Improving Energy Utilization and Digestibility in Sheep through Calcium Hydroxide-Protected Lemuru Fish Oil

This study evaluated the effects of calcium hydroxide-protected Lemuru fish oil on the in vitro rumen and post-rumen digestibility of sheep feed. Lemuru fish oil, rich in omega-3 fatty acids such as EPA and DHA, was supplemented at varying inclusion levels (0%, 5%, 7.5%, 10%, and 12.5%) with and without calcium hydroxide protection. Results showed that fish oil protection significantly (P < 0.01) improved dry matter, organic matter, crude fiber, and crude protein digestibility particularly in the post-ruminal phase. However, increasing the inclusion level of fish oil reduced digestibility across most nutrients, especially at 12.5%. Crude fat digestibility was higher in the unprotected treatment in the rumen but improved post-ruminally in the protected treatment due to better enzymatic utilization. These findings suggest that calcium hydroxide protection enhances the nutritional benefits of Lemuru fish oil while minimizing its negative effects on rumen fermentation, making it a promising strategy for improving ruminant feed efficiency.