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.

Keywords: choline metabolites, choline, dog, krill meal, phosphatidylcholine.

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