DR  RAJINDAR  SAINI  ICIPE  (AFRICAN  INSECT  SCIENCE  FOR  FOOD  AND  

HEALTH)  

Novel tsetse repellent technology for enhanced livestock

productivity and food security in Africa

Tsetse Repellent Technology

R. K. Saini

Amongst the 42 poorest countries in the world, 32 are African and host tsetse - vectors of

trypanosomes

Spread over 7 million km2

Threatening 60 million cows 230 million sheep 40 million goats with

trypanosomosis

Leading to death of 3 million cattle every year Loss of 500 000 tonnes of meat and 1 million tonnes of milk.

Reduction to 10% animal draught power and to 50% livestock production

Costs $ 40 million annually on drugs 4.5 billion US$ a year for the

African economy

African Animal Trypanosomiasis (AAT)

Vectors of Human Sleeping Sickness

G. f. fuscipes

•  70 million people are at risk of getting human sleeping sickness ( HAT)

•  10,000 more people infected yearly

•  95% of infected persons are not treated

•  palpalis group of tsetse in West Africa •  Savannah species (morsitans group) in Eastern and Southern Africa

Sleeping sickness patients (Angola) pic. courtesy WHO

resulted in 2 major discoveries:

- Development of the NGU series of traps (NG2B, NG2G) which are cheap and easy to

make

- Identification of odour attractants to enhance visual appeal of the traps – Buffalo and cow

urine shown to be potent attractant for G. pallidipes 4-cresol and 3-n-propyl phenol

identified as attractive compounds

Host Seeking Behaviour

Repellents for tsetse control

Pastoralists need mobile technology suited to their lifestyle

Why Repellents?

Tsetse Repellent work at icipe

Identification of Repellents

Synthetic sources

Natural blends of un-preferred animals (waterbuck, zebra)

Tsetse - synthetic repellent (SR)

•  A synthetic Repellent (SR) 2methoxy-4- methylphenol (patent No: KE00185) identified by molecular optimisation studies, wind tunnel and field assays

•  Prototype dispenser with a constant release rate that individual cow wears designed

•  Initial field tests with SR showed a reduction in disease incidence among cattle from 40% in Masai Mara to 70% in Coastal areas of Kenya

•  Drug use significantly reduced

Challenges

•  Loss and leakage of dispensers (85%)

•  Mixing of herds

•  Waterbuck are present in tsetse habitats but not fed upon

•  Refractoriness is mediated by repellents

•  15 EAD active compounds were found in the waterbuck odour •  Through series of field experiments 5 - component blend was identified (icipe patent application)

•  WRB reduces fly catches by 80% and feeding efficiency >95%

Cows in waterbuck clothing

Tsetse – identification of repellents from un-preferred hosts

Gas chromatogram of body odors from waterbuck

Repellency attained with new dispensers model is comparable with icipe prototype dispensers Release rates: SR: 9.00 + 0.5mg hr-1 WRB: 10.5 + 0.5mg hr-1

Dispensing of Repellents

Validation trials in Shimba Hills

Objective: Integration of repellents with other tsetse control tactics – evaluation of ‘push-pull’

Large scale repellent technology validation trials in ‘push’ mode or in ‘push-pull’ mode were undertaken at Shimba Hills, Kenya Coast

Map of trial sites in Kwale District

Shimba Hills Game Reserve

•  600km2

•  260 farmers • 1528 animals

Effect of repellents on disease levels

Disease incidence in herds protected with WRB

b

c

d

a

% disease reduction with WRB

Disease reduction with WRB 86%

aa

bb

Mean monthly body weight in cattle with WRB

Weight of cattle protected with WRB treatments was significantly more than those in control or in areas with traps (pull) No difference between traps and control. Weight gain translates into more money

a a

bb

Farmers assessment of repellent collars

Treatments % of HH aware of collars technology

Rating for effective and very effective

Push pull WRB 100 100

Push pull SR 100 100

Push WRB 100 96.6

Push SR 97.8 91.1

Pull 80.0 100

Control 75.6 94.1

NPF 81.6 100

•  97% farmers report that the technology is very effective in protecting their cattle

Impact on grazing

Livestock farmers are reporting: •  95% can graze their animals anywhere including in tsetse infested areas. Animals are now more settled when grazing or ploughing •  Farmers have stopped lighting fires to smoke away the flies in the evenings •  45% farmers without collars prefer to graze their animals with protected animals

Impact on ploughing

•  Protected animals plough 75% more land •  Average area ploughed increased by 3.2 acres per household with protected animals •  Number of farmers hiring oxen for ploughing land reduced by 62% •  Food Security enhanced & livelihoods improved

•  Number of households reporting lactating animals in the herd has increased by 67% (103 to 172)

•  The number of animals lactating is 2x more in protected animals compared to control •  The average milk production per animal is 42.2% higher in the protected animals compared to the control •  cows are native

Impact on milk production

•  99.5% of the respondents in all the treatments, control and non participating farmers are willing to buy the repellent collars

•  On average, farmers willing to pay Kshs. 212/= (US $ 2.5) for collars

•  Farmers wish the repellent dispenser would last 4.8 months on average

•  67% farmers willing to change breed of animals if collars are available

Potential for Adoption

% dispensers working in cattle herds with WRB treatments

Dispensers - problems

About 75% dispensers are working at any given time

Cost of dispenser and repellent compounds per month Dispensers: $1.50 Repellent compounds: $2.75 Belt: $0.08 Total costs: $4.33 (lab. Costs)

Cost of drugs (chemotherapy) 2 treatments per month : $ 2.35 (mass produced)

Costs of technology

Way Forward

Tabanid fly Stomoxys calcitrans

camel trypanosomaisis (surra)

•  Roll out novel tsetse repellent technology in African countries •  Ensure manufacturing scale-up of the technology through public-private- partnerships (non- metallic, robust, low cost dispensers through p-p-p) •  Integrated use of the repellent technology with other tsetse and disease control tactics to eliminate the constraint of tsetse and trypanosomiasis (T&T) in African countries

•  Evaluate potential to control vectors of human sleeping sickness. •  Evaluate repellents to protect safari vans and tourists from tsetse attack in parks

•  Develop repellent collars for camels and their integration with other vector control tactics

Acknowledgements

Mathews Bett PhD student (Moi University)

Spala Ohaga PhD student (Jomo Kenyatta

University)

Hippolyte Affognon (PDF)icipe

Norber Mbahin (PDF)

John Andoke

Peter Musa

David Mbuvi Mbesi

John Otieno Ngiela

Tiberius Marete

Phillip Kolei

Lemorora Nkoyokoi

Caroline Muya

Abel Orone KARI-TRC

Gabriel Karanja KARI-TRC

Abdalla Mwachongwa Vet. Services

KIRDI

Thanks to EU for funding the research