Effect of feeding frequency on growth, survival and feed utilization in mrigal, Cirrhinus mrigala, and rohu, Labeo rohita, during nursery rearing

The effect of feeding frequency on growth, survival and feed utilization in mrigal, Cirrhinus mrigala, and rohu, Labeo rohita, during raising fry were studied in 50-m2 cement nurseries provided with 10 cm soil base. Feeding frequency of one, two and three times daily as three treatments were evaluated against a control without feeding in triplicate tanks in two separate trials of 15 days each. Hatchery produced spawn were stocked at the density of 10 million/ha. With the survival levels lying in the narrow ranges of 44.01–46.71% in mrigal and 53.03–56.65% in rohu, no significant differences (P > 0.05) were recorded between the treatments. Similarly, the growth in terms of length and the feed conversion ratios did not differ significantly (P > 0.05) among treatments and were in the ranges of 34.6–34.9 mm and 27.5–28.9 mm, and 0.80–0.81 and 1.33–1.47 in mrigal and rohu, respectively. The study suggests that feeding frequency of one time daily is sufficient for nursery raising of carp fry in field condition in presence of natural food in the form of plankton.