SHORT-TERM FATE OF HEAVY-METALS TRACE-ELEMENTS, NAPHTHALENE AND POLYCHLORINATED-BIPHENYLS IN LACTATING COWS FED NEWSPAPER

Seven cows were fed a mixture of 0.47kg shredded newspaper, 2.03kg bee tpulp and 2.5kg of molasses daily for 14 consecutive days. Three contr ol animals were fed 5kg of beetpulp daily for the same period. Blood a nd milk samples were taken from all 10 cows on the evening prior to th e start of the experiment and also on the evening of day 14. All milk and blood samples, together with a sample of newspaper, molasses and b eetpulp were analysed for heavy metals/trace elements: Cr, Ni, Cu, Zn, Cd, Pb and Hg; and for 16 polychlorinated biphenyl (PCB) congeners an d the hydrocarbon naphthalene. The heavy metal/trace element levels in both milk and blood samples were within normal ranges. There was no d etectable level of any of the 16 PCB congeners or of naphthalene in an y of the samples analysed. This indicates that newspaper in its presen t form is safe to use as a bedding material for daily cows.