New ILRI study finds high levels of aflatoxin in milk and dairy feeds in Greater Addis Ababa milk shed

Aflatoxins are highly toxic fungal by-products produced by certain strains of Aspergillus fungi in more than 40 susceptible crops including maize and groundnuts. Aflatoxins can be separated into aflatoxins B1, B2, G1 and G2.

When ingested, aflatoxin B1 is metabolized to aflatoxin M1 which is secreted into milk. Aflatoxin B1 is particularly important because it has been found in most foods and animal feeds and is highly carcinogenic.

Aflatoxins cause around 90,000 cases of liver cancer each year and are strongly associated with stunting and immune suppression in children. Aflatoxins in contaminated animal feed can lead to reduced animal productivity. They can end up in products like milk, meat and eggs, thus presenting a health risk to humans, with children being particularly susceptible.

In Ethiopia, previous studies have investigated aflatoxin contamination in staple cereals, red chili pepper and ground peas. Now, a new research study published in the journal Food Control (6 July 2015) has, for the first time, documented aflatoxin contamination in milk and dairy feeds in Ethiopia and the results show that milk and dairy feeds in the Greater Addis Ababa milk shed are highly contaminated with aflatoxins.

The cross-sectional study by scientists from the International Livestock Research Institute (ILRI) was carried out in the Greater Addis Ababa milk shed between September 2014 and February 2015 in order to detect and quantify the levels of aflatoxin M1 in samples of raw cow’s milk and aflatoxin B1 in samples of dairy feed.

The Greater Addis Ababa milk shed was selected because it is a rapidly intensifying system where aflatoxins are likely to be an increasing problem. A value chain approach was used, whereby production, processing and marketing of dairy feeds and milk were examined, as well as milk sold to consumers in Addis Ababa.

A total of 110 milk samples (100 from dairy farmers and 10 from milk traders) and 156 dairy feed samples (114 from farmers and 42 from feed producers, processors and traders) were collected and analysed by enzyme-linked immunosorbent assay (ELISA).

The study analysed all the commonly used dairy feeds such as mixed concentrate feed, brewery by-products, maize grain, pea hulls and silage. The most common ingredients in concentrate feeds were wheat bran, noug cake, pea hulls and maize grain.

All the milk samples were found to be contaminated with aflatoxin M1. Over 90% of the milk samples contained aflatoxin M1 levels that exceeded the European Union limit of 0.05 micrograms per litre. Out of a total of 110 milk samples, only nine contained aflatoxin M1 levels below 0.05 micrograms per litre.

Similarly, all the feed samples were contaminated with aflatoxin B1, with levels ranging from 7 to 419 micrograms per kilogram. Along the value chain from farmers to feed manufacturers and traders, the levels of aflatoxin contamination were fairly similar.

Out of a total of 156 dairy feed samples, only 16 contained aflatoxin B1 at a level less than or equal to 10 micrograms per kilogram. At the same time, 41 feed samples contained aflatoxin B1 at levels exceeding 100 micrograms per kilogram.

There was a significant association between aflatoxin B1 contamination in concentrate feeds and the presence of noug cake in the feed.

Noug (Guizotia abyssinica or Niger seed) is an oilseed crop that is indigenous to Ethiopia. Noug seed is pressed to produce noug oil while the remaining noug cake is sold as animal feed to feed processors and dairy farmers. Noug cake is becoming increasingly popular among dairy farmers in Ethiopia because its high nutrient content increases animal productivity.

Noug cakes were found to be highly contaminated with aflatoxin B1 (290–397 micrograms per kilogram) while the other feed components (wheat bran, maize grain and Brewer’s dry yeast) had relatively low levels of aflatoxin.

For this reason, the authors of the study recommend that further research on aflatoxin risk mitigation should focus on noug cake so as to effectively reduce the risk of aflatoxin contamination in peri-urban and urban dairy value chains in Ethiopia. Risk assessment of aflatoxins in noug seed and its by-products in other food chains should also be carried out.

In addition, there is an overall need to increase awareness of aflatoxins and to support risk mitigation practices along the entire dairy value chain.

“Policymakers and development organization need to support the dissemination of information about good agricultural and storage practices and other simple risk-reduction measures,” the authors conclude.

Citation
Gizachew D, Szonyi B, Tegegne A, Hanson J and Grace D. Aflatoxin contamination of milk and dairy feeds in the Greater Addis Ababa milk shed, Ethiopia. Food Control 59(2016): 773-779.

You may download a 4-page brief of the research article at http://hdl.handle.net/10568/67116

 

Europe Day 2015 celebrations feature aflatoxin research by Finland-funded FoodAfrica program

Harvested maize in Tete Province, Mozambique (photo credit: ILRI/Stevie Mann).

