Effect of high-oil corn or added corn oil on ruminal biohydrogenation of fatty acids and conjugated linoleic acid formation in beef steers fed finishing diets

Abstract

Three Angus steers (410 kg) cannulated in the proximal duodenum were used in a replicated 3 x 3 Latin square to evaluate the effects of dietary lipid level and oil source on ruminal biohydrogenation and conjugated linoleic acid (CLA) outflow. Dietary treatments included: 1) typical corn (TC; 79.2% typical corn), 2) high-oil corn (HOC; 79.2% high-oil corn), and 3) the TC diet with corn oil added to supply an amount of lipid equal to the HOC diet (OIL; 76.9% TC + 2.4% corn oil). Duodenal samples were collected for 4 d following 10-d diet adaptation periods. Data were analyzed with animal, square, period, and treatment in the model and planned, nonorthogonal contrasts were used to test the effects of dietary lipid content (TC vs HOC and OIL) and oil source (HOC vs OIL) on ruminal biohydrogenation. Intake and duodenal flow of total long-chain fatty acids were increased (P < 0.05) by over 63% for diets containing more lipid regardless of oil source. Apparent ruminal dry matter and long chain fatty acid digestibilities were not altered (P > 0.05) by dietary lipid level or oil source. Ruminal biohydrogenation of total and individual 18-carbon unsaturated fatty acids was greater (P < 0.05) for diets with higher lipid content. Biohydrogenation of oleic acid was greater (P < 0.05) for HOC than OIL, but biohydrogenation of linoleic acid was lower (P < 0.05) for HOC than OIL. Duodenal flows of palmitic, stearic, oleic, linoleic, and arachidic acids were more than 30% greater (P < 0.05) for diets containing more lipid. Flow of all trans-octadecenoic acids was greater (P < 0.05) for diets containing more lipid. Corn oil addition increased (P < 0.05) the flow of trans-10 octadecenoic acid and the trans-10, cis-12 isomer of CLA by threefold compared to feeding high-oil corn. Feeding high-oil corn or adding corn oil to typical corn rations increased intake, biohydrogenation, and duodenal flow of unsaturated long-chain fatty acids. Compared with high-oil corn diets, addition of corn oil increased duodenal flow of trans-10, trans-12 and cis-12 isomers of octadecenoic acid and the trans-10, cis-12 isomer of CLA. The amount of cis-9, trans-11 isomer of conjugated linoleic acid flowing to the duodenum was less than 260 mg/d, a value over 20 times lower than flow of trans-11 vaccenic acid indicating the importance of tissue desaturation for enhanced conjugated linoleic acid content of beef.

Production of trans C18:1 and conjugated linoleic acid in continuous culture fermenters fed diets containing fish oil and sunflower oil with decreasing levels of forage

“…In ewes, duodenal flow of t10c12 CLA increased and c9t11 CLA decreased in response to graded increments of dietary concentrate with a constant level (7.4 g/100 g diet DM) of supplemental FA from soya-bean oil (Kucuk and Hess, 2004). Our results support the findings of others (Beaulieu et al, 2002;Duckett et al, 2002;Shingfield et al, 2005) that high concentrate diets support t10c12 CLA formation in the rumen. Replacing incremental portions of red clover with maize grain in dual-flow continuous cultures resulted in a linear increase in the output of t10c12 CLA into effluent (Latham et al, 1972).…”

“…The decreased biohydrogenation of linoleic and linolenic acids with the LF diet suggested a lower biohydrogenation activity by cultures microbes. The low biohydrogenation values for oleic acid in this study compared with others (Duckett et al, 2002;Sackmann et al, 2003Kucuk andHess, 2004) may have resulted from the DHA effect on the reduction step in the biohydrogenation (AbuGhazaleh and Jenkins, 2004).…”

“…Trans10c12 CLA is a potent inhibitor of fat synthesis . What seems evident from this study and others (Beaulieu et al, 2002;Duckett et al, 2002;Kucuk and Hess, 2004) is that a high linoleic acid oil source along with low dietary F:C ratio has the greatest potential to increase t10c12 CLA. The t11t13 CLA was the second predominant isomer in the LF.…”

Conjugated linolenic acid (CLnA), conjugated linoleic acid (CLA) and other biohydrogenation intermediates in plasma and milk fat of cows fed raw or extruded linseed

“…FAs in plasma lipids extracts and in unextracted diet ingredients and milk samples were methylated using sodium methoxide followed by boron trifluoride as described by Park and Goins (1994). This method, which successively uses basic and acid transmethylations, allows methylation of all lipid classes, including non-esterified fatty acids, and does not alter the stereochemistry of CLA double-bonds (Duckett et al, 2002 For plasma analysis, flame ionisation detector temperature was maintained at 2608C and the injector at 2558C, and a splitless injection with an automatic injector was used. Helium was the carrier gas with a constant pressure (24.6 p.s.i.).…”

Production of Lean Beef Containing a High Content oftrans-10,cis-12Conjugated Linoleic Acid by Feeding a High-Temperature-Micro-Time-Treated Diet with Extruded Soybean

“…35) Many studies have reported that dietary supplementation with a linoleic acid-rich oil such as corn oil, 36) soybean oil 37) or safflower oil 38) increased the concentration of CLA in the ruminant. Similarly, in the present study using high-quality ESB, and the total CLA concentration in the body fat was significantly higher in the HTMT-treated and non-HTMT-treated dietary groups than in the control group.…”