Growth performance, length-weight relationship and condition factor of backcross and reciprocal hybrid catfish reared in net cages

Abstract

This study was designed to investigate the growth performance, Length-Weight Relationship (LWR) and condition factor (k-value) of reciprocal backcross hybrid catfish (RCBC), Pangasianodon gigas (female)xF1 hybrid (male) catfish and backcross hybrid catfish (BC), P. gigas (male)xF1 hybrid (female) catfish. Moreover, this study also compared the above mentioned species of catfish were compared with P. gigas and F1 hybrid P. gigas (male)×P. hypophthalmus (female) catfish. The fish were reared in net cages for 5 months (October, 2013-March, 2014). The results showed that, Weight Gain (WG) and average daily weight gain (ADG) were the highest among the P. gigas (34.45 and 0.20, respectively). The Length Gain (LG), average daily length gain (ADL) and Specific Growth Rate (SGR) were highest among the RCBC (10.66, 0.062 and 2.34, respectively). While the survival rate (55%) was highest among the BC. The Feed Conversion Rate (FCR) showed high numbers in all fish except the hybrids. On the other hand, the hybrid species showed lower results in all growth indices except for the survival rate but which had as high a tendency as the RCBC. The LWR revealed “b” values for the P. gigas, RCBC, BC and F1 hybrid that were 2.94, 3.12, 2.67 and 2.03 indicating that P. gigas and RCBC displayed isometric growth while others showed allometric growth. The k-values for each month showed significant differences (p<0.05) but the k-values averaged over 5 months were not significant (p>0.05). The results from this study revealed that the RCBC is suitable for the aquaculture industry and moreover, the information collected in this study on LWR and the condition factor of each fish will be useful for fishery management.