This study involved 120 pike, Esox lucius, captured from Anzali wetland. Parasite fauna were identified in captured fish. Also, changes of haematological parameters were compared both infected and uninfected fish. Parasitological inspections revealed the following infestations: Skin: Lernea cyprinacea, Argulus foliaceus (Crustacean) and Tricodina sp. (Ciliatea). Gill: Dactylogyrus sp. (Digenea) and Tetraonchus monenteron (Monogenea). Eye: Diplostomum spathaceum (Digenea). Gut: Eustrongylides exises, Rhipdocotyle illense, Raphidascaris acus (Nematode), Corynosoma Strumosum (Acanthocephala). Most prevalence and intensity were related to Eustrongylides exises and Rhipdocotyle illense. Following haematological parameters were evaluated: haematocrit, haemoglobin concentration, erythrocyte and leukocyte counts, mean cell volume (MCV), mean cell haemoglobin, mean cell haemoglobin concentration lymphocytes, monocytes and eosinophils. Significant difference was found for MCV between infected and uninfected fish.

A parasitological investigation was done on 175 specimens. Infections of A. brama orientalis were analyzed according to the age and sex. The fish also were examined for evaluation changes of haematological parameters in relation to parasitic infection. Four parasites were found, including-Caryophyllaeus laticeps and Ligula intestinalis (Cestoda), Diplostomum spathaceum (Platyhelminthes) and Trichodina sp. (Ciliophora). Among identified parasites maximum prevalence and mean intensity were related to Ligula intestinalis and Caryophyllaeus laticeps respectively. The values of prevalence and mean intensity showed significant differences among ages. Our results revealed prevalence, mean intensity and abundance had not significant difference between males and females. Parasite infection provoked reduction (P \ 0.05) in haematocrit, mean cell volume and lymphocyte. On the other hand, significant increase (P \ 0.05) in white blood cell (WBC), mean cell haemoglobin concentration and neutrophil in blood of infected fish was observed. Significant differences were detected for the WBC, lymphocyte and neutrophil (infected versus uninfected by Trichodina sp., Diplostomum spathaceum and Caryophyllaeus laticeps). In addition to WBC and lymphocytes, significant change was observed for the haemoglobin (Hb) (infected versus uninfected by Ligula intestinalis).

A total of 120 common carp Cyprinus carpio L. with average weight 20.45±1.24 gm/fish were assigned randomly into five groups of three replicates for each group, each replicate included 8 fishes. The fish were fed for 90 days on five diets that equal in isonitroenons 24.16% and isocaloric 1408.88 MJ/kg. Diet for control T1, local probiotic Iraq probiotic added at levels 5g/kg for diet T2, local probiotic added at 5g/kg from diet+5g/kg prebiotic which include fructo-Oligosacchardes FOS for diet T3, imported probiotic which include Enterococcus faecium added at 2g/kg diet for diet T4, imported probiotic which include E. faecium added at 2g/kg diet+2g/kg per diet prebiotic which include FOS for diet T5. The results showed there were significant distinction for T5 p<0.05 in growth parameter and food conversion and sufficiency rate FCR and FER and apparent coefficient digestibility ACD, there were no significant different between T5 and T4. The results of blood biochemical examination showed significant distinction for T4 from T1 and T2 in packed cell volume (PCV) and Hemoglobin Hb, there were no significant different between all treatment in erythrocyte and leukocyte count RBC and WBc.