Feeding Fish Meal and Extruded Soybeans Enhances the Conjugated Linoleic Acid (CLA) Content of Milk

Abstract

Twelve multiparous Holstein cows averaging 65 (33 to 122) DIM were used in a 4 x 4 Latin square for 4-wk periods to determine whether feeding fish oil as fish meal would stimulate increased amounts of milk conjugated linoleic acid (cis-9, trans-11 C18:2; CLA) and transvaccenic acid (trans-11 C18:1; TVA) when the cows were fed extruded soybeans to supply additional linoleic acid. Treatment diets were 1) control; 2) 0.5% fish oil from fish meal; 3) 2.5% soybean oil from extruded soybeans; and 4) 0.5% fish oil from fish meal and 2% soybean oil from extruded soybeans. Diets were formulated to contain 18% crude protein and were composed (dry basis) of 50% concentrate mix, 25% corn silage, and 25% alfalfa hay. Intake of DM was not affected by diet. Milk production was increased by diets 2, 3, and 4 compared with diet 1 (control). Milk fat and milk protein percentages decreased with diets 3 and 4. Milk fat yield was not affected by treatments, but yield of milk protein was increased with supplemental fish meal and extruded soybeans or their blend. When diets 2, 3, or 4 were fed, concentrations of cis-9, trans-11 CLA in milk fat increased by 0.4-, 1.4-, and 3.2-fold, and TVA concentrations in milk fat increased by 0.4-, 1.8-, and 3.5-fold compared with the control milk fat. Increases in TVA and cis-9, trans-11 CLA were 91 to 109% greater when a blend of fish meal and extruded soybeans was fed than the additive effect of fish meal and extruded soybeans. This suggested that fish oil increased the production of CLA and TVA from other dietary sources of linoleic acid such as extruded soybeans.

Effect of fatty acid calcium salts from linseed oil on the yield and n-3 fatty acid content of milk and on blood plasma parameters of cows

“…In the research conducted so far, cis fatty acids have been the main object of study in addition to the rumen synthesis of CLA C18:2 (Abuhazaleh et al, 2002;Brzóska, 2005).…”

Effects of pistachio by-products in replacement of alfalfa hay on ruminal fermentation, blood metabolites, and milk fatty acid composition in Saanen dairy goats fed a diet containing fish oil

“…Milk fatty acid composition has been shown to be affected by dietary oil supplementation (Huang et al 2008). A number of studies have also demonstrated that dietary fish oil supplements alter the pathways of ruminal biohydrogenation, and lead to the accumulation of trans-11 C18:1 in milk (Abu-Ghazaleh et al 2002;Whitlock et al 2002). Donovan et al (2000) reported that dietary inclusion of fish oil (20 g/kg of diet DM) increased cis-9, trans-11 conjugated linoleic acid concentrations in milk.…”

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

“…Previous studies have demonstrated an increase in the vaccenic acid (VA) and c9t11 CLA content of bovine milk fat when fish oil (FO) and linoleic acid oil sources were added to dairy cattle rations containing 50% forage (AbuGhazaleh et al, 2000;Whitlock et al, 2002). Studies examining the effect of forage or concentrate feeding on the distribution of trans C18:1 and CLA isomers in the rumen (Loor et al, 2004a) or ruminant fat (Sackmann et al, 2003;Aharoni et al, 2004;Loor et al, 2005) have used only vegetable oils or FO.…”

“…Alterations in the profile of trans C18:1 intermediates formed in the rumen have direct consequences on the supply of VA available for endogenous conversion in the mammary gland into c9t11 CLA . Previously, AbuGhazaleh et al (2000AbuGhazaleh et al ( , 2003 and Whitlock et al (2002) demonstrated that the greatest concentrations of VA and c9t11 CLA in milk fat and rumen contents can be obtained by adding FO along with linoleic acid fat source to ruminant animals' diet. The aim of this study was to investigate how changing dietary forage levels in diets containing FO and sunflower oil (SFO) affect trans C18:1 and CLA isomers distribution in the rumen.…”