Effect of Feeding Insoluble Fiber on the Microbiota and Metabolites of the Caecum and Feces of Rabbits Recovering from Epizootic Rabbit Enteropathy Relative to Non-Infected Rabbits

This study aimed to investigate the effect of feeding insoluble fiber on the microbiota and metabolites of the caecum and feces of rabbits recovering from epizootic rabbit enteropathy relative to non-infected rabbits. Rabbits that had either recovered from epizootic rabbit enteropathy or ones that had never had epizootic rabbit enteropathy were fed on a diet of 32% or 36% neutral detergent fiber until they were 70 days of age. At this point, the short-chain fatty acid and ammonia levels were measured in caecotroph and fecal samples and compared using 2 × 2 ANOVA. The microbial composition of the samples was also analyzed using next-generation sequencing and compared by PERMANOVA. Caecotrophic samples from previously affected rabbits on lower fiber diets had higher short-chain fatty acid contents and higher species diversity index values for some indices (p < 0.05), although the fecal samples showed lower species diversity levels (p < 0.05). In addition, the PERMANOVA analyses demonstrated that differences were detected in the microbial composition of both fecal and caecotrophic samples, depending on the disease status at the outset of the experiment (p < 0.05). The results of this work show that, although there is some potential in the use of high-fiber diets for the treatment of rabbits that have had epizootic rabbit enteropathy, they are not able to produce the same digestive tract properties as those seen in rabbits that have never had the condition. This is true even after the rabbits have recovered from epizootic rabbit enteropathy.

The Health and Welfare of Rabbits as Indicated by Post-Mortem Findings at the Slaughterhouse

Simple Summary

Veterinary inspection at the slaughterhouse plays an important role in the surveillance system for animal health and welfare. The study focused on the quantification and identification of pathological findings in rabbits slaughtered at the slaughterhouses in the Czech Republic in the period from 2010 to 2019. The ratio of the number of pathological findings to the total number of rabbits slaughtered was 0.0214, i.e., for every hundred rabbits, 2.14 findings were made documenting the impairment of health and/or welfare to an extent leading to pathological changes detected during the post-mortem inspection of the rabbits at the slaughterhouse. The pathological findings that occurred most often were those on the limbs (0.84%), trunk (0.71%), kidneys (0.17%), and liver (0.05%), along with generalized changes (0.37%). The results show that findings on the limbs and trunk were dominated by findings of traumatic origin. Findings in the kidneys and liver were most often of a chronic nature. Findings of abscesses were most frequent among generalized findings.

Abstract

The aim of the study was to assess post-mortem findings according to their localization and the nature of damage and to assess the standard of health and welfare of farmed rabbits on the basis of these findings. A total of 40,206 pathological findings were recorded in 1,876,929 rabbits slaughtered at slaughterhouses in the Czech Republic in the period from 2010 to 2019. Pathological findings on the limbs (0.84%), the trunk (0.71%), the kidneys (0.17%), and the liver (0.05%), along with generalized changes (0.37%), occurred most frequently. Findings of traumatic origin dominated among findings on the limbs and trunk, which indicates the inappropriate housing and handling rabbits on farms and during transport. Findings in the kidneys and liver were most often of a chronic nature having an evident correlation with the diet of intensively fed rabbits, with shortcomings in the diet having an impact on the parenchyma with chronic manifestations in the liver and kidneys. Among the generalized findings, multiple abscesses, which were probably associated with the infection of injuries occurring during fattening, and emaciation resulting from current husbandry practices, leading to insufficient feed intake or the development of disease in some individuals, predominated.

Dietary supplementation of chestnut and quebracho tannins mix: Effect on caecal microbial communities and live performance of growing rabbits

The interest in antimicrobial compounds as feed additives is currently increasing. Among different options, tannins seem to have several beneficial effects when employed in animals diet. The present study aimed at investigating the influence on caecal microbial communities of the supplementation of a chestnut and quebracho tannins mix in meat rabbit's diet, also considering animals live performances. Four groups of rabbits were fed with a different diet: a control diet (C); a control diet with coccidiostat (CC), and two experimental diets with 0.3% (T0.3) and 0.6% (T0.6) chestnut and quebracho tannins mix. For microbial analysis, culture-dependent and culture-independent methods were employed. Live performances were not significantly affected by tannins mix supplementations, as well as culturable microbial loads of E. coli, Enterobacteriaceae, Bacteroides spp. and Bifidobacterium spp. C. perfringens was always under the detection limit. A consistent result was obtained by qPCR. As for PCR-DGGE analysis, the Richness and evenness (Shannon-Weiner index) of bacterial communities in caecum resulted significantly higher in control samples (C and CC) than in those from rabbit fed with tannin-containing diets. Sequencing analysis revealed that the phylum Firmicutes was less represented in samples from control groups. As for the methanogen archaeal DGGE, no significant differences were found in richness and diversity among different groups, all dominated by Methanobrevibacter spp.. This work highlights the potential antimicrobial effect of chestnut and quebracho tannins mix in an in vivo system revealed by molecular analysis.