Phytochemical screening and masculinization of nile tilapia (oreochromis niloticus linnaeus) using the needle and root crude extracts of benguet pine (pinus kesiya royle ex gordon)
This study evaluated the effect of Benguet pine (Pinus kesiya) needle and root
extracts in the masculinization of Nile tilapia (Oreochromis niloticus) fry. The crude extracts
of Benguet pine were phytochemically screened and found positive for steroid for root extracts
while chlorophyll and xantene were present in needle extracts. Toxicity assay was conducted to
evaluate the median lethal concentration (LC50) after 96 hours. Probit analysis revealed LC50
was 150 ppm and 960 ppm for Benguet pine needles and roots, respectively. Temperature,
dissolved oxygen (DO) and pH did not differ statistically in all treatments (P>0.05). For the
sex-reversal, treatments were as follows; I-fry booster only, II- diet with 50 mg/kg
methyltestosterone, III- diet with 100 ppm Benguet pine needle extract and IV-diet with 500
ppm Benguet pine root extracts. Results revealed no significant difference was observed in the
survival and growth rate of different treatments (P>0.05). No sex inversion was observed in the
diet with 100 ppm Benguet pine needle crude extract and diet with 500 ppm Benguet pine root
crude extracts 62.27±7.02% and 61.51±5.88%, respectively. Percent males were significantly
different at 50 mg/kg methyltestosterone compared to other treatments. No intersex gonads
were observed in all treatments. Temperature, dissolved oxygen (DO) and pH did not differ
statistically in all treatments (P>0.05) after 28-day sex-reversal in outdoor tanks.