International Omega-3 Learning and Education Consortium for Health and Medicine

Although human and canine fetuses and neonates can desaturate and elongate 18-carbon omega-3 fatty acids (alpha-linolenic acid or ALA) to form their respective longer chain derivatives such as docosahexaenoic acid or DHA (22:6n-3) ^1,2, it is uncertain whether the rate of synthesis is sufficient to meet the demands for optimal growth and development. In a study conducted by our laboratory, we found that, for puppies, the inclusion of modest amounts of DHA from fish oil in the diet during gestation, lactation, and suckling is more effective than high amounts of dietary ALA in improving electroretinographic (ERG) responses at 12-weeks of age ³. The puppies in the fish oil group consistently showed improvement in rod sensitivity (as measured by a-wave amplitudes, response times, and response thresholds) and elicited the largest increase in amplification of the phosphodiesterase cascade necessary for visual function. By comparison, puppies fed a diet rich in the 18 carbon DHA precursor, ALA, had some improvement in rod sensitivity, but it was generally not equivalent to the degree of retinal function evident for the high DHA group. Also, the amount of ALA fed to elicit this lesser response was ten times greater than the amount of DHA fed in the puppies with improved response. Additional analyses of data from the plasma of the puppies revealed that feeding them diets enriched in DHA during gestation, lactation, and after weaning resulted in the accumulation of DHA and was associated with improved neurologic development, as indicated by the ERG response. Thus, a dietary source of preformed DHA appears to be necessary during gestation and suckling for optimal neural development in dogs.

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