Use of algae or algal oil rich in n-3 fatty acids as a feed supplement for dairy cattle

Abstract

Fish oil is used as a ration additive to provide n-3 fatty acids to dairy cows. Fish do not synthesize n-3 fatty acids; they must consume microscopic algae or other algae-consuming fish. New technology allows for the production of algal biomass for use as a ration supplement for dairy cattle. Lipid encapsulation of the algal biomass protects n-3 fatty acids from biohydrogenation in the rumen and allows them to be available for absorption and utilization in the small intestine. Our objective was to examine the use of algal products as a source for n-3 fatty acids in milk. Four mid-lactation Holsteins were assigned to a 4×4 Latin square design. Their rations were supplemented with 1× or 0.5× rumen-protected (RP) algal biomass supplement, 1× RP algal oil supplement, or no supplement for 7 d. Supplements were lipid encapsulated (Balchem Corp., New Hampton, NY). The 1× supplements provided 29 g/d of docosahexaenoic acid (DHA), and 0.5× provided half of this amount. Treatments were analyzed by orthogonal contrasts. Supplementing dairy rations with rumen-protected algal products did not affect feed intake, milk yield, or milk component yield. Short- and medium-chain fatty acid yields in milk were not influenced by supplements. Both 0.5× and 1× RP algae supplements increased daily milk fat yield of DHA (0.5 and 0.6±0.10 g/d, respectively) compared with 1× RP oil (0.3±0.10 g/d), but all supplements resulted in milk fat yields greater than that of the control (0.1±0.10g/d). Yield of trans-18:1 fatty acids in milk fat was also increased by supplementation. Trans-11 18:1 yield (13, 20, 27, and 15±3.0 g/d for control, 0.5× RP algae, 1× RP algae, and 1× RP oil, respectively) was greater for supplements than for control. Concentration of DHA in the plasma lipid fraction on d 7 showed that the DHA concentration was greatest in plasma phospholipid. Rumen-protected algal biomass provided better DHA yield than algal oil. Feeding lipid-encapsulated algae supplements may increase n-3 content in milk fat without adversely affecting milk fat yield; however, preferential esterification of DHA into plasma phospholipid may limit its incorporation into milk fat.

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

“…This result is in agreement with Stamey et al (2012) who found no detrimental influence on milk yield or milk fat yield in Holstein cows receiving rumen protected algal biomass or rumen protected algal oil. In the present study the form of algae supplementation was protected similarly to that used by Stamey et al (2012).…”

“…This result is in agreement with Stamey et al (2012) who found no detrimental influence on milk yield or milk fat yield in Holstein cows receiving rumen protected algal biomass or rumen protected algal oil. In the present study the form of algae supplementation was protected similarly to that used by Stamey et al (2012). 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.…”

“…In addition, the transfer efficiency of UFA from diet to milk can be due to the stage of lactation as Kennelly (1996) reported different effects of feeding whole canola seeds on fatty acid composition of milk as function of calving distance. In the present study, the low DHA increase obtained in milk by algae supplementation may be due to the later stage of lactation of the cows used in the experiment (Stamey et al, 2012). As previously found in cows supplemented with marine algae (Stamey et al, 2012;Vahamani et al, 2013), the concentration of trans-18:1 was significantly greater in supplemented groups (2.51±0.02% and 2.83±0.02% vs 2.12±0.02%, for D, E and C groups respectively; P<0.05).…”

“…In the present study, the low DHA increase obtained in milk by algae supplementation may be due to the later stage of lactation of the cows used in the experiment (Stamey et al, 2012). As previously found in cows supplemented with marine algae (Stamey et al, 2012;Vahamani et al, 2013), the concentration of trans-18:1 was significantly greater in supplemented groups (2.51±0.02% and 2.83±0.02% vs 2.12±0.02%, for D, E and C groups respectively; P<0.05). Although algal DHA was rumen-protected, the increase in trans-C18:1 percentage in milk FA observed in milk from E and D groups suggests that supplementation can inhibit the last step of ruminal hydrogenation from trans-C18:1 to C18:0.…”

“…The little increase observed may be probably due to the transfer efficiency of DHA from the diet to the milk. In fact, with the exception of Kitessa et al (2004) who reported a DHA transfer of 18% with rumen protected tuna oil, Franklin et al (1999) reported DHA transfer efficiencies of 8% and 16% with unprotected and protected algal supplements, respectively; Boeckaert et al (2008) found transfer efficiencies of 5.9 and 3.1% in early and late lactation, respectively, while Stamey et al (2012) observed a transfer efficiency of 2%. Lower transfer efficiency may be due to biohydrogenation in the rumen and to the length of the supplementation.…”