Influence of the method of fluoride administration on toxicity and fluoride concentrations in Japanese quail

Young Japanese quail (Coturnix japonica) were administered NaF for 16 d either in their diet or by esophageal intubation. Based on the total fluoride ion (Σmg F⁻) intake over the 16-d experimental period, fluoride administered by intubation was at least six times more toxic than that fed in the diet. Dietary concentrations of 1,000 ppm F⁻ (Σmg F⁻ for 16 d = approx. 144) produced no mortality, whereas intubated doses produced 73% or greater mortality in all groups administered 54 mg F⁻/kg/d or more (Σmg F⁻ for 16 d ≥ approx. 23 mg). Graphic comparison of the regression of log F⁻ ppm in femurs/mg F⁻ intake showed that fluoride levels in the femurs of quail administered fluoride by intubation were higher than in those administered fluoride in the diet.