author(s)
Nesara KM, Jayaraj EG and Sandeep CV

abstract
The present study was carried out to evaluate the influence of dietary supplementation of probiotic and organic acid on immunological parameters of Labeo rohita. The feeding trial was conducted for about 120 days with fingerlings of length and weights ranging from 8.55-9.21cm and 5.55-6.65g respectively. The fishes were administered with diets containing different level of Lactobacillus plantarum (LP) (10⁸ CFU/g) and citric acid (CA) (3%) individually and in combination 10⁸ CFU/g LP+ 3% CA and without Lactobacillus plantarum and citric acid served as control. Higher super oxide anion production was evident in Lactobacillus plantarum (10⁸ CFU/g) followed by citric acid (3%) individually while LP+CA (combination) showed significant difference between the groups (P<0.05). The total serum protein was higher in LP+CA followed by LP alone, citric acid alone and control with significance (P<0.05). Similarly, lysozyme activity also showed significant difference (P<0.05) but observed to be higher in LP alone followed by LP+CA, citric acid alone and control diet. The fishes challenged to Aeromonas hydrophila at the end of growth study showed significant difference in cumulative survival in different treatment groups. However, highest cumulative percent of survival and relative percent survival was evident in fish fed with LP+CA incorporated diets.