Improvement of Growth properties, Survival, hematological-humoral immunity factors and intestinal bacterial density of brown trout (Salmo trutta caspius Kessler, 1870) affected by different levels of Beta-Plus as probiotic

Document Type : Research Paper


1 MSc Department of Fisheries, Gillan Science and Research Branch, Islamic Azad University, Rasht, Iran

2 Associate Prof. Department of Fisheries, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran

3 Assistant Prof. Department of Fisheries, Lahijan Branch, Islamic Azad University, Lahijan, Iran


Effcts of Beta-plus as probiotic on growth properties, survival, hematological factors and intestinal bacterial density of brown trout were investigated. Numbers of 585 juveniles during 3 months have studied with 105±5 in weight, 15 basins with a density of 39 fish per 1,500 liters. Different level of Beta-plus were used ranged as 0, 0.5, 1, 1.5 and 2Kg per ton of food) with 3 repeats in a completely randomized design. The results showed according to adding the probiotics in feed, growth properties such as PBWI, BWf, FCR and SGR were improved (P<0.05). In addition, fish fed with 1.5Kg/T Beta-plus showed best performance in Caspian Sea Brown trout in comparison to other treatments. Parameter of WBC had not any different among blood parameters (P>0.05), while the probiotic reduced amounts of RBC, Hb and HTC (P<0.05). Also, microflore bacteria counts were increased due to Beta-plus (P<0.05) statistically, but there was no different in Immunoglobin M (IgM) between treatments, as a humoral immunity parameter. Thus, supplement of Beta-plus intruduced as a growth stimulator in culture of Caspian Sea salmonid fish.