The novel probiotic preparation based on Lactobacillus spp. mixture on the intestinal bacterial community structure of Cherry Valley Duck

Abstract

Purpose The development and utilization of probiotics have many environmental benefits when they are used to replace antibiotics in animal production. In this study, intestinal lactic acid bacteria were isolated from the intestines of Cherry Valley ducks. Probiotic lactic acid bacterial strains were screened for antibacterial activity and tolerance to produce a Lactobacillus spp. mixture. The effects of the compound on the growth performance and intestinal flora of Cherry Valley ducks were studied. Method In this experiment, we isolated and screened lactic acid bacteria from healthy cherry intestine. The dominant lactic acid bacteria were screened by antibacterial test and tolerance test, and then the new probiotic preparation of lactic acid bacteria mixture was prepared by compound culture of lactic acid bacteria. One day old healthy Cherry Valley ducks were divided into two groups. One group was used as the experimental control, and the other group was used to evaluate the new probiotic preparation feeding group of lactic acid bacteria mixture. The 16S rDNA high-throughput sequencing technique was used to analyze the diversity of intestinal microorganisms in Cherry Valley ducks. Result Based on the results of the antibacterial activity and tolerance tests, the highly active strains Lactobacillus casei 1.2435, L. salivarius L621, and L. salivarius L4 from the intestines of Cherry Valley ducks were selected. The optimum ratio of L. casei 1.2435, L. salivarius L621, and L. salivarius L4 was 1:1:2, the amount of inoculum used was 1%, and the fermentation time was 14 h. In vivo experiments showed that compared with the control group, the relative abundances of intestinal Lactobacillus and Blautia were significantly increased in the experimental group fed the lactobacillus compound (P < 0.05); the relative abundances of Parabacteroides, [Ruminococcus]_torques_group, and Enterococcus were significantly reduced (P < 0.05), and the growth and development of the dominant intestinal flora were promoted in the Cherry Valley ducks. Conclusion The optimal proportion of the new probiotic preparation of lactic acid bacteria mixture is L. casei 1.2435, L. salivarius L621, and L. salivarius L4 was 1:1:2. It can promote the growth and development of the dominant intestinal flora of Cherry Valley ducks, and has made an important contribution to the healthy breeding of Cherry Valley ducks.