الفهرس 
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Abstract
Chapter 1
Modulatory effects of various carbon sources on growth indices, digestive enzymes activity and expression of growth-related genes in Whiteleg shrimp, Litopenaeus vannamei reared under an outdoor zero-exchange system
Abstract:
In this study, we investigate the effect of the biofloc (BF) system using various carbon sources including sugarcane bagasse (SCB), rice bran (RB) and rice straw (RS) on growth parameters, hepatopancreatic digestive enzymes and the expression of growth-related genes of white-leg shrimp, Litopenaeus vannamei. Single-nucleotide polymorphisms (SNPs) in the hemocyanin gene in small-and large-sized Litopenaeus vannamei for 3 months reared in outdoor concrete ponds were also screened. The results showed that the growth and survival of shrimp in the RB and SCB groups were improved (p ≤ 0.05) and the same trend was observed for the digestive enzyme activities. The expression of different growth-related genes including growth hormone, insulin-like growth factor-I and II, myosin and paramyosin was significantly increased in all biofloc groups reaching the highest levels in the RB group. The SNPs recorded in the hemocyanin gene between the small-and large-sized L. vannamei revealed an insertion of Adenine at position 554 and a substitution at 1114 in large-sized RS shrimp. So far, the RB group was attained the best growth, digestive enzyme activity and expression of growth-related genes between different carbon sources. Furthermore, the hemocyanin gene can be used as a marker for the selection of large-sized shrimp.
Chapter2
Carbon sources improve water quality, microbial community, immune-related and antioxidant genes expression and survival of challenged Litopenaeus vannamei Postlarvae in biofloc system
Abstract:
The influence of different processed agriculture wastes as carbon sources including sugarcane bagasse (SCB), rice bran (RB) and rice straw (RS) on water quality, microbial community, and expression of immune-related and antioxidant genes in both hepatic and muscle tissues was evaluated. Furthermore, the cumulative mortality rates of Litopenaeus vannamei when challenged with Vibrio and Shewanella algae were estimated. The experiment lasted for 3 months in outdoor culture ponds, and the results indicated that the water quality parameters improved with different biofloc (BF) treatments. The total heterotrophic bacteria were increased in the BF treatments until the end of the experiment when compared to the control group. Regarding the hepatic and muscular expression of immune-related genes such as beta-glucan-binding protein, lipopolysaccharides/b-glucan-binding protein, prophenoloxidase, lysozyme, crustin, transglutaminase, hemocyanin and antioxidant genes including glutathione peroxidase and superoxide dismutase, the SCB treatment was higher in all genes expression among different BF treatments and control. Moreover, the SCB treatment also had the best survival rate compared with RB, RS and control treatments when challenged with both Vibrio and Shewanella algae. In general, these results suggested that the SCB is an ideal carbon-rich food source, boosts the immune system and promotes disease resistance of L. vannamei.