Affiliation: | (1) Department of Paediatrics and Child Health, Flinders Medical Centre, The Flinders University of South Australia, Bedford Park, 5042 Adelaide, SA, Australia;(2) Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 12420 Parklawn Dr., Rm. 1-14, 20852 Rockville, Maryland;(3) Child Nutrition Research Centre, Child Health Research Institute, 5000 Adelaide, SA, Australia;(4) Unit of Laboratory Animal Science, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 20852 Rockville, Maryland;(5) Present address: Department of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, 97006 Beaverton, OR |
Abstract: | Previous randomized clinical trials suggest that supplementation of the human infant diet with up to 0.35% DHA may benefit visual development. The aim of the current study was to assess the impact of including arachidonic acid (AA) and a higher level of DHA in the postnatal monkey diet on visual development. Infant rhesus monkeys were fed either a control diet (2.0% α-linolenic acid as the sole n−3 FA) or a supplemented diet (1.0% DHA and 1.0% AA) from birth. Visual evoked potential acuity was measured at 3 mon of age. Rod and cone function were assessed in terms of parameters describing phototransduction. Electroretinogram (ERG) amplitudes and implicit times were recorded over a wide intensity range (−2.2 to 4.0 log scot td-sec) and assessed in terms of intensity response functions. Plasma DHA and AA were significantly increased (P <0.001) in the diet-supplemented monkeys compared with the control monkeys. There was an approximately equal effect of diet for the rod phototransduction parameters, sensitivity, and capacitance but in the opposite directions. Diet-supplemented monkeys had significantly shorter b-wave implicit times at low retinal illuminances (<−0.6 log scot td-sec). There were no significant effects of diet for visual acuity or the other 23 ERG parameters measured. The results suggest that supplementation of the infant monkey diet with 1.0% DHA and 1.0% AA neither harms nor provides substantial benefit to the development of visual acuity or retinal function in the first four postnatal months. This study was conducted at the Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20852. |