niloticus THE INFLUENCE OF SYNBIOTIC ON GROWTH AND EXPRESSION OF GH , GHR 1 AND IGF-I GENES IN Oreochromis niloticus L FINGERLINGS

Tilapia is a worldwide fish of great commercial importance and it is recognized as one of the most important aquaculture species of the 21st century. The world’s total tilapia production in 2010 was 3.49 million tons [1]. Unfortunately, intensive aqua-farming is accompanied by several problems where the disease infection is a limiting factor for the production through the negative impact on growth. One of the main challenges to achieve productive, feasible and sustainable aquaculture is to develop alternative preventive practices that may help to maintain high animal welfare standards as well as healthy environment, resulting in a better production and higher profits. A novel approach to achieve the above mentioned goals is an application of probiotics and prebiotics in the fish farming industry [2-4]. In a practical sense, probiotics are defined as live microorganisms that are used as dietary supplementations in aquaculture and could enhance the growth and health of the host [5,6]. Gibson and Robefroid [7] defined prebiotics as ‘nondigestible food ingredients that beneficially affects the host by selectively stimulating growth and/or activity of one or a limited number of bacteria in the colon’ through the combination of probiotics and prebiotics in socalled synbiotics. Also they reported that the use of the synbiotics concept may give the benefit of both preand probiotics on fish growth. The synergistic effect may improve the survival of the probiotic organism, where the simultaneous presence of probiotic and prebiotic reward the host in a proper manner [8]. Few data are available regarding the application of synbiotics in aquaculture [911]. The research on the effects of synbiotic on levels of growth hormone (GH), insulin like growth factor I (IGF-I) and their gene expression in fish is very limited. In fish, growth is under the control of GH secretion from the pituitary, regulating somatic growth, organ and tissue growth and metabolic processes [12]. Most of these biological functions are mediated by plasma IGF-I, released from the liver in response to circulating GH [13]. Indeed, the hypothesis that the GH/IGF-I axis could be used as a marker of growth performance and nutritional status in aquaculture has already been suggested [14]. Thus, there is obviously a need to excess our knowledge of the effective preparation and safety valuation of synbiotics. Hence, this trial aimed to assess the effect of synbiotic with Citation: Hassaan M.S.M., et al. (2015) The Influence of Synbiotic on Growth and Expression of GH, GHR1 and IGF-I Genes in Oreochromis niloticus L Fingerlings. Journal of Fisheries and Aquaculture, ISSN: 0976-9927 & E-ISSN: 0976-9935, Volume 6, Issue 1, pp.-176-182.