Michaela Fels ^1* Livia Benato ² Alexandra Whittaker ³

• ¹ University of Veterinary Medicine Hannover, Hanover, Germany
• ² University of Bern, Bern, Bern, Switzerland
• ³ University of Adelaide, Adelaide, South Australia, Australia

presented in this Research Topic deals with digestive impairments in rabbits, the risk of antibiotic resistance, and group housing of breeding does. All of these topics also have relevance to the keeping of rabbits as pets as well as laboratory animals. Thus, the three papers add a valuable contribution to the current literature that can be used for all areas of rabbit housing.Digestive problems are very common in rabbits and often lead to high animal losses, especially in fattening rabbits (Solans et al., 2019). The article by van der Sluis, van Zeeland and de Greef highlights the possible causes of indigestion in rabbits and identifies two pathways: the "overload" pathway and the "chymus jam" pathway. The "overload" pathway is caused by an excess of easily fermentable substrates in the feed, which reach the cecum incompletely digested. Normally, proteins and starch are digested mainly in the small intestine. If starch and proteins increasingly enter the cecum, the digestive processes that take place there lead to a change in the cecum pH with a negative influence on the microorganisms located there. The other pathway ("chymus jam") is caused by a reduced motility of the hindgut resulting from stress or a too limited fiber supply. Ultimately, overfilling of the cecum and proximal colon occurs, thus resulting in a "chymus jam" and increased cecal retention times. This in turn leads to a negative influence on the microbial flora of the cecum. The authors explain that they wanted to shed light on non-specific digestive disorders in rabbits. This primarily, but not 36 exclusively, relates to rabbits raised meat production. Rabbit digestive tract mechanisms are 37 whether animals are reared for meat production, in labs or kept as pets and thus learnings from this 38 paper apply to all. According to the authors, their findings could be a starting point for further research 39 into feeding-related impairments of digestion in rabbits with the aim of improving the health and well-40 being of rabbits in the long term. 41Another important issue, which is highly relevant in the keeping of rabbits for meat production, is the 42 growing concern of antibiotic resistance to various bacterial pathogens. In a study by Sun et al., the 43 antibiotic resistance spectrums of Escherichia coli (E. coli) and Enterococcus spp. strains against 44 commonly used antimicrobials from commercial meat-rabbit farms in Chengdu City, Southwest China alfalfa and wooden panels and no enrichment (control). In this study, does were housed in groups 72 of four animals together with their litters from day 22 until day 32 post partum. On all observation 73 days, the number of injured does was higher in the control group than in the groups with alfalfa blocks 74 and in the groups where both materials (alfalfa and wooden blocks) were provided. However, severe 75 injuries still occurred in all groups. The authors conclude that the high prevalence of injured animals, 76 even in the enriched multi-litter cages, indicates that more effective or additional strategies are 77 needed to reduce the welfare problems in group housing systems for does. Much work still needs to 78 be done in this field of research to find systems and strategies that would enable breeding females to 79 kept in groups and thus allow them to express their natural social behaviour. 80In summary, the studies published in this Research Topic have provided new insights into important 81 issues related to rabbit husbandry. At the same time, the need for further research has been 82 highlighted, as the topics relating to the well-being and health of rabbits are very complex and many 83 things have not yet been scientifically clarified. Whether it is the intestinal health, the controlled use 84 of antibiotics or social behaviour in group housing -there is a need for further research everywhere. 85 This Research Topic is therefore intended to encourage continued intensive work on issues relating to 86 the welfare of rabbits so that new ways can be found to improve the rabbits' life. 87