ARS | Publication request: Essential oils increase weight gain in channel catfish

Submitted to: Global Aquaculture Advocate
Publication Type: Trade Journal
Publication Acceptance Date: July 1, 2011
Publication Date: July 1, 2011
Citation: Peterson, B.C., Bosworth, B.G., Wood, M.L., Li, M.H., Beltran, R. 2011. Essential oils increase weight gain in channel catfish. Global Aquaculture Advocate. 14:80-82.

Interpretive Summary: A trial examined whether matrix encapsulated essential oils (Biomin® P.E.P. MGE) would improve weight gain, specific growth rate (SGR), feed conversion ratio (FCR), and survival in channel catfish. Treatments were: 1. Control (32% crude protein floating commercial diet) and 2. Biomin® P.E.P. MGE (32% crude protein commercial floating diet supplemented with Biomin® P.E.P. MGE at 200 g/ton). Tanks (1,150 L) were supplied with re-circulated pond water and aeration. The fish were fed once a day for twelve weeks and weighed every four weeks. Water quality was monitored throughout the study. At the end of the study, fillets were analyzed for protein and fat. Water temperature and dissolved oxygen averaged 32.9°C and 9.3 mg/L, respectively. Total ammonia nitrogen and nitrite averaged 0.34 and 0.01 mg/L, respectively. By week 8, fish fed Biomin® P.E.P. MGE gained more weight (51.4 ± 1.9 g/fish vs. 37.3 ± 5.1 g/fish) and had a higher SGR (1.8 ± 0.1 vs. 1.5 ± 0.1) compared to controls. At the end of the study, fish fed Biomin® P.E.P. MGE gained more weight (76.9 ± 2.0 g/fish vs. 53.4 ± 3.2 g/fish) and had a higher SGR (1.5 ± 0.1 vs. 1.3 ± 0.1) compared to controls (P < 0.001) (Table 1). In addition, fish fed Biomin® P.E.P. MGE consumed more feed (104.3 ± 3.6 g/fish vs. 79.6 ± 3.0 g/fish) suggesting an increase in feed palatability. There was an improvement in FCR (1.36 vs 1.51) in Biomin® P.E.P. MGE fed fish, although not statistically different. Survival rate (90% vs 89.5%) was similar for both treatments. Fillet composition analysis showed that the amount of fat in the fillets of fish fed Biomin® P.E.P. MGE was lower (16.1% vs 18.7% ) and the amount of protein was higher (79.6% vs 76.5%) compared to controls.

Technical Abstract: We examined the effects of matrix encapsulated essential oils (Biomin® P.E.P. MGE) on weight gain, specific growth rate (SGR), feed conversion ratio (FCR), and survival of channel catfish. Five hundred catfish (32.4 ± 1.7 g/fish) were randomly assigned to two treatments with five replicate tanks/treatment of 50 fish/tank. Treatments were: 1. Control (32% crude protein floating commercial diet) and 2. Biomin® P.E.P. MGE (32% crude protein commercial floating diet supplemented with Biomin® P.E.P. MGE at 200 g/ton). Tanks (1,150 L) were supplied with re-circulated pond water and aeration. The fish were fed once a day to apparent satiation for twelve weeks and weighed every four weeks. Water quality was monitored throughout the study. Water temperature averaged 32.9°C while dissolved oxygen averaged 9.3 mg/L. Total ammonia nitrogen and nitrite averaged 0.34 and 0.01 mg/L, respectively. By week 8, Biomin® P.E.P. MGE fed fish gained more weight (51.4 ± 1.9 g/fish vs. 37.3 ± 5.1 g/fish) and had a higher SGR (1.8 ± 0.1 vs. 1.5 ± 0.1) compared to controls (P < 0.03). By the end of the study, Biomin® P.E.P. MGE fed fish gained more weight (76.9 ± 2.0 g/fish vs. 53.4 ± 3.2 g/fish) and had a higher SGR (1.5 ± 0.1 vs. 1.3 ± 0.1) compared to controls (P < 0.001). In addition, Biomin® P.E.P. MGE fed fish consumed more feed (104.3 ± 3.6 g/fish vs. 79.6 ± 3.0 g/fish). FCR and survival were not different between treatments at either 8 or 12 weeks. The results show that fish fed Biomin® P.E.P. MGE consumed more feed and gained more weight. The addition of Biomin® P.E.P. MGE to catfish diets may prove beneficial in improving palatability of feed as well as improving growth of channel catfish.