Impact of caecotrophy on rate of passage, intake and faecal excretion pattern in the growing rabbit

Abstract

[EN] Rate of passage was measured on 12 rabbits, either allowed to practice caecotrophy (Control period, from 56 to 60 days of age) or prevented from consuming soft faeces by wearing a plastic collar (without soft faeces intake = WSF periods, 63-66 d old and 70-73 d old). Measurements of digestive transit of the solid phase of the digesta were carried out by analysing the kinetics of faecal excretion of a fibre particles labelled with 141Ce. The excretion pattern of hard and soft faeces, hourly quantified during three complete 24-h cycle during WSF periods, showed that hard faeces excretion averaged 35.3 ± 3.2 g/day DM, while caecotrophes excretion was meanly 10.7 ± 2.6 g DM/d for a mean feed intake of 113.7 g DM/d. During the control period, daily hard faeces excretion was not significantly different (36.4 ± 3.0 g DM/d, for a feed intake of 110.8 g DM/d). The DM digestibility did not differ during control and WSF periods (67.2 and 67.8%). If caecotrophe production is included in the DM digestibility calculation, coefficient fell by 10.5 units (mean = 57.3%). When soft faeces intake was prevented (period WSF), the mean retention time in the whole tract evolved from 23 h (Control) to 15 h (-34%) and the minimal transit time was 50% shorter. The caecal mean retention time passed from 17 h in Control to 10 h (-40%) in WSF period. Caecal retention of large particles seemed less affected (CRlp:- 23%) than fine (CRfp:-48%).