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Azolla is an aquatic fern, which is cultivated in many countries as the only crop or mixed with rice. Recently, inGillancultivating and production of this plant is expanding. One aspect of utilaztion of azolla is that, it can be used as a feed source in animal and poultry nutrition.To take into consideration nutritive value of azolla and scrcity of feed in Iran, it was decided to use this plant as a feed stuff in ration of lactating cow, and to stddy its effects on milk yield and its composition
In this study,using a balance—change over design, sixteen lactating Holstein cows with similar condition were selected and allocated into four blocks as a 4x4 Latin square design. The cows were individualy fed four rations including corn foddere, silage and concentrates. The concentrates contained O.O%(A), 15%(B), 25%(C)and35%(D)Azolla. Concentrates were formulated to isocaloric and isonitrogeneous. In the course of study, the cows were milked twice daily and milk weights were recorded. Milk samples were collected twice weekly in each period. Milk samples were analyzed for fat, crude protein (NX 6.38),ash, and total solids. All data were analyzed ststistically.
The obtained results indicated that, the difference, between milk yeilds (Kg) and fat percentages: 12.09. 3.3,11.9, 3.12, 12.5, 3.7 and 11. 79, 3.83, for rations A,B,C and D respectively, were not statistically significant (P< 0.05). This trend also was true for the amount of protein, ash, lactose and total solids. During the course of this research, there was no sign of concentrate unpalatability, metabolic disorder or any illness.
In summary the result of this study, suggestss that it is possible to use Azolla as feed ingredient,up to 35% of ration of lactating cow.