Responses of tsetse Glossina morsitans morsitans and Glossina pallidipes (Diptera: Glossinidae) to host-derived phenolic kairomones were investigated using a wind tunnel. Activation behaviour of G. m. morsitans depended on the mixture of the phenols but not on the dose or ratio of the blend used. Up wind orientation behaviour and actual contact with the odour source depended on both the phenolic mixture and on the ratio of the phenols in the blend. In the present studies, a 4:1 blend of 4-cresol and 3-n-propylphenol, respectively, consistently induced more of the flies to fly upwind and contact the odour source as compared to any other combination of the phenols or even when these two crucial phenols were mixed in a ratio of 9:1; the ratio in which they are found in a typical sample of buffalo urine.

Comparison of the responses of the two species indicate that significantly fewer G. m. morsitans fly upwind and contact the odour source on stimulation with a blend of 4-cresol and 3-n-propylphenol as compared to G. pallidipes. This may explain why phenols only produce small improvements in the catches of G. m. morsitans as compared to G. pallidipes.

The simple wind tunnel developed, not only provides a useful tool for rapidly screening candidate attractants, but also a means to investigate how various compounds alone or in various combinations affect tsetse behaviour.

A large number of male and female tenerals and young non-teneral female G. pallidipes were attracted to the exterior of the trap but appeared not to enter the trap readily. About 20% of tenerals of both sexes that visited the trap were captured in the retaining cage and the remaining 80% on the outside. The sex ratio of flies stuck on the outside was 1:1 whereas that of flies from the retaining cage was 1:1.5 females:males. The efficiency of the trap for non-teneral G. pallidipes was about 39%. Direct observation using binoculars from a stationary vehicle about 10–15 m from the trap showed that the catching efficiency of the biconical trap was 30% for a total of the four categories of non-teneral females and males, and teneral females and males.

Adult survival, puparial production, weight and viability, and the sex ratio of adults emerging from puparia of Glossina morsitans morsitans Westwood maintained through four successive reproductive cycles on daily (SO), every other day (SI) and every third day (S2) feeding regimen, respectively were investigated at Chilanga, Zambia. Only in puparial production (0.8 under S0 and S1, 0.7 under S2) and puparial weight (25.1±0.2mg under S0, 24.1±0.3mg under S1, 22.5±0.3mg under S2) were significant differences (P<0.05 and <0.01 respectively) detected between feeding regimens. Nevertheless, a combination of S1 and S2 regimens is recommended for further evaluation as a more convenient and economical alternative to the S0 regimen for tsetse mass production in Africa.

Behavioural-antennal responses of tsetse to buffalo urine, which has been identified as a potent olfactory attractant, were investigated. Tsetse Glossina morsitans morsitans rapidly raised their antennae upon stimulation with the odour of buffalo urine. Flies showed a clear preference for the undiluted urine, though antennal responses even to 100,000 × diluted urine were significantly different from control, indicating the high efficacy of the attracting compounds present in it. Fresh buffalo urine was the most attracting as compared to 4- and 8-day-old urine. The dichloromethane extract of fresh urine was as active as the natural product, indicating that the attracting compounds were extractable into dichloromethane. Under laboratory conditions, responses of males to the urine were significantly more than females.

Chlordimeform (CDM), tested by topical application, was found to be toxic to both male and female tsetse with the maximum effect some 72 hr after treatment. Median lethal doses were approx. 0.4 μg/fly for unfed adult tsetse of both sexes, 100% mortality at 72 hr was achieved with 2 μg/fly. Mature fed females were less susceptible to chlordimeform, the median lethal dose for 72 hr being 12.5 μg/fly. High doses of chlordimeform depressed the weight of puparia from survivors, but had no effect upon fecundity. Sublethal doses caused a significant depression of feeding activity, but did not cause hyperactivity or disrupt fat body lipid reserves.

Four goats, which had been previously bitten on two different occasions by Glossina morsitans centralis infected with Trypanosoma congolense and subsequently treated on each occasion with the trypanocidal drug diminazene aceturate were each fed upon by six uninfected tsetse. Hypersensitivity reactions developed in the skin of two of the goats within 1 hr after the bite, and reached a maximum intensity over the next 24 hr. In order to determine whether hypersensitive skin reactions could be induced by tsetse saliva alone, six different goats were bitten by uninfected tsetse up to eight times. Only a few small nodular skin reactions were noticed. However, following infection and treatment and another sequence of uninfected tsetse bites, hypersensitive skin reactions did occur in two animals, although the reactions were not as severe as anticipated. The hypersensitivity reactions usually precede but sometimes overlap the chancre reaction elicited by metacyclic trypanosomes transmitted by tsetse.

Initial findings are reported from a study of Exhyalanthrax spp. (Diptera, Bombyliidae) and Chrestomutilla spp. (Hymenoptera, Mutillidae) parasitic on tsetse pupae, with a view to their use as control agents. The behaviour of bombyliids in the field and in cages is described and related to problems encountered in laboratory rearing. Limited progress is also reported in the breeding of mutillids. Prospects for the application of pupal parasites in biological and integrated control of tsetse are discussed.

Sounds produced in relation to the sexual behaviour of the tsetse, Glossina m. morsitans, were investigated. During mating, a receptive virgin female adopted a relatively passive role while the male produced sound and drummed her with the tarsi of the meso- and metathoracic legs upto about 4–5 min immediately after mounting. During the long cppulatory phase, the male only produced sound when the female became restless or the pair was disturbed. No sounds were produced during the ejaculatory phase after which the flies separated.

Immediately after separation, the females were often receptive for further short copulations, but were completely unreceptive 24 hr later and showed vigorous repellent behaviour. The post-copulatory behaviour patterns and the rejection behaviour of the female were also accompanied by sound production. Although males readily mated with freshly killed females with the usual mating behaviour, sound production was less intense than when the females were live.

Mating sounds were composed of frequencies up to 50 kHz with the exception of the sounds produced by males, while mating with freshly killed females which not only lacked any ultrasonic components, but were also of low intensity. The most dominant frequency was centered between 1.5 and 2.5 kHz. Peaks were also observed between 0.5 and 0.8 kHz, around 5 and 9 kHz. On the basis of intensity, it is suggested that the frequency components below 10 kHz carry the most important part of the acoustic signal.

The use of indigenous plant materials for the construction of biconical traps to control tsetse is described. Preliminary results from field trials indicated that traps made entirely from local materials performed almost as well as a standard design. It is intended to promote the construction and use of these traps on a community self-help basis in sleeping sickness areas of Uganda.