Tag Archives: University of Nairobi

Reducing aflatoxins in Kenya’s food chains: Filmed highlights from an ILRI media briefing

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Last month (14 Nov 2013), the International Livestock Research Institute (ILRI) held a roundtable briefing/discussion for science journalists in Nairobi to highlight on-going multi-institutional efforts to combat aflatoxins in the food chains of Kenya.

Aflatoxins are a naturally occurring carcinogenic by-product of common fungi that grow on grains and other food crops, particularly maize and groundnuts. Researchers from across East Africa are joining up efforts to address the significant human and animal health challenges posed by these food toxins in the region.

Watch this 6-minute film, which highlights some of the interventions being used to tackle aflatoxins in Kenya. The film features interviews with the five panelists at the media briefing, who came from the University of Nairobi, the US Centers for Disease Control and Prevention (CDC) in Kenya, the International Institute of Tropical Agriculture (IITA), the Biosciences eastern and central Africa (BecA)-ILRI Hub, and ILRI.

‘Even though the presence of aflatoxins in Kenya dates back to the 1960s, the first recorded outbreak of aflatoxins that affected humans was recorded in the early 1980s,’ says Erastus Kang’ethe, a professor in the Department of Public Health at the University of Nairobi.

‘The biggest risk of aflatoxins comes from long-term exposure to these toxins, which leads to chronic aflatoxicosis,’ says Abigael Obura, of CDC. ‘The CDC in Kenya is working closely with the Ministry of Health to improve aflatoxin surveillance measures in Kenya’s districts through better sample collection and analysis.’

At the same time, Johanna Lindahl and other scientists at ILRI are assessing the risks posed by aflatoxins in Kenya’s dairy value chain; cows that consume aflatoxin-contaminated feeds produce milk that is also contaminated with the toxins.

According to Charity Mutegi, from the International Institute of Tropical Agriculture, one of the key strategies in managing aflatoxins in Kenya is by using a ‘biological control technology that targets the fungus that produces the aflatoxins while the crop is still in the field.’ Known more popularly as ‘aflasafe,’ this technology, which is expected to be available in the country soon, is in use in other parts of Africa where ‘farm trials have yielded aflatoxin reduction of over 70 percent,’ says Mutegi.

Jagger Harvey, a scientist with the BecA-ILRI Hub, says the hub has established a capacity building platform for aflatoxin research that is being used by maize breeders from Kenya and Tanzania to, among other control efforts, come up with maize varieties that are more resistance to the aflatoxin-causing fungus.

Read a related ILRI news article about a filmed interview of two scientists leading work of the CGIAR Research Program on Agriculture for Nutrition and Health, Delia Grace, of ILRI, and John McDermott, of the International Food Policy Research Institute, who describe some of the risks aflatoxins pose, new options for their better control and why research to combat these toxins matters so much.

View an ILRI infographic of the impact of aflatoxins in the food chain.

Read more on biological control to reduce aflatoxins.

Read more on strengthening regional research capacity to deal with aflatoxins.

Livestock in the city: New study of ‘farm animals’ raised in African cities yields surprising results

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Urban zoonoses and food safety: Nairobi

Leonard Gitau, a small-scale livestock farmer in Dagoretti, Nairobi, speaks to journalists during a media tour by ILRI of urban farmers in Nairobi on 21 Sep 2012 (photo credit: ILRI/Paul Karaimu).

For the first time in history, more people are living in cities than rural areas. Many of them still keep livestock. At least 800 million people in cities in developing countries practice urban agriculture, from growing vegetables to keeping camels—often in close confinement in densely populated areas.

The benefits of urban livestock keeping are many: from improved food security, nutrition and health from livestock products, creation of jobs and protection from food price volatility. But the risks in urban livestock are also large: unsanitary conditions and weak infrastructure mean that livestock can be a source of pollution and disease.

‘Zoonoses’, diseases transmitted between animals and people, are a global health problem that particularly affects the poor in developing countries. A new study by the International Livestock Research Institute (ILRI) and partners finds that zoonoses and diseases recently emerged from animals make up 26% of the infectious disease burden in low-income countries, but just 0.7% of the infectious disease burden in high-income countries.

