Utilization of a by-product from the Jatropha biodiesel industry as a fish meal replacer in common carp Cyprinus carpio L. diets

ABSTRACT

Detoxified Jatropha kernel meal (DJKM) was created through heat and solvent extraction and replaced fish meal (FM) at 0% (C_ontrol), 50% (J₅₀), or 62.5% (J_62.5) in common carp Cyprinus carpio fingerling (initial mean weight ± SD; 22 ± 0.12 g) diets over 16 weeks. Growth performance and feeding efficiencies were similar (P > 0.05) among groups, but nutrient digestibilities and digestive enzyme activities were significantly higher (P < 0.05) in C_ontrol than others. The slightly lower growth and significantly lower nutrient digestibility in carp fed DJKM indicates a need to improve the nutritive value of DJKM as a promising and sustainable FM alternative.

KEYWORDS:

• Common carp
• Jatropha curcas
• kernel meal
• fish meal replacer
• hematology

Acknowledgments

We gratefully thank Hermann Baumgärtner and Beatrix Fischer, the technical staff of our laboratory, for their help in data analysis. We would like to thank Dr. Helga Brehm from the Institute of Anatomy and Physiology (460a), University of Hohenheim, Germany, for her help in the hematological study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Bundesministerium für Bildung und Forschung (BMBF), Berlin, Germany.