Table 3.
The effect of partial replacement of fish meal with whey protein concentrates on immune status, blood levels of growth hormone and nitric oxide, and kidney and liver function tests of Nile tilapia fingerlings at the end of the experiment.
| Parameters | WPC0 | WPC13.8 | WPC27.7 | WPC41.6 | WPC55.5 | Regression Analysis * | |
|---|---|---|---|---|---|---|---|
| Linear | Quadratic | ||||||
| Immunological tests | |||||||
| IgM (µg/mL) | 237.33 ±2.02 | 251.00 ±6.80 | 256.66 ±10.03 | 255.66 ±12.12 | 260.33 ±12.12 | 0.120 | 0.501 |
| Lysozymes (µg/mL) | 14.89 ±0.29 | 18.48 ± 0.32 | 21.06 ± 3.32 | 22.22 ± 1.68 | 26.03 ±2.85 | 0.003 | 0.905 |
| Complement 3 (µg/mL) | 106.66 ±2.40 | 111.66 ±1.76 | 114.33 ±2.33 | 121.00 ±3.21 | 127.33 ±3.28 | 0.00 | 0.519 |
| Phagocytic % | 35.33 ±2.40 | 38.33 ± 2.02 | 52.66 ± 0.66 | 45.66 ± 1.20 | 42.66 ±1.76 | 0.002 | 0.00 |
| Phagocytic index | 1.25 ± 0.08 | 1.53 ± 0.14 | 2.98 ± 0.10 | 2.29 ± 0.10 | 1.84 ± 0.07 | 0.00 | 0.00 |
| Growth hormone (ng/mL) | 1.59 ± 0.05 | 2.04 ± 0.14 | 2.55 ± 0.28 | 3.03 ± 0.03 | 4.44 ± 0.29 | 0.00 | 0.02 |
| NO (µmol/L) | 55.34 ±2.24 | 61.34 ± 1.62 | 60.19 ± 2.86 | 65.94 ± 3.59 | 69.44 ±6.99 | 0.02 | 0.90 |
| Liver function tests | |||||||
| ALT (U/L) | 12.03 ±0.11 | 11.03 ± 0.08 | 11.91 ± 0.02 | 12.80 ± 0.02 | 13.12 ±0.04 | 0.14 | 0.00 |
| AST (U/L) | 9.12 ± 0.04 | 7.90 ± 0.03 | 9.30 ± 0.02 | 9.73 ± 0.04 | 13.85 ±0.02 | 0.00 | 0.00 |
| Kidney function tests | |||||||
| Urea (mg/dL) | 7.14 ± 0.06 | 6.92 ± 0.018 | 5.92 ± 0.03 | 13.86 ± 1.55 | 3.38 ± 0.06 | 0.00 | 0.001 |
| Creatinine (mg/dL) | 0.53 ±0.002 | 0.52 ± 0.002 | 0.53 ± 0.002 | 0.62 ± 0.004 | 0.56 ±0.001 | 0.002 | 0.07 |
* The regressions were considered significant when p ≤ 0.05.