Hematology is an important factor that could be considered
for the fish diet quality assessment. Ologhobo (1992)
reported that the most common blood variables consistently
influenced by diet are the hematocrit (Ht) and hemoglobin
(Hb) levels. Probiotics and prebiotics have been used alone
and together in various animals including the synbiotic, in tilapia
(Abd El-Rhman et al., 2009),