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Sphaerophorus necrophorus is often associated with liver abscesses in cattle. Newsom (1938) isolated S. necrophorus from 96 per cent bovine liver abscesses studied in Colorado; 85 per cent of these contained S. necrophorus in pure culture; 13 per cent contained diphtheroids and staphylococci in addition to S. necrophorus and 3 per cent did not contain viable organisms.Simon and Stovell (1971) isolated S. necrophorus from 97 per cent of liver abscesses studied in British Columbia; in 30 per cent it was in association with other bacteria.Experimental inoculation of viable S. necrophorus into the portal vein of cattle was found by Jensen, Flint and Griner (1954) to produce liver abscesses.There is no previous study of bovine hepatic abscesses in the Sudan despite their high incidence in slaughtered animals (Annual Report, 1969, 1970, 1971. The purpose of this study was to determine the organisms regularly associated with liver abscesses of cattle slaughtered in this country. MATERIALS AND METHODSA hundred bovine liver abscesses representing 100 livers were collected from Omdurman Central Abattoir during 1971 and 1972.Abscesses were opened aseptically and pus material was cultured for S. necrophorus in VL broth which was incubated aerobically at 37~ for 48 hours. In cases with heavy contamination, isolation was achieved by surface culture on ethyl violet-azide agar medium of Barnes and Goldberg (1962) in an atmosphere of 10 per cent CO2 in H2. Purification was sometimes effected by subcutaneous inoculation into rabbits or mice followed by isolation from the resulting abscesses in VL broth.Material from each abscess was also streaked on two blood agar plates and one MacConkey agar plate. One blood agar and the MacConkey agar plates were incubated aerobically at 37~ for 48 hours. The other blood agar plate was incubated anaerobically at 37~ for 48 hours.Organisms were identified by conventional bacteriological procedures. Those identified as S. necrophorus were pleomorphic Gram-negative anaerobes which exhibited biochemical reactions similar to those described in the literature. They produced a turbid growth in VL broth with gas and foul odour and the medium clarified with age. They agglutinated human group O and chicken erythrocytes. RESULTSS. necrophorus was isolated from 84 of 100 bovine liver abscesses; 57 of these isolates were pure cultures and 27 were mixed with coagulase-negative staphylococci or diphtheroids. Of the other 16 abscesses, only coagulase-negative staphylococci were present in six and only diphtheroids in seven and no organism was isolated from the remaining three. 253

In the Sudan, ticks and Tick-borne Diseases (TBDs) with subsequent costs of control and treatment are causing substantial economic loss. Control of ticks is mainly by chemical insecticides. The rising environmental hazards and problem of resistance has motivated research on biological agents as alternative methods of control. The present study aims at controlling livestock ticks using fungi for their unique mode of action besides their ability to adhere to the cuticle, to germinate and penetrate enzymatically. The study was conducted to evaluate the fungus Metarhizium anisopliae for tick control as an alternative mean to chemical acaricides. Pathogenicity of the fungus was tested on different developmental stages of the tick Hyalomma anatolicum. The fungus induced high mortality to flat immature stages. It, also, affected reproductive potential of the females. Egg laid, hatching percent, fertility and moulting percent of immature stages were significantly (p < or = 0.05) reduced. It was, also, shown that the fungus had ability to adhere to the cuticle and penetrate the integument of the tick. Conidia of the fungus were isolated from their internal tissues. This phenomenon is important in considering fungi as bioinsecticides. Infection of eggs laid by treated engorged female ticks, with the fungus might demonstrate suggesting transovarian transmission. The use of M. anisopliae to control ticks is discussed.