The impact of farrowing room noise on sows’ reactivity to piglets

Authors: CHAPEL, N. - Purdue University; RADCLIFFE, J. - Purdue University; STEWART, K. - Purdue University; LUCAS, J - Purdue University; Lay Jr, Donald

Submitted to: Translational Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/6/2018
Publication Date: 12/13/2018
Citation: Chapel, N.M., Radcliffe, J.S., Stewart, K.R., Lucas, J.R., Lay Jr, D.C. 2018. The impact of farrowing room noise on sows’ reactivity to piglets. Translational Animal Science. 3(1):175-184. https://doi.org/10.1093/tas/txy134.
DOI: https://doi.org/10.1093/tas/txy134

Interpretive Summary: Despite much interest in sow welfare, the impact of the acoustic environment on sow reactivity to her piglets is rarely considered. The objective of this study was to understand the impact of noise produced by mechanical ventilation and other sows on a sow’s reactivity to her piglets. Ventilation noise and noise produced by other sows can affect sow reactivity to her young, however, in which ways remain somewhat inconclusive. Sows will adjust their vocalization behavior based on background noise and may benefit from environments designed to minimize the amount of background sow noise interference. Decreased interference can result in better sow-piglet communication, which could lead to less piglets crushed by sows as vocalizing by piglets is the primary signal sows use during a crushing event. Sows were housed in 1 of 3 environments: room with other sows/piglets and fans, room with only fans, or alone in a room with no fans or other sows/piglets. To test the sows’ responsiveness, piglets were removed from the sow and then returned. The sows’ behavior and vocalizations were recorded. Overall, sows acclimated to the removal and return events with decreased vocalizations and decreased alert behaviors in the second removal and return. Additionally, young sows performed more active behaviors than old sows, indicating that sows may become less interested in or cannot hear their piglets as they age. Finally, there is some indication that ventilation presence influences sow-piglet communication with sows in the room with fans having the loudest calls when compared to sows without ventilation noise, indicating that ventilation noise may be a possible competitor with a sow’s ability to communicate with her piglets.

Technical Abstract: Despite much interest in sow welfare, the impact of the acoustic environment on sow reactivity to her piglets is rarely considered. The objective of this study was to understand the impact of noise produced by mechanical ventilation and other sows on a sow’s reactivity to her piglets. Sows were farrowed in 1 of 3 environments: 1) with 8 other sows exposed to constant fan noise (CON; n = 10), 2) alone with fan noise present (FAN; n = 10), and 3) alone without fans running (QUIET; n = 10). Sows were subjected for 5 min to a piglet removal event (REMOVAL) by an unknown handler twice, at 24 and 48 h post farrowing. During a REMOVAL, sows were observed via video recording for changes in posture, eating and drinking behavior, and head orientation. Audio was recorded to quantify vocalizations by the sow. Once piglets were returned, sows underwent further behavior observations for 10 min (RETURN). Sows were classified as young (2nd and 3rd parity) and old (5th parity and older). The YOUNG sows tended to be Alert (looking toward the handler or their piglets) more during REMOVE than OLD sows (P = 0.07; 2.01 and 1.33, respectively). The FAN sows called the loudest during REMOVAL (P < 0.001) with QUIET sows performing the quietest calls (CON: 72.22 ± 1.06 dB; FAN: 73.61 ± 1.07 dB; QUIET: 67.41 ± 0.99 dB). A narrower bandwidth (P < 0.01) occurred in the first REMOVAL than the second (First: 1,815.6 ± 167.13 Hz; Second: 1,552.0 ± 168.84 Hz). During RETURN, YOUNG sows spent more time sitting than OLD sows (P < 0.01; 7.48 ± 1.6% and 0.91 ± 1.8%, respectively). The QUIET sows tended to have more posture changes during the RETURN with FAN having the least changes (P = 0.06; CON: 1.23 ± 0.4; FAN: 0.44 ± 0.3; QUIET: 1.61 ± 0.4). Finally, sows decreased the amount of time Alert in the second RETURN (P = 0.03; First: 3.9 ± 0.6%; Second: 2.5 ± 0.6%). Overall, sows acclimated to the removal and return events with decreased vocalizations and decreased Alert behaviors in the second REMOVAL and RETURN. Additionally, YOUNG sows performed more active behaviors than OLD sows, indicating that sows may become less interested in or cannot hear their piglets as they age. Finally, there is some indication that ventilation presence has an effect on sow-piglet communication with FAN sows having the loudest calls when compared to sows without ventilation noise, indicating that ventilation noise may be a possible competitor with a sow’s ability to communicate with her piglets.