摘要
通过阉牛咀嚼试验(试验1)、瘤胃和全消化道消化试验(试验2)和饲养试验(试验3)评价玉米和小麦谷实整粒或粉碎饲喂对于阉牛的饲喂价值。试验1采用4头装有永久性瘤胃瘘管的荷斯坦阉公牛(平均体重310kg)按4×4拉丁方试验设计,研究饲粮中玉米和小麦谷实整粒或粉碎饲喂对采食、反刍和咀嚼时间的影响。4种饲粮处理分别为粉碎玉米饲粮(GRC)、整粒玉米饲粮(WHC)、粉碎小麦饲粮(GRW)和整粒小麦饲粮(WHW)。结果表明,饲粮中玉米或小麦的粒度显著影响动物24h期间的咀嚼时间(P<0.02),但咀嚼时间的反应模式随谷物种类的不同而异,其中与饲喂粉碎谷物相比,饲喂整粒玉米延长咀嚼时间76.2min(P=0.065),而饲喂整粒小麦则缩短咀嚼时间126.8min(P=0.009)。试验2是在试验1的基础上,采用与之完全相同的试验动物、饲粮处理和试验设计,研究玉米和小麦谷实整粒或粉碎饲喂阉牛的瘤胃和全消化道营养物质消化率。与饲喂粉碎谷物饲粮相比,饲喂整粒谷物饲粮时瘤胃pH和粪便pH趋于同步提高(P<0.03),但瘤胃发酵产生的总挥发酸浓度降低(P<0.02)。饲喂整粒谷物饲粮较粉碎谷物饲粮提高了尼龙袋小麦秸纤维组分的消化率(P<0.09),但不影响尼龙袋玉米干物质和淀粉的消化率(P>0.3)。饲喂整粒谷物饲粮全消化道DM。
Three experiments (Expt. 1, 2 and 3) were conducted to evaluate the effect of particle size and source of cereal grains included in the total mixed rations of growing beef cattle on the chewing activity, rumen and whole gastrointestinal tract digestibility and growing performance. In Expt. 1, four ruminally cannulated Holstein steers (310 kg of average body weight) were used in a 4×4 Latin Square design to determine the effect of grain particle size (coarsely ground or whole grain) and grain source (shelled dry corn and wheat grain) on the chewing activity of growing beef cattle. The result showed that the steer fed the whole grain diet spent more time on eating, ruminating and chewing than the animals fed the ground grain diet. The chewing activities followed different pattern between the source of cereal grains: longer time for feeding whole shelled corn diets, but shorter time for feeding the whole wheat grain diet. In Expt. 2, dietary treatments, animals and 4×4 Latin Square design similar to Expt. 1 were used to determine to the effect of grain particle size and source on rumen and whole digestive tract digestibility of growing beef cattle. Feeding the grain diets with different particle size resulted in an increase in rumen pH and fecal pH values (P<0.03) and a decrease in total VFA concentration (P<0.02), compared with feeding the ground grain diets. As whole grain diets were fed, there was an increased in situ disappearance (P<0.09) of wheat straw NDF and ADF, whereas there was an unchanged disappearance of corn DM and starch (P>0.3). In comparison with feeding the ground diet, feeding the whole grain diet led to depressed whole tract digestibility of DM, OM and starch (P<0.001), but had no influence on the digestibility of dietary NDF and ADF (P>0.3) with no change in blood urea and glucose concentrations (P>0.18). Expt. 3 was conducted using 62 Qinchuan steers in a randomly factorial design to investigate the effect of grain particle size and grain source on growing performance. The daily gain and feed conversion (F/G) were decreased by 11.8～13.6% (P=0.043～0.06) and 8.4～11.7% (P=0.035～0.137) with the whole grain diet, respectively, while dietary DM intake was unaffected (P>0.4) by the grain particle size. It was concluded that the comparative feeding value of whole cereal grains in the growing beef cattle diet is decreased, and appropriate processing including grinding prior to feeding is required.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2004年第6期626-632,共7页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家杰出青年基金(30125033)
关键词
饲喂
饲粮
玉米
小麦
阉牛
粉碎
消化率
咀嚼
消化道
影响
growing beef cattle
whole or ground grain
rumen fermentation
digestion
growing performance
