Department and School: Faculty of Biological Sciences; University of Ngaoundere
Compared to the other continents, Africa is lacking behind in terms of reaching its full potential of agricultural output, which is in dire need to nurture its ever growing population. Modern innovations in the field could help to alleviate this gap. I would like to focus on the improvement in productivity of Africa’s livestock, i.e. cattle, goat, sheep, chicken, etc. by optimizing their genetic composition to our continent’s environment. In particular, the resilience against the many prevailing diseases of veterinary importance shall be increased.
In developed countries, the domestic breeds are highly adapted to the local conditions and optimized for high productivity. Although there are also African indigenous breeds, which are well adapted, their productivity is significantly lower than newly introduced ones. For instance, the taurine Bos taurus cattle breed is more resistant to African trypanosomosis, which is normally deadly for the introduced Zebu breed Bos indicus if left untreated. Africa detains a great potential in livestock diversity, which could be the base of ameliorating the gene pool of economically important breeds, therefore reaching higher levels of meat and dairy productivity. This diversity is, however, threatened, since indigenous breeds only represent a tiny fraction of the total livestock population due to their low economic importance.
Infectious diseases are among the factors with highest impact for curbed livestock productivity in the developing world, generating estimated losses of 35 to 50% of the livestock industries turnover (Whitelaw & Sang, 2005). Current disease control strategies rely mainly on drug and vaccine administration. However, several factors have prevented the success of this approach, such as the retreat of state veterinary services, unaffordable financial burden for small-scale farmers, lack of awareness among livestock keepers resulting in inappropriate treatment applications, and the development of drug resistances (Awa & Achukwi, 2010). Alternative technologies like the improvement of natural host resistance by marker-assisted selection would provide a save, cost-effective and sustainable way for increasing livestock productivity in sub-Saharan Africa (Orenge et al., 2011). DNA SNP fragments and/or microsatellites would act as genomic biomarkers for this purpose. At first, animals of different breeds from regions with high prevalence of veterinary pathogens have to be examined and blood samples collected. Then, DNA shall be extracted to detect and identify blood parasites. Next, the host genome shall be analyzed by molecular tools to search for Quantitative Trait Loci (QTL) indicating the susceptibility or resistance, respectively, against the parasite in question. These loci permit a better understanding of the genetic architecture of a trait and the identification of candidate genes for resistance.
High throughput testing of biomarkers for such loci on a large number of animals/breeds could identify those with the highest rates of resistance to Africa’s most devastating livestock diseases and select them for breeding programs. This would be fundamental for creating more productive and pathogen-resistant animal breeds, therefore satisfying the growing demand for meat and dairy products and providing a sustainable livelihood for those small-scale pastoralists, which are the backbone of Africa’s society.