Effect of the probiotic Entrococcus faecium on hematological and non-specific immune parameters and disease resistance in zander (Sander lucioperca)

The current study evaluated effects of dietary administration doses of Entrococcus faecium on the hematological factors, and disease resistance of Sander lucioperca against Aeromonas hydrophila infection. Fish were fed with dietary administration containing E. faecium doses including of (1010, 108CFU/ g) for diet A1 and A2, respectively in a commercial diet as basal diet were used for 6 weeks. The control group was basal diet with serum. The hematological and immunity parameters were measured and fish were challenged with A.hydrophila (4.5×108CFU/mL). Fish were monitored daily and the mortality rates were recorded over 8 days post – challenge. The results indicated that HCT in A1 treatment (1010CFU/g) had significantly increased in compare to the control and A2 (108 CFU/g) treatments (p<0.05).  MCV in A1(10 10CFU/g) and control groups were significantly higher than A2 (108 CFU/g) Treatment (p<0.05). However, other parameters e.g. RBC, HB, MCH, MCHC had no significant different. The serum lysozyme, alternative complement activity (ACH50) and IgM levels were significantly enhanced in dietary administration E. faecium(108,1010CFU/g) in feeding period. Survival rate of fish by dietary administration E. faecium (1010CFU/g) was significantly higher (p<0.05) than the other groups (86.6%).