The effect of the quality of dietary lignocellulose on digestion, zootechnical performance and health of the growing rabbit

The aim of this study was to evaluate the performance and digestive respons e of the growing rabbit according to a change in the nature of the lignocel lulose (ADF), without a change in the ADF level. Three diets with a linearl y decreasing lignin/cellulose ratio (ADL/cellulose = 0.8; 0.4; 0.2; respect ively LC8, LC4, LC2) were given to a total of 162 rabbits per diet, from we aning till slaughter weight. A reduction of the ADL/cellulose ratio led to a lower food intake (LC8 v. LC2: -11%), associated with a lower daily weigh t gain (-6% for LC2). Mortality and morbidity rate was significantly greate r (+50%) for LC2 and LC4 diets compared with the LC8. Thus, the health risk index (morbidity + mortality) increased by 20 units for LC4 and LC2 compar ed with LC8 diet. In parallel, rate of passage was slower (mean retention t ime 4.5 h greater, P = 0.045) with LC4 and LC2 diets. Dry-matter digestibil ity was slightly affected, whereas protein digestion was favoured with low ADL/cellulose ratio. It is recommended that a minimum lignin supply (about 6 g/day) is adopted as well as a minimum dietary lignocellulose to ensure g rowth performance and health of the growing rabbit.