The inclusion of biological silage from chicken intestines and blood in the feed for Nilotic tilapia Oreochromis niloticus, substituting 80% of the protein content of fishmeal, was evaluated. The silages were made with 70% waste, 15% energy source (14% molasses and 1% sugar) and 15% yogurt (lactic acid bacteria). The pH and acidity were determined for 180 days, and the chemical analysis was done using standard methods. The base diet was formulated with the minimum cost equation, and considering the nutritional requirements for tilapia, inclusion levels and cost of inputs. A control diet and two with silages were used. The fingerlings (n=270) with an initial weight of 5.17 ± 0.18 g were randomly distributed in nine aquariums (3 per diet). The fish were fed three times a day and evaluated monthly. A significant difference (p<0.05) was found in the final weight and biomass averages betw...

Albino fish have greater economic value than fish that have coloration both at the ornamental level and at the consumption level for their meat. Th e slc45a2 gene is associated with the induction of an albinism phenotype initially reported in Zebrafish (Danio rerio Hamilton, 1822) and Medaka fish (Oryzias latipes Temminck & Schlegel, 1846). With the information registered in the Genbank of the slc45a2 gene of the Tilapia fish (Oerochromis niloticus Linnaeus, 1758) and the Gamitana (Colossoma macropomum Bleeker, 1869), specific primers were designed in silico to identify this gene in these two freshwater species. Both sets of primers were used fi rst on these two species (Tilapia and Gamitana). And then tested in the fi sh Paco (Piaractus brachypomus Cuvier, 1818) and Oscar (Astronotus ocellatus Agassiz, 1831) whose slc45a2 gene sequences are currently unknown. With the set of primers...