The effect of sodium fluoride on egg production, egg quality, and bone strength of caged layers

The development of bone fragility in caged layers is a major problem in the poultry industry. The incidence of bone breakage during the processing of spent hens substantially reduces the economic return from these birds. In two trials, a commercial strain of White Leghorn pullets was used. In each trial, one-day-old chicks were divided into two groups, wing banded, and placed in floor pens. The treated group received fluoridated water at levels up to 300 ppm. The control group of birds received only well water. At 20 weeks of age, birds from each group were transferred to one of two laying batteries. One battery of birds received fluoridated water (100 ppm F). The other served as a control and those birds received only well water. Production rate, egg weight, shell strength, shell thickness, and Haugh units were determined for each bird. At 45 weeks of age, the humeri and tibiae were removed, and bone strength, percentage of bone ash, and fluoride content were determined. Combined data from both trials showed that the fluoride treatment increased the breaking strength of humeri from 6.86 to 13.35 kg and that of tibiae from 6.61 to 13.10 kg. The fluoride treatment also significantly (P less than .01) increased the percentage of bone ash. Egg quality and rate of production were not reduced by the fluoride treatment.