 

As part of celebrations in Nairobi last week to mark Europe Day 2015, the Finland-funded FoodAfrica program took part in an exhibition at the residence of the European Union Delegation to the Republic of Kenya where several project outputs were showcased.

FoodAfrica is a research and development program aimed at providing new knowledge and tools for researchers, decision-makers and farmers towards improved local food security. The program works in Benin, Cameroon, Ghana, Kenya, Senegal and Uganda.

Sara Ahlberg, a Finnish associate professional officer and PhD student attached to the International Livestock Research Institute in Nairobi, presented a poster that highlighted research approaches by the FoodAfrica program to reduce the risk of mycotoxins in the feed-dairy value chain in Kenya, namely,

• Integrated risk and economic assessment of the Kenyan feed-dairy chain
• Investigation of technologies and strategies to reduce mycotoxin risk in the feed-dairy chain
• Impact assessment of a package of post-harvest strategies for reducing aflatoxins in maize

View the poster, FoodAfrica – Reducing risk of mycotoxins

 

Why gender matters for food safety

The following is an excerpted version of a blog post originally published on the CGIAR Research Program on Agriculture for Nutrition and Health (A4NH) website.

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Some of the foods that would most enhance nutrition in diets in the developing world are also the riskiest in terms of food safety. Numerous health risks exist along the value chain for livestock and fish products, from production to consumption. In this post, Sophie Theis (Research Analyst, Poverty, Health, Nutrition Division, International Food Policy Research Institute) and Delia Grace (Program Manager, International Livestock Research Institute) relate findings from a recent A4NH/International Livestock Research Institute analysis of 20 livestock and fish value chains in Africa and Asia that reveal how gender differences in value chain participation influence risk exposure.

The results from the participatory risk assessment of these value chains are published in Grace et al. (2010) and a paper analyzing the gendered dimensions of risk is underway by Delia Grace, Sophie Theis, Kristina Roesel, Erastus Kang’ethe and Bassirou Bonfoh.

Selling milk in Ethiopia (photo credit: ILRI).

In rural Mali, a Fulani herder finishes milking a cow and hoists the calabash to his head, the milk sloshing gently in the vessel as he carefully carries the milk to Mariam, the woman he works for. By custom, Mariam has never milked a cow, but once the milk is in her domain, she is in charge of its business and use. Today she decides to keep this calabash for the family, since she has been able to sell milk at a favorable price often in the past week. She sets most aside to naturally sour, which will preserve it in the absence of refrigeration; the fermentation gives a sharp taste that consumers find thirst quenching in the hot season.

In the outskirts of Nairobi, Faith works the udders of her dairy cow. A male relative she has hired to help with the milking approaches with another pail of milk. She accepts it absentmindedly; she is already estimating the prices she will get selling the milk to neighbors and the local milk bar and considering whether she should invest the revenues in hiring another person.

In rural Mali, periurban Kenya, and many other parts of Africa, women play important and varied roles in livestock and fish value chains. The milk that Mariam and Faith helped to produce goes both to their families and to the market; it is also valued as gifts and in Mali as a sacrifice that brings blessing and protection against evil.

The decisions that Mariam and Faith make have bearings on many people’s nutrition: the quantity of milk that they keep for their household, how they apportion milk amongst household members, the use of the income from milk that they sell, and – less often acknowledged, but critical – the extent to which they effectively manage food safety risk, preventing contamination of the milk.

Many of the most nutritious foods, including animal source foods, are amongst the riskiest in terms of pathogen transmission. Meat, milk, fish and eggs provide plenty of nutrients for pathogenic organisms and can also carry infections from animals that harbor them to people. Food-borne disease persists as a major public health problem in Africa and Asia, where the majority of these foods are produced by smallholders, marketed through the informal sector, and sold in wet markets.

Food safety in these products is a major concern, as informal markets are important sources of food for the poor and tend to provide food that is more accessible, affordable, and compatible with local preferences for certain varieties of food and quantities than supermarkets.

Women like Mariam and Faith manage risk as they interact with informal markets by selling and buying food for their households. Informal value chains are complex, shaped by a number of actors. While risk management training interventions tend to focus on the owners of livestock or on actors only in one node of the value chain (e.g. butchers), risk management relies on all the actors along the value chain, from production, aggregation, processing, retail, and consumption. Many of these actors are women, and attention to local norms in the division of labor is critical for targeting food safety assessments and interventions.

Read the complete blog post on the A4NH website

 

BecA-ILRI Hub hosts aflatoxin research platform towards safe food and feed in Africa

Aflatoxin-contaminated groundnut kernels from Mozambique (photo credit: IITA).

Among the many research projects carried out by the Food Safety and Zoonoses program of the International Livestock Research Institute (ILRI) is one that aims to reduce the risk of mycotoxins in the feed-dairy value chain in Kenya so as to improve food safety and safeguard the health of consumers of maize and dairy products.

