Carcass yield of Oreochromis niloticus deformed by inbreeding process evaluated by morphometry

Resumo

Genetic improvement is the main responsible for the increase in tilapia production in the last decades. However, the tools
used in broodstock selection have increased the mating of related animals, and as a consequence, animals with morphometric
anomalies have appeared. In view of the above, this work was carried out with the objective of evaluating the effect of body
deformities on the meat yield of tilapia. A total of 106 animals from assisted reproduction of the UFLA tilapia breeding
program were used, among which 53 had visible deformities. The animals were weighed, measured, and photographed with
a digital camera and had their body areas measured using computer software. Afterward, the animals were slaughtered and
the fillet from the left side was removed to measure weights and yields. On the right side, cuts were made to measure the
meat volume in the carcass. The residues were weighed separately to analyze processing losses. Using the software R-studio
the normality test was applied to all data and afterwards, the tests of means and correlations between morphometries and
yields were performed. No morphometric differences were identified between the groups, but deformed animals showed
smaller caudal areas and caudal peduncles and high correlations with fillet weight. However, normal fish showed higher
fillet yield and lower residue production. It is concluded that the anomalies imply lower filet yield and a higher amount of
processing residues.