Comparative role of vitamin A and β-carotene on reproduction and neonate survival in rats

Abstract

Female rats were used to investigate the comparative role of vitamin A and β-carotene (dietary or injected) on growth, feed intake and reproduction. After 3 wk of vitamin A and β-carotene depletion, rats were assigned to one of six groups: 1) CON = fed 5% NRC recommended level of vitamin A (= 60 μg retinol equivalent (RE)/kg diet); 2) VA = fed 100% of vitamin A (= 1200 μg RE/kg diet); 3) HVA = fed 150% of vitamin A; 4) VA+C = fed 100% of vitamin A + 1.2mg β-carotene; 5) VA+IC = fed 100% of vitamin A + injected weekly with 8.37 mg of β-carotene; and 6) VA+IVA = fed 100% of vitamin A + injected weekly with 1400 IU of vitamin A. The level of vitamin A and β-carotene in dam blood and liver reflected the level of supplementation. No difference in feed intake or body weight was observed. Although mean litter size was similar for all groups, mean pup weight at birth was lowest for deficient rats. Pup mortality through 2 wk postpartum was lower for groups receiving higher levels of either vitamin A or β-carotene. However, supplemental β-carotene did not influence growth or reproductive performance. Therefore, low intakes in vitamin A or β-carotene had no effect on feed intake, growth or reproduction in female rats but decreased fetal growth and increased mortality among pups.