The Role of Temperature and Litter Type in the Development of Breast Buttons in Turkeys ,

Abstract

Two 16-wk experiments examined effects of temperature and litter on breast buttons of heavy tom turkeys. In Experiment 1, turkeys were reared on coarse or fine sawdust litter and finished under warm or cool conditions from 6 to 16 wk. In Experiment 2, turkeys were reared on sawdust or newspaper litter and brooded from 0 to 9 wk under warm or cool conditions. Breast buttons first appeared between 4 and 8 wk, and the incidence increased between 8 and 16 wk although buttons could heal and disappear within a 4-wk period. Breast buttons were associated with higher body weights at 8 and 12 wk, and reduced feather cover over the keel at 8, 12, and 16 wk (P < .05). At 12 wk, cooler temperatures resulted in larger breast buttons in Experiment 1 and a higher breast button incidence in Experiment 2 (P < .05), with no effect on feather cover over the keel. The breast button incidence at 16 wk was higher on coarse (41.4%) than fine sawdust (21.3%), and higher on newspaper (53.6%) than sawdust litter (23.8%, P < .0l). Higher 16-wk breast button incidence was associated with poorer carcass grades. At 15 wk, litter moisture was 14% in Experiment 1 and 25% in Experiment 2. The results indicate that a high breast button incidence can occur in the absence of sharp litter particles and that wet litter is not a prerequisite for the development of breast buttons. Breast button incidence can be reduced and carcass quality improved by avoiding coarse and hard-packing litter materials. Cooler temperatures during rearing may result in increased downgrading due to breast buttons in turkeys slaughtered at broiler weights.