THE INFLUENCE OF SYNBIOTIC ON GROWTH AND EXPRESSION OF GH, GHR1 AND IGF-I GENES IN Oreochromis niloticus L FINGERLINGS

M.S.M. HASSAAN¹*, M.M.A. MOUSTAFA², H.A.S. EL-GARHY³, M.H. REFAAT^4
1Fish Nutrition Research Laboratory, National Institute of Oceanography and Fisheries (NIOF), Cairo, Egypt.
²Genetics Department, Fac. of Agriculture, Benha University, Qalubia, Egypt.
³Genetics Department, Fac. of Agriculture, Benha University, Qalubia, Egypt.
⁴Genetics Department, Fac. of Agriculture, Benha University, Qalubia, Egypt.
* Corresponding Author : Mohamed_shaban200065@yahoo.com

Received : 15-03-2015     Accepted : 14-04-2015     Published : 10-06-2015
Volume : 6     Issue : 1       Pages : 176 - 182
J Fish Aquaculture 6.1 (2015):176-182

Keywords : Synbiotic, growth, gene expression, Oreochromis niloticus
Academic Editor : Erchao Li, Dr Cheng-hao Tang, Mahmoud Abdelghagffar Emam
Conflict of Interest : None declared

A combination of probiotics and prebiotics as synbiotics allows assessing their synergistic effects. This study evaluated the effect of synbiotic (Lactobacillus acidophilus and fructooligosaccharides+mannan oligosaccharides, FMOS) on growth, hematological parameters, plasma hormonal, and genes expression in Oreochromis niloticus. A total of 600 O. niloticus of an average initial weight ranged from (4.96 to 5.96 g) was divided into four experimental groups for 84 days. Four basal diets Diet 1 (control), Diet 2, Diet 3 and Diet 4 were formulated to contain four levels of L. acidophilus (0.00, 0.42×107, 0.84×107 and 1.35×107CFU g-1) respectively, each level supplemented with 1% FMOS except of the control diet. O. niloticus fed diet supplemented with synbiotic showed significant (P<0.05) increases in growth and feed utilization. The highest final body weight, best feed conversion ratio, protein efficiency ratio and best chemical composition were obtained by the fish fed synbiotic Diet 3. Supplementation with synbiotic significantly increased in hematological parameters, growth hormone (GH) and insulin-like growth factor-I (IGF-I). The highest expression of GH and GHR1 were detected in liver of fish fed Diet 3. However, IGF-I was down regulated in liver of fish fed Diet 2 and Diet 4 whereas, IGF-I mRNA level in liver of fish fed Diet 3 up regulated and its expression was parallel with GH and GHR1 expression in liver of fish fed Diet 3. The expression of GH and GHR1 genes in spleen down regulated in all fish fed Diet 2, Diet 3 and Diet 4. On contrary, the expression level of IGF-I in spleen of fish received either Diet 3 or Diet 4 was slightly up regulated, but IGF-I mRNA level was down regulated in fish fed Diet 2 than other treatments. The expression level of GH, IGF-I and GHR1 genes were down regulated in intestine of fish fed synbiotic than other control diet.