Long-Chain (n-3) Polyunsaturated Fatty Acids Are More Efficient than α-Linolenic Acid in Improving Electroretinogram Responses of Puppies Exposed during Gestation, Lactation, and Weaning

Abstract

Long-chain PUFAs (LCPUFAs) are essential for proper neural and retinal development in many mammalian species. We investigated puppies born to dogs fed diets containing varying amounts of vegetable and marine (n-3) fatty acids during gestation/lactation. The fatty acid compositions of dogs' milk and puppy plasma phospholipids were evaluated, and electroretinographic responses of the young dogs were determined after they were weaned to the same diets. Dogs' milk fatty acid composition reflected the diets fed during gestation/lactation. The milk of dogs fed a high alpha-linolenic acid (ALA) diet was enriched in ALA but not docosahexaenoic acid (DHA). Puppies fed this ALA-enriched milk accumulated more plasma phospholipid DHA than the low (n-3) fatty acid group. However, this accumulation was less than that obtained in puppies fed preformed DHA during development and suckling (P < 0.05). Electroretinograms (ERGs) of 12-wk-old puppies revealed significantly improved visual performance in dogs fed the highest amounts of (n-3) LCPUFAs (P < 0.05). These puppies demonstrated improved rod response (improved amplitude and implicit time of the a-wave, P < 0.05). Puppies from the low (n-3) fatty acid group exhibited the poorest ERG responses compared with the high-marine or high-vegetable (n-3) groups. A novel parameter devised in this study, the initial intensity at which the a-wave was detectable (i.e., threshold intensity), also demonstrated that retinal response of puppies consuming the (n-3) LCPUFA-containing diets occurred at lower light intensity, thereby exhibiting greater rod sensitivity, than the other diet groups. These findings indicate that preformed dietary (n-3) LCPUFA is more effective than ALA in enriching plasma DHA during perinatal development and results in improved visual performance in developing dogs.

Early and Sustained Enrichment of Serum n‐3 Long Chain Polyunsaturated Fatty Acids in Dogs Fed a Flaxseed Supplemented Diet

“…Similar enrichments of EPA and DPAn-3 have been observed in human plasma using a 4 week feeding period [24]. For that matter, this phenomenon has been observed in humans and various other animal species (reviewed in [25]) and is consistent with other evidence that plasma enrichment of DHA after ALA supplementation is less efficacious than providing smaller dietary amounts of preformed DHA per se [25,26]. It should be noted that studies in rats have shown the conversion of ALA all the way to DHA to be effective in liver and plasma [27].…”

Comparison of the nutrient composition of commercial dog milk replacers with that of dog milk

“…Supplementation of female dogs with ALA during gestation and lactation does not result in increased amounts of DHA in canine milk. 33,34 …”

“…Although most of the milk replacers contained similar or higher ALA concentrations, compared with dog milk, ALA supplementation of both gestating dogs and growing puppies does not have equivalent benefits to supplementing with DHA directly when it comes to retinal function; therefore, having similar concentrations of ALA in milk replacers, compared with dog milk, may be of little value, compared with similar concentrations of EPA and DHA. 34 More data are needed, but current research suggests that puppies may benefit from supplementation of DHA (but not necessarily ALA) to at least the concentrations found in the milk of domestic dogs consuming diets lower in total n-3 fatty acids.…”

Sea Buckthorn, Dry Eye, and Vision

“…They regulate several functions of the body, including inflammation, 25 which, according to current knowledge, is involved in the development of disorders affecting vision. 37 Sea buckthorn seed and pulp oils are rich sources of tocopherols and tocotrienols (Table 48.1). 30 Oral intake of combined linoleic and γ-linolenic (18:3n-6) acids has been shown to relieve dry eye.…”