Abstract:
Wheat grass juice (WGJ) is an extract of young wheat plantlets (Triticum aetivum L.) used
worldwide for its health related properties. In this study, the following feeds containing WGJ were
tested on common carp (Cyprinus carpio L.): Control (C), WGJ1% (V1), WGJ2% (V2) and WGJ4%
(V3) w/w. Fish with an average initial weight of 102 g/individual were grown in a recirculating
aquaculture system. The results showed that WGJ had stimulatory effects on growth performance.
Accordingly, final body weight increased by 11% at V1, 39% at V2 and 23% at V3, while other
indices (feed conversion ratio, specific growth rate, relative growth rate, protein efficiency ratio,
and condition factor) were unaffected. Body composition analyses revealed a significant decrease
in fat content at V2 and a significant increase in collagen and ash at the same variant, while the
protein content was unmodified. Regarding the blood profile, significant increases in the content of
albumin, globulin, total protein, and calcium were recorded in the variants with WGJ. The positive
results of WGJ on carp can be attributed to its biochemical composition, which is rich in chlorophyll
(4.71 mg mL1), total phenols (164 g mL1 gallic acid equivalents), and high antioxidant activity
(67% inhibition of DPPH 2,2-diphenyl-1-picrylhydrazyl). The results suggest WGJ can be used as a
promising feed additive for common carp.