NR 26. Enhancing protein utilization from feather meal

Abstract

The objective of this work was to develop novel ammonia reactor processing conditions to treat feather meal which will extend the use of feather meal protein products for animal feeding. Liquid anhydrous ammonia was added to 60 g-samples and temperature was rapidly elevated to the desired temperature. After desired treatment time, pressure was suddenly released and samples allowed to air-dry overnight. In situ ruminal solubility (one minute in the rumen) and digestibility (3, 6, 12, 24 and 48 h in the rumen) were determined by the dacron satchel method using a cannulated steer. Kjeldahl was used for crude protein determination. Feather meal had 10 % moisture content (w.b.), 88 % crude protein, 1.4 % crude fat and 6.2 % ash. Protein solubility greatly increased (7 to 23 %) with PDA for 50% moisture-samples compared to the control (P<.05). There were also significant differences in protein solubility (P<.05) with PDA at 75 and 90 ºC for the 50 % moisture-samples. PDA processing greatly enhances the potential use of feather meal as a protein source. If treated feather meal is fed to a ruminant, more than 20 % of the protein will be immediately soluble and thus available to the rumen microorganisms, providing ammonia for microbial function. Digestibility of protein for 10% moisture-samples was not significantly different (P>.05) from the control (untreated feather meal). However, protein digestibility greatly increased for PDA-treated 50 % moisture FM. Protein digested at 48 h was increased from 24% (control) to 48 % with selected treatments. Significant effects were also found for temperature and ammonia loading (P<.05). These results show that PDA can be used to increase the utility of feather meal protein.