A new study will use advanced tools to track 1,000 years of African pastoral ranching and identify traits that will help cattle survive heat, drought, and disease progression.
Scientists today (Sep 28, 2020) announced the discovery of a new set of detailed genetic markers and information in African cattle associated with valuable traits such as heat and drought tolerance, the ability to control inflammation and tick infestation, and resistance to devastating Animal diseases such as trypanosomiasis.
The results, published in the October issue of Natural geneticsarose from a joint effort by scientists from the Addis Ababa and Nairobi-based International Livestock Research Institute (ILRI) of the Seoul National University (Republic of Korea) of the Rural Development Agency (RDA, Republic of) to sequence the genomes of 172 indigenous cattle (Korea), University of Khartoum (Sudan), Center for Genetics and Health of Tropical Farm Animals (CTLGH, Scotland), Swedish University of Agricultural Sciences (Sweden) and University of Nottingham (UK). They wanted to learn how cattle – after spending thousands of years in a changing patchwork quilt of subregions in Africa – evolved rapidly over the past millennia with traits that enabled them to thrive across the continent.
“We believe these findings can be used to raise a new generation of African cattle that share some of the characteristics of European and American farm animals – which produce more milk and meat per animal – but with the rich mosaic of traits that are African Making cattle more resilient and sustainable, ”said Olivier Hanotte, Principal Scientist at ILRI, Professor of Genetics at the University of Nottingham and Program Director at CTLGH who led the work at ILRI.
Hanotte and his colleagues embarked on a kind of “genomic journey through time” that enabled scientists for the first time to understand the genetic journey that made African cattle so adaptable. They discovered what co-author Steve Kemp, director of the ILG LiveGene program and assistant director of CTLGH, referred to as the “evolutionary jolt” that occurred 750-1050 years ago: the arrival of Asian cattle breeds in East Africa with genetic traits that produce cattle production would be possible in diverse and demanding African environments.
The genome sequencing work revealed evidence that indigenous pastoralists began to breed Asian cattle known as zebu with local cattle breeds known as taurine. In particular, the zebu offered traits that would enable cattle to survive in hot, arid climates typical of the Horn of Africa. However, by crossing the two animals, the newly created animals also retained the taurine’s ability to endure humid climates, where vector-borne diseases such as trypanosomiasis are common.
“Farm animals – especially cattle – can be controversial, but without them millions of people in Africa would have been forced to hunt wildlife for protein,” said author Ally Okeyo Mwai, a senior researcher at ILRI who runs the African Dairy Genetic Gains program “directs. “That would have been devastating for the African environment and its incredible diversity of wildlife.”
It is now important to harness the full range of natural genetic makeup that has made African cattle so resilient in order to sustainably meet Africa’s growing demand for milk and meat while minimizing the negative effects of increased animal production. For many households in Africa, and especially for the poorest, livestock in general and livestock in particular continue to be a family’s most valuable asset. In addition to income, they provide an important source of protein and micronutrients, for example to pay school fees. They also provide manure for crops, and some African breeds of cattle can survive in conditions that food crops cannot support, providing farmers with a potential adaptation strategy to address climate change.
“We are fortunate that pastoralists are such skilled breeders,” said Hanotte. “They have left a valuable roadmap for efforts by ILRI and elsewhere to balance animal productivity in Africa with resilience and sustainability.”
“Studying the genomes of native cattle shows that breeding to adapt to the environment was key to successful livestock production in Africa,” said Kemp. “And that needs to be taken into account in our future efforts to develop more productive and sustainable animals. If the goal is pure productivity, you are doomed. ”
“It is important to understand that livestock has long played an important role in maintaining the health and prosperity of African communities,” said ILRI Director General Jimmy Smith. “The breeding focus on resilience that has guided efforts so far is a touchstone for future work to identify a sustainable pathway for animal production in sub-Saharan Africa.”
Reference: September 28, 2020, Natural genetics.
DOI: 10.1038 / s41588-020-0694-2
About the International Livestock Research Institute (ILRI)
The International Livestock Research Institute (ILRI) is a nonprofit that helps people in low and middle income countries improve their lives, livelihoods and lands through the animals that are the backbone of smallholder agriculture and entrepreneurship in the United States Developing countries remain. ILRI is a CGIAR research center hosted by Kenya and Ethiopia along with 14 other offices in Africa and Asia.
thanksgiving
This work was supported by a grant from the BioGreen 21 Next Generation Program and Post Genome Project (Project Numbers PJ01323701 and PJ01040601) from the Rural Development Administration, Republic of Korea. Cattle population sampling was supported by the CGIAR CRP for Livestock and Fish (Uganda and Ethiopia), the University of Khartoum (Sudan) and the National Biotechnology Development Agency (NABDA) (Nigeria). The following institutions and their staff helped with the sampling of the African cattle: ILRI Kapiti Ranch; the Ministry of Animal Resources, Fisheries and Reach (Sudan); the Ol Pejeta Conservancy (Kenya); the Institute for Biodiversity (Ethiopia); and the directors of the veterinary services and ranchers from Ethiopia, Kenya, Uganda and Sudan. The ILRI farm animal genomics program is supported by the CGIAR farm animal research program (CRP Livestock), supported by contributors to the CGIAR Trust Fund. This research was funded in part by the Bill & Melinda Gates Foundation and with UK assistance from the UK Foreign, Commonwealth and Development Office (Grant Agreement OPP1127286) under the auspices of the Center for Genetics and Health of Tropical Farm Animals (CTLGH), jointly established by became the University of Edinburgh, SRUC (Scotland’s Rural College) and the International Livestock Research Institute.
