Dietary Marine Algae (Schizochytrium sp.) Increases Concentrations of Conjugated Linoleic, Docosahexaenoic and Transvaccenic Acids in Milk of Dairy Cows

Abstract

Modification of milk fat to contain long-chain (n-3) fatty acids and increased concentrations of conjugated linoleic acid has potential for improving health of consumers. Natural modification of milk through nutritional manipulation of diets for dairy cows is preferable to post-harvest modification. The objectives of this study were to increase the concentrations of beneficial fatty acids in milk fat by feeding a diet rich in (n-3) fatty acids from algae to dairy cows. Cows were fed a control diet, a diet containing algae (Schizochytrium sp.) protected against ruminal biohydrogenation, or a diet containing unprotected algae for 6 wk. Feed intake and milk production were recorded daily. Milk samples were obtained weekly for analysis of milk composition and profile of fatty acids. Percentage of fat in milk of cows fed algae was lower (P < 0.01) than in milk from cows fed the control diet; however, energy-corrected milk production did not differ (P > 0.05). Inclusion of algae in diets decreased (P < 0.01) feed intake. Milk fat from cows fed algae contained greater (P < 0.01) concentrations of conjugated linoleic acid, (n-3) fatty acids (particularly docosahexaenoic acid), and transvaccenic acid. Concentrations of docosahexaenoic acid were greater (P < 0.01) in milk fat from cows fed protected algae compared to milk fat from cows fed unprotected algae. Milk fat from cows fed algae contained lower (P < 0.05) concentrations of total saturated fatty acids compared to cows fed the control diet. In conclusion, milk fat can be modified through nutritional management of dairy cows to provide more favorable fatty acids for consumers.

Omega-3 supplementation, milk quality and cow immune-competence

“…These results are in contrast with other authors (Franklin et al, 1999;Vahamani et al, 2013) who found a significant change in milk fatty acid composition from cows fed marine algae, with increased total UFA and decreased SFA levels.…”

“…Similarly, Moate et al (2013), offering different amounts of algal meal to lactating cows, found no alterations on milk yield although milk fat yield decreased with the addition of DHA. On the contrary, other authors (Franklin et al, 1999;Boeckaert et al, 2008;Hostens et al, 2011), supplementing cows with unprotected marine algae observed a reduction in dry matter intake (DMI) and milk yield. In general, a large amounts of fat in the diet of ruminants, and particularly high level of PUFA in unprotected form, is not recommended, as it has a negative effect on the activity of the rumen microflora, with changes in the pattern of rumen biohydrogenation that leads to accumulation of trans FA in the rumen, and inhibition of milk fat synthesis in the mammary gland (Bauman and Griinari, 2003).…”

“…Marine oils are rich in long-chain (C20-C22) PUFA, of which EPA and/or DHA are the most important (Arab-Tehrany et al, 2012). The effect of feeding marine algae is slightly different, with increases in milk DHA and docosapentaenoic acid (DPA) (22:5 n-3), as well as in C22:5 n-6 and C20:4 n-6, but not in EPA (Barclay et al, 1998;Franklin et al, 1999). This particular effect of marine algae is related to their FA composition.…”

Recovery of dairy manure nutrients by benthic freshwater algae

“…In addition, milk from dairy cows fed a diet supplemented with the marine alga Schizochytrium sp. showed an increase in omega-3-fatty acid content, a characteristic that has potential for improving consumer health (Franklin et al, 1999). The algal biomass could also be used as a slow-release fertilizer, either sprayed as a suspension directly on croplands or harvested and stored until conditions are favorable for spreading on the fields.…”

Consolidated Properties and New Perspectives for Polyunsaturated Fatty Acids in Ruminant Diet

“…12 Other aspects, both economic and environmental, have to be taken in account when using fish oil as a source of n-3 PUFA, such as the relevant cost and the sustainability of fish stocks. 1 Therefore, it is crucial to consider alternative sources, for example marine algae rich in DHA, 8,13,14 linseed 15 and camelina 16,17 both rich in C18:3 n-3 (ALA, alpha-linolenic acid), the precursor for EPA and DHA. Another natural dietary source of n-3 PUFA is green pasture.…”