N-3 fatty acid deficiency induced by a modified artificial rearing method leads to poorer performance in spatial learning tasks

Pediatr Res. 2005 Oct;58(4):741-8. doi: 10.1203/01.PDR.0000180547.46725.CC.

Abstract

Docosahexaenoic acid (DHA) is a major structural component of the nervous system, and depletion may lead to losses in neural function. Our objective was to demonstrate a deficit in spatial task performance in rats with low brain DHA due to a low n-3 fatty acid intake using a first-generational artificial rearing technique. Newborn rat pups were separated on d 2 and assigned to two artificial rearing groups or a dam-reared control group. Pups were hand fed artificial milk via custom-designed nursing bottles containing either 0.02% (n-3 Def) or 3.1% (n-3 Adq) of total fatty acids as LNA. At d 21, rats were weaned to either n-3 Def or n-3 Adq pelleted diets and several behavioral tasks were evaluated at 9 wk of age. Brain DHA was lower (58% and 61%, p < 0.001) in n-3 Def in comparison to n-3 Adq and dam-reared rats, respectively. At adulthood, the n-3 fatty acid-deficient rats had a significantly greater moving time than the dam-reared group (p < 0.05), but there were no differences among the three groups in the elevated plus maze test. The n-3 fatty acid deficient rats exhibited a longer escape latency (p < 0.05) and poorer memory retention in the Morris water maze compared with n-3 fatty acid adequate and dam-reared rats. We concluded that artificial rearing can be used to produce n-3 fatty acid deficiency in the first generation. This deficiency was associated with significantly reduced spatial learning. Adequate brain DHA levels are required for optimal spatial learning.

MeSH terms

  • Animal Nutritional Physiological Phenomena
  • Animals
  • Animals, Newborn
  • Arachidonic Acid / metabolism
  • Body Weight
  • Brain / metabolism
  • Docosahexaenoic Acids / metabolism
  • Fatty Acids, Omega-3 / metabolism*
  • Fatty Acids, Omega-3 / pharmacology
  • Female
  • Learning*
  • Lipids / chemistry
  • Maze Learning
  • Memory*
  • Rats
  • Rats, Long-Evans
  • Spatial Behavior*
  • Time Factors

Substances

  • Fatty Acids, Omega-3
  • Lipids
  • Docosahexaenoic Acids
  • Arachidonic Acid