Background and Aim: Numerous studies have found benefits of omega-3 polyunsaturated fatty acids (PUFAs), namely, for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in dogs. The objective of the present study was to assess the efficacy of dietary inclusion of equal amounts of omega-3 FAs in phospholipid (PL) from krill meal to triglyceride structure from fish oil to increase the omega-3 FA profile in red blood cells (RBCs) in dogs. Materials and Methods: Ten adult Alaskan Huskies of both genders were supplemented with daily 1.7 g EPA and DHA from krill meal for 6 weeks, while another ten dogs received 1.7 g EPA and DHA from fish oil. FA and omega-3 index measurements of the two groups were taken after 0, 3, and 6 weeks for comparison. Results: It was mainly the EPA levels that increased in the krill meal group (from 1.84% to 4.42%) compared to the fish oil group (from 1.90% to 2.46%) (p<0.001), which drove the group differences in the omega-3 index. This resulted in the krill meal group having a mean omega-3 index increase from 3.9 at baseline to 6.3%, which was significantly greater than the increase from 3.9% to 4.7% observed in the fish oil group (p<0.001). Concomitantly, omega-6 PUFAs, such as arachidonic acid and linoleic acid, were reduced in RBC membranes and the omega-6 to omega-3 ratio was significantly more reduced in the krill meal compared to the fish oil group. Conclusion: The results showed that krill meal supplementation was associated with a reduction of omega-6 PUFAs, which compensated for the increased omega-3 index, suggesting that PLs are efficient delivery molecules of omega-3 PUFAs.

Background and Aim: Choline and its metabolites have multiple physiological roles in the body, which are important for muscle function, memory, methylation reactions, and hepatic lipid transport. This study aimed to investigate, if inclusion of phosphatidylcholine (PC) from Antarctic krill (Euphausia superba) can increase the concentration of choline and its metabolites in plasma of sled dogs in comparison to a control group. Materials and Methods: Ten adult Alaskan Huskies of both genders were supplemented with PC from 8% dietary krill meal inclusion for 6 weeks, while another ten dogs received no krill meal supplementation. Blood measurements of the two groups were taken at baseline and end of the study and compared for choline and its metabolite concentrations. Results: The choline concentration of the krill meal-supplemented dogs was significantly higher after 6 weeks of krill meal feeding compared to the control group (mean increase = 4.53 μmol/L in the supplemented versus 1.21 μmol/L in the control group, p=0.014). Furthermore, krill meal-supplemented dogs showed significantly more pronounced increases in betaine (p<0.001), dimethylglycine (p<0.01), trimethylamine-N-oxide (p<0.001), and trimethyllysine (p<0.001) compared to the control group. Significant correlations between changes in choline and changes in its metabolites were observed. Conclusion: The results showed that krill meal supplementation was associated with significantly higher plasma choline concentrations, which correlated with changed concentrations of choline metabolites.