Figure 1.
Zootechnical variables of Cryphiops caementarius reared using biofloc technology (BFT) with different carbon sources during the 142 days of the experiment
| Parameters | Treatments | ||
|---|---|---|---|
| molasses | chancaca | control | |
| Initial mean weight (g) | 24.58±3.15 | 24.58±3.15 | 24.58±3.15 |
| Final mean weight (g) | 25.26±6.80 b | 29.80±4.36 a | 29.68±5.26 a |
| Specific growth rate (% day−1) | 0.74±0.12 b | 0.89±0.15 a | 0.89±0.21 a |
| Survival (%) | 33.33±6.12 | 23.33±5.77 | 23.33±5.77 |
Chemical composition of bioflocs generated with two carbon sources
| Carbon source | Protein (%) | Lipids (%) | Fiber (%) | Ash (%) | Humidity (%) | NFE (%) | Gross energy (kJ·g−1) |
|---|---|---|---|---|---|---|---|
| Chancaca | 31.20±1.71 | 4.53±1.86 | 11.17±2.19 a | 38.97±6.81 | 92.53±1.64 | 14.13±9.43 b | 1133.41±125.01 |
| Molasses | 29.57±2.32 | 4.87±2.04 | 8.70±4.56 b | 38.23±3.12 | 91.43±2.24 | 18.63±9.96 a | 1185.95±93.02 |
Total microorganism abundances in biofloc systems using different carbon sources after 142 days of rearing Cryphiops caementarius
| Microorganism composition | Molasses | Chancaca | Control |
|---|---|---|---|
| Total bacteria (CFU×105 mL−1) | 3.51±1.38 a | 2.37±0.65 b | 1.66±0.39 c |
| Vibrio spp. (CFU×105 L−1) | 0.00±0.00 | 0.00±0.00 | 0.00±0.00 |
| Chlorophyceae (cell mL−1) | 430.33±88.79 b | 581.33±71.06 a | 64.01±18.52 c |
| Bacillariophyceae (cell mL−1) | 119.11±15.37 b | 156.66±15.61 a | 5.19±3.36 c |
| Cyanophyceae (cell mL−1) | 92.33±28.38 b | 125.66±24.99 a | 0.00±0.00 b |
| Rotifer (ind. L−1) | 58.67±23.45 a | 41.00±19.05 b | 4.00±3,61 c |
| Cladocera (ind. L−1) | 42.12±12.74 a | 30.33±17.31 b | 0.00±0.00 b |
| Annelids (ind. L−1) | 3.30±1.43 a | 3.33±1.52 a | 0.00±0.00 b |
| Nematode (ind. L−1) | 2.00±1.21 b | 10.33±1.41 a | 0.00±0.00 c |
| Copepod (ind. L−1) | 1.45±1.42 a | 2.00±1.73 a | 0.00±0.00 b |
| Ciliates (ind. L−1) | 134.67±61.59 a | 46.00±26.52 b | 15.00±7.93 c |
Water quality parameters
| Water quality parameters | Molasses | Chancaca | Control |
|---|---|---|---|
| Temperature (°C) am | 22.5±0.89 | 22.7±0.91 | 22.7±0.91 |
| Temperature (°C) pm | 23.7±1.11 | 24.0±0.90 | 24.1±1.09 |
| Dissolved oxygen (mg L−1) am | 8.08±0.25 | 8.08±0.30 | 8.08±0.26 |
| Dissolved oxygen (mg L−1) pm | 7.83±0.22 | 7.80±0.35 | 7.87±0.21 |
| pH | 8.69±0.20 | 8.80±0.12 | 8.54±0.21 |
| TAN (NH3-N mg L−1) | 0.27±0.15 b | 0.62±0.19 a | 0.28±0.65 b |
| Nitrite-N (NO2 mg L−1) | 0.33±0.22 c | 0.70±0.15 b | 0.94±0.71 a |
| Nitrate-N (NO3 mg L−1) | 62.84±10.56 a | 26.39±11.59 b | 50.73±33.89 a |
| Phosphorus (PO4−3 mg L−1) | 4.34±2.86 a | 1.48±1.22 b | 3.98±3.26 a |
| Total hardness (mg CaCO3 L−1) | 1068.67±244.68 a | 936.67±130.33 a | 740.33±159.67 b |
| Total alkalinity (mg CaCO3 L−1) | 255.06±38.63 a | 205.33±39.91 b | 156.33±43.01 c |
| FV (mL L−1) | 26.75±12.51 a | 15.27±8.12 b | 1.87±2.16 c |
| TSS (mg L−1) | 287.15±37.85 a | 214.20±39.97 b | 102.14±15.07 c |
Taxonomic composition of plankton communities in biofloc systems with different carbon sources following culturing after 142 days of rearing of Cryphiops caementarius
| Microorganism composition | Molasses | Chancaca | Control |
|---|---|---|---|
| Bacillariophycea | |||
| Synedra sp. | + | + | + |
| Navicula sp. | + | + | + |
| Nitzchia sp. | + | + | + |
| Chlorophyceae | |||
| Palmella sp. | + | + | + |
| Chlorella sp. | + | + | + |
| Scenesdesmus sp. | + | + | + |
| Cyanophyceae | |||
| morphotype 1 | + | + | + |
| Rotifer | |||
| Philodina sp. | + | + | + |
| Lecane sp. | + | + | + |
| Cephalodella sp. | + | + | + |
| Cladocera | |||
| Chydorus sp. | + | + | − |
| Nematode | |||
| Monhytera sp. | + | + | − |
| Annelid | |||
| Aelosoma sp. | − | + | − |
| Copepod | − | + | |
| Cyclops sp. | + | + | − |
| Amoeba | |||
| Amoeba sp. | + | − | − |
| Ciliates | |||
| Paramecio sp. | + | + | + |
| Coleps sp. | + | + | + |
| Vorticella sp. | + | + | + |
| Halteria sp. | + | + | + |