Эффективность введения кормовой добавки из левзеи сафлоровидной в рацион молодняка крупного рогатого скота

The article presents the results of experiments on feeding 1-4 month old calves with immunostimulating feed additive of leuzea safflower as a part of mixed fodder. The plantation of leuzea safflower, established in 2010 at the experimental field of Perm Research Institute of Agricultural Sciences, PFRC UB of the RAS, is used up to the present time. A fodder phytosupplementwas prepared from the green mass of safflower and then used as part of an experiment on young cattle. The supplement was included in the ration of two experimental groups of calves in the amount of 3.00 and 6.00% of the dry matter of the concentrate part of the ration. The duration of feeding was 92 days (from 32 to 123 days of rearing). In the sample of the experimental phytosupplement from Leuzea safflower concentration of 20-hydroxyecdysone was 0.394 % in the active substance at the recommended content of 20-hydroxyecdysone (20E) from 0.25 to 0.45 %. The tested feed phytosupplement increases biological adequacy of calf ration. This favours better digestion of feed nutrients by animals of experimental groups. Dry matterdigestibility coefficients in calves of I and II experimental groups were higher by 0,49 and 2,88%, organic matter by 2,33 and 3,12%, crude protein by 1,57 and 2,14%, crude fat by 1,26 and 1,77%, crude fibre by 8,58 and 10,92%, in comparison with the control group. Calves of I and II experimental groups utilised more calcium and phosphorus from the actual diet by 2.31 - 2.63% and 1.85 - 2.47%, respectively, compared to the control group. When feeding the additive in the amount of 6.00% of thedry matter weight of mixed fodder, the coefficients of digestibility of nutrients of diets, the use of nitrogen and minerals were higher, so this dose is recommended to be included in the ration of calves of 1 - 4 months of age.