The study, published in the journal Tropical Animal Health and Production, which was led by University of Nairobi and ILRI, is part of a series of papers that examine the facts and fiction of urban livestock keeping. The researchers note the need for evidence in the planning and practice of urban food systems and the danger of relying on perceptions or models taken from different contexts.

Here are some of the results of the study.

LOTS OF URBAN LIVESTOCK
Much more livestock is being raised in the urban areas of developing countries than most people (and policymakers) think.

THE DISEASE RISK
Domestic as well as wild animals can spread many, and some very serious, diseases to people and it is a reasonable assumption that as the population of urban areas of these and other developing countries continues to increase, the risk of zoonoses also increases.

THE GOOD NEWS
This recent in-depth study of urban zoonoses in urban environments in Nigeria and Kenya suggests that the human disease risk posed by raising, processing, marketing and/or consuming livestock in cities, city suburbs and big towns in developing countries is less than we might think.

SUPPORT INFORMAL MARKETS
Rather than bar poor people from livestock enterprises in urban areas in an attempt to protect public health, which could do the poor more harm than good, this study suggests that a more practical and equitable course is to work to enhance practices in small-scale urban livestock raising and informal livestock marketing by encouraging poor livestock producers, processors and sellers to upgrade some of their practices.

PROVIDE INCENTIVES FOR GOOD BEHAVIOUR
This study included participatory work with the local communities, and an important outcome has been the success achieved by creating incentives for the poor to improve their livestock practices rather than trying to strictly regulate these informal livestock markets, or harass the people involved, or bar them from operating altogether.

DISEASE RISKS ARE NOT WHAT WE THINK
Another important finding is that people are not the good judges of risks that they think they are; most people, including food safety officials, think that livestock foods, being so perishable, carry the greatest risk of disease in informal urban markets, but studies have shown that, for example, city vegetables are often a greater cause of disease concern than milk and meat.

TRACKING PATHOGENS AND RELATED ILRI RESEARCH
This research project was conducted jointly with the University of Nairobi, whose Professor Erastus Kang’ethe led the data collection and participatory work within Kenya, with the support of the Kenyan government and health officials. This project also expands ILRI’s long-standing research on informal dairy markets in East Africa and South Asia, led by ILRI scientist Amos Omore and others, which helped to refine dairy policies to support rather than harass sellers of ‘raw’ (unpasteurized) milk. And a new ILRI research project led by ILRI scientist Eric Fevre will investigate zoonoses further by tracking disease pathogens as they move among farms, processors and markets in Nairobi.

Urban zoonoses and food safety: Nairobi

ILRI scientist Delia Grace is interviewed by BBC and AllAfrica.com before the start of a journalist tour of urban livestock farmers in Nairobi that ILRI organized on 21 Sep 2012 (photo credit: ILRI/Paul Karaimu).

Delia Grace, an ILRI veterinary epidemiologist and leader of a component of the CGIAR Research Program on Agriculture for Nutrition and Health, was the principal investigator in the Ibadan-Nairobi zoonoses study and editor of this special edition of Tropical Animal Health and Production. Grace says that regulations that work for rich countries do not always work for poor countries, and that policies should follow a risk-based approach where decision-makers’ focus is not the bugs present in food but the likely effects on human health. ‘The risks of food-borne diseases’, she says, ‘need also be weighed against the economic benefits and nutrition abundantly supplied by animal products.’

In the absence of evidence, policies are based on the prejudice that urban livestock keeping is unsafe and unmodern, and it is often banned outright. Of course it continues behind hedges and in back alleys, but the imposed illegality drives a rush to the bottom in hygienic practices and investments. When farmers are harassed by authorities and operate in a legal grey area, they have little access to the support they need and little incentive to invest in business improvements.

Thanks in part to previous research on the benefits of urban agriculture, the Government of Kenya has been proactive in posting veterinary, animal production, and crop personnel in major urban centers to lead from the front in championing the development of urban agriculture. The government has also led in the development of the urban agriculture and livestock policy. Involving these civil servants has been key in enabling our research in urban agriculture. This is a good example of government changing its policy to better meet the needs of citizens.

