&lt;b&gt;Direct and indirect effects of measures and reasons morphometric on the body yield of Nile tilapia, &lt;i&gt;Oreochromis niloticus&lt;/i&gt;&lt;/b&gt; - doi: 10.4025/actascianimsci.v35i4.19807

Carlos Cicinato Vieira Melo,Rafael Vilhena Reis Neto,Adriano Carvalho Costa,Rilke Tadeu Fonseca De Freitas,Ulisses Nascimento De Souza,Thiago Archangelo Freato

doi:10.4025/actascianimsci.v35i4.19807

<b>Direct and indirect effects of measures and reasons morphometric on the body yield of Nile tilapia, <i>Oreochromis niloticus</i></b> - doi: 10.4025/actascianimsci.v35i4.19807

Carlos Cicinato Vieira Melo, Rafael Vilhena Reis Neto + Show 4 more

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https://doi.org/10.4025/actascianimsci.v35i4.19807

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Abstract

The study was carried out with the objective of verifying which measures and morphometric ratios are more directly related to the body yield of Nile tilapia, Oreochromis niloticus, in two weight classes. Data were analyzed from 257 specimens of tilapia divided into two weight classes: p1 = 400 to 599 g and p2 = 600 to 900 g. The morphometric measurements standard length (SL), head length (HL), body height (BH) and body width (BW), and the ratios of these measures (HL / SL, BH / SL, BW / SL, HL / BH, BW / BH, BW / HL) were evaluated. The following body yields were calculated: carcass (RCAR), fillet (RFILE) and head (RCAB). The data were initially submitted to the stepwise procedure to eliminate problems of multicollinearity among the morphometric variables, then the correlations between the dependent variables (body yield) and the independent variables (measured and morphometric relationships) were calculated. Later, these correlations were divided into direct and indirect effects through path analysis, and the direct and indirect contributions of each variable measured in percentage terms. The morphometric ratio BW/HL, for both weight classes, was the variable most highly correlated and with the highest direct effect on RFILE and RCAB, showing to be the most important morphometric variable studied for tilapia carcass trait determination.

Highlights

The Nile tilapia Oreochromis niloticus is one of the main species cultivated commercially due to its good growth, its great potential for intensive fish farming, adaptation to different climates, tolerance to different environmental conditions, full field of cultivation techniques and a meat of excellent quality
The present study aimed to evaluate, through path analysis of phenotypic correlations, which morphometric variables were more directly related to the body yield of Nile tilapia (O. niloticus) in two weight classes
The morphometric measurements and ratios that contribute most to the variation in body yields were different for each class of slaughter weight (Table 2), which confirms the influence of weight on body measurements of fish in several studies (SHIBATTA; HOFFMANN, 2005; SANTOS et al, 2006; AYALA-PEREZ et al, 2008; SAHU et al, 2012)

Summary

Introduction

The Nile tilapia Oreochromis niloticus is one of the main species cultivated commercially due to its good growth, its great potential for intensive fish farming, adaptation to different climates, tolerance to different environmental conditions, full field of cultivation techniques and a meat of excellent quality. The present study aimed to evaluate, through path analysis of phenotypic correlations, which morphometric variables were more directly related to the body yield of Nile tilapia (O. niloticus) in two weight classes.

Results

Conclusion