I am a zero-grazing cattle-keeper with three cows. However, I also grow potatoes for sale. How can I turn these potato vines into livestock feeds?
It is true that sweet potato vines can be prepared as feed for livestock. However, one major negative attribute of sweet potato residues is that although they are a good source of energy (roots) and protein (vines), they are highly perishable. There is also a lot of wastage of sweet potato residues during a period of abundance.
Over 30% of sweet potato roots and vines of the total produced annually are left in the fields. These residues dry and lose their nutritional value.
Turning them into silage is, therefore, the best option. Silage-making ensures off-season availability of feeds for at least three months from materials which would otherwise go to waste due to high moisture content. Ensiling removes the risk of toxicity due to anti-nutritional factors and harmful micro-organisms. It degrades some unpalatable substances in the feeds and enhances their palatability.
Well-made silage is wholesome and nutritious feed for all cattle and pigs. Silage has high protein content and digestibility, which makes it an excellent complement to grass feeds.
Silage-making ensures more economical use of plants, with high yield of green mass. It also prevents nutrient loss, which in standard grass hay production may amount to 30% of the dry matter (in silage, it is usually below 10%).
Sweet potato silage-making using plastic tube bags
Plastic tube bags and drums are an economical alternative to traditional silage storage systems, such as pits and silos.
A silo is a structure for storing bulk materials. Silos are used in agriculture to store grain or fermented feeds known as silage.
Ensiling in a bag and a drum avoids the hard work of having to remove silage from the pit in which it is buried to ferment.
How to make sweet potato silage
Sweet potato silage can be made using chopped vines or combined chopped vines mixed with roots of non-commercial value (at a ratio of 70:30). Select a strong plastic sheet with high density (1.5m width, gauge 600 to 800 mm) to make plastic tube silage bags.
High rather than low-density plastic reduces the risk of tearing. Imported plastic tube silage bags are now available in Kampala.
Plastic fertiliser bags make good silos. Plastic drums are expensive, but can be used for many years and are not damaged by rodents.