Changes in the proximate and fatty acid composition in carp meat during the semi intensive farming

Dejana Trbović; Zoran Marković; Radivoj Petronijević; Milan Milijašević; Danka Spirić; Danijela Vranić; Aurelija Spirić

Dejana Trbović Institute of meat hygiene and technology
Zoran Marković University in Belgrafde - Faculty of Agricultural Science
Radivoj Petronijević Institute of meat hygiene and technology
Milan Milijašević Institute of meat hygiene and technology
Danka Spirić Institute of meat hygiene and technology
Danijela Vranić Institute of meat hygiene and technology
Aurelija Spirić Institute of meat hygiene and technology

Keywords: carp, semi intensive farming, proximate composition, fatty acids, analysis of variance (ANOVA), Principal component analysis (PCA), Linear discrimination analysis (LDA)

Abstract

The aim of this study was to examine and evaluate the proximate composition and fatty acid proﬁ les of carp (Cyprinus carpio) during rearing in the semi-intensive farming conditions, supplementary fed extruded feed. Carp at the age of two years was submitted to trials, from spring to autumn, at the ﬁsh farm „Ečka“AD. Samples of carp were collected in April, June, September and October. The protein content in ﬁ sh sampled in September was signiﬁ cantly different from the protein content in ﬁ sh sampled in April, June and October (p < 0.001), (17.48%, 17.27%, 18.28% and 17.26%, respectively). The quantities of total lipids slightly increased (2.25%, 2.37%, 3.02% and 4.72%, respectively) with the increase of the ﬁ sh weight (598 g, 874 g, 1439 g and 1984 g, respectively), but signiﬁ cant increases occurred between September and October (p < 0.001). The moisture content decreased (79.55%, 78.86%, 77.46% and 75.72%, respectively). Principal Component Analysis (PCA) and Linear Discrimination Analysis (LDA) indicated that there were signiﬁcant changes in the fatty acid composition of carp during growth. Starting from April to October the quantities of fatty acids were as follows: SFA (saturated fatty acids) – 28.47%, 28.97%, 24.86% and 23.66%, respectively; MUFA (monounsaturated fatty acids) – 38.57%, 40.52%, 41.68% and 42.43%, respectively; PUFA (polyunsaturated fatty acids) – 32.53%, 30.49%, 31.53% and 32.55%, respectively.
The additional feeding of carp with the extruded feed inﬂuenced the increase in quantities of MUFA and n-6 PUFA (24.98%, 22.86%, 26.96% and 27.99%, respectively), and the decrease in quantities of the nutritionally important n-3 PUFA (5.13%, 6.59%, 4.57% and 4.57%, respectively). The highest n-3/n-6 ratio was obtained in June (0.30) and the lowest in October (0.16), indicating that the applied extruded feed was rich in n-6 and poor in n-3 PUFA. PCA and LDA have shown that signiﬁcant changes in the fatty acid composition of carp during the breeding occured. Separation of the carp according to the sampling period was achieved by the LDA analysis, which is consistent with the type of ingested food.