Description of a research initiative proposed by France and Upper Volta to explore means of approaching trypanosomiasis through tsetse fly control (release of sterile males) and analysis of trypanotolerance in N'dama, Baoules, and Laguna cattle. Projected five year costs of implementing the program. Agenda item presented at TAC Sixth Meeting, July - August 1973

Institut d'Elevage et de Médecine Vétérinaire des Pays Tropicaux

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DDDR:IAR/73/17 RESTRICTED May 1973 COHSULTATIVEGROUP ON INTERXATIONAL AGRICULTURAL RESEARCH TECHNICAL ADVISORY COMMITTEE Sixth Meeting, Washington, D.C., 25 July-3 AuGst 1973 RESEARCH PROGRAMME CONCWING TRYPANOSOMIASES PND THEIR VECTORS (Presented by the Government of France) (Agenda Item 11) TAC SECRETARIAT FOOD AND AGRICULTURE ORGAXIZATICX OF THE UNITED r\rd'!IOr;rS ROME 1373 =/I)9179 RESEARCH PROGRAMME CONCERNING TRYPANOSOMIASES AND THEIR VECTORS (Presented by the Government of l?rance) Trypanosomiases are due to the multiplication of mono-cellular parasites, trypanosomes, in the blood of man and hot-blooded animals, and which are necessarily transmitted through insects : glossina or tsetse flies. The prevention of those diseases takes place either by eliminating the tsetse flies which ensure propagation, or applying curative or prevent- ive treatment with chemical drugs to sick animals or those liable to be infested by trypanosomiases. There is not yet any biological method similar to those employed against bacterial or virus diseases (vaccination, prevention) as the immu- nological bases of trypanosomiases remain to be discovered. It is however a well-known fact that certain breeds of Bos taurus taurus - N'dama, Baoules, Laguna breed , can live and multiply normally in zones of endemism of tsetse flies infested with trypanosomes (Ivory Coast, Ghana). Laboratory analyses indicate that animals of these breeds showing an appearance of good health may harbour trypanosomes. The mechanism of this "trypanotolerance" remains to be elucidated and if it were so, it would certainly be possible to develop effective biological methods of ,protecting the livestock against trypanosomiases. -2- The programme described below studies the two fields of disease and vector control which seem to be the most promising to French Researchers. CONTROL OF TSETSE FLIES The tests of chemical control of tsetse flies performed on a large scale have shown the difficulties and limits of action through insecticides. It appeared that this method could be favourably completed by the biological prevention which,should enable to finish off the control opera- tions and result in real eradication. Two methods can be considered : - to release sterile male tsetse flies - chrysalis parasites. The first method has been the subject of important preliminary studies concerning the breeding of tsetse flies and their sterilization. The second one has for the time being , only been the subject of limited studies. Aelease of sterile males This method makes use of a physiological peculiarity of tsetse flies : with those insects, the entire offspring of a female originates from ovules which are fecundated by the sperm of the first male with whom she mated. Therefore , if the sperm of this first male contains no spkrma- tozoon or abnormal spermatozoa, the female will have no offspri,ng. The programme which is presently starting up at Bobo-Dioulasso, Upper Volta, will cover forest living glossina species which appear to be the most vulnerable. -3- The.breeding unit will contain 30,000 female tsetse flies producing from 18 to 20,000 males per month. The breeding technique will be that developed by the Institute for Tropical Countries Breeding and Veterinary Medicine at Maisons-Alfort. Sterilization of males will be obtained through irradiation with Cesium 137. The pilot programme which will take place in a ranch located at approx. twenty miles from Bobo-Dioulasso, will include four tests : I- insecticide treatment of the resting places of tsetse flies with an insecticide having relatively short remanence, then one year later, release of sterilized males. II - release of sterilized males, without prior treatment. III - treated check zone : Insecticide treatment of the resting places of tsetse flies with an insecticide having long remanence. IV - non-treated check zone. Studies of chrysalis parasites This programme will be inserted into the preceding one and will consist in : - studying all the pathological phenomena (microbial or parasitic) which may appear in the breeding unit , in view of their possible use in the biological action; - more special study of Thyridanthrax. -4- STUDY OF THE PHENOMENON OF TRYPANOTOLERANCE It is almost certain that the phenomenon of trypanotolerance has a genetic basis; African bos taurus appears to possess it to a high degree. Ranch tests in zones infested with tsetse flies, especially in the Ivory Coast, have shown that the breeding of this bos taurus is perhaps an effect- ive means of developing breeding in a damp tropical zone. The Bobo-Dioulasso centre is well located to develop research on trypanotolerance. As a matter of fact , its ranch and its geographical po- sition enable it to have large herds of sensitive bos indicus taurus and trypanotolerant bos taurus taurus. Moreover, the laboratory now being built will enable it to make natural spreadings of the disease with the bred tsetse flies. Research will cover the immunity reactions of