A preliminary study was conducted to determine if diets supplemented with 1.5% catfish oil (CFO), or 1.5% menhaden oil (MHO) improved fish condition prior to winter fasting. Fish were maintained in 1,200 L polypropylene tanks supplied with continually exchanged pond water. Fifteen hundred channel catfish juveniles (~20 g) were equally distributed in 15 tanks in a completely randomized block design (n=5) , and each tank were assigned to either the control diet ( commercial feed), or diets supplemented with CFO or MHO. Fish were fed experimental diets for 8 weeks and feeding was suspended when water temperature fell below 150C . A subsample of 10 fish from each tank were obtained to compute the conditional indices. The fish remainders from each experimental unit were pooled, ground, and homogenized to measure the whole-body proximate composition. No significant differences were detected for weight gain, survival, hepatosomatic index, and whole-body proximate composition. However, fish fed CFO presented a significantly higher feed efficiency compared to the control diet. Intraperitoneal fat (IPF) was also statistically affected by dietary treatments, with catfish fed CFO presenting the highest IPF, followed by fish fed MHO with intermediate values. Fish fed the control diet had the lowest IPF ratio. While fish fed CFO had the highest IPF ratio, they also presented more efficient protein conversion compared to fish fed control diets. This suggests supplementation of CFO aided protein-sparing effects and prevented amino acids from being used as metabolic substrates . More investigation is warranted to determine how CFO improves protein utilization and whether supplemental lipids can limit protein catabolism during winter fasting.