Abstract:To assess the neurobehavior and cognitive ability of rat offspring exposed to yttrium nitrate.Methods Pregnant rats were orally exposed to yttrium nitrate by garage at 0,5, 15 or 45 mg/kg BW dose from gestation day (GD) 6 to postnatal day (PND) 21, then offspring were given the same dose until PND 63. The indexes of body weights, food consumption, organ weights and neurobehavior test results such as hot plate, motor activity and Morris water maze test were recorded. Results All yttrium-exposed male offspring showed a significantly increased body weight on PND 21. However, male offspring body weight of 45 mg/kg BW dose decreased significantly from PND 42 to the end of the experiment (P<0.05), which caused a lower weight change and overall food consumption (P<0.05), but all groups showed similar feed conversion ratios. The differences on other body weight and relative brain weight between treated and control groups were not considered treatment-related. The only significant difference in Morris water maze test was the high dose female offspring which showed a higher latency on the fifth day (P<0.05), and similar results were observed among other neurobehavior tests.Conclusion Continual exposure of yttrium nitrate could cause a decline in the body weight of high dose male offspring, but would not affect the brain weight. Moreover, no differences were found in tests of hot plate, motor activity and Morris water maze test.