The piglets look happy and healthy as they run towards us. They squeal and knock each other as they try to squeeze through the gaps in the gate to get closer. Today, we are visiting the satellite research offices of the National Agricultural Research Organization (NARO) in Central District, Uganda. The site is high up on a hill overlooking lush farmland. We are here to visit with project staff who are leading the research on using sweetpotato silage (fermented and high moisture fodder, usually made from grass crops) as pig feed.

It is a picturesque site and a great example of a project based on strong partnerships. Hosted at NARO, led by CGIAR centers and with strong support from local NGOs and private sector organizations this is a truly blended research initiative.

The project is investigating options for sweetpotato silage making and supplementation for small holder pig farmers in Uganda. Research is on potential business models to produce, conserve and commercialize sweetpotato-based feed and the team expects the research to transform production and utilization of sweetpotato vines and roots to lessen the constraint of livestock feed shortages for smallholder farmers in the country.

Sweetpotato vines: a nutritious and affordable option for pig feed in Uganda

"Feeding is one of the main production constraints for smallholder pig farmers and so we are looking at ways to help these farmers produce nutritious and affordable feed options for their pigs," says Peter Lule, the research technician with the International Livestock Research Institute (ILRI) working in the Central Region of Uganda.

"Sweetpotato silage is very nutritious - it is high in protein which is one of the reasons that we work with it." explains Gerald Kyalo, the Principal Investigator for the project. "If you want to maximize growth of the pigs then you must get the right mixture. We are focusing on supplementing the silage with legumes, which contain a lot of protein, and also with cassava and maize bran which contain carbohydrates." Research is currently being conducted to determine the best dual purpose sweetpotato varieties and harvesting regimes that will ensure an optimal balance between production of roots to sell and vines for fodder.

Addressing scarcity and bridging the feeding gap

Production constraints for pig farmers are caused by the seasonality of sweetpotato, the high cost and poor quality of readymade feeds and an often limited knowledge of supplementation strategies. To get by, farmers will often use crop residues, grasses, weeds and kitchen leftovers to feed their animals. "Sweetpotato vines are often used as fodder for animals. However, they are highly seasonal and perishable, so we are doing research so that we can teach farmers how to make silage from the vines, which can be preserved. If you combine this with strategic supplementation, then it becomes an easy and affordable feed option for farmers," explains Peter.

"During the rainy season there is a lot of sweetpotato vines available for silage. During the dry season there is scarcity. We want to find a way to bridge that gap so that farmers can access nutritious sweetpotato feed for their pigs all year round." Peter tells me as we wander through the pig pens which are full with large mother pigs and lots of piglets, each as energetic as the next.

"The project grew out of research work done in 2012-13 - our first step is to develop evidence based information that sweetpotato silage is a nutritious and affordable option for farmers to give to their pigs. We want to make silage using ingredients which are common here in Uganda and which farmers can easily find. “ explains Gerald.

Collaboration the key to success

The project has four key components: investigate options for silage making and supplementation; identify models for organization of value chain actors ; strengthen links between pig farmers and sweetpotato traders; and build business capacity for profitable silage making and pig raising. To achieve these goals collaboration is key.

"ILRI and CIP are leading the research component. We are focused on assessing the current diets of pigs here in Uganda and are carrying out on-station feeding trials in collaboration with NARO to assess how to supplement sweetpotato into animal feed and to test the health of pigs when eating this type of silage," explains Peter. "It is a great way to combine our expertise - CIP knows sweetpotato and ILRI knows livestock."

"When you have a project like this, you cannot implement it alone - you need local partners in the country you are working in. NARO is the lead research partner - they have the mandate to conduct all agricultural research in Uganda and so our collaboration with them is very important. In particular, we value the strong relationships they have with farmers which is vital to our work. We also can't underestimate the role of private sector in developing a business proposition for silage. We are working closely with a range of private enterprises like PPM - Pig Production Ltd. They trade in pigs and so provide invaluable knowledge about the pig value chain in Uganda," explains Gerald.

Is there a business case for sweetpotato silage?

In Uganda, quality commercial pig feeds are expensive. Locally available feeds are seasonal in nature and often of poor quality, so with feed accounting for about 62% of the total production costs in pig farming this is a key issue for smallholder farmers. "We will investigate opportunities to produce sweetpotato silage as a business model. We are taking time to review the current markets: what feed is sold, at what price, when farmers make their own or purchase and for how much," Peter explains to us.

The team will establish a business case for selling sweetpotato silage in the Uganda market and increase profitability. Over the term of the project the aim is to have 5% of pilot farmers selling sweetpotato silage, making 20% savings on purchased pig feed cost and seeing a 20% average increase in pigs’ weight gain. In addition, the team want to see the initial adoption of the technology in chosen sites. The aim is to have 50 additional male and female farmers around the demonstration centers feeding pigs with sweetpotato silage and one farmer/entrepreneur in each project site starting a silage making business.