Rapid urbanization, and along with it the urbanization of poverty and food insecurity, raises urgent challenges for the global research and development community. Among them is the need to manage the growing risks of zoonosis associated with urban farming and to improve food safety for the one billion of the world’s poor living in cities, most of whom depend on informal markets instead of more formal government-organized markets or grocery stores.

Informal, or wet markets, exist in many different forms across Africa and Asia but have common characteristics: food escapes effective health and safety regulation; many retailers do not pay tax and some are not licensed; traditional processing, products and retail practices predominate; infrastructure such as water, electricity, sanitation, and refrigeration is lacking; and little support is provided from the public or non-governmental sector. Unsurprisingly, women and the poor are involved most in informal markets.

Applying an innovative research approach known as ‘ecohealth’, the findings of this research contradict some basic assumptions about zoonoses and urban farming and show how livestock keepers in one of Africa’s biggest cities, Nairobi, Kenya, are transforming their livestock and public health practices to combat disease and help feed a city where 60% of the population lives in slums.

But what does it mean in practice? A special edition of 11 papers sets out how ecohealth approaches can make a difference to city health. The researchers base their findings from two case studies. One is in Dagoretti, a Nairobi district of some 240,000 residents, and analyzes the emerging zoonoses cryptosporidiosis, a diarrhoeal disease that is passed from cattle to humans.

For further information

See a Factsheet on Urban Agriculture and Zoonoses in Nairobi, which provides key facts about urbanization, urban livestock keeping and the study in Dagoretti, where most residents are poor and many raise livestock inside city limits.

Read the special supplement of the August 2012 issue of the journal Tropical Animal Health and Production on assessing and managing urban zoonoses and food-borne disease in Nairobi and Ibadan.

Featured in the special supplement are the following 10 research articles by scientists from the International Livestock Research Institute (ILRI) and partners from the Kenya Agricultural Research Institute (KARI), the Kenya Ministry of Agriculture, the Federal University of Agriculture, Abeokuta, the University of Ibadan and the University of Nairobi.

Click on the links below to read the abstracts of the articles (ILRI authors in burgundy; journal subscription required for access to full text).

Improving cattle genetics with in vitro embryo production technology

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Livestock scientists from ILRI and the Clinical Studies Department of the University of Nairobi (UON) recently succeeded in breeding Kenya’s first test-tube calf using a technique called in vitro embryo production (IVEP). IVEP makes it possible to rapidly multiply and breed genetically superior cattle within a short generation interval.
Why is this important?
For several reasons. First, livestock is the fastest growing sub-sector in the world, as increasing trends of 114% in demand for meat and 133% for milk attest. To improve on food security, it is essential to double livestock production in the developing world by 2020. IVEP is clearly one of the most efficient ways to accomplish this.

Second, let’s consider the problem of environmental impact. Doubling livestock production through traditional breeding techniques increases pressure on natural resources—water, land and biodiversity. So the need for enhanced efficiency without degrading natural resources is urgent. Again, IVEP, which requires only laboratory equipment in the production process, comes to the rescue.

Third, there is the biodiversity issue. Matching genotypes to environment is crucial. Scientists need to take several factors into consideration—among them adaptation, tolerance for disease, tolerance for new environments and alignment to market development. Although plenty of genetic diversity exists, thus far we’ve done little with it. Once more, IVEP could be the answer.

Fourth, IVEP has significant commercial potential because farmers can rent their best cows as donors and their lower-quality cows as surrogates.

Most importantly, we need to look closely at the constraints faced by small-scale livestock keepers.

  • Cattle genotypes and production environments, as often as not, do not match. Result:  low productivity.
  • Heifer replacement programs take a long time and are rarely done properly. Result: supply is low, prices are high.
  • Sex ratios are often disadvantageous. Result: too many males and high production costs.
  • The commercial relevance of many indigenous breeds is not optimised. Result: farmers incur unsupportable losses.
  • Programs for breed conservation and preservation are often improper. Result: some breeds are threatened by extinction and no gene pool for replacement exists.

