Dietary Methionine requirements for juvenile Florida Pompano (Trachinotus carolinus)

Authors: CORBY, TRENTON - Auburn University; NGO, TRINH - Auburn University; RICHE, MARTY - Harbor Branch Oceanographic Institute; DAVIS, ALLEN - Auburn University

Submitted to: Journal of Marine Science and Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2024
Publication Date: 7/18/2024
Citation: Corby, T., Ngo, T., Riche, M., Davis, A. 2024. Dietary Methionine requirements for juvenile Florida Pompano (Trachinotus carolinus). Journal of Marine Science and Engineering. 12(7):1206. https://doi.org/10.3390/jmse12071206.
DOI: https://doi.org/10.3390/jmse12071206

Interpretive Summary: Fish, particularly those that are carnivores such as Florida pompano, have traditionally been fed diets containing fish meal. However, there has been a move to plant-based diets as the use of fish meals has been deemed unsustainable. However, plants are deficient in some amino acids needed to support the growth and well-being of many fish. Methionine is considered an essential amino acid because animals can’t produce it and must get it from the diet for growth, health and well-being of the animal. Eight diets using soybean meal, poultry meal, and red lentil meal were supplemented with the essential amino acid Methionine ranging from 0 to 0.7% of the diet. The diets were fed to Florida pompano for 56 days to identify the Methionine requirement needed for optimal growth and efficiency. After applying the data to several models, following the guidance of the model that fit the best, it was determined that the Methionine requirement for Florida pompano is 0.74% of the diet or 1.7% of the protein. This report supports the growth of a growing marine finfish aquaculture industry to enhance food safety and security of the American public.

Technical Abstract: A 56-day feeding trial was conducted to evaluate the quantitative methionine requirements in the diets of Florida pompano (Trachinotus carolinus). Eight practical diets using soybean meal, poultry meal, and red lentil meal as the primary protein sources were formulated using graded levels of methionine supplement (0 to 0.70 g/100 g diet). Groups of 15 juvenile Florida pompano (4.04 ± 0.05 g) were size-sorted and placed into one of 40 glass aquaria (132 L) with five replicates per diet. Significant differences (p = 0.05) were observed in overall biomass, mean weight, weight gain, thermal growth coefficient (TGC), and feed conversion ratio (FCR). To estimate the dietary methionine requirement, a series of statistical models, including the one-slope broken line model (BLM1), two-slope broken line model (BLM2), broken quadratic model (BQM), and four-parameter saturation kinetic model (SKM-4) were used to assess mean weight, weight gain, TGC, apparent net protein retention (ANPR), and methionine retention (MR). The model selection showed that BLM1 fit the data best for MW and TGC, SKM-4 for PWG and ANPR, and BQM for MR. Based on these results, a minimum dietary methionine requirement of 0.68% of the diet or 1.70 g/100 g protein is recommended.