Efeito do peso de abate nos rendimentos do processamento da piracanjuba (Brycon orbignyanus, Valenciennes, 1849)

Abstract

The objective of this study was to evaluate the effect of body weight on processing yields of a teleost fish piracanjuba (Brycon orbignyanus, Valenciennes, 1849). Firstly, fingerlings were reared in ponds in the Fish Culture of the Animal Sciences Department, Federal University of Lavras, M.G. – Brazil, for 18 months. Then, 121 fishes were insensibilized, slaughtered, weighed and dissected, in order to determine the percentages of head (%CAB), fins (%NAD), visceras (%VIS), skin with scales (%PE), and fillet residues (%RF), and the carcass yield (RCAR) and fillet without skin yield (RFSP), in relation to body weight. For analyses of variances, data were distributed over four weight classes (CP1 = 515 to 629g; CP2 = 630 to 744g; CP3 = 745 to 859g; and CP4 = 860 to 975g) and the regression equations were estimated in function of mean weight of each class. There was no effect (P>0,05) of weight class on RCAR, %NAD and %PE. However, a linear effect of body weight on %CAB (P<0,01), %RF (P<0,01) and RFSP (P<0,09) and a quadratic effect on %VIS (P<0,05) were observed. The %CAB and %RF decreased while RFSP and %VIS increased, with the increase of body weight. Based on these results, it can be concluded that heavier piracanjubas provide larger RFSP, smaller %CAB and smaller %RF. The smaller %CAB on heavier fish did not increase RCAR, as expected probably because of the increase on %VIS.