Azolla is a free floating aquatic fern of the family Azollaceae and order Pteridophyta. They are rich in protein, minerals, vitamins etc and are an emerging unconventional feed and protein supplement for animals like ruminants, pigs, poultry and fish. Azolla is easy to cultivate and when fed to animals reduces cost on feed which is one of the highest input or cost in any livestock and poultry rearing. It is reported by various researchers that inclusion of azolla in animal diet promotes feed intake, body weight gain and improves the overall health as azolla contains growth promoters and is easily digested by the animals. Azolla is also grown along with paddy as it acts as bio-fertilizers for wetland paddy thereby increasing the yield of paddy by more than 20%. It can be found growing in pond, canal, river and other water sources. Dry flakes of azolla is used as feed for livestock and poultry while fresh azolla is used as feed for fish. For culture of azolla, the pH of the soil should be 4.5 to 7.0 (tolerable pH 3.5 to 10.0). The temperature favorable for its growth ranges from 18 to 28º C. For culture of azolla, firstly a trench (e.g. 6.0x1.0x.02m) should be made preferably in a shade area avoiding direct sunlight. Silpauline sheet is than spread uniformly in all corners of the pit. The azolla should always be reared in partial shade as it grows better under partial shade. Maintain 10 cm water level and the water should be changed after every 20 to 25 days. Add dry FYM (Farm Yard Manure) and DAP (Di Ammonium Phosphate) so to avoid turning it reddish. Harvest when tank is full. It is estimated that 35 to 40 tons of azolla on dry weight basis can be harvested per hectare per year.
EFFECTS OF FEEDING AZOLLA TO RUMINANTS
Azolla is fed to milch animals like cows and buffalos in about 1.5 to 2 kg along with concentrate feed in 1:1 ratio with green fodder (ad lib) will increase milk by 20.96% in cows and by 16.9% in buffalo. Increase in milk in liters and fat in percentage for cow is 1 to 1.5 liters and 4.4 to 4.7 percent respectively and for buffalo is 1 to 1.4 liters and 6.2 to 6.9 percent respectively. Feeding of azolla reduces the requirements of commercial feed by about 20 to 25 % and thereby saves money for the farmers. Azolla can be used as a conventional feed upto 35% in lactating cow. In growing calves increase in growth rate by 9% is obtained when azolla is given at 60 gram per animal per day. The benefits of feeding azolla to ruminants goes listless as it increase the milk production, milk fat percentage, reduce in buying commercial feeds, improves in growth of calves, reduces in milk production cost when fed to calves, improves hair coat and keeping the animal active.
EFFECTS OF FEEDING AZOLLA TO NON-RUMINANTS
Azolla feeding in broiler chicken improves in weight gain and increases egg production in layers. Dried azolla at the rate of 5% when fed to broilers, improves feed intake, higher body weight gain and feed conversion efficiency of 2.06 at 2 to 6 weeks of age. Research findings indicates that azolla can be used upto 15% in their diet will not affect their feed consumption. The cost of broiler production will be significantly low if azolla is supplemented @ 5%. They can be fed upto 10% of basal diet in Pekin broiler ducks.
Azolla can also be fed to sheep, goats, pigs and rabbits with no adverse affects on their performances. Azolla cultivation with paddy and fish is said to have increased the rice production by 20% and fish production by 30% respectively.
CONCLUSION
Azolla can be fed both to ruminants and non ruminants as an ideal feed. In paddy field they are used as biofertilizers for wet land paddy. It has become a popular feed item and widely cultivated in countries like China, Vietnam and the Philippines while our country is in developing stage. Azolla can serve our purpose of feeding animals and poultry in near future along with techniques like processing and preservation like hay and silage for lean periods. They are given at the rate of 1.5 to 2.0 kg to adult cow , buffalo and bullock, 1.5 to 2.0 kg to pigs, 300 to 500 grams to goats, 20 to 30 gram to layers/broilers and 100 gram to rabbits.
Article submitted by Krishi Vigyan Kendra, Animal Science Division, Tuensang