the various bovine stocks infected naturally with stocks of T. vivax, T. congolense, whose antigenic structure will have been defined. Research will aim at discovering the correlations existing between trypanotolerance and the genetic, biochemical, and biological characteris- tics of the animals which possess it. Material results can be achieved in five years in the field of the biological action against tsetse flies. The results in the field of research on trypanotolerance will be less rapidly achieved, especially in the field of genetics, as four years are required per generation of horn cattle. -5- IMPLEMENTATION OF THE PROGRAMME The French Government has already planned to grant a credit of 5 million francs, i.e. 1 million dollars, to the Institute for Tropical Countries Breeding and Veterinary Medicine, in order to finance the re- search performed in the field of biological action against tsetse flies over the next five years. The Government of Upper Volta has granted to the Institute for Tropical Countries Breeding and Veterinary Medicine the full ownership of a site at Bobo-Dioulasso on which the laboratory is now being built, and has placed at its permanent disposal a 7,400 acre ranch. Furthermore, it has acknowledged international status for the Institute for Tropical Countries Breeding and Veterinary Medicine which is an independant establishment, and granted it both fiscal and customs exemptions. Thus the conditions for forming an international team of resear- chers are fulfilled. The cost of the programme as a whole, for the next five years, is estimated at F.F. 13,900,000, i.e. US $ 2,78C,OOO, F.F. 5,OQO,OOO or US $ 1,000,000, of which for the "'Biological action against tsetse flies" programme, and F.F. 8,900,000, or US f 1,780,000, for the programme con- . cerning trypanotolerance. -6- ESTIMATE for 5 years I- BIOLOGICAL ACTION AGAINST TSETSE FLIES STAFF F.F. us $ - Expatriate : 2 entomologists whereof 1 programme manager 3 laboratory technicians . . . . . . . ..‘L....... 1,270,OOO 254,000 1,194,ooo 238,800 - African : I secretary, 1 driver, 2 laboratory aids, 17 workers, 30 labourers, for the pilot breeding station ..,....O................ 430,000 86,000 INVESTMENTS - Technical building ............................. - Housing ........................................ - Equipment : irradiation device ................. air conditioning ................... power generating set, furniture, office equipment, miscellaneous equipment .......................... - Vehicle ........................................ OPERATION - Animals ........................................ 45,000 9,000 - Water, power supply ............................ 120,000 24,000 - Secretariate, Post Office ...................... 25,000 5,000 - Documentation .................................. 18,000 3,600 - Light equipment, glassware, products ........... 60,000 12,000 - Equipment for pilot test ....................... 35,000 7,000 - Maintenance of buildings and equipment ......... 13,000 2,600 - Operation and maintenance of vehicles .......... 120,000 24,000 2,394,ooo 578,800 330,000 460,000 280,000 140,000 120,000 24,000 50,000 10,000 1,380,OOO 276,000 66,000 92,000 56,000 28,000 436.000 87,200 -7- 11 - RESEARCH ON TRYPANOTOLERANCE STAFF F.F. us $ - Expatriate : 2 reserchears (protozoologist and biochemist) 1,420,OOO 284,000 2 senior technicians (serologist and hemato: logist) . . . . . . ..*....................*.... 1,060,000 212,000 1 electronician *..*..*..................... 500,000 100,000 1 ranch manager ..*..........*.......*..,... 410,000 82,000 6 laboratory assistants . . . ..*........*s.... 1,500,000 300,000 - African : 20 drivers, 4 laboratory aids, 6 labourers, 10 shepherds ..*.*....*......*..*..*.*...... 356,000 71,200 5,246,OOO 1,049,000 INVESTMENTS - Technical buildings ..a*..........*..*.......*.. 620,000 124,000 - Housing . ...*.............,..........,.......*.* 1,212,ooo 242,400 - Equipment : furniture, office equipment, laboratory equipment . . . . . . . . . . . . . . . 225,000 45,000 - Vehicles .**..,..,....*....,..................,. 100,000 20,000 2,157,OOO 431,400 OPERATION - Animals ........................................ 90,000 18,000 - Water, gas, power supply ....................... 200,000 40,000 - Secretariate, Post Office ...................... 30,000 6,000 - Documentation .................................. 20,000 4,000 - Light equipment, glassware, products ........... 80,000 16,000 - Maintenance of buildings and equipment ......... 20,000 - 4,000 - Operation and maintenance of vehicle ........... 240,000 48,000 680,000 . 136,000 ’ -8- SUMMARY I - BIOLOGICAL ACTION AGAINST TSETSE FLIES - Staff .............................. - Investments ........................ - Operation .......................... - Contingencies ...................... II - RESEARCH ON TRYPANOTOLERANCE - Staff .............................. - Investments ........................ - Operation .......................... - Contingencies ...................... III - TOTAL F.F. us $ 2,894,OOO 578,800 1,380,OOO 276,000 436,000 87,200 290,000 58,000 5,000,000 1 ,ooo,ooo 5,246,OOO 2,157,OOO 680,000 817,000 8,900,OOO 13,900,000 2,780,OOO 1,049,200 431,400 136,000 163,400 1,780,OOO . 1 dollar - 5 FF 

Research Programme Concerning Trypanosomiases and their Vectors

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Research Programme Concerning Trypanosomiases and their Vectors

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