Effects of Different Salinity Levels on Water Quality, Growth Performance and Body Composition of Pacific White Shrimp (Litopenaeus vannamei Boone, 1931) Cultured in a Zero Water Exchange Heterotrophic System

Abstract

<jats:title>Abstract</jats:title><jats:p>The present study was aimed to evaluate the effects of different levels of salinity on water quality, growth performance, survival rate and body composition of Pacific white shrimp in a heterotrophic/biofloc technology (BFT). Shrimp post-larvae with an average weight of 74.46 mg were cultured in 300 L fiberglass tanks containing 130 L water at a density of 1 post-larva/L. Three treatments including different levels of salinity of 8, 21 and 32 ppt with three replicates were considered. The highest levels of body weight, growth rate, specific growth rate, increase in body length and survival rate were observed at high salinity level (32 ppt). The highest feed conversion ratio (FCR) and the lowest level of feed efficiency were obtained in shrimps cultured at lowest salinity level (P&lt;0.05). Biochemical analysis of shrimp body composition showed an increase in protein, lipid and ash content as the salinity elevated (P&lt;0.05). The zero-water exchange system used in this study had no significant effects on water quality parameters. The results of the present study concluded that high salinity level (32 ppt) improves the growth and survival of the biofloc supplemented Pacific white shrimp in a BFT system.</jats:p>

The Effect of Adding Molasses in Different Times on Performance of Nile Tilapia (Oreochromis niloticus) Raised in a Low-Salinity Biofloc System

“…Studies by various researchers have reported that the biofloc system improves the growth performance of cultured aquatics (Avnimelech and Kochba, 2009;Luo et al, 2014, Wang et al, 2015Mirzakhani et al, 2019;Khanjani et al, 2020b). The increase in growth performance in BFT24 treatment is possibly because of maintaining optimal water quality and continuous and fresh production of biofloc (Ekasari et al, 2010;Toledo et al, 2016).…”

“…The lipid content of bioflocs is usually at the low level, but the presence of essential fatty acids has significantly increased their nutritional value (Ju et al, 2008;Khatoon et al, 2016). The type of carbon source (Khanjani et al, 2017), C: N ratio (Minabi et al, 2020), water salinity (Ekasari et al, 2010;Khanjani et al, 2020b), feeding level (Khanjani et al, 2016), the source of light and its intensity (Coyle et al, 2011), pH (Martins et al, 2019) and the type of microbial community (Ahmad et al, 2017) are considered as parameters affecting the biochemical composition of bioflocs.…”

“…The biofloc in the production system affects water quality (García-Ríos et al, 2019;Ren et al, 2019), growth performance (Khanjani et al, 2020b;Durigon et al, 2020), digestive enzyme activity (Najdegerami et al, 2016;Xu and Pan, 2012), immunity (Long et al, 2015;Menaga et al, 2019), antioxidant status (Bakhshi et al, 2018;Liu et al, 2018) and body composition of the cultured species (Mirzakhani et al, 2019;Khanjani et al, 2020a).…”

Effects of Diets Containing Beta-Glucan on Survival, Growth Performance, Hematological, Immunity and Biochemical Parameters of Rainbow Trout (Oncorhynchus Mykiss) Fingerlings

“…Success in aquaculture is achieved by improving genetics, nutrition, immunity and disease control in farmed species. Parameters such as speci c growth rate, feed conversion ratio and survival rate play a key role in evaluating an aquaculture system (Ghaedi et al 2015, Khanjani et al 2020b). The use of immunostimulants is considered as an effective tool to overcome diseases and strengthen the immune system of farmed organisms (Meena et al, 2013).…”

Supplemental carbon sources applied in biofloc technology aquaculture systems: types, effects and future research

“…A C/N ratio in the substrate ranging from 10 to 20 is considered optimal for heterotrophic bacteria to assimilate NH þ 4 -N (Goldman et al 1987;Avnimelech 1999;Avnimelech 2006;Avnimelech 2007;Crab et al 2012). Recently, supplying molasses (C/N of 15) to a shrimp based biofloc system resulted in an increase in the populations of heterotrophic bacteria, which caused a corresponding decline in the concentrations of ammonia and nitrite, respectively (Khanjani et al 2020c). Theoretically, 6.07 parts of organic carbon are required for heterotrophic bacteria to convert each part of NH þ 4 -N to biomass (NH Ebeling et al 2006).…”