Provision levels of Nile tilapia post-larvae to pacamã (<i>Lophiosilurus alexandri</i>) fingerlings

Abstract

The present work aimed to study the level of provision of the Nile tilapia (Oreochromis niloticus Linnaeus, 1758) post-larvae as live food for pacamã (Lophiosilurus alexandri Steindachner, 1876) fingerlings. Twelve pacamã fingerlings (397 ± 39 mg and 30 days old) from a single spawning, were distributed in completely randomized design with three treatments and four replications for a period of 29 days. The treatments were the supply of biomass levels of Nile tilapia post-larvae, in the ratio of 30; 60; and 95% of the live weight of the pacamã fingerlings. The fingerlings were weighed and measured weekly, for the adequacy live food supply. Daily (16:00h) post-larvae from live food were counted and replaced. At the end of the experiment all fish were used to evaluate the variables of performance. There was a linear decrease (P < 0.01) in final weight, final length and weight of the carcass with and without head of fingerlings of pacamã when the increased supply of biomass of live food. There was a linear increase (P < 0.01) in feed  conversion with the increase in the supply of live food. The percentage of carcasses with and without head, were not affected by treatments (P > 0.05). Post-larvae of Nile tilapia are suitable for feeding of pacamã fingerlings and it is recommended to provide a level of 30% of its live weight.