On the fifth day after the application of the ticks, the bandicoots were transferred to the col- lecting cages used with the nymphs (Figure 2) and given reduced rations. The trays were inspected every three hours during the day and cleaned and relined with fresh absorbent paper when necessary. The majority of the ticks detached bet- ween the days 6-8 after attachment. The yield of engorged ticks varied between 40 and 70%, the lower yield was due mainly to the ability of ban- dicoots to scratch them out. To reduce the chances of this happening the bandicoot’s long claws were kept trimmed. Bandicoots were allowed to recover for 2 weeks before ticks were reapplied.

The replete ticks, which were blue-grey, were washed in distilled water and placed in 15cm covered petri dishes, the floors of which were covered with several circles of filter paper. A 5cm by lcm (id) length of PVC tube filled with moist cotton wool was placed in each dish to maintain a high humidity. The lids of the petri dishes were half covered over with black photographic paper to enable the ticks to select their own light re- quirements. Every 2 days the healthy ticks were transferred to clean dishes and after approxi- mately 10 days, when the ticks had changed to a grey colour, they were transferred onto moist sand, 3 ticks per jar. Egg-laying commenced about 2 weeks after engorgement and continued for a further 2 to 3 weeks. On completion, the females were removed from the jars and the eggs kept on the damp sand at 20-25°C. Three to 5 months elapsed before larvae emerged.

Discussion

1. holocyclus produces a toxin in the salivary secretion capable of killing its host - one female can kill a dog. Furthermore, it is catholic in its choice of mammalian host and readily attacks man who frequently becomes hypersensitised to

the bites of larvae, consequently great care has to be taken in the management of a colony.

The techniques described were used to maintain successfully for 3 years a colony capable of pro- ducing 3000 female 1. holocyclus annually. To achieve this level of production 100-150 females were retained for egg production, from which about 80,000 larvae were obtained, of which 50,000 engorged to produce 25,000 nymphs. The life cycle under the laboratory conditions occupied 7-9 months.

Guinea-pigs were used to feed larvae because of their availability, convenient size and ease of handling. However, several nymphs or a single female killed the guinea-pig before the ticks were fu l ly fed, so immune bandicoots were required to feed these instars. Larvae were only applied to guinea-pigs once because of the rapid onset of an immune response which prevents completion of feeding (Bagnall 1975). Nymphs and adults could be applied to bandicoots with a previous experience of tick feeding several times before an appreciable loss in numbers was encountered. A source of replenishment of both hosts was thus re- quired, the reserve of 40-50 bandicoots being the most difficult to maintain.

The facilities required were considerable, and the operation was labour-intensive, even the technician employed to maintain the colony required assistance at critical times. However, all instars were available throughout the whole year.

Acknowledgments We wish to thank L . Stacey, C. Reece, R. Townsend and

Mrs J . Edwards for their technical assistance.

References Bagnall, B. G. (1975) - C u t a n e o u s Immunity to the Tick

Oxer, D. T. and Ricardo. C. I-. (1942) - Aust. vet. J . 18: 194. lxodes holocyclus. PhD. Thesis, Uni. Sydney, Sydney.

(Accepted for publication 17April1978)

BOOK REVIEW: The 1 a71 (;real I’lagiic. Coi1linut.d f ro i r i psgc 468

w i l l find out how to lame thih versatile virus; the story of discobery is not yet finished’.

Under ‘Milestones’ is a chronology of events from 1931, w h c n inf luenza virus was isolated f r o m swine. to tlie stcine influenza outbreah at Fort Dix i n 1976, and there is a usef‘ul glossary.

This fascinating little book will interest everyone - most of us habe had influenza and the spectre of the 1918-19 pandemic slill looms - and, while our knowledge of tlie epidcmiology

.A~r.srra/rari \.ererrriar~,./our/fa/. Vol. 54, October . 1978

and control of viral diseases grows each year, we cannot be certain precisely how a n epidemic or pandemic wil l behave. Moreover, as we change the sociological and husbandry backgrounds for man and his animals we must, inevitably, also change the background for the behaviour of their diseases. In his section on ‘Questions Seldom Asked’, but wshich he poses, the author includes both warning and stimulus. We may have tlic means to seek answers, but will we d o so?

H . McL. Gordon

493