Self- and conspecific-directed pecking behavior of commercial Pekin ducks

Abstract

Injurious pecking behavior affects commercial Pekin duck welfare, but little information is available regarding the characteristics thereof. This study investigated self- and conspecific-directed pecking behavior of ducks, including 1) the prevalence, frequency and duration, 2) age-related changes in pecking and preening behavior, and body locations affected; 3) influence of time of day and location within the barn; and 4) occurrence of feather removal and feather eating. Behavior of two commercial flocks was video-recorded at 20–22 d (Period 1), 27–29 d (Period 2), and 34–36 d (Period 3) and analyzed using scan (n = 340 ± 91 ducks/flock per observation time point) and focal (n = 144 observation periods/flock) animal sampling. The percentage of ducks performing pecking behavior (gentle feather pecking (%GFP), severe feather pecking (SFP), aggressive pecking (AGGP) and self-picking (SELFP)) was determined every 30 min (09:00 h-15:00 h). Randomly selected focal ducks were observed for 30 min (09:45 h-10:15 h and 13:45 h-14:15 h) to determine durations and frequencies of pecking and preening behavior and the occurrence of feather removal and feather eating. Scan sampling data and focal behavioral durations were analyzed using PROC MIXED; behavioral frequencies were analyzed using PROC GLIMMIX (SAS 9.4). SFP, AGGP and SELFP were combined into one category, other pecking (OP), for analysis. GFP was observed most frequently, SFP and AGGP occurred less frequently, and SELFP was rarely observed. Feather removal (13 times) and feather eating (7 times) occurred infrequently. GFP frequency, duration and GFP% increased from Period 1 to 2 (P < 0.01), then declined from Period 2 to 3 (P < 0.01). Preening frequency and duration similarly changed with age (P < 0.01). OP frequency (P = 0.03) and duration (P = 0.03) were higher in Period 2 than Period 1. Body locations affected by GFP included the tail, wings and back. Little injurious pecking was observed; GFP between conspecifics was the most frequently observed behavior. Age was a major factor affecting the performance of pecking behavior, which peaked at Period 2 and was most frequently directed at the tail, wings and back. Further research is needed to examine seasonal effects and other factors influencing injurious pecking of ducks.