Effect of diets NDF levels on growth performance and intestinal mucosa morphology of weaned rex rabbit | 日粮NDF水平对断奶獭兔生长性能和肠道形态的影响

Chinese. 研究日粮中性洗涤纤维(NDF)水平对断奶獭兔生产性能、肠道形态、盲肠pH值、腹泻率、死亡率和血液碱性磷酸酶(AKP)活性的影响。将56只体质量相近((432.11±11.17) g)的35 d断奶獭兔，随机分为4组，分别饲喂含质量分数29%，33%，37%和41%NDF的日粮，进行28 d的饲喂试验，于14和28 d测定各组采食量和体质量，计算各组生产性能。饲喂结束后，屠宰并及时采集血液和肠道样品，测定肠道绒毛高度和隐窝深度及血液AKP活性、盲肠pH值、腹泻率、死亡率。各NDF处理组间的生产性能差异显著(P＜0.05)，其中33% NDF组的平均日增质量显著高于37% NDF组和41% NDF组(P＜0.05)，料质量比显著低于29% NDF组和41% NDF组(P＜0.05)。日粮NDF水平对十二指肠肠绒毛高度和隐窝深度、空肠肠绒毛高度的影响均不显著(P＞0.05)；日粮NDF水平对空肠隐窝深度有显著影响 (P＜0.05)，表现为低水平NDF使空肠隐窝加深；日粮NDF水平对回肠肠绒毛高度、隐窝深度和肠绒毛高度/隐窝深度都有显著影响(P＜0.05)，表现为41% NDF组的肠绒毛高度和隐窝深度均较其他组高，而肠绒毛高度/隐窝深度值显著低于29% NDF组(P＜0.05)。腹泻率和死亡率随着日粮NDF水平的升高呈降低趋势，AKP活性在各组间无显著差异，盲肠pH值随日粮NDF水平的提高而总体升高，且37% NDF组和41% NDF组盲肠pH显著高于29% NDF组和33% NDF组(P＜0.05)。高NDF水平日粮可降低断奶獭兔腹泻率，影响其肠道形态，当日粮NDF质量分数为33%时1～2月龄獭兔生产性能最好。

English. An experiment was conducted to determine the effects of different levels of diets NDF on growth performance, intestinal mucosa morphology and cecal pH, diarrhea percentage and plasma AKP of rabbit. Fifty-six 35-d old healthy weaned rex rabbits were randomly divided into 4 groups, and fed the diets with NDF level of 29%, 33%, 37% and 41% respectively for 28 days. Feed intake and body weight were determined on day 14 and 28, respectively. After sampling blood in heart, the rabbit were blunt to death, and the intestinal samples were collected immediately to determine intestinal villous height and crypt depth. Results showed that the growth performance of 4 groups was different (P0.05). The average gain (AG) of NDF 33% group was higher than 37% group and 41% group (P0.05), and the feed conversion rate was lower than 29% and 41% NDF groups (P0.05). There was no effects of diets NDF levels on villous height, crypt depth of duodenum and villous height of jejunum (P0.05); the crypt depth of jejunum 29% group and 33% group were higher than group 37% (P0.01), and low NDF level increased the crypt depth. With 41% NDF in diet, jejunum villous height and crypt depth were higher than the other groups. The ratio of villous height to crypt depth was lower than 29% NDF group (P0.05). Diarrhea percentage and mortality were decreased with increasing diet NDF level. AKP activity were similar between the treatments (P0.05). Cecal pH was increased with increasing diet NDF level, and diet with 37% and 41% NDF group were higher than group with 29% and 33% diet NDF. In conclusion lower NDF diets can raise the growth performance, while higher NDF diets can raise the villous height and effects intestinal morphology. The group of NDF 33% rabbits’ growth performance is the best.