Kinetics of docosahexaenoic acid ethyl ester accumulation in dog plasma and brain

•Concentrated DHA Ethyl Ester (DHA-EE) was administered to beagle dogs at doses up to 2000 mg/kg bw/day by oral gavage in this 9-month study.•DHA-EE was well tolerated; occasional reddened areas and dry flaky skin were observed at doses ≥1000 mg/kg bw/day in both sexes.•DHA-EE administration resulted in DHA increases in the brain and plasma.•Plasma dog levels reached a steady state at the dose of 1000 mg/kg bw/day.•To maximize dog brain levels of DHA, 150 mg/kg bw/day is sufficient if DHA is administered chronically.

This study explores dog plasma and brain fatty acid composition achieved after long-term supplementation at high DHA doses. A 90% concentrate of DHA Ethyl Ester (DHA-EE) administered by oral gavage to Beagle dogs at doses of 100, 500, 1000, and 2000 mg/kg bw/day for 8 weeks resulted in DHA increases in both plasma and brain. In a subsequent 9-month study, DHA-EE was administered at 150, 1000 and 2000 mg/kg bw/day. Plasma DHA increased between 150 and 1000 mg/kg bw/day but not between 1000 and 2000 mg/kg bw/day and there were increases from Day 1to 92 but not between days 92 and 273. Doses >500 mg/kg bw/day in the 8-week and all doses in the 9-month study resulted in DHA increases in the brain. The dose of 150 mg/k gbw/day is sufficient to achieve maximal brain concentrations if DHA is administered chronically. For shorter than 6 months of supplementation, higher doses are required.