Analysis of carcass traits, meat quality, amino acid and fatty acid profiles between different duck lines

Abstract

To investigate the effect of genetic selection on meat quality in ducks, twenty of each fast growth ducks (LCA) and slow growth ducks (LCC) selected from F6 generation of Cherry Valley ducks (♂) x Liancheng white ducks (♀) were analyzed for carcass characteristics, meat quality (physicochemical and textural characteristics), amino acid and fatty acid profiles at 7 wk. Results showed that live body weight, slaughter weight, eviscerated yield and abdominal fat percentage of LCA were significantly higher than those in LCC ducks (P < 0.01). Moreover, the average area and diameter of myofiber were larger in LCA than LCC ducks (P < 0.01). The breast and thigh muscles of LCA exhibited significantly lower water holding capacity and thermal loss compared with LCC ducks (P < 0.01). In addition, the content of nonessential amino acids (Glu, Asp, and Arg) in breast muscles and Asp, Ser, Thr, and Met in thigh muscles was higher in LCC than LCA ducks (P < 0.05). The proportion of polyunsaturated fatty acids (PUFA) in breast muscles of LCC was higher than LCA ducks (P < 0.05). However, the content of saturated fatty acids (SFA) in breast and thigh muscles of LCA was higher compared with LCC ducks (P < 0.05). The proportion of monounsaturated fatty acids (MUFA) in thigh muscles was significantly higher in LCC compared with LCA ducks (P < 0.01). Finally, multiple traits were evaluated by applying principal component analysis (PCA) and the results indicated that PUFA and SFA in breast muscles of LCA played important roles in meat quality, followed by Warner-Bratzler shear force (WBSF) and MUFA. However, water holding capacity (WHC) had a dominant effect in meat quality of thigh muscles in both LCA and LCC ducks.

Keywords: amino acid profile; ducks; meat quality; myofiber type; skeletal muscle.

Figure 1

The morphology of myofibers in LCA and LCC. (A) Hematoxylin and eosin staining in breast muscles (BM) and thigh muscles (TM) from LCA and LCC. Magnification of 200 × was used (Bar = 100 μm). Analysis of muscle fiber diameter (B) and muscle fiber cross-sectional area (C) was conducted. Vertical bars represent mean ± standard error (n = 3). P < 0.01 is shown as **.

Figure 2

The type of muscle fibers in LCA and LCC. Immunohistochemical analyses for breast muscle (A) and thigh muscle (B) using anti-fast (MYH1A) and anti-slow (MYH7B) myosin skeletal heavy chain (Bar = 100 μm). Red arrows point to myofibers with positive immunostaining for glycolytic fibers; Green arrows point to myofibers with positive immunostaining for oxidative fibers.

Figure 3

Relative mRNA expression of myosin heavy chain (MyHC) isoform genes in LCA and LCC. The mRNA expression of Myh1a, type IIb, fast-twitch (A), Myh1b, type IIa, fast-twitch (B) and Myh7b, type I, slow-twitch (C) was measured. The given values are reported as means ± standard error (n = 3). P < 0.05 is shown as *; p < 0.01 is shown as **.

Figure 4

Projection of one individual of each breed in the plane defined by the 2 principal components. Each black dot represents 1 individual of LCA and each red dot represents 1 individual of LCC.

Figure 5

Different colored dots represent different meat quality parameters. PCA scores plot of meat traits for breast muscle in LCA (A) and LCC (B), and thigh muscle in LCA (C) and LCC (D). EAA, essential amino acid; FAA, flavor amino acid; MUFA, monounsaturated fatty acid; PUFA, polyunsaturated fatty acid; SFA, saturated fatty acid; WBSF, Warner-Bratzler shear force; WHC, water holding capacity.