THE BLOWFLY STRIKE PROBLEM OF SHEEP IN NEW SOUTH WALES

A field survey was undertaken between 1972-76 to reappraise the nature of the blowfly problem in New South Wales. For 2 years, 1972-1974, some 80,000 sheep were kept under observation and 12,481 strikes were reported, most due to Lucilia cuprina. Breech strike was still the basic problem but tail strike associated with scouring had become an important component where pastures have been improved. Breech strike was controlled at minimal cost by managerial practices such as docking tails the correct length--second joint-space palpable ventrally (midway down the vulval orifice in ewes) for radically mulesed lambs and the third joint-space (tip of vulva in ewes) for all other lambs-mulesing at lamb marking, mid-season crutching, determining the cause of scouring and applying the appropriate preventative or remedial measures. Thus the use of insecticides could be reserved for the control of body strike in young sheep in the odd wet years and poll strike in horned rams. Major outbreaks of body strike occurred in 1973/74. Body strike worried graziers most because of its unpredictability, sudden onset and scale. and only failing insecticides were available for control.     

OBSERVATIONS OF SW AINSONA GALEGIFOLIA POISONING IN CATTLE IN NORTHERN NEW SOUTH WALES

A mild interstitial pneumonia with mononuclear cell infiltration was produced in calves following intra-tracheal inoculation of the BIL adenovirus. Viral antigen appeared early in the regional lymph node. An interstitial reaction developed early in the lungs, and pneumonic lesions and infective virus were present by the third day after inoculation. Virus spread rapidly to trachea, tonsils and nasal mucosa, and was excreted from the third to eighth day. Upper and lower respiratory tissues continually harboured virus until the 12th day, when the experiment was terminated. The virus was isolated from the livers of two calves. All tissues yielded low concentrations of virus, and only the lung showed pathological reactions. The reactions were qualitatively similar to known adenovirus pneumonias, but considerably milder, and lacked the characteristic necrotic and proliferative bronchiolar changes.