Abomasal or ruminal administration of flax oil and hulls on milk production, digestibility, and milk fatty acid profile of dairy cows

Abstract

Four ruminally fistulated primiparous lactating Holstein cows were assigned to a 4 × 4 Latin square design to determine the effects of the site of administration (rumen or abomasum) of flax oil and flax hulls on diet digestibility and milk fatty acid profile of dairy cows. The treatments were 1) oil and hulls administered in the rumen and abomasal infusion of water (RUM/RUM), 2) oil and hulls infused in the abomasum (ABO/ABO), 3) oil administered in the rumen and hulls infused in the abomasum (RUM/ABO), and 4) oil infused in the abomasum and hulls placed in the rumen (ABO/RUM). Cows on the ABO/ABO and RUM/RUM treatments had the highest and lowest amounts of basal dry matter eaten, respectively. Higher dry matter digestibility was obtained when flax oil bypassed the rumen (ABO/ABO and ABO/RUM) compared with when flax oil was administered directly in the rumen (RUM/ABO and RUM/RUM). Apparent digestibility of ether extract was higher when flax hulls were administered in the rumen (RUM/RUM and ABO/RUM) compared with when flax hulls were infused in the abomasum (ABO/ABO and RUM/ABO). The lowest digestibility of acid detergent fiber and neutral detergent fiber was obtained when both flax products were added in the rumen, which may be attributed to the high amount of oil present in the rumen (7.8% of total dry matter input). The lowest yield of 4% fat-corrected milk was obtained for cows on the RUM/RUM treatment, probably as a result of lower dry matter intake and digestibility of fiber. Milk concentrations of protein, fat, total solids, and lactose were similar among treatments. Administration of oil and hulls in the rumen resulted in the highest concentrations of intermediate products of biohydrogenation and total trans fatty acids in milk fat compared with the other treatments. All ratios of n-6 to n-3 fatty acids in milk fat were lower than the 4 to 1 ratio recommended to improve human health. These results suggest that the presence of both flax oil and flax hulls in the rumen decreases 4% fat-corrected milk yield and digestibility but provides a desirable fatty acid profile of milk to enhance consumers' health.

Effect of camelina oil or live yeasts (Saccharomyces cerevisiae) on ruminal methane production, rumen fermentation, and milk fatty acid composition in lactating cows fed grass silage diets

“…When fed as part of a TMR based on grass hay, linseed oil (40 g/kg of diet DM) had no negative effects on nutrient digestion (Benchaar et al, 2012), whereas linseed oil or whole or processed linseeds supplying 57 g of lipid/kg of diet DM lowered total-tract OM and NDF digestibility in cows fed maize silage-based diets . In cows fed a diet based on grass and maize silage, supplemental lipid from linseed oil (400 g/d) and linseed hulls (1.8 kg/d containing 29.4 g of fat/kg of DM) had more adverse effects on intake and total-tract fiber digestibility when administered in the rumen than the abomasum (Kazama et al, 2010). Direct comparisons are limited, but at low levels of inclusion (10 g/kg of DM), no differences in total-tract nutrient digestion have been reported for camelina oil compared with rapeseed or sunflower oil in cows fed red clover silage (Halmemies-Beauchet-Filleau et al, 2011).…”

Effects of supplementation of flax meal and flax oil on mammary gene expression and activity of antioxidant enzymes in mammary tissue, plasma and erythrocytes of dairy cows

“…Therefore, understanding the regulation of milk fat synthesis is central to the development of nutritional strategies to enhance the nutritional value of milk and improve the energy balance of lactating ruminants (Shingfield et al, 2010). Supplying rumen bypass vegetable oils to dairy cows changes milk composition and enhances the concentration of polyunsaturated fatty acids (FA) in milk fat (Litherland et al, 2005;Kazama et al, 2010;Côrtes et al, 2011). However, supplemental fat rich in polyunsaturated FA and oilseeds impact cellular processes affecting many physiological systems.…”

Recent developments in altering the fatty acid composition of ruminant-derived foods

“…Compared Figure 4 Relationship between the amount of 18:2n-6 (K) or 18:3n-3 (J) infused at the abomasum and mammary secretion of 18:2n-6 and 18:3n-3 in lactating cows. Data derived from experiments involving infusions of examining the effects of post-ruminal infusion of soya oil (Litherland et al, 2005), soya fatty acids (Litherland et al, 2005;Ortiz-Gonzalez et al, 2007) and linseed oil (Petit et al, 2002;Kazama et al, 2010). Solid line indicates the relationship:-18:2n-6 milk 5 0.488 3 18:2n-6 infused 1 17.67 (n 5 11, R 2 5 0.968, P , 0.001) and the dotted line indicates the relationship:-18:3n-3 milk 5 0.499 3 18:3n-3 infused 1 3.55 (n 5 11, R 2 5 0.942, P , 0.001).…”