# Effects of Corn Fermented Protein as a Primary Protein Source on Growth Performance, Feed Utilization Efficiency, Hemolymph Biochemical Parameters, and Physiological and Digestive Gene Expression of Pacific White Shrimp (Litopenaeus vannamei)

## TL;DR

This study shows that corn fermented protein can replace traditional protein sources in shrimp feed without harming growth or health.

## Contribution

The study demonstrates the feasibility of using corn fermented protein as a primary protein source in shrimp feed without adverse effects.

## Key findings

- Replacing fish meal, soybean meal, and corn protein concentrate with corn fermented protein did not significantly affect shrimp growth or feed efficiency.
- No signs of gut inflammation or digestive enzyme disorders were observed in shrimp fed with corn fermented protein.
- Net phosphorus retention showed significant shifts, but other hemolymph and physiological indicators remained stable.

## Abstract

This study aimed to determine the effect of replacing fish meal (FM), soybean meal (SBM), and corn protein concentrate (CPC) in an equal ratio with corn fermented protein (CFP) on Pacific white shrimp, Litopenaeus vannamei growth, feed utilization efficiency, hemolymph parameters, and physiological gene expression. A green water recirculation system was employed with a stocking density of 30 shrimp per tank (~35 shrimp/m2) and an initial weight of 0.216 ± 0.007 g (mean ± standard deviation). Six experimental diets were investigated over 8 weeks. The primary protein sources in the basal diet were systematically replaced (0% – 25% diet) with CFP. No significant changes in shrimp growth indicators were found between shrimp reared on the various diets (p  > 0.05). We found few significant differences in feed utilization efficiency (p  > 0.05), but especially for feed conversion ratio (FCR; p = 0.372) shifts in net phosphorus retention (PR; p  < 0.001) were significant. Physiological gene expression analysis revealed no signs of gut inflammation or digestive enzyme disorders (p  > 0.05). At the same time, the hemolymph index exhibited similar patterns with no statistically significant outcome (p  > 0.05). The results showed that, under a setting with natural productivity, different replacement levels did not impair the growth response, feed consumption, physiological gene expression, and hemolymph indicators of Pacific white shrimp when appropriately balanced with other protein sources. The results demonstrated the feasibility of replacing the primary protein source with CFP in practical feed applications. Overall, using CFP in shrimp feed formulation resulted in a good growth rate with no adverse effects.