Azolla and Duckweed as Poultry Feed in Ghana

A green skin on the pond in three weeks

A shallow tank of still water in the right sun will be covered in green within three weeks. Some farmers see that and count free feed. Others see a mosquito nursery and a smell. Both are right. The plant is the same in either case, and the difference is what you do with it next.

This article is about using azolla and duckweed as a feed for ducks and chickens in Ghana. We will cover what the plants are, how much protein and water they carry, how to grow and dry them, and how to bring them into a ration without causing trouble.

What azolla and duckweed are, in plain terms

Azolla is a small floating fern. Its leaves hold a blue-green cyanobacterium that takes nitrogen from the air and makes it available to the plant. That partnership is why azolla grows well in poor water and why farmers in several tropical countries have used it as a green manure and as a feed.

Duckweed is the common name for a family of tiny floating plants, often in the genus Lemna. Each frond is only a few millimetres across, and in warm, still, nutrient-rich water the mat can double in size in a short time. Both plants cover the surface of a tank quickly, and both can be harvested by skimming with a net or a sieve.

The two are not the same, and they behave differently. Their fibre, growth rate and handling differ, and the results depend on species and water. Duckweed is generally easier to skim. Many farms that try one end up keeping both in separate tanks, so they can rotate the harvest.

How much protein is in them, and how much is water

The figures that matter are the dry matter and the protein in the dry matter, not the fresh weight. Fresh azolla and duckweed are very wet. The table gives planning figures from the range reported in the literature. Your own material will vary with species, water, light and how much fertiliser the tank gets, so measure a sample before you rely on it.

The arithmetic is blunt. A kilo of fresh plant may hold only 40 to 80 grams of dry matter. If the protein is about a quarter of that dry matter, one kilo of fresh plant gives the bird roughly 10 to 20 grams of protein. Plenty of farmers weigh a bucket of plants and feel rich. The bird is getting a small share of what the bucket appears to hold.

Fresh or dried: the water problem

Feeding fresh is the simplest route, especially for ducks on a pond. The plants are palatable and the birds eat them quickly. For chickens, fresh material has to be chopped or spread on a clean floor, and it wets the litter if too much goes down at once. Anything left in the sun for a day starts to rot in the heat.

Drying solves most of that. Spread the harvest in a thin layer on a mesh or a clean sack, in shade or in open air with good airflow, and turn it several times a day. In dry weather, it can take a day or two. In the rains, a shaded rack with air moving underneath is the only reliable method, and even then the material needs to be checked every morning.

Dried material must be fully dry before storage. Put it in a sealed container, away from the floor and walls, and check it weekly for a sour or musty smell. Mould in the dried meal is a feed safety problem, and it spreads quickly in the humid months, especially in the coastal and forest-belt parts of the country.

Setting up a small tank in Ghana's climate

A tank for azolla or duckweed does not need to be large. A shallow tray or a low concrete or plastic tank, about 20 to 30 centimetres deep, is enough for a small flock. Put it where it gets good light but not the full afternoon sun, since water over about 35 degrees slows the growth and can scorch the plants at the edges. A shade net over part of the tank is a practical fix.

Use clean water. Rainwater from a clean roof, a borehole or treated tap water are all reasonable choices. Stagnant water from a gutter, a drain or a ditch carries whatever is upstream of it. Add a little well-composted manure, a few handfuls per tank, to feed the plants. Fresh manure brings in pathogens and ammonia, and it can foul the water faster than the plants can use it.

Growth slows in the harmattan, when nights turn cool and dust hangs in the air. Plan for a smaller harvest from December to February, and do not build a flock's feed plan around the peak months of the rains. Standing water attracts mosquitoes whatever plant is growing in it, so keep the edges clean and check the tank weekly.

How many birds one tank can feed

The planning sum starts with the share you want in the ration. Say you want 5 per cent of the ration's dry matter to come from dried azolla, and a laying hen eats about 110 grams of feed a day. That is 5.5 grams of dry matter per bird per day. If the fresh material is 8 per cent dry matter, the hen needs about 69 grams of fresh plant each day. The table scales that up.

The 8 per cent dry matter figure is a planning number, not a measurement. Weigh one full day's harvest, dry a sample to constant weight, and calculate your own figure. Then check whether the tank can actually supply the daily weight. A tank that looks full may still give only a few kilos a day, depending on its surface, the light and the season.

