Effects of dietary polyunsaturated fatty acid sources on expression of lipid-related genes in bovine milk somatic cells

© 2020, The Author(s). The objective of this study was to compare the effect of contrasting sources of dietary n-6 and n-3 PUFA on expression of genes related to lipid metabolism in dairy cows. During 63days, fifteen lactating cows were assigned to a control or basal diet containing no added lipid (n = 5 cows); and treatment diets supplemented with SO (n = 5 cows; unrefined soybean oil; 2.9% of DM) or FO (n = 5 cows; fish oil manufactured from salmon oil; 2.9% of DM). Plasma for fatty acid (FA) analysis and milk somatic cells (MSC) were obtained from all cows at the beginning of the study (day 0) and on days 21, 42 and 63. Plasma was used to determine FA transport dynamics. Compared with control and FO, plasma from SO had increased contents of C18:1 cis-9, C18:1 trans-11, C18:2 cis-9, trans-11 and total monounsaturated FA. On the other hand, compared with control and SO, FO increased plasma contents of C20:3 n-3, C20:3 n-6, C20:4 n-6, C20:5 n-3, C22:6 n-3 and total polyunsaturated FA. Moreover, plasma C18:3 n-3 and C20:5 n-3 increased over time for all diets. Compared with control, SO downregulated ACACA, INSIG1, and DGAT1, whereas FO downregulated ACACA, PPARGC1, LPIN1 and FABP3 on day 63, in MSC. At different time-points, SO and FO downregulated genes related to synthesis and intracellular transport of FA, synthesis of triglycerides, and transcription factors

Effects of dietary vegetable oils on mammary lipid-related genes in holstein dairy cows

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Effect of feeding cows with unsaturated fatty acid sources on milk production, milk composition, milk fatty acid profile, and physicochemical and sensory characteristics of ice cream

Simple Summary: The objective of this study was to evaluate the effects of supplementation of dairy cows' diets with different fatty acid (FA) sources on milk production, milk composition, milk fatty acid profile, and physicochemical and sensory characteristics of ice cream. Supplementation (3% dry matter (DM)) of diets with soybean oil (SO) and fish oil (FO) did not have detrimental effects on milk production, milk composition, or ice cream physicochemical and sensory characteristics. From a human standpoint, SO and FO improved the FA profile of milk. Abstract: The objective of this study was to evaluate the effects of supplementation of dairy cows with different fatty acid sources (soybean oil (SO) and fish oil (FO)) on milk production, milk composition, milk fatty acid profile, and physicochemical and sensory characteristics of ice cream. During 63 days, fifteen Holstein cows averaging 198 ± 35 days in milk were assigned to three groups: control diet with no added lipid (n = 5 cows); and supplemented diets with SO (n = 5 cows; unrefined SO; 30 g/kg DM) or FO (n = 5 cows; FO from unrefined salmon oil; 30 g/kg DM). Milk production, milk fat, and milk protein were not affected by treatments. Saturated fatty acids in milk fat were decreased with SO and FO compared with control. C18:2 cis-9, cis-12 was increased with SO whereas C18:2 cis-9, trans-11, C20:3n-3, C20:3n-6, C20:5n-3, and C22:6n-3 were the highest with FO. Draw temperature and firmness were higher in SO compared to control and FO ice creams. Melting resistance was higher in FO compared with control and SO ice creams. Supplementation of cow diets with SO and FO did not have detrimental effects on milk production, or ice cream physicochemical and sensory characteristics

Effect of olive oil in dairy cow diets on the fatty acid profile and sensory characteristics of cheese

The effect of dietary unrefined olive oil (OO) residues and hydrogenated vegetable oil (HVO) on the fatty acid profiles of milk and cheese and the sensory characteristics of cheeses was determined. For 9 weeks, animals were fed a control diet with no added lipid (n = 5 cows), or fat-supplemented diets containing OO or HVO (in both cases n = 5 cows; 30 g kg-1 dry matter). Compared with control and HVO, OO increased C18:1 cis-9, and C18:3 cis-9, cis-12, cis-15 fatty acids in milk; and also increased C18:1 trans-10, C18:1 trans-11, C18:1 cis-9, C18:2 cis-9, trans-11 and C18:3 cis-9, cis-12, cis-15 fatty acids in cheeses. OO reduced the number of holes, overall odour and acidity of cheeses, whereas HVO increased the cow milk odour, bitterness and acidity of cheeses. Overall, OO can improve the cheese fatty acid profile, but with adverse effects on sensory attributes