A novel method, BBD-SSPD is proposed by the combination of Box-Behnken Design (BBD) and Split-Split Plot Design (SSPD) which would ensure minimum number of experimental runs, leading to economical utilization in multi- factorial experiments. The brine shrimp Artemia was tested to study the combined effects of photoperiod, temperature and salinity, each with three levels, on the hatching percentage and hatching time of their cysts. The BBD was employed to select 13 treatment combinations out of the 27 possible combinations that were grouped in an SSPD arrangement. Multiple responses were optimized simultaneously using Derringer’s desirability function. Photoperiod and temperature as well as temperature-salinity interaction were found to significantly affect the hatching percentage of Artemia, while the hatching time was significantly influenced by photoperiod and temperature, and their interaction. The optimum conditions were 23 h photoperiod, 29 °C temperature and 28 ppt salinity resulting in 96.8% hatching in 18.94 h. In order to verify the results obtained from BBD-SSPD experiment, the experiment was repeated preserving the same set up. Results of verification experiment were found to be similar to experiment originally conducted. It is expected that this method would be suitable to optimize the hatching process of animal eggs.

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Grey mullet is a potential species for diversification of aquaculture due to fast growth, omnivorous feeding habits and the high market value of the fish as well as its value-added products such as salt-cured and dried eggs called 'bottarga' (Vinatea et al., 2018;Whitfield et al., 2012). The euryhaline and eurythermal characteristic of grey mullet helps in better adaptation to captive condition and makes it a suitable candidate for brackish water aquaculture.The nutritional attributes such as ω-3 and ω-6 fatty acids and essential amino acid contents make grey mullet as an appropriate

An experimental trial was conducted for 90 days to evaluate the effect of different carbon sources viz. yam and potato on growth performance of milkfish (Chanos chanos) in biofloc‐based system. Milkfish fry (average body weight of 0.66 ± 0.01 g) was stocked in biofloc treatments, yam‐based biofloc (BFY) and potato‐based biofloc (BFP), and clear water (CW) as control in triplicates. Milkfish reared in biofloc‐based units obtained significantly better (p < 0.05) performance in terms of growth, digestive enzyme activity and survival when compared to clear water control. Among the biofloc‐based treatments, the highest average body weight (11.62 ± 0.24 g), specific growth rate (3.21 ± 0.01% day−1), percentage weight gain (1688.10 ± 19.05) and survival (90.83 ± 2.01%) were found in BFY group. Similarly, the essential amino acid and non‐essential amino acid contents of biofloc and experimental fish were higher in BFY as compared to BFP. Additionally, the highest level of EPA (eicosapentaenoic acid), DHA (docosahexaenoic acid) and total n‐6 and n‐3 PUFA were found higher in BFY. Bacterial composition analysis showed that BFY treatment groups had a more diverse bacterial community than those with BFP treatment groups. This study demonstrated that biofloc‐based culture system is suitable for rearing of C. chanos fry and the most preferable type of carbon source is found to be Yam.

Aim: To assess the impact of different carbon sources on growth performance of grey mullet, Mugil cephalus fry in biofloc based culture system during nursery rearing phase. Methodology: The experimental trial was carried out for 60 days using three carbon sources, cassava, jaggery and barley in triplicate following a Completely Randomized Design. The carbon nitrogen ratio (C:N) in the systems were maintained at 15:1. Grey mullet fry (0.91g) were stocked @ of 1 fry 10 l-1 and were fed with pelleted feed (35% crude protein) @ 4% of fish body weight thrice daily. Results: Significantly higher (P<0.05) growth performance, in terms of Specfic Growth Rate (3.78 % day-1) with lower Feed Conversion Ratio (1.35) were found in barley based biofloc group. Similarly, enhanced digestive enzyme activity in terms of amylase (8.78 Unit mg protein-1 min-1), lipase (2.77 Unit mg protein-1 min-1) and protease (4.22 Unit mg protein-1 min-1) were found in barley based biofloc group. Non- specific immune parameters such as lysozyme, respiratory burst activity and myeloperoxidase activity were significantly higher in barley based treatment group followed by jaggery and cassava based treatment groups. Likewise, stress indicators in serum and antioxidant status in liver were found to be lower in barley based treatment compared to cassava and jaggery based treatment groups. Interpretation: Rearing of Mugil cephalus in biofloc culture system is practicable; however, the carbon source required for biofloc production could be barley, compared to cassava and jaggery, in order to achieve maximum growth and to reduce the stress.