Morphometrics, fillet yield and fillet composition in Nile tilapia, Oreochromis niloticus, strains thai chitralada, Brazil local and their hybrid

Abstract

Morphometrics, fillet yield and fillet composition differences were researched in Nile tilapia, Oreochromis niloticus, strain thai-chitralada (Tai), Brazil (Local) Northern Paraná and their hybrid (Hbr, male Thailand x Brazilians female ). The experiment was designed entirely randomly with three treatments (strains) and three repetitions per treatment in hapa nets in ponds. The initial weights were 0.39 ± 0.20, 0.45 ± 0.22 and 0.41 ± 0.15 g for the strains Tai, Bras and Hbr, respectively. At the end of the experiment, the weights were 650.67, 534.25 and 360.00 g for the same previous sequence, with statistically significant differences between groups (P < 0.05). Four morphometric proportions were established to characterise each group. For the ratio (head height)/(head length), the Tai strain was largest (P < 0.05) as compared to the two other strains. The other morphometric proportions were not different (P > 0.05). The strain Hbr produced (P < 0.05) greater fillet yield (39.05%) when compared to Local (38.00 %) and Tai (36.51 %), the latter two were not different from each other (P > 0.05). Considering fillet composition, Local strain had the least crude lipid content of (1.88 %), as compared to Hbr (2.44 %) and Tai (2.96 %) which were significantly different (P<0.05). Crude protein, ash and moisture of the fillets were not different (P> 0.05).