Effects of lactoferrin and Lactobacillus rhamnosus PTCC 1637 on some physiological parameters and histology of gut and ovary of Carassius auratus brood stocks

This study was conducted to evaluate the effects of lactorerrin andLactobacillus rhamnosus PTCC 1637for 120 days on some physiological parameters and histology of gut and ovary of Carassius auratus brood stocks (12.21±0.50 g). Experimental treatment contained four treatments: the first treatment: L. rhamnosus PTCC 1637 (106 CFU / g feed), the second treatment: Lactoferrin (200 mg / kg feed), the third treatment: combined diet with L. rhamnosus PTCC 1637 and lactoferrin and a control without probiotic and lactoferrin, in triplicates. The results showed that Hepatosomatic Index (6.05±1.02) and Gastro somatic Index (6.97±1.07) increased significantly in first treatment (P<0.05). The highest Gonado somatic Index (19.58±0.82) was observed in first treatment. Histological studies indicated that the length (330 µm), the width (109 µm) and the absorbance surface area (112946 µm2) of villi in probiotic treatment were more than the others (P<0.05). At the end of the trial, the ovaries of control, first and second treatment reached stage V while the ovaries of combined treatment were at the early stage IV. According to results, application of Lactobacillus rhamnosus PTCC 1637 due to absorbance surface enhancement of the villi could be an appropriate choice for feed efficiency improvement in C. auratus.