Which birds take it well

Ducks are the easiest case. They eat fresh plants readily, filter the water, and handle a moist diet with fewer problems than chickens. A duck flock that has access to a clean pond or a tank with a little azolla will usually take it without fuss. Our duck farming guide for Ghana covers the rest of their management.

Chickens are more selective and more sensitive to the balance of the ration. Trials in tropical poultry have used dried azolla and duckweed at low shares in layer and broiler diets, often well under a tenth of the ration. Treat that as a ceiling to test, not a target to aim for. Above it, the extra fibre and the lower energy start to show in intake and weight.

Broilers need energy and amino acids on a fixed schedule, so use a low share and keep an eye on their weight against the chart. Layers need calcium and energy as well as protein, so a plant-based share should sit inside a complete layer ration rather than replace one of its parts.

Safety: water, snails, parasites and metals

Azolla and duckweed take up what is in the water. That is useful when the water is clean and a problem when it is not. Heavy metals and pathogens from sewage, drains, slaughter waste or a polluted ditch can end up in the plant, and then in the bird. Harvest only from water you would be willing to drink yourself, and keep the tank well away from waste outlets.

Snails and worm larvae can share the tank with the plants. A harvest that is not washed can bring snails, and some snails carry the parasites that cause worm problems in birds. Rinse the fresh material well, pick out visible snails before feeding, and keep to a regular worm control plan that your vet advises.

Our guide to worms and deworming chickens in Ghana covers the signs to look for, and the worm plan belongs to your vet, not to the feed.

Introducing it to the ration gradually

A bird that has never seen azolla will sometimes ignore it, and a bird that has had too much at once may go off its normal feed. Introduce it in steps and watch the flock at each one.

1. Week one: offer a small share, about 2 per cent of the dry matter, mixed into the normal feed or offered fresh alongside it.
2. Week two: if droppings are normal and intake is steady, move to about 5 per cent.
3. Week three onward: hold at the share that works, and do not raise it again without a reason.
4. At each step, record how much feed went in, how much was left, and any change in droppings or water intake.

Make one change at a time. If you start azolla in the same week as a new feed or a new batch of chicks, you will not know which change caused a problem.

Where azolla and duckweed do not fit

The plants are not the answer for every farm. If your water is poor, your tank is near a waste outlet, or the only water you have is seasonal, the cost of getting the plants clean and the risk of contamination may outweigh the benefit. In that case, buying a known protein is cheaper and safer.

They also do not fit a farm that is trying to push broilers hard. A broiler on a fixed growth plan depends on steady intake, and a feed that dilutes its energy will slow the flock at the point where it matters. Keep the plants for ducks, for small layer flocks, and for free-range birds on a supplement. Our guide to kitchen scraps and forage for chickens covers the other free feeds that suit a free-range flock.

Compare the cost of the plant protein with a bag of soya or fishmeal, measured per kilo of usable protein, not per bucket. Our guide to cheaper poultry feed alternatives in Ghana sets out the sums, and the moringa leaf meal article uses the same approach for another plant feed.

Is pond weed worth the effort here?

We hatch and import chicks, and we do not sell feed or water plants. We do see what happens when a farmer adds a new feed to a flock that is still settling, and the usual cause of trouble is adding too much at once, not the plant itself. A flock that starts well on a balanced ration can take a small share of a new feed without fuss.

If you are planning a flock around a feed plan like this, start from our day-old chicks page to choose the line, and read our duck guide if ducks are part of the plan. Our questions page covers ordering and collection, and you can place an order through our order form, and our team can be reached on WhatsApp at +233 24 915 1503 with questions about the chicks.

A checklist before you feed azolla or duckweed

1. Confirm the water source is clean and away from drains, waste outlets and livestock wash areas.
2. Set the tank in shade, with a shade net over part of the surface, and check its water weekly.
3. Weigh one full day's harvest and dry a sample to find your own dry matter figure.
4. Dry the harvest in thin layers, out of direct sun, and store it sealed and dry.
5. Rinse fresh material and remove snails before feeding it.
6. Introduce it in steps, starting at a small share, and record intake and droppings at each step.
7. Keep a balanced ration in place, and check the flock's weight and egg records against the plan.

Questions farmers ask