Trypanotolerance
A trypanotolerant organism is one which is
By host
In livestock
Some breeds are known for their trypanotolerance. This is especially important in Africa where a few particular trypanosomes are major economic and agricultural pests.[1][2][3][4]
Trypanotolerant livestock breeds
- N'Dama cattle[2]
- West African Dwarf goats[5]: 106
- West African Dwarf sheep (Djallonké)[6]
- Cameroon sheep
Trypanotolerance of the N'Dama Cattle and West African Dwarf Sheep and Goats
Certain domestic ruminant breeds in sub-saharan Africa show remarkable resistance to the effects of African
The trypanotolerance trait is seen in N'Dama cattle, and it refers to the N'Dama cattle's ability to survive in areas with high tsetse fly endemicity, where other cattle breeds would frequently contract trypanosomiasis.[1] In areas or locations of low to moderate tsetse fly challenge, typanotolerant N'Dama cattle show lower numbers of parasites in their blood, develop less severe anemia and have also been shown to be more productive.[8]
An investigation to test the resistance of different small ruminant breeds (West African dwarf sheep and goats) to an artificial infection with
Trypanotolerance appears to include both non-immunological and
In addition to the above-listed criteria, studies have shown that the effective dose of the trypanosome parasite that these animals acquire following the bite of the tsetse fly is also a consideration. It only takes one fly bite to transmit the infection. [11] The quantity of trypanosomes injected into an animal's skin as a result of bites determines how severe the sickness will be; thus, trypanotolerance during natural exposure may be influenced by lower infective dosages.[7] The finding that some cattle that are highly resistant in the field don't always retain that level of resistance after being artificially infected with a specific dose of the parasite may be supportive of this hypothesis.[12]
History of genetic research
Trypanotolerance had previously been achieved through normal livestock breeding in cattle, but genetic analysis was becoming a serious option in the 1980s. The effort that would eventually bear fruit began with a conversation between Peter Brumby - then at the International Livestock Centre for Africa - and Morris Soller in 1985. This was followed by the opening of the shortlived International Trypanotolerance Center in the Gambia in 1987 with a seminar on the genome mapping project that would continue beyond the Center itself. The project was then actually completed by the ILRI - the successor to the ILCA - in 2003.[13]
References
- ^ S2CID 1188831.
- ^ PMID 28499406.
- ^ "Trypanotolerant livestock in the context of trypanosomiasis intervention strategies". Food and Agriculture Organization of the United Nations. Retrieved 2021-02-20.
- ^ "Trypanotolerance in West African cattle". CIRAD (Centre de coopération internationale en recherche agronomique pour le développement). Retrieved 2021-02-20.
- ISBN 9789251029985.
- S2CID 86116225.)
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: CS1 maint: DOI inactive as of January 2024 (link - ^ S2CID 42585897.
- S2CID 3253779.
- ^ a b
- This review...
- • Murray, M.; Trail, J.; d'Ieteren, G. (1990). "Trypanotolerance in cattle and prospects for the control of trypanosomiasis by selective breeding". S2CID 83754228.
- PMID 19200783.
- ^ ISBN 9782709923767.
- PMID 6.
- S2CID 46733451.