Apports de cellulose dans l'alimentation du lapin en croissance. II. Conséquences sur les performances et la mortalité

Abstract

The effects of the level and botanical origin of dietary cellulose (Cell = ADF-ADL) on growth performance and mortality were studied in six experimental sites on 2 315 growing rabbits. Five diets were compared: a control diet (RO) with a low cellulose content (9.3%) and four diets with increasing cellulose content (12.4% and 15.9%) provided by wheat straw and alfalfa (diets P1 and P2) or by soyabean hulls and alfalfa (diets CS1 and CS2). Cellulose was replaced mainly by starch without change in dietary lignin and hemicellulose levels. Diets were given ad libitum from weaning (28 and 32 days old, depending on the site) to slaughter (between 68 and 73 days old). The reduction of cellulose level led to a linear increase of mortality rate (Tm) by digestive disturbances according to the relation: Tm(%) = 21.2- 1.07 Cell(%) (r2 = 0.92, ETR = 1.06), without the influence of the origin of dietary cellulose. Growth performance was affected by both the level and origin of cellulose. Feed conversion ratio increased by about 0.1 point per additional point of dietary cellulose.