Effects of feeding frequency using automatic fish feeder machine on nursing broad head catfish larvae in the concrete tank

Abstract

The objective of the study was to investigate the effects of growth rate, survival rate and water quality of broad head catfish larvae with the initial weight of 2.70 ± 0.07 g. The experiment was designed by using factorial 3x2 in completely randomized design was employed with two factors divided into three treatments regarding to the different power supply of feeders (solar energy machine, electricity and farm labor). The frequency feeding time were considered by twice daily (8 am and 4 pm) and 3 times daily (8 am, 4 pm and 12 pm) for 90 days. The results revealed that growth and survival rates of catfish obtained from different feeding methods were not significantly different (P > 0.05), with the growth rates ranged from 0.54 ± 0.03 to 0.61 ± 0.22 g.d-1, survival rate were 89.53 ± 3.11 - 90.86 ± 4.73% and feed conversion ratio were 2.24 ± 0.78 - 2.46 ± 0.30. Water quality were measured twice daily at 6 am and 6 pm with, respectively, dissolved oxygen ranged from 5.05 – 5.99 and 5.45- 6.49 mg.L-1, pH value of 5.34 – 7.34 and 6.12 - 7.94, temperature of 26.43 oC – 29.12 oC and 28.76 oC – 29.39 oC, ammonia ranged from 0.003 - 0.024 mg.L-1, nitrite of 0.001-0.004 mg.L-1 and nitrate of 0.001-0.006 mg.L-1. These indicated the daily average water quality of the three groups were not significantly different (P > 0.05).Therefore, automatic feeders (solar energy machine) can be used to nursery broad head catfish larvae in concrete tank. Influencing consumption behavior at the early stage of catfish affects to total yield and growth rate could be increased but does not affect water quality.