Feather meal as a nonspecific nitrogen source for abdominal fat reduction in broilers during the finishing period

Earlier studies have shown that excessive abdominal fat deposition in broilers can be overcome by feeding feather meal (FM) during the finishing period (7 or 14 days prior to slaughter). Studies were conducted to determine if the observed fat reduction in FM-fed birds was due to factors other than supplying excess protein. The FM was added at levels of 4, 6, and 8% and glycine at levels of .125, .25, and .5%, similar to amounts contributed by corresponding levels of FM. Corn-soybean diets were also formulated at protein levels corresponding to those of FM diets. All experimental diets were fed from 35 to 49 or from 42 to 49 days of age. There were no significant differences in weight gain and feed efficiency of treatment and control groups during the study. The addition of glycine resulted in a significant (P less than .05) reduction in abdominal fat content and appeared to be partially responsible for the observed reduction in FM-fed birds. Increasing the dietary protein level also significantly (P less than .05) reduced abdominal fat deposition regardless of protein source. The study indicates that lower quality protein sources such as FM can be effectively used as a nonspecific nitrogen source for reducing abdominal fat deposition during the finishing period.