Host-location behaviour TseTse Flashcards
Why is understanding host location important?
-timing of host seeking
-host selection
-host-oriented behaviour
-host stimuli
-host-vector interactions
for
-risk factors
-control methods
-vector monitoring
Describe gambiense
-Chronic in humans
-90% of cases
-Human+ animal reservoirs
Transmitted by palpalis group (riverine)
Describe rhodesiense
- Acute in humans
- 10% of cases
- Animal+ human reservoirs
- Transmitted by morsitans ( savannah)
What do T brucei have in common
- No vaccine
- No prophylactic drugs
- Ultimately fatal for humans
- Asymptomatic in animal reservoirs
What is tryptanomyiasis in cows called and why is it bad?
Nagana - less milk and meat -lower reproductive capacity -less draught power -more susceptable to disease increased mortality
what causes nagana
T. vivax, T. conglense
Where can you find Glossina flys?
Restricted to central africa, too hot and dry in sahara, too cold in south africa
What is the most important group of vectors for gambian SS in central and west africa. give a few EGs
Palpalis group, G. palpalis palpalis -west africa G. palpalis gambiensis G. tachinoides G. fuscipes fuscipes- central africa G. fuscipes quanzensis
How many tsetse do you have to kill per day to eliminate a population?
about 3%/day
which sex blood feeds? and what for
Male and female, growth and reproduction
How do tsetse find their host?
sit and wait for animal to come to them or
go out and find it
Describe an experiment to test exogenous stimuli
Artificial refuge, with specific stimuli, monitor
When are savannah tsetses active
diurnally active with bimodial peaks in activity
What sense to savannah testse use and riverine?
savannah- 90% olfactory
riverine- use vision more
How do you test whether a fly uses olfactory or visual cues?
Compare the number of tsetse attracted to a host with or without an odour
What bodypart do tsetse use to pick up host odours?
antennae
How would you identify attractants?
Electro antennaegram- gas chromatography- mass spec
What natural host odours attract tsetse?
Carbon dioxide acetone 1-octen-3-ol 4-methylphenol 3-n-propylphenol
How effective is an artificial attractant?
A blend of four of the attractants ( cant use CO2 for practical reasons) dispensed at 10X the dose attracts as many tsetse as a cow
What do tsetse use at close range
Visual cues at
How would you test if a tsetse uses olfactory or visual cues
multiple targets and host odour
In descending order what colours are tsetse most attracted to?
blue,red,white,green,yellow
Do tsetse have colour vision?
yes
In descending order what shape do tsetse like the best
horizontal oblong, square, vertical oblong
How can you eliminate a population of tsetse in a year?
Odour baited targets, treated with insecticide and deployed at densities of 4/km2
Describe a good trap for a savannah tsetse
-big, blue,black,horizontal oblong, odour baited
Higher or lower density for riverine tsetse?
Higher density because cant use odour as well
whats a good trap for riverine tse tse?
small to reduce material cost, netting on outside to catch outflanking fleeting flies,square,blue,no attractants
