Trypanotolerance in N’Dama x Boran crosses under natural trypanosome challenge: effect of test-year environment, gender, and breed composition

BMC Genetics

Morris Soller⁷  Olivier Hanotte²  John P Gibson³  Abraham Korol⁴  Steve Kemp⁵  Charles N Kimwele⁶  Leonard Munga¹  Caleb O Orenge¹ 

[1] Kenya Agricultural Research Institute - Trypanosomiasis Research Centre (KARI-TRC), P.O. Box 362, Kikuyu, Kenya;School of Biology, University of Nottingham, Nottingham, NG7 2RD, UK;The Centre for Genetic Analysis and Applications, University of New England, Armidale, NSW, 235, Australia;Department of Evolutionary and Environmental Biology, Institute of Evolution, University of Haifa, Haifa, 31905, Israel;International Livestock Research Institute (ILRI), Nairobi, Kenya;Department of Veterinary Anatomy and Physiology, University of Nairobi, Nairobi, Kenya;Department of Genetics, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel

关键词: Sub-Saharan Africa;    Gender effect;    N’Dama x Boran crosses;    Boran;    N’Dama;    Tsetse challenge;    Trypanotolerance;   

Others  :  1121348
DOI  :  10.1186/1471-2156-13-87

 received in 2012-06-05, accepted in 2012-10-11,  发布年份 2012

【 摘 要 】

Background

Trypanosomosis, a protozoal disease affecting livestock, transmitted by Glossina (tsetse) flies is a major constraint to agricultural production in Sub-Saharan Africa. It is accepted that utilization of the native trypanotolerance exhibited in some of the African cattle breeds to improve trypanotolerance of more productive but susceptible breeds, will offer a cost effective and sustainable solution to the problem. The success of this approach is based on the premise that quantitative trait loci previously identified under relatively controlled situations confer useful trypanotolerance under natural field situations. As part of a study to authenticate this hypothesis, a population of 192 cattle, consisting of six batches of N’Dama and Kenya-Boran backcross animals [(N’Dama x Kenya-Boran) x Kenya-Boran] born over the period 2002 to 2006 was constructed. Some of the batches also included pure Kenya-Boran cattle, or N’Dama x Kenya- Boran F1 animals. Each batch was exposed as yearlings to natural field trypanosomosis challenge over a period of about one year; the entire challenge period extending from December 2003 to June 2007. Performance of the animals was evaluated by weekly or biweekly measurements of body weight, packed blood cell volume (PCV), parasitemia score, and number of trypanocide treatments. From these basic data, 49 phenotypes were constructed reflecting dynamics of body weight, packed cell volume (PCV) and parasitemia under challenge.

Results

Females were distinctly more trypanotolerant than males. F1, backcross and pure Kenya- Boran animals ranked in that order with respect to trypanotolerance. Overall batch effects were highly significant (p<0.001) for most traits, and were generally more significant than the gender or genetic type effects. The superior trypanotolerance of the F1 animals was expressed in all three components of animal defense strategies against pathogens: Avoidance resistance, and tolerance.

Conclusions

The results show that trypanotolerance derived from the N’Dama is expressed under field conditions; and that the trait is primarily additive in nature, being expressed in heterozygous condition and in a three-quarters Boran genetic background. The results further, underscore the complexity of the trait in the field manifesting all three host disease-control strategies, and show the importance of gender and local environmental conditions in determining response to challenge.

