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

Abstract

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