Growth Performance and Protein-Nutritional Status of Wistar Rats Given Aqueous Justicia carnea Leaf Extract for 14 Days

Background: The aqueous leaf extract of Justicia carnea is consumed in Nigeria as a nutritive blood tonic, but its growth and protein-nutritional effects in growing animals remain insufficiently characterised. Aim: To evaluate body-weight gain, growth rate, serum total protein and albumin in young male Wistar rats given the aqueous leaf extract for 14 days. Methods: Twenty-four rats received distilled water (control, n = 4) or extract at 200, 400, 600 or 800 mg/kg (n = 5 per group) by daily oral gavage. Body weight was recorded at three-time points. Serum total protein and albumin were determined in 14 rats after treatment. Analyses included one-way ANOVA and ANCOVA adjusting for initial body weight. Results: All rats survived. Final body weight did not differ between groups (144.0–165.0 g; p = 0.375). Unadjusted percentage weight gain was highest in controls (61.8 ± 26.2%) and showed a negative correlation with dose (ρ = −0.46; p = 0.029). Rats receiving 800 mg/kg had higher initial weight than controls (126.0 ± 18.2 versus 102.5 ± 5.0 g; p = 0.013). Initial weight was negatively correlated with proportional gain (r = −0.61; p = 0.002). After adjustment, percentage weight gain did not differ significantly among groups (p = 0.338). Serum total protein (p = 0.499) and albumin (p = 0.836) were also comparable. Conclusion: These findings showed no statistically significant difference in baseline-adjusted growth or measured serum protein indices over 14 days, despite the unadjusted association between dose and weight gain.