【 授权许可】

   
2012 Orenge et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

【 参考文献 】

• [1]D’leteren G, Authie E, Wissocq N, Murray M: Exploitation of resistance to trypanosomes. In Breeding for disease resistance in Farm Animals. Second edition. Edited by Axford RFE, Bishops SC, Nicholas FW, Owen JB. CAB International Wallington, UK; 1999:195-216.
• [2]d’leteren GDM, Authie E, Wissocq N, Murray M: Trypanotolerance: An option for sustainable livestock production in areas of risk from trypanosomosis (Review). Revue Sci Tech l’office Int Epiz 1998, 17:154-175.
• [3]d’leteren G, Authie E, Wissocq N, Murray M: Exploitation of resistance to trypanosomes. In Axford R.F. E; Bishops S. C.; Nicholas F. W. and Owen J. B. (eds). Breeding for disease resistance in Farm Animals. Second edition. CAB International Wallington, UK,  ; 1999:195-216.
• [4]Murray M, Morrison WI, Murray PK, Clifford DJ, Trail JCM: Trypanotolerance:A review. World Animal Review, 37 (January- March). Food and Agriculture organization of the United Nations, Rome; 1981:36-47.
• [5]Murray M, Morrison WI, Whitelaw DD: Host susceptibility to African trypanosomiasis-trypanotolerance. Adv Parasitol 1982, 21:1-68.
• [6]Murray M, Dexter TM: Anaemia in bovine African trypanosomiasis. Acta tropical 1988, 45:389-432.
• [7]Njogu AR, Dolan RB, Wilson AJ, Sayer PD: Veterinary Records. 1985, 117:632-636.
• [8]Dolan RB: Genetics and trypanotolerance. Parasitology Today 1987, 3:137-143.
• [9]Dolan RB: The Orma Boran: A trypanotolerant East African Breed. Fifteen years of research on Galana Ranch in Kenya. Kenya Trypanosomiasis Research Institute, Kikuyu, Kenya; 1998:96.
• [10]Mwangi EK, Stevenson P, Gettinby G, Murray M: Variation in susceptibility to tsetse-borne trypanosomiasis among Bos indicus cattle breeds in East Africa. In Towards increased use of trypanotolerance: current research and future directions (G.J. Rowlands & A.J. Teale, eds). Proceedings of a workshop organised by the International Livestock Centre for Africa (ILCA) and the International Laboratory for Research on Animal Diseases (ILRAD). ILRADALCA, Nairobi, Nairobi, Kenya; 1993:81-86.
• [11]Hanotte O, Ronin Y, Agaba M, Nilsson P, Gelhaus A, Horstmann R, Sugimoto Y, Kemp S, Gibson J, Korol A, Soller M, Teale A: Mapping of quantitative trait loci controlling trypanotolerance in a cross of tolerant West African N’dama and susceptible East African Boran Cattle. Proc Natl Acad Sci U S A 2003, 100:7443-7448.
• [12]Orenge CO, Munga L, Kimwele C, Kemp S, Korol A, Gibson J, Hanotte O, Soller M: Expression of trypanotolerance in a N’Dama x Boran crosses under field challenge in relation to N’Dama genome content. BMC Proc 2011, 5(Suppl 4):S23. BioMed Central Full Text
• [13]Bett B, Orenge C, Irungu P, Munga L: Epidemiological factors that influence time-to-treatment of trypanosomosis in Orma Boran cattle raised at Galana Ranch, Kenya. Vet Parasitol 2004, 120:45-53.
• [14]Turay AA, Nwobu GO, Okugun GRA, Igone CU, Adeyeye K, Aghatise KE, Okpala HO, Talfeng YM: A comparative study on susceptibility of male and female albino mice to Trypanosome brucei brucei. J Vect Borne Dis 2005, 42:15-20.
• [15]Ogunsanmi A, Taiwo V, Onawumi B, Mbagwu H, Okoronkwo C: Correlation of physiological plasma lipid levels with resistance of cattle to trypanosomiasis. Veterinarski Arhiv 2000, 70(5):251-257.
• [16]Murray YM, Trail JCM, Black SJ: Genetic resistance to African trypanosomiasis. J Infect Dis 1984, 149:311-319.
• [17]Medzhitov R, Schneider DS, Soares MP: Disease tolerance as a defense strategy. Science 2012, 335:936-941.
• [18]Naessens J, Leak SGA, Kennedy DJ, Kemp S, Teale AJ: Response of haemopoietic chimera twin cattle from susceptible and tolerant genetic backgrounds to experimental infection with Trypanosoma congolense. Vet Parasitol 2003, 111:125-142.
• [19]Dargie JD, Murray PH, Murray M, Grimshaw WRI, McIntyre WIM: Bovine trypanosomosis: the red cell kinetics of N’Dama and Zebu cattle infected with Trypanosoma congolense. Parasitology 1979, 78:271-286.
• [20]Paris J, Murray M, McOdimba F: A comparative-evaluation of the parasitological techniques currently available for the diagnosis of African trypanosomiasis in cattle. Acta Trop 1982, 39:307-316.