So far project staff have adapted and developed protocols to guide silage making and pig feed supplementation. Ten treatments have been tested on sweetpotato silage and supplementation regimes and organoleptic results have been generated. Analysis is being carried out on the samples to assess the nutritive value of each treatment. Trials on dual purpose varieties that would best fit within farming systems in certain areas are also underway, while 16 pilot farmers (50% female) who will host the on-farm feeding trials have been profiled and have established sweetpotato gardens.

Practical application for farmers

The project leaders are focused on developing technical capacity with direct application for farmers, Gerald tells me: "We conduct research so we can make recommendations to our farmers - how do you supplement it? What ingredients are needed? Should we include cassava, red beans, sweetpotato and if so at what ratio? Farmers want to maximisze the growth and nutrition of the pigs so we need to know these things. We think there is a good business case for silage but we need to prove this before farmers will be convinced."

"I think this is really accessible to farmers. It is low cost technology which harnesses products that farmers already have on hand - sweetpotato and pigs. Making the silage is also simple and goes a long way. For two to three pigs, one farmer can easily make enough silage on farm and by hand. If you have a large number of pigs, then we have another method that we are teaching to make large quantities," explains Gerald. "We need to make sure this is something that farmers can produce and afford. It needs to be accessible."

This is also a way to streamline practices for farmers and decrease waste on the farm. The research team is looking to decrease post-harvest losses, aiming for a 50% average reduction in the amount of wasted vines by pilot farmers, as well as utilization of at least 20% of non-marketable roots for silage. The team is also aiming to allow pilot farmers to feed pigs on silage for at least 3 months in a year.

Increasing farmer capacity and developing platforms for improved impact

An important component is to increase capacity of farmers. So far 30 extension staff and model farmers have been trained as trainers in silage making and a number of pilot farmers in Masaka and Kamuli have been trained. Existing multi-stakeholder pig platforms have been leveraged with the aim of bringing together current members and selected project partners which will allow interested actors to keep abreast of pertinent issues.

Three Master’s students are conducting research to complement project outputs and strengthening capacity of pilot farmers and youth in silage making and feeding is a priority. Farmer demonstration centers will soon be established and equipped so that silage making can be delivered to a wider area. Silage making manuals in English and a local language have also been developed as well as various communication material.

"We have conducted trainings on silage making for about 40 participants. We trained farmers on the importance of silage, how to utilize silage and what they could sell if they made silage for themselves. The farmers were very interested," explains Gerald.

Improving the place for female farmers in the pig value chain

Understanding gender dynamics in value chains is critical to design of strategies that address the needs of both male and female actors. This enables faster technology adoption and more equitable action for reduction of post-harvest losses, increased utility and benefits for women and men

"In Uganda, women are often in charge of growing sweetpotato. They are also involved in pig keeping. So we think there are good opportunities to improve the way women participate in the pig value chain" Gerald says.

In research thus far, it has become apparent that women generally had less access to market information, alternative markets and post-harvest technologies. They generally advocated for simple storage technologies like pit stores and simple technology like silage production. To avoid losses, female traders procured stock which could be sold in three days, so finding a way to prolong the shelf life of sweetpotato vines as animal feed would be very beneficial.

"A key outcome from this project is to see a more equitable distribution of benefits between men and women in the pilot households that we work with. We want to see at least 20% of women involved in more profitable nodes of the chain and at least 30% of women perceiving greater control over income," says Gerald

Before we leave I head back towards the buildings to say farewell to the staff and to get a last glimpse of the view of the beautiful farmland surrounding the site. From where I stand I can see the pigs who seem happily distracted running about their pens and in the far distance I can see the green of the sweetpotato fields spreading out below the station. From up here the two appear to go very well together...

Why this research is important

Roots, Tubers and Bananas crops are an important source of food and income in most developing countries. In Sub Saharan Africa, the crops are a major staple providing 20% of calorific requirements and constituting nearly two thirds of per capita food production. However, their full potential to contribute towards food and income security has not yet been realized due to a number of challenges, including bulkiness and high perishability of the crops, poor postharvest management and lack of storage and processing facilities.

The team

The project is led by the International Potato Center (CIP) and implemented in collaboration with International Livestock Research Institute (ILRI), the National Agricultural Research Organization (NARO), Makerere University, Uganda Martyrs University, Volunteer Efforts for Development Concerns (VEDCO), Coalition for Health, Agriculture and Income Networks (CHAIN)-Uganda, Pig Production and Marketing Ltd (PPM) and farmer organizations.

Expanding utilization of roots, tubers and bananas and reducing their postharvest losses

RTB-ENDURE is a 3 year project (2014-2016) implemented by the CGIAR Research Program on Roots, Tubers and Bananas which aims at addressing these challenges and opportunities. The project is funded by the European Union and technical support of IFAD.

Words & Images: Sara Quinn, Regional Communications Specialist, International Potato Center