Effects of Fluorine on Dairy Cattle. IV. Milk Production

Abstract

Dairy females consumed 10, 28, 55 and 109ppm of fluoride (F) on a hay basis from about 3 months to 7.5 years of age. The 32 cows were fed also, in a factorially designed trail, 2 levels of concentrate and 2 levels of a Ca-P mineral. Milk production was adversely affected in the 109ppm animals from the 3rd lactation and in some of the 55ppm animals from the 4th lactation. Lactation of animals on the 10 and 28ppm treatments was not affected by treatment. Lactation effects were secondary symptoms of fluorosis. Increased concentrate feeding increased production but had no interrac-tion effects with fluoride treatment. Mineral treatment did not affect lactation. Efficiency in lactation was not affected by F treatment but higher concentrate and 1% mineral cows were more efficient than lower concentrate and 3% mineral cows. Milk residues of F were within safe levels although correlated with F intake.