Azolla-As Livestock Feed

About Azolla

• Azolla is a aquatic floating fern which resembles as algae.
• The fern appears as a green mat over water.
• Normally azolla is grown in paddy fields or shallow water bodies.
• Azolla multiplies very rapidly.

Azolla as fodder/ feed

• Rich in proteins, essential amino acids, vitamins (vitamin A, vitamin B12 and Beta- Carotene), growth promoter intermediaries and minerals like calcium, phosphorous, potassium, ferrous, copper, magnesium
• Dry weight basis, it contains 25 – 35 percent protein, 10 – 15 percent minerals and 7 – 10 percent of amino acids, bio-active substances and bio-polymers.
• Livestock easily digest it, owing to its high protein and low lignin content.
• Azolla can be mixed with concentrates or can be given directly to livestock
• Can also be fed to poultry, sheep, goats, pigs and rabbits.

Nutrition wise comparison of Azolla with other fodder

Azolla Production

• The soil in the area is first cleared of weeds and leveled.
• Bricks are lined horizontally in a rectangular fashion.
• A UV stabilized silpauline sheet of 2mX2m size is uniformly spread over the bricks in such a way as to cover the margin of the rectangle made by the bricks.
• 10cm standing water are maintained in pit.
• 10-15 kg of sieved soil, 2 kg cow dung slurry and 30 g of Super Phosphate mixed in 10 liters of water, is mixed in water in pit.
• About 0.5-1kg of pure azolla culture seed is spread uniformly over the water, after mild stirring of soil and water in the azolla bed.
• Fresh water    should   be   sprinkled   over the       azolla    immediately after inoculation to make the azolla plants upright.
• In a week’s time, the azolla spreads all over the bed and develops a thick mat like appearance.
• A mixture of 20 g of Super Phosphate and about 1 kg of cow dung should be added once in 5 days in order to maintain rapid multiplication.
• A micronutrient mix containing magnesium, iron, copper, sulphur etc., can also be added at weekly intervals to enhance the mineral content of azolla.
• About 5 kg of bed soil should be replaced with fresh soil, once in 30 days, to avoid nitrogen build up and prevent micro-nutrient deficiency.
• 25 to 30 percent of the water also needs to be replaced with fresh water, once every 10 days, to prevent nitrogen build up in the bed.
• The bed should be cleaned, the water and soil replaced and new azolla inoculated once every six months.
• A fresh bed has to be prepared and inoculated with pure culture of azolla, when contaminated by pest and diseases.

Harvesting

• Will grow rapidly and fill the pit within 10 – 15 From then on, 500 – 600 g of azolla can be harvested daily.
• Can be done every day from the15th day onwards with the help of a plastic sieve or tray with holes at the bottom.
• The harvested azolla should be washed in fresh water to get rid of the cow dung smell.

Alternative Inputs

• Fresh biogas slurry may also be used.
• Waste water from bathroom and cattle shed can also be used to fill the pit. In areas where there is a problem of fresh water availability, the water left after washing clothes (after the second rinsing) can also be used.

Environmental factors for the growth

• Temperature 20°C – 28°C
• Light 50% full sunlight
• Relative Humidity 65 – 80%
• Water (standing in the tank) 5 – 12 cm
• pH 4-7.5

Points to be noted during cultivation of azolla

• Washing in a net will be useful as it will allow small plantlets to get out, and they can be poured back in to the pond.
• Care should be taken to retain the temperature below 25°
• Shade nets can be used to cut the light intensity.
• The azolla biomass should be removed daily to avoid over crowding.

Precaution to be adopted

• Maintenance of pure culture free from contamination is essential for good yield.
• Azolla should be harvested regularly to avoid overcrowding.
• Temperature is an important factor for good growth. It should be around 35 degrees Celsius. The fodder plot is to be covered with a plastic sheet in cold regions so as to reduce the impact of cold weather.