Relationship between adipose maturity and fatty acid composition in various adipose tissues of Japanese Black, Holstein and Crossbred (F1) steers

Abstract

The amount of monounsaturated fatty acid (MUFA) is intimately related to adipose softness, melting point (MP) and flavor in beef. Stearoyl-CoA desaturase (SCD) is a main gene involved in MUFA synthesis. Mature adipose tends to be highly saturated, whereas immature or maturing adipose is highly unsaturated when chronologically based, so the degree of non-saturation can be an index of adipose maturity. In this study, three different adipose tissues (coelomic (CL), perirenal (PR), and subcutaneous (SC)) from three beef breeds with differing slaughter ages (Japanese Black (29.5 months), Holstein (20.1 month), and F1 crossbreed (25.6 months)) were examined to: (i) determine adipose maturity level as indexed by MUFA %; and (ii) determine SCD and other lipogenic gene messenger RNA (mRNA) expression levels in relation to unsaturated fatty acid content. Fatty acid composition was significantly different between adipose tissues (P < 0.05). MUFA amount was high in the following order: SC > CL > PR. This pattern corresponded to SCD mRNA expression profile showing higher expression in SC than CL and PR. However, Japanese black cattle are an exception with CL adipose containing similar UFA % as SC adipose, yet having the lowest SCD mRNA expression level among all adipose tissues tested. Therefore, SCD mRNA expression and MUFA % appear to be directly related; however, differences in SCD mRNA expression among three adipose tissues may reflect differences in the fat development characteristics affected by chronological age of the cattle breeds.

Fatty acid composition of beef steers as affected by diet and fat depot

“…These findings agree with differences in Δ-9 desaturase indices (Jiang et al, 2013) and mRNA abundance (Lee et al, 2011) reported previously. The proportions of 22:5n-3 and 20:4n-6 were the only n-3 and n-6 PUFA influenced by fat depot, with SCF having larger (P <0.05) proportions of these FA compared with PRF (Table 3).…”

“…These dissimilarities could be linked to the proportions of 18:0, which exhibit a similar pattern. Generally, less mature fat depots situated externally, such as SCF, are less saturated than mature fat depots situated internally, such as PRF (Christie, 1978;Lee et al, 2011;Jiang et al, 2013). This is linked to a greater Δ-9 desaturase activity index in external depots as opposed internal ones, and replacement of 18:0 with c9-18:1 in external fat depots.…”

“…These proportions were accentuated (P <0.05) by feeding SS, maintained (P > 0.05) by feeding DDGS-15, and attenuated (P <0.05) by feeding the DDGS-30 diet. This could be the result of a combination of factors including lower Δ-9 desaturase activity indices in PRF vs. SCF (Lee et al, 2011;Jiang et al, 2013), higher dietary 18:2n-6 observed for the diets containing SS, greater bypass of 18:2n-6 when feeding DDGS diets, and a decline in dietary fibre with increasing levels of DDGS, which might have reduced ruminal pH and negatively influenced biohydrogenation in the rumen (Hristov et al, 2005;Felix et al, 2012). It may also be due to greater de novo synthesis of FA in SCF and dilution of PUFA-BHP when DDGS were added to the diet.…”

Differential Expression of &lt;italic&gt;PPARγ&lt;/italic&gt;, &lt;italic&gt;FASN&lt;/italic&gt;, and &lt;italic&gt;ACADM&lt;/italic&gt; Genes in Various Adipose Tissues and &lt;italic&gt;Longissimus dorsi&lt;/italic&gt; Muscle from Yanbian Yellow Cattle and Yan Yellow Cattle

“…The beef performance index (BPI) is 5.66 to 6.76 kg/cm for adult bulls and 4.06 to 4.59 kg/cm for adult cows over Yanbian yellow cattle. Fat percentages in carcass are different between different cattle breeds and fat depots in the bovine body are developed according different order (Lee et al, 2011). …”

Evaluation of the thermal property of bovine intramuscular adipose tissue using differential scanning calorimetry

“…On the other hand, there was no correlation between the MUFA content and the EP (R 2 = 0.040). A high MUFA concentration and lower MP in adipose tissue contributes to a desirable beef flavor (Yang et al 1999;Lee et al 2011), while a higher PUFA and MUFA in adipose tissue contribute to a lower fat MP (Smith et al 1998;Pitchford et al 2002;De Smet et al 2004;Daley et al 2010;Uemoto et al 2010). These reports strongly support the MP measured using the slip point method that would be reflected in the MUFA content in IAT.…”