Effects of different food on physical property changes of ponds and the growth of eels.

The objectives of this research were to study the effect of different foods on the physical characteristics of ponds and growth rate of eels by simulating farming to mimic nature in cement ponds. The pH of the ponds was adjusted to be in the range of pH 6-9 and the experiment was conducted by farming eels in 9 cement ponds. Four eels were released into each pond (3 females: 1 male). CRD (Completely Randomized Design) was used to plan the experiment which was divided into three groups in which three kinds of food were supplied; fresh golden apple snails, prawn food and catfish food. Feeding was every two days (feeding time was 17.00 to 18.00) and the eels were fed for 6 months (February-July 2019). The research found that the temperature outside and inside the cement pond during each month changed according to the air environment.The storage temperature outside the pond and the temperature inside the pond from February to July was in the range of 29-34 °C. The temperature each month varied with the outside temperature. The water pH of the pond was 7.29 to 7.66 and the BOD values were within standards between 5.30 and 6.70. The average soil moisture content before and after culture in the ponds fed with golden apple snails, prawn food and catfish food were 11.35%, 11.90 % and 11.28 %, respectively, and 18.57%, 18.48 % and 17.93 %, respectively. The soil density and the soil pH before and after culture was in the range of 1.79-1.99 mg/m3 and 1.45-1.47, mg/m³ and 6.6-6.8 and 7.4-7.7, respectively. The soil texture before and after culture was clay. It was also found that the survival rate of eels was 60-70 %. The average weight of eels before and after feeding with fresh apple snails, prawn food and catfish food was 222.50, 210.00, 230.00 g, respectively, and 416.25, 322.75 and 307.75 g, respectively. Feeding the eels with golden apple snails brought about the best growth. The weights of eels cultured in cement ponds with different feeding regimes were significantly different, (p<0.05). [ABSTRACT FROM AUTHOR]