The experiment was conducted using 360 turkey-hens of heavy type Big-6 divided into 4 groups (each with three replicates of 30 birds). All birds were fed with identical standard fulldose mixtures in a 5-stage system. An addition of tested supplements Echinovit C, garlic, and 1,2,4-triasole derivative was given with drinking water. The birds in group I (control) did not receive additives. The turkey-hens of group II received natural poultry immune stimulant Echinovit C, at the daily dose of 0.25 ml/dm3 of water. The birds in group III were given fresh and ground garlic at the daily dose 0.25 g/dm3 of water. The turkey-hens of group IV daily were given 1,2,4-triasole derivative in the amount of 25 μg/dm3 of water. All supplements were given from the first day of life during the entire period of rearing period twice in week. At the end of the experiment after 16 weeks, the birds in group III (receiving garlic) were significantly, 600 g, i.e. 6.5%, heavier than in the control group. The addition of garlic favorably affected the feed conversion ratio. The turkey-hens of this group used on average 4.8% less feed per kilogram gain than the birds in the control group.