IVEP does not—and should not—completely replace traditional reproductive technologies such as conventional embryo transfer (ET) and artificial insemination. Each of these techniques has its place, and each of them utilizes tissues, embryos and semen for improvement and reconstruction of cattle breeds. The difference is that while the traditional ET techniques involve more animals and are wholly done in the field, IVEP is undertaken in the lab and involves fewer surrogate animals in the field. IVEP eliminates the tedious steps of synchronizing donor cows.

Specifically, IVEP technology as a breeding tool has the distinct advantage of maximizing utilization of appropriate dam and sire genotypes by:

  • increasing efficiency of multiplication in breeding;
  • permitting  determination of sex of the offspring; and
  • permitting pre-testing of actual fertility status of the bull.

Thus, while natural mating or artificial insemination are necessarily slow and inefficient, producing only 10-15 offspring per life span of a cow …

…IVEP can produce up to 300 offspring per life span.

The SIFET Project: a successful IVEP program
The Sexed semen in-vitro fertilization and embryo transfer (SIFET) project was designed to exploit and promote the potential of applying IVEP reproductive technique to:

  • develop, multiply and disseminate female crossbreeds that appropriately match with production environment;
  • provide a system to preserve top bovine genotypes in cases of accidental culling in a recycle-like scheme (slaughterhouse collection); and
  • identify, multiply and conserve selected superior desirable breed traits.

The project involved collecting ovaries from slaughter houses or picking ovum from live cows. When the genetic material is brought to the lab, oocytes with high developmental competence are selected and morphological evaluation done. Once the ideal oocytes are identified, they are matured in vitro for 22-24 hours. The subsequent in vitro fertilization process is conducted for a period of 18-22 hours with a high sperm concentration. The fertilization itself requires removal of seminal plasma and extenders, separation of motile sperms from dead ones and induction of sperm capacitation. Once the embryos are formed, they are cultured in the lab for 7 days and then transferred to surrogates.

A conception rate of about 40% has been achieved, with calves born without abnormalities.

Conclusions

  1. IVEP technology is feasible in Kenya.
  2. Commercialization of the process should be facilitated as soon as supportive policies and proper legal/regulatory frameworks are in place

Challenges
Poor field heat detections leading to poor uterine synchrony and lower conceptions are concerns, as is the high genotype variability characteristic of animals brought to slaughterhouses.

Way forward and prospects
Looking ahead, the collaborating scientists anticipate bringing ovum pick-up (OPU) and cryopreservation into the picture as well as capacity building.

Clearly, such programs can help match breeds to appropriate production systems to ensure sound breeding programs. Where and when necessary, new breeds can be introduced within a relatively short period of time. Above all, embryos are far easier to transport across continents than live animals.

Through IVEP technology and well-planned crossbreeding programs such as SIFET that integrate the use of indigenous cows as donors and surrogates while using semen from appropriate (more productive and reasonably adapted) dairy breeds such as Jerseys, F1 heifers suited to the smallholder farmers’ conditions can be produced.

Niche markets for the technology and its F1 products should be further explored and exploited, notably with regard to the potential of forestalling the threat to key wildlife species.

Acknowledgements
Funding for the project was made available by Heifer Project International. UON provided the technical team and recipient animals. Administration and laboratory facilities were provided by ILRI. The cooperation of the abattoirs (the source of ovaries) and the animal owners are gratefully acknowledged. The capacity building program through a joint CNPq grant for the Embrapa-UON-ILRI partnership, as well as support from Dr Luiz Carmago and Dr Joao Viana of Embrapa, are highly appreciated.

The collaborating scientists are Mwai Okeyo, Henry Mutembei and Bridgit Syombua from ILRI; and  Erastus Mutiga, Victor Tsuma and Henry Mutembei from Clinical Studies, UON.

For more information, contact Dr Okeyo Mwai, Animal Geneticist/Breeder, Biotechnology Theme, ILRI, at o.mwai@cgiar.org.