Analysis of the relationship between caecal flora difference and production performance of two rabbit species by high-throughput sequencing

Abstract

The purpose of this experiment is to study the relationship between the difference in production performance between Sichuan White (SC) rabbits and New Zealand (NZL) rabbits and the diversity of caecal flora. Twelve pregnant SC rabbits and 12 NZL female rabbits were selected for this experiment. After delivery, the young rabbits were divided into two groups according to breeds, each group had 30 replicates, and each replicate had one rabbit. During the experiments, these rabbits were kept in the same room, and the temperature in the room was controlled at 12–25 °C, with a 16-hour light cycle every 24 hours. The nutritional composition of the feed and other environmental conditions were consistent. On the 59<sup>th</sup> day of the experiment, the caecum contents of the two groups of young rabbits were collected. The results showed that the survival rate of the SC rabbit group was higher than that of the NZL rabbit group, and the diarrhoea rate and average daily gain were lower than those of the NZL rabbit group (P < 0.05). The results of high-throughput sequencing of the 16S gene showed that compared with the NZL rabbit group, the relative abundance of Bacteroides increased, and the abundance of harmful flora Verrucomicrobia and Proteobacteria decreased (P < 0.05). Functional analysis of the microflora showed that the relative abundance of carbohydrate metabolism genes in the SC rabbit group was higher than in the NZL rabbit group. In conclusion, compared with the NZL rabbits, the SC rabbits have a more optimized intestinal flora structure and lower abundance of harmful bacteria. Moreover, the intestinal health level of SC rabbits is improved, and the tolerance to roughage of SC rabbits is increased.