chicken notes: azolla

Tom of Uluwehi farm wrote to say "Azolla, a fresh water seaweed has been used in India as sole rationing for chickens."
CTAHR page on Azolla as Green Manure has good info on Azolla's optimal growing conditions
- it actually does not like full sun. overcast skies or partial shade are better
- says A. filiculoides is the species most commonly found in Hawai`i
from Biotechnology of Biofertilizers: "growth rate of Azolla is very rapid so much so that it doubles its weight in a mere 2-3 days."
It can assimilate atmospheric nitrogen owing to a symbiosis with nitrogen-fixing cyanobacteria (blue green algae) living in the cavities located at the lower side of upper (dorsal) lobes of leaf.
The plant is green when conditions are perfect, tending towards yellow/orange/red when not perfect, e.g. water too warm, missing nutrients, wrong pH, etc. So, the color can't be used to identify the species, it is related only to how well the plant is growing.
Sounds like a great plant to try growing and feeding to chickens.
08.05.03, got some Azolla from the Uluwehi farm, brought it home to try.
It looks somewhat different than the other Azolla species pictures on the web. A snapshot:
It looks closest to A. pinnata.

Azolla: a sustainable feed for livestock, India
- describes in good detail exactly how to grow and harvest Azolla in a shallow man-made body of water. It says "Feeding azolla to poultry improves the weight of broiler chickens and increases the egg production of layers." The only input is some manure and phosphate.
Azolla (Azolla pinnata) as a Feed Ingredient in Broiler Ration, International Journal of Poultry Science, 2002, Bangladesh
- Tested different amounts of 'Azolla meal' in the feed - 5%, 10%, 15%
- At 5%, the broilers actually grew better than with conventional feed. At 10% and 15%, results were about the same as with conventional feed, a little less body weight. The giblets were a little bigger and the abdominal fat was a little less.
- says Azolla's total protein is 25-30%.
Package of Practice for Azolla has a lot of info including nutrition.
- "Dry Azolla flakes can be used as poultry feed and green Azolla is also a good feed for fishes."
There doesn't seem to be any research on how much azolla you can feed to layers/broilers and still maintain health and productivity. Would 50% or more be too much? Could the nutrition profile be balanced with specific other feed inputs?

2008 blog entries Azolla as chicken feed (May) and Azolla update (July) describe our experiences.
We have only a very small area of water to test with.
The chicken do eat it fresh, although not enthusiastically.
Any more serious effort would involve setting up a large water surface area - troughs, or some kind of pond.

"There are approximately 70 species, subspecies, varieties, forms, and cultivars in this genus."

species / wikipedia link	pictures	descriptions
Azolla caroliniana		Native to the Americas. "Of commercial importance in cultivation in Asia as a bio-fertilizer, valued for its nitrogen-fixing ability, [..] harvested fronds are also used as a food for fish and poultry."
Azolla filiculoides	(with duckweed)	"for use as green manure" "species most commonly found in Hawai`i"
Azolla japonica
Azolla mexicana		"often mixed in with duckweed."
Azolla microphylla	(with filiculoides)	"a natural source of protein, as a main component in food for tilapia" In one study of Azolla species, "gave highest biomass production and relative growth rate."
Azolla nilotica	no pictures found online	reportedly very large fronds
Azolla pinnata		"Azolla pinnata has been used for centuries in Southeast Asia as a fertilizer in rice production." Has a huge native range, all the way from Africa to Japan and Australia.