The mowing is the first technical operation performed in the scope of quality cattle food preparation technology. It needs to be done within optimal agro-tehnical time framework in order to decrease potential negative impacts of external factors. This  paper shows the losses created during alfalfa mowing process performed by oscillatory and rotary mower. The losses detected during research process have been divided into two groups: losses caused by increased incision height (over 6cm), and losses caused by crushing. The total losses made during mowing by the tested mower were calculated by  adding the incusion height losses and  crushing losses. The research  results of oscillatory mower indicate that the minimal losses caused by the incision height are 0.57% of yields, at the aggregrate mowing speed of 3.82 km/h. Aggregate mowing speed increase tend to  slightly increase the losses up to maximum values of 1.17% at the mowing speed of 8.17 km/h. The crunching losses ranged from minimal 0.31% at the maximum aggregate mowing speed, to maximum 0.43% at the minimal mowing speed. The average total losses of oscillatory mower were 1.18% of  yields, at  the  averagge aggregate mowing speed of  5.76 km/h. The research results of rotary mower indicate that the minimal losses caused by the incision height are  0.96% of  yields, at  the mowing speed of 8.32 km/h.Agreggate mowing speed increase tend to slightly increase the losses up to maximum values of 1.34% at the mowing speed of 10.34 km/h. The crunching losses ranged from minimal 1.61% at the maximum aggregate mowing speed, to maximum 2.18% at the minimal mowing speed. The average total losses of rotary mower were 2.99% of yields, at the average aggregate mowing speed of 9.39 km/h.Comparing research results, it is evident that the oscillatory mower has achieved significantly lower losses in comparison to the rotary mower. The average oscillatory mower losses were 1.18% of yield, whereas the rotary mower losses were slightly higher and were 2.99% of yields. Having in mind the obtained results for tractor oscillatory and rotary mowers used for alfalfa mowing, it may be concluded thet these results range within optimal values, that there are no significant differences and they are in conformity with resultes obtained by other authors.

:oscillatory mower, rotary mower, moving, losses, incision height

Presentation: oral