Effect of abomasal infusions of geometric isomers of 10,12 conjugated linoleic acid on milk fat synthesis in dairy cows

Abstract

The trans-10,cis-12 isomer of conjugated linoleic acid (CLA) decreases TAG accumulation in 3T3-L1 adipocytes, reduces lipid accretion in growing animals, and inhibits milk fat synthesis in lactating mammals. However, there is evidence to suggest that other FA may also exert antilipogenic effects. In the current experiment, the effects of geometric isomers of 10,12 CLA on milk fat synthesis were examined using four Holstein-British Friesian cows in a 4 x 4 Latin Square experiment with 14-d periods. Treatments consisted of abomasal infusions of skim milk, or skim milk containing trans-10,cis-12 CLA (T1), trans-10,trans-12 CLA (T2), or a mixture of predominantly 10,12 isomers containing (g/l00 g) trans-10,cis-12 (35.0), cis-10,trans-12 (23.2), trans-10,trans-12 (14.9), and cis-10,cis-12 (5.1). CLA supplements were prepared from purified ethyl linoleate and infused as nonesterified FA. Infusions were conducted over a 4-d period with a 10-d interval between treatments and targeted to deliver 4.5 g/d of 10,12 CLA isomers. Compared with the control, trans-10, trans-12 CLA had no effect (P> 0.05) on milk fat yield, whereas treatments T1 and T3 depressed (P <0.05) milk fat content (19.8 and 22.9%, respectively) and decreased milk fat output (20.8 and 21.3%, respectively). Comparable reductions in milk fat synthesis to 4.14 and 1.80 g trans-10,cis-12/d supplied by treatments T1 and T3 indicate that other 10,12 geometric isomers of CLA have the potential to exert antilipogenic effects. The relative abundance of cis-10,trans-12 CLA in treatment T3 and the low transfer efficiency of this isomer into milk suggest that cis-10,trans-12 CLA was the active component..Peer reviewe

Effect of subacute ruminal acidosis on milk fat concentration, yield and fatty acid profile of dairy cows receiving soybean oil

“…Recent studies confirmed that trans -10, cis -12 CLA can be synthesized from LA when incubated with Probionibacterium acnes and mixed ruminal bacteria (Wallace et al 2007) and in-vivo (Shingfield et al 2008). Other CLA such as cis -10, trans -12 CLA (Sæbø et al 2005) and trans -9, cis -11 CLA (Perfield et al 2007), both intermediates of LA (Wallace et al, 2007), were suggested as antilipogenic. Furthermore, trans -10, trans -12 CLA (Sæbø et al 2005) and trans -9, trans -11 CLA (Perfield et al 2007) showed no effect on lipogenesis but caused a decrease in Δ 9 -desaturation indices.…”

“…Other CLA such as cis -10, trans -12 CLA (Sæbø et al 2005) and trans -9, cis -11 CLA (Perfield et al 2007), both intermediates of LA (Wallace et al, 2007), were suggested as antilipogenic. Furthermore, trans -10, trans -12 CLA (Sæbø et al 2005) and trans -9, trans -11 CLA (Perfield et al 2007) showed no effect on lipogenesis but caused a decrease in Δ 9 -desaturation indices. The trans 18:1 intermediates investigated include trans -9 (Rindsig & Schultz, 1974), trans -11, and trans -12 (Griinari et al 2000).…”

“…Bauman & Griinari (2001, 2003) proposed the biohydrogenation theory which states that: intermediates resulting from altered ruminal biohydrogenation (BH) under specific dietary conditions act on the mammary gland, thus inhibiting de novo synthesis of FA. The role of trans -10, cis -12 conjugated linoleic acid (CLA) (Baumgard et al 2000) and cis -10, trans -12 CLA (Sæbø et al 2005) as potent inhibitors of FA synthesis in the mammary gland have been confirmed. Additional BH intermediates such as trans -9, cis -11 CLA (Perfield et al 2007) and trans -10 18:1 (Shingfield et al 2009) were identified as antilipogenic, nonetheless, more studies are needed to confirm their role in MFD.…”

Effect of sunflower-seed oil or linseed oil on milk fatty acid secretion and lipogenic gene expression in goats fed hay-based diets

“…Post-ruminal infusion studies have established that several metabolites formed during ruminal 18:2 n -6 metabolism (Shingfield & Griinari, 2007) including trans -10, cis -12 CLA (Baumgard et al 2000), trans -10, trans -12 CLA (Sæbø et al 2005) and trans -9, trans -11 CLA (Perfield et al 2007) decrease product substrate concentration ratios for SCD in milk in the bovine. Trans -10, cis -12 CLA is also known to elicit a decrease in the fatty acid concentration ratios that serve as a proxy for SCD in the goat (Andrade & Schmidely, 2006).…”

Pilot‐Scale Production of Conjugated Linoleic Acid‐Rich Soy Oil by Photoirradiation

“…The cis‐trans ‐, trans‐cis CLA group consists of cis ‐9 trans ‐11 CLA, trans ‐10 cis ‐12 CLA, trans ‐9 cis ‐11 CLA, and cis ‐10 trans ‐12 CLA isomers. Trans ‐9 cis ‐11 CLA and cis ‐10 trans ‐12 CLA have shown to exert antilipogenic effects (Sæbø and others 2005; Perfield and others 2007). Thus, these 4 isomers have been reported together as a group.…”