title: Intestinal villus recovery in chickens refed semi-purified protein-, fat-, or fibre-free pellet diets.
abstract: 1. To determine which macronutrient, protein, fat, or fibre is most effective at inducing structural recovery of intestinal villi after feed withdrawal, male layer chickens were allotted to the following groups: intact control (IC), 3-d feed withdrawal (F), ad libitum refeeding of a formula mash diet (AFM), or force-feeding of a formula (FFP) or semi-purified well-balanced (FSP), protein-free (FSPP), fat-free (FSPF), or fibre-free (FSPFi) pellet diets for one day after 3-d feed withdrawal. 2. After refeeding, the formula diet groups increased in villus height and apparent area. However, not all of the semi-purified groups recovered to the levels of the formula diet groups in all light microscopic variables, except in terms of a further decrease in cell mitosis in the FSPP group compared to the F group. Of the semi-purified groups, the FSPFi group tended to be the highest for all variables. This result suggests that the semi-purified diets did not induce villus recovery faster than the formula diet, especially in the case of the protein-free pellet diet. 3. After refeeding, a smooth surface of villus tip in the F group changed to a rough surface, with cell protuberances in the AFM group. This morphological recovery was clearer in the FFP group. Compared with the FFP group, the semi-purified groups had cell protuberances which extended further into the intestinal lumen, and more cell clusters. Among the semi-purified groups, epithelial cells were smaller in the FSPP and larger in the FSPFi than in the other groups. This result suggests that the semi-purified diet can induce a quicker cell recovery than the formula diet but that the protein-free diet is the slowest. 4. The present study demonstrates that protein is the most important nutrient for the recovery of intestinal villi after feed withdrawal.
authors.affiliation: Laboratory of Animal Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa-ken, Japan.
authors.forename: B
authors.initials: B
authors.lastname: Maneewan
authors.forename: K
authors.initials: K
authors.lastname: Yamauchi
mesh_terms: D000821:Animal Feed; D000818:Animals; D001835:Body Weight; D002645:Chickens; D004032:Diet; D004044:Dietary Proteins / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000502:physiology*; D008297:Male; D008855:Microscopy, Electron, Scanning; D008871:Microvilli / Q000502:physiology* / Q000648:ultrastructure; D008892:Milk
chemical_list: D004044:Dietary Proteins