POSSIBLE DIP FACTOR

Press, Volume C, Issue 29513, 13 May 1961, Page 7

POSSIBLE DIP FACTOR

In his thesis on “Some aspects of the ecology and physiology of bacteria and fungi in the fleece,” which has earned him a doctorate in philosophy in agricultural mircrobiology. Dr. A. P. Mulcock says that the fungus Peyronellaea glomerata. which causes a black discolouration of the tips of the fibres, has been found to be widespread throughout New Zealand. It therefore seems strange that complaints had not been received about it prior to one from Japan in 1958. One explanation, he says, is that the incidence of the fungus has increased over the past few years. “Before about 1945 sheep were dipped with either arsenical or carbolic dips,” he says, “but since that time DDT, benzine hexachloride, aldrin, dieldrin and diazinon dips have been introduced and to a great extent have replaced the older types. ‘None of these compounds is particularly active against micro-organisms and, as a result of costly experience, all dip manufacturers now add bacteriostatic ingredients to their dips. Experiments have shown that the fungus is not inhibited on agar media containing some common dips now in use. but is strongly inhibited by the old type carbolic dips, but whether the residual effects of carbolic dips would be sufficient to protect the fleece from infection is a problem which is worthy of further investigation.” 1