The efficiency of probiotics in the diets for growing and productive broiler parental flock
The efficiency of periodic supplementation of diets for broiler parental flock (cross ISA Hubbard F-15, 100 birds per treatment, from 3 to 371 days of age) with two different probiotics (Levucell SB Plus and Cellobacterin-T) was studied. The probiotics were given to growing pullets (3-45 days of age), at the transition of grown pullets to parental flock and at the intensity of lay 5% (142-187 days), at the peak of egg production (241-270 days), and at the decline of egg production (316-337 days of age). It was found that probiotics significantly increased daily weight gains in compare to unsupplemented control, and improved mortality level and flock uniformity. Egg production in grown pullets fed probiotics was significantly higher (P≤0.001) since 204 days of age to the end of the trial; egg weight at all ages was not affected. Hatchability of eggs in experimental treatments at the peak of egg production was higher by 1.0-1.4% in compare to control, hatch of chicks was significantly higher by 2.7-4.2% (P≤0.05). The probiotics studied also improved mortality throughout the productive period, and decreased feed expenses.