Preliminary use of Polygonum minus Linn. leaf extract on growth performance, feed utilization, and some hematological indices of Anabas testudineus (Bloch, 1792)

The main objectives of the present study were to improve the growth performance, survival rate, and hematological indices of fingerling Anabas testudineus, by using Polygonum minus plant leaf extract, sprayed at four different levels (0 as the control group, 50, 70, and 100 ml/kg fish feed), for 60 days. The growth indices and survival rate were investigated at 15-day intervals, while hematological indices were evaluated at the end of experiment (60 days). The results showed that the weight gain (WG), average daily growth rate (ADG), specific growth rate (SGR), feed efficiency (FE), and protein efficiency ratio (PER) values were significantly different, and that the highest value in the group was found in fish fed 70 ml/kg feed. Meanwhile, feed conversion rate (FCR) was shown to have the lowest value in the group that was fed 70 ml/kg feed. In addition, the survival rate was shown to be higher in all groups except for the control group: a significant difference (p < 0.05). Also, the dietary supplementation, with P. minus extract, caused a significant difference in total white blood cell count (WBC) among the treatments, the highest cell value of WBC was found in the group of fish fed 70 and 100 ml/kg feed. Although the red blood cells (RCB) and hematocrit (Htc) concentrations were not significantly different (p > 0.05), there was a trend towards higher concentrations. Overall, our results indicated that P. minus leaf extract supplementation could improve growth performance, especially with regard to feed utilization, and the survival rate was very important for the fingerling nursing step; moreover, the WBC could be improved by using herbal extracts.