Even Low Amounts of Amorphous Lignocellulose Affect Some Upper Gut Parameters, but They Do Not Modify Ileal Microbiota in Young Broiler Chickens

A feeding trial was carried out using 576 Ross 308 male chickens to test the effects of an amorphous lignocellulose (LC) product (Arbocel). Three dietary treatments (control, 0.5% LC (LC 0.5), and 0.8% LC (LC 0.8) were used, and the diets were fed in eight replicate pens of 24 chickens. The LC treatments did not modify the weight gain of the chickens, but they tended to decrease the feed intake and FCR in the grower phase. The high swelling characteristics of LC resulted in lower dry matter (DM) contents in the crop <i>(p</i> < 0.002) and gizzard (<i>p</i> < 0.047) on day 14 and day 24, respectively. The lower pH in the gizzard and duodenum of LC diets suggests longer retention time and more HCl secretion in the proventriculus and gizzard. Except for α-amylase on day 24, the treatments did not modify the digestive enzyme content of the jejunum. The microbiota diversity and microbiota composition of ileal contents were affected only by the age of birds. The results suggest that the LC product can exert its potential positive effects mainly in the upper part of the digestive tract due to its special physical characteristics. LC can slow down the passage rate in the gizzard and modify the digestion and the dynamics of water absorption from the jejunum and ileum.