The effect of water-borne fluoride on the egg production of laying hens

One thousand Silver Grey Hyline hens were given drinking water containing 6 , 10, 14 and 20 mg/l sodium fluoride during their laying period. The contro l group received municipal water (containing 0.29 mg/l fluoride) with no ad ded sodium fluoride (0 mg/l). Fluoride addition to the water had a significant effect (P = 0.0001) on egg production, but eggshell breaking strength was not significantly influence d. At the termination of the study (74 weeks of age) the carcass mass and the fluoride content of the os femur showed a significant increase (P = 0.0001) which correlated with the increase in fluoride concentration in the water. No important microscopic changes in the livers and kidneys were noticed, an d liver mass and breaking strength of the os femur, were unaffected by the amount of fluoride consumed. The data showed a significant drop in egg production at 6 and 20 mg/l sodiu m fluoride.