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Abstract

The aim of this study was to investigate the possible impact of fluoride emissions
from an aluminium smelter on beef cattle on a nearby property. However, it was not
possible to successfully achieve this aim. Instead, all mechanisms of fluoride uptake
on the farms studied, including emissions from the smelter, were examined in
relation to the condition of cattle on the properties.
Ambient air monitoring demonstrated that fluorides, both gaseous and particulate,
were generally low at all stations on the study property. The Washington State
Standards were exceeded at two of the three monitoring stations early in the
monitoring program but were below detection level for much of the later period of
the study. Elevated levels of gaseous and particulate fluoride recorded at individual
stations did not necessarily correlate.
Pasture fluoride was the major source of fluoride for stock and levels varied over a
wide range. Many of the very elevated pasture fluoride levels were associated with
periods of fertilizer application. Normal fertilizer application practices on the control
farm, remote from the smelter, elevated pasture fluoride levels sufficiently for the
Washington State Fluoride in Forage Standard to be exceeded. The main study property
was marked by low pasture availability, poor pasture cover and heavy grazing for
much of the study period. Water was not a significant source of fluoride for the stock.
Bone fluoride levels of the cattle on the study farm were elevated relative to those on
the control farm. The rate of increase of these levels tended to decrease with age and
appeared to be influenced by specific farm management practices. Many of the cattle
on the study farm showed tooth damage and loss. This damage was more excessive
than would have been expected, given the bone fluoride levels, and indicates that the
cattle have been exposed to variable levels of fluoride. Bone fluoride levels and the
development of teeth defects have been complicated by agistment of some stock
during the period critical for the development of the first permanent teeth. They have
also been complicated by other factors including the variations in feed availability
across the property and the variability of exposure to fertilizer.
Fertilizer application was found to affect both the teeth condition and bone fluoride
levels of exposed cattle. A 30% reduction in smelter output during the course of the
study did not significantly reduce the rate of increase of the bone fluoride levels in
young cattle. Trace element supplementation of calves, distributed over a number of
farms, did not produce the same levels of weight gain over all properties, reflecting
apparent variations in trace element availability on the farms.
Farm management practices, in particular high stocking rates and heavy grazing
combined with poor pasture cover, resulted in reduced feed intake and poor
condition of the cattle. Low pregnancy rates in some cattle were a result of their poor
condition, not fluoride intake. Removal of these cattle to properties with better
grazing conditions resulted in remarkable improvements in condition and improved
pregnancy rates.

Item Type:	Thesis - PhD
Authors/Creators:	Pollington, Michael J.(Michael John)
Keywords:	Fluorides, Beef cattle, Beef cattle, Beef industry
Copyright Holders:	The Author
Copyright Information:	Copyright 1997 the author - The University is continuing to endeavour to trace the copyright owner(s) and in the meantime this item has been reproduced here in good faith. We would be pleased to hear from the copyright owner(s).
Additional Information:	This thesis investigates the possible impact of fluoride emissions from an aluminium smelter on the productivity of a nearby beef cattle (black Angus) breeding property in northern Tasmania, in response to concerns by local farmers. All possible mechanisms of fluoride uptake on the farms studied, including emissions from the smelter, were examined in relation to the condition of cattle on the properties. Thesis (Ph.D.)--University of Tasmania, 1998. Includes bibliographical references. This thesis investigates the possible impact of fluoride emissions from an aluminium smelter on the productivity of a nearby beef cattle (black Angus) breeding property in northern Tasmania, in response to concerns by local farmers. All possible mechanisms of fluoride uptake on the farms studied, including emissions from the smelter, were examined in relation to the condition of cattle on the properties
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