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Abstract

Cannibalism is a major problem for commercial production of Muscovy ducks (Cairina moschata). Surprisingly little is known about the ontogeny of cannibalism in ducks or how to reduce/prevent the problem in a welfare-friendly way. The preventative method typically used by the industry is bill-trimming, which causes acute pain. We hypothesised that cannibalism in Muscovy ducks is a form of redirected foraging, and therefore investigated the effects of different types of environmental enrichment designed to promote foraging behaviour on general activity patterns and the ontogeny of cannibalism. Groups of 17 bill-intact female Muscovy ducklings were randomly assigned from day-old to one of three treatments (5 replicate groups/treatment): (1) water-enriched treatment (water + plastic strings, water + plastic objects + gravel, water + grain mixture, and pure water), (2) feed-enriched treatment (corn silage, alfalfa, grain mixture + gravel, and Astroturf mats + grain mixture + occasionally mealworms), and (3) control (empty troughs). Floors were covered with wood shavings, and feed and water were available ad libitum.Behaviour was recorded during daylight hours on days 7, 11, 14, and 18 of age. Water- and feed-enriched ducklings foraged significantly more than control ducklings and spent significantly less time inactive during the observations. There were no significant differences between water- and feed-enriched ducklings on these measures, or between any of the treatments for preening and locomotion. Water-enriched ducklings used their enrichments significantly more than feed-enriched ducklings. Although time spent foraging was increased in both the water- and feed-enriched ducklings, cannibalism developed in all treatments beginning at 15–17 days of age. At the end of the experiment (35 days of age), there was no significant difference among treatments in the total number of ducklings with injuries inflicted by cannibalism. Feather pecking was also observed in all three treatments, but the frequency was significantly higher at some ages in the control groups than in the water- and feed-enriched groups. Thus, our findings do not support the hypothesis that cannibalism in Muscovy ducks develops from an unfulfilled motivation for foraging.