least 15 min. The induction of this behavioral stress response suggests that low-frequency sound alarms in laboratory facilities have the potential to compromise the welfare of laboratory birds.

Keywords: animal welfare; avian husbandry; bird; noise stress; passerine; zebra finch (Taeniopygia guttata).

Figure 1

Timeline of experimental procedure. Birds subjected to Treatment 2 were transported to the experimental room for acclimatization on day 4 of the experiment for Treatment 1 birds. On day 7 all birds were returned to the colony rooms and new pairs were brought in. This staggered procedure was repeated until 24 pairs were filmed twice (for alarm and control).

Figure 2

Back (A) and aerial (B) views of the layout of the experimental cage including the: (a) water bowl or hopper; (b) food bowl or hopper; (c) oyster shell grit bowl, (d) cuttlefish bone, and (e) mineral block.

Figure 3

Mean (±95% CI) sound pressures observed in the experimental room for the 30 min prior to the stimulus interval and 30 min after, for both the alarm and control days, with birds present and absent.

Figure 4

Time series of mean sound pressures (dBA) measured on each of the test days (alarm and control) and represented for days when birds were present and absent of the experimental room. Time axis shows a timescale in minutes of intervals before and after the stimulus interval (alarm and control). Negative numbers correspond to the minutes before the stimulus started (A) and positive values correspond to minutes after the stimulus interval finished (B).

Figure 5

Mean (±95% CI) sound pressures observed in the experimental room for the intervals corresponding to the 15 min immediately before the stimulus (15 BEFORE) and 15 min immediately after (15 AFTER).

Figure 6

Mean (±95% CI) differences in time the birds spent (in seconds) performing different behaviors on the alarm and control days. Differences were calculated by subtracting the total duration of each behavior in the 15 min immediately before the stimulus interval from the duration observed on the 15 min subsequently after the stimulus. Behaviors marked with an asterisk *showed a significant difference (P < 0.05) on the behavioral pattern observed after the stimulus between the test days.

Figure 7

Estimated marginal means (±SE) for durations (in seconds) of (A) activity, (B) stationary, (C) social behaviors, (D) preening, (E) foraging, and (F) brooding behaviors before the stimulus (BEFORE) and in 5-min sample intervals after (5A = 0–5 min; 10A = 5–10 min; and 15A = 10–15 min) for both the alarm exposed and control groups. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001.