Abstract:To explore the effects of different levels of compound probiotics on the growth performance, intestinal morphology and intestinal microbial composition of white feather broilers under the condition of Clostridium perfringens infection. Three-day-old healthy white feather broilers which have been infected with Clostridium perfringens were fed a basal diet supplemented with high (500 mg/kg), medium (200 mg/kg) and low (50 mg/kg) doses of compound probiotics composed of Bacillus subtilis and Bacillus licheniformis and 50 Times new romang/g chlortetracycline for 21 days. The intestinal microbial composition in cecum of white feather broilers and its diversity and differences between groups were analyzed based on the second-generation high-throughput sequencing technology. The results showed that feeding high and medium doses of compound probiotics significantly decreased the feed to meat ratio and increased the villus height to crypt depth ratio of white feather broilers (P<0.05), similar to chlortetracyline preparation group. At the same time, the richness and diversity changed after feeding different doses of compound probiotics and chlortetracyline preparation, and the compound probiotics significantly improved the Simpson index (P<0.05). In addition, comparing the changes of dominant flora at phylum level between compound probiotics, chlortetracyline preparation and blank group, it was found that the relative abundance of Tenericutes decreased significantly (P<0.05). At the genus level, it was found that the relative abundance of Fournierella increased significantly. The relative abundance of Lachnospiraceae decreased significantly (P<0.05). The results reveal that compound probiotics can promote the growth performance and intestinal microflora structure of white feather broilers, providing an important theoretical basis for a more comprehensive understanding of the application of compound probiotics as a substitute for antibiotics in white feather broilers breeding.
