Nutritional evaluation of toasted Mucuna utilis seed meal and its utilization in the diet of Clarias gariepinus (Burchell, 1822)

ABSTRACT

The value of toasted Mucuna utilis seed meals was investigated in this study by evaluating the nutritional profile and the utilization of the processed seeds in isonitrogenous (35% CP) and isocaloric diets (17 kJ g−1) for African catfish Clarias gariepinus (Burchell 1822). Toasting the M. utilis seed significantly reduced the levels of tannins, phytate, trypsin, and hemagglutinin in the seeds. However, protein, gross energy, arginine, histidine, and valine were increased (P ≤ 0.05). The processed seed was then used to formulate five experimental diets by progressively increasing its inclusion (by 50 g kg−1) from zero up to 200 g kg−1. A sixth diet was also formulated with raw M. utilis included at 200 g kg−1 to determine the efficacy of the processing method applied in this study. Fifty fingerlings of C. gariepinus (2.02 g ± 0.08) stocked in 18 hapas measuring 1 × 1 × 1 m³ were then fed the diets for 56 days. The growth of C. gariepinus fingerlings was significantly improved by the addition of the toasted M. utilis seed meal. However, fish fed the diet containing 200 g kg−1 of raw M. utilis had poor growth with higher mortality (35%). Estimation of the feeding cost using the diets revealed reduction in production cost of fish with the inclusion of toasted M. utilis seed meal. It was concluded that toasting significantly improved the nutritional quality of this unconventional feedstuff, allowing better utilization at up to 200 g kg−1 inclusion level in the diet of African catfish C. gariepinus.

KEYWORDS:

• African catfish
• ANFs
• carcass
• NCFR
• nutrient utilization

Acknowledgments

The authors are deeply thankful to all laboratory officers who assisted in the analysis of the feed, diet, and carcass and in data collection. We are also grateful to the administration of the University of Agriculture, Makurdi, and the University of Jos for making available facilities for this research.

Funding

This study was financed by a grant from the West African Agricultural Productivity Programme (WAAPP) for the Broodstock and Fingerlings Multiplication Project, which was executed in the Department of Fisheries and Aquaculture, University of Agriculture, Makurdi, Benue State, Nigeria.

Additional information

Funding

This study was financed by a grant from the West African Agricultural Productivity Programme (WAAPP) for the Broodstock and Fingerlings Multiplication Project, which was executed in the Department of Fisheries and Aquaculture, University of Agriculture, Makurdi, Benue State, Nigeria.