Digestive capacity of the rabbit during the post-weaning period, according to the milk/solid feed intake pattern before weaning

Abstract

-The milk/solid feed intake pattern and digestive capacity were compared in two groups of young rabbits reared between 16 and 32 days in litters of four (L4 group, n = 18 litters) or ten pups (L10, n = 20) in order to modulate milk availability. Compared to the L4 group, rabbits in the LIO group presented a lower milk intake (22.3 versus 28.8 g-day-1 ) and a higher solid feed intake (12.9 versus 8.0 g-day-1 ) between 16 and 32 days of age. Live weight and weight gain were significantly lower in the L10 (-15 %) than in the L4 group from 22 until 42 days. No significant difference was observed among the two groups for post-weaning digestibility and for the intraluminal specific or total activities of amylase and maltase. The total intraluminal activity (pool of enzyme) of amylase and maltase doubled between weaning (32 days) and 42 days. At weaning, the specific activity of amylase was similar in the jejunal and ileal segments (8.5 AU-g-1 ). From 32 to 42 days, the specific amylase activity doubled in the jejunum, while it remained steady in the ileum. The intraluminal specific maltase activity did not significantly change between 32 and 42 days, while it was twice as high in the jejunum compared to the ileum (3.5 versus 1.8 pmoles hydrolysed maltosei-g-1 , respectively

Adaptability of the digestive function according to age at weaning in the rabbit: I. Effect on feed intake and digestive functionality

“…Our results showed that availability of pancreatic amylase and lipase for substrates in the small intestine increased with age, which is in agreement with the age increase of their activities previously described in the pancreas Dojanȃ et al, 1998;Debray et al, 2003). The increase in amylase activity probably results from the higher starch intake with age (Marounek et al, 1995;Scapinello et al, 1999), and should correspond to an increasing capability of rabbits to digest starch. Conversely, in our study, the increasing lipase activity with age was not parallel to crude fat intake, which sharply decreased at weaning (from milk having 9% to 16% lipids to solid vegetal feed with 3% to 5% lipids).…”

“…Other authors showed, however, that an increased starch or lipid intake did not influence amylolytic and/or lipase activities around the weaning age (Scapinello et al, 1999;Debray et al, 2003). These discrepancies may be due to differences in methods, time of sampling or target tissue for assays.…”

Effect of cereal sources and processing in diets for the growing rabbit. II. Effects on performances and mortality by enteropathy

“…Sanitary risk would be higher, for the young rabbit (period post-weaning) since the data of digestive physiology indicate that the secretion of amylolytic enzymes still develops until 42 d of age [5,15]. Thus, an excessive starch flow entering the caecum could be unfavourable to the fibrolytic flora, itself in a phase of development [1,6].…”

Effect of cereal sources and processing in diets for the growing rabbit. I. Effects on digestion and fermentative activity in the caecum

“…It was supposed that high starch incorporation in rabbit feeds, or starch of low digestibility, leads to digestive disturbances, because an intestinal starch overload could result in a high starch flow in the ileum and to a caecal ecosystem unbalance [6,18] and changes in caecal fermentative activity [13]. This problem would be particularly critical in the young rabbit having an incomplete maturation of starch digestive capacity [9,19,28] and a recent study addressed the problem of the starch quality in feeds for early weaned rabbits [17]. Moreover, very few works have only studied the effect of the starch nature, without variations in starch/fibre levels or in other nutrients.…”