<b>Enriching Fish Scale Flour with Squid Oil and Freshwater Pangasius Catfish Oil: Impact on Proximate Composition, Fatty Acids, and Amino Acids</b>

Fish scale waste is abundant across local markets in Indonesia, including from the annual mass mortality of carp (Cyprinus carpio) in Lake Maninjau, but lacks optimal usage as an economical feed ingredient for fry. Therefore, this study aims to determine the proximate composition, fatty acids, and amino acids in fish scale flour enriched with marine squid oil (MSO) and freshwater pangasius catfish oil (FPO) at different doses of 0, 2, 4, and 6%. The proximate composition was analyzed using the standard AOAC method, while amino and fatty acids were assessed with high-performance liquid chromatography (HPLC) and gas chromatography-spectrometry (GC-MS). The results showed that fish scale flour enriched with MSO and FPO at different level had protein ranging from 67.25 - 67.75% and 67.72 - 68.27% as well as fat content of 0.23 - 2.38% and 0.23 - 2.32%, respectively. Additionally, both flour variants contained 11.64 - 16.77% and 33.92 - 40.03% saturated fatty acids (SFAs), 6.60 - 10.25% and 15.07 - 16.08% monounsaturated fatty acids (MUFAs), 10.13 - 20.20% and 4.32 - 4.16% polyunsaturated fatty acids (PUFAs), as well as 56.44 - 59.09% and 65.01 - 66.48% total free amino acids (FAAs), respectively. The higher levels of PUFAs, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the flour enriched with MSO signified that this feed ingredient comprised a healthier fat profile and was more optimal in supporting fry growth, thereby benefiting the general fish health.