This experiment was conducted to determine the changes in chemical compositions of alfalfa dried with two different way in the drying unit supported with the solar energy and dried traditionally on field and the effects of those alfalfa on nutrient digestibility, ruminal fermentation and feedlot performance. For this purpose, 18 Akkaraman lambs were allocated to three groups.

Treatment groups consisted of alfalfa dried with different methods were as follows: Alfalfa cut and dried in the drying unit at the harvested day ( K Group), alfalfa wilted for 24 h and dried in the drying unit ( P Group ) and alfalfa dried traditionally on field ( T Group).

The digestibility of nutrients in groups were 62.11, 61.28 and 55.01 % for dry matter, 73.50, 72.50 and 71.08 % for crude protein, 35.38, 35.24 and 34.30 % for ether extract, 45.81, 45.62 and 42.80 % for crude fiber, 67.95, 67.80 and 65.71 % for nitrogen free extract, 45.53, 45.48 and 43.62 % for NDF, 45.08, 45.11 and 43.21 % for ADF, 28.64, 28.74 and 27.21 % for ADL, 53.82, 54.08 and 48.55 % for selluloze and 52.52, 52.05 and 48.60 % for hemisellusose in K, P and T groups, respectively ( P<0.05).

The average ammonia values of ruminal fluid in K, P and T groups were found as 21.38, 20.0 and 18.04 mg/100 ml, respectively ( P<0.05). The rates of asetic acid in the total volatile fatty acid were 75.07, 75.71 and 77.40 %, propionic acid 16.74, 16.31 and 15.03 % and butyric acid 8.19 , 7.98 and 7.57 % in K, P and T groups, respectively (P<0.05).

At the end of the research, average of daily dry matter intake, daily weight gain and feed efficiency of the lambs in K, P and T groups were 706.43, 693.11 and 544.89 gr,147.92, 139.87 and 98.21 gr and 5.58, 5.73 and 5.93, respectively ( P<0.05).