9 June 2017, Nairobi – The International Livestock Research Institute (ILRI) has launched an instructional video that teaches dairy farmers how to make sweetpotato vine silage. The video titled ‘Sweetpotato Vine Silage: An instructional video for dairy farmers’ was developed by the Mazingira Centre —an environmental research and education facility—based at ILRI Nairobi.
The instructional video on how to prepare sweetpotato vine silage for dairy feeding was produced under a project, in Kenya, implemented by ILRI’s Mazingira Centre on Innovative Feeding Approaches for Dairy Farmers, implemented under a Green Innovation Centres (GIAE) program funded by the German Corporation for International Cooperation (GIZ). The original design and development of the Sweet Potato Vine Silage (SPVS) technology was carried out by the International Potato Center (CIP) with assistance from the University of Nairobi. The video was shot at the climate smart villages of the CGIAR research program on Climate Change, Agriculture and Food Security, in Nyando village, Kisumu, Kenya.
View the half-hour instructional video
Dairy production is an important sub-sector in Kenya, accounting for eight percent of the GDP. However, it is far from reaching its full potential. The sector is driven by a large proportion of smallholder farmers, who face many constraints related to feed. Often, they do not understand the nutritional requirements of their dairy animals well enough, neither do they know how to meet these needs. This leads to low productivity.
Since early 2016, staff of Mazingira Centre have been implementing intensive four-week training sessions on dairy production for smallholders. One of the training modules focuses on dairy feeding and feed management and emphasises on how to make and preserve sweetpotato silage. To date, more than 170 farmers from Kisumu, Kakamega, Siaya, Bungoma and Migori counties of western Kenya have been trained.
Speaking at the launch, John Goopy, an ILRI scientist leading this project, explained that over the course of one year, the farmers that they trained had gone ahead and trained an additional 1,200 small-scale farmers on sweetpotato vine silage technology.
Speaking on behalf of CIP, Sammy Agili, an agronomist who worked on the pilot project, explained that CIP had worked with Kenya Agriculture and Livestock Research Organisation (KALRO) to develop dual purpose varieties that could be used for fodder and root production, and that the technology had been improved to improve drainage of moisture and ensure that the silage kept for a longer period.
The potential for sweetpotato silage for improving dairy feeds
Vines and small roots unsuitable for human consumption are rich in protein (vines) and energy (roots) and can be used for improvement of locally available feeds such as poor quality roughages. With a root/vine ration of between 1.5 and 2.0, vines can be cut twice during the growth period of the crop without compromising the root yield.
During the dry season most grass feed are rich in fibre (cellulose and lignins) and poor in sugar and protein. Providing livestock with energy and protein feeds such as that obtained from sweetpotato vines can help livestock make use of dry season feeds. Sweetpotato vines contain up to 19% crude protein. Both vines and roots can be conserved as silage to be used during times of feed scarcity.
To make sweetpotato silage, chopped leaves, vines and roots are combined with Napier or other grass and wheat bran in correct proportions. Molasses is added to the mixture to aid in fermentation and to increase the nutrient content. The fermentation process takes 30 days.
Farmers have been taught to properly preserve sweetpotato silage in a special plastic tube silo which is constructed using locally available material. They must ensure that the silage is completely drained of water, and is not exposed to air. If preserved properly, sweetpotato silage can last up to 400 days.
Silage has long been in use in Asia, but in sub-Saharan Africa, it started with CIP’s Sweetpotato Action for Security and Health in Africa (SASHA) in 2009. In Uganda, the RTB-ENDURE project developed an innovative business model to promote and commecricalize sweetpotato silage for small-scale pig farmers. Their trials found that the best return, in terms of weight gain value per kg feed was 60% silage, 40% maize-soybean-meal, as long as cost of silage remained under Ush. 600 per kilogram.
Developing varieties for human and livestock consumption at KALRO
Having recognized the potential of sweetpotato for both human and livestock use, the Kenya Agricultural and Livestock Research Organization (KALRO) has been working together with the International Potato Center (CIP) to develop dual purpose varieties that can easily be incorporated in smallholder farming systems. Three promising varieties have been identified, Shock5, SilkLow6 and New Kawogo14. While sweetpotato has traditionally been produced in low altitude areas, some varieties have been released for high altitutde areas. These include Naspot1, KEN23, KEN36 and Gwerri.
The launch of this instructional video will help to complement training and extension services provided to farmers. It will help to operationalize the findings of years of research on sweetpotato silage, and increase the productivity of dairy animals.
View the summarised version