Abstract. In order to study the effect of fresh blue algae Spirulina platensis biomass on pigs fattening rate and meat
quality an experiment was carried out with 85-days-old crossbreds of Landrass and Yorkshire. Two groups - control
and experimental - were formed, each containing 16 pigs. Both groups ofthe pigs were fed standard concentrate forage.
1 kg of forage dry matter contained 13.4 MJ AE and 16 % of crude protein. The pigs ofthe experimental group were
given daily and individually 2 g of 75 % humidity fresh blue algae Spirulina platensis biomass with forage. The pigs
were weighed at the beginning and the end of the experiment. Confrol fattening was considered to be finished when pig
weight reached 95 kg. At the end of the experiment, control slaughtering was performed. It was determined that the
average daily weight gain ofthe pigs given 2 g of 75 % humidity fresh biomass of blue algae Spirulina platensis was by
9.26 % higher, 100 kg of weight was reached by 7.37 days faster, and the amount of AE consumed for 1 kg of weight
gain was by 1.28 MJ AE lower than in the confrol group. Carcass output ofthe experimental pigs was by 2.02 % higher
and the amount of intramuscular fat- by 0.33 % lower than in the control group of pigs.