The project is developing cost-effective and incentive-based mycotoxin control strategies and solutions for use by poor farmers and other actors within the feed-dairy chain.

Mycotoxins are poisonous metabolites produced by various species of moulds. Aflatoxins are cancer-causing mycotoxins produced by the mould Aspergillus flavus.

Aspergillus can grow in a wide range of foods and feed and thrives under favourable growth conditions of high temperature and moisture content.

The main activities of the project are:

• risk assessment of the Kenyan feed-dairy chain to identify the best control options and provide risk managers with information for decision-making
• assessment of the economic costs of aflatoxins in Kenya’s dairy value chain and examination of the cost effectiveness of mitigation strategies
• investigation of technologies and strategies to reduce mycotoxins risk in the feed-dairy chain
• impact assessment of a package of post-harvest strategies for reducing aflatoxins in maize
• dissemination of evidence and building capacity of local researchers and postgraduate students through participation in designing surveys, fieldwork and data analysis

The project also applies participatory methods to develop and test strategies to mitigate the risk of mycotoxins in the feed-dairy chain.

These participatory methods engage farmers in action research on their fields so they can learn and adopt new technologies and disseminate the knowledge to other farmers.

The project is hosted in the aflatoxin research platform of the Biosciences eastern and central Africa (BecA) Hub at ILRI’s headquarters in Nairobi. The platform was set up to provide African scientists and their research partners access to state-of-the-art facilities for nutritional and aflatoxin analysis.

The February 2015 issue of the Aflatoxin Partnership Newsletter, published by the Partnership for Aflatoxin Control in Africa, highlights the aflatoxin platform in an article by Jagger Harvey, a senior scientist at the BecA-ILRI Hub.

Since its establishment in 2011, the platform has hosted work of more than 60 researchers from seven African countries, Australia, Europe and North America,” writes Harvey.

“Collectively, the community around the laboratory has made initial assessments of aflatoxin contamination in a number of countries, conducted the first inoculated field trials in the region to identify maize varieties less susceptible to aflatoxin accumulation, developed models estimating aflatoxin risk at harvest and produced a range of other important findings and tools which are beginning to reach end users to help ensure safer food and feed for Africa”.

 

ILRI research on animal health and food safety featured at the 6th All Africa Conference on Animal Agriculture

ILRI scientist Silvia Alonso presents at the 6th All Africa Conference on Animal Agriculture held at Nairobi, Kenya on 27-30 October 2014 (photo credit: ILRI/Tezira Lore).

Scientists from the International Livestock Research Institute (ILRI) yesterday (28 Oct 2014) presented some of their recent research findings from studies on animal health and food safety in East Africa at the 6th All Africa Conference on Animal Agriculture. The conference is being held from 27 to 30 October 2014 at the Kenyatta International Convention Centre in Nairobi, Kenya.

Some 300 participants from all over Africa and beyond are attending the conference whose theme is Africa’s animal agriculture: Macro-trends and future opportunities. The five conference sub-themes are:

• Youth: The future hope?
• Which way for smallholder production systems?
• Pastoral systems: Options for tomorrow
• Market access: Opportunities for enhanced access to local, regional and global markets
• Africa’s human capacity challenge for animal agriculture: Which way now?

Silvia Alonso, a postdoctoral scientist with ILRI’s Food Safety and Zoonoses program presented the following two papers:

• Smallholder pig producers and their pork consumption practices in three districts in Uganda (presented on behalf of lead author Kristina Roesel, an ILRI graduate fellow at Freie Universitaet Berlin and coordinator of the Safe Food, Fair Food project)
• Vaccination as a way forward? A case study on how a poultry vaccination intervention influences poultry keeping in Kenya (presented on behalf of lead author Johanna Lindahl, an ILRI postdoctoral scientist)

Results from a study on Kenyan milk consumers’ behaviour and perceptions of aflatoxin were also presented. This study was a joint output of the CGIAR Research Program on Agriculture for Nutrition and Health and the CGIAR Research Program on Policies, Institutions and Markets.

Additionally, the following ILRI posters on smallholder dairying in Tanzania and pastoralism in Kenya and Tanzania featured in the poster session:

• Smallholder dairy farming in Tanzania: Farming practices, and animal health and public health challenges and opportunities
• Pastoralism in Kenya and Tanzania: Challenges and opportunities in animal health and food security
• Creating novel approaches to mitigate aflatoxin risk in food and feed with lactic acid bacteria – mold growth inhibition and aflatoxin binding

 

Posters by projects in ILRI’s Food Safety and Zoonoses program featured at the 6th All Africa Conference on Animal Agriculture held at Nairobi, Kenya on 27-30 October 2014 (photo credit: ILRI/Tezira Lore).