Effects of changes in frequency of reticular contractions on fluid and particulate passage rates in cattle.
Effects of changes in frequency of reticular contractions on fluid and particulate passage rates in cattle.
复制标题
网状收缩频率变化对牛体液和颗粒通过率的影响。
DOI：
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发表时间：
1989
影响因子：
3.3
通讯作者：
R. Hardin
中科院分区：
文献类型：
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作者：
E. Okine;G. Mathison;R. Hardin
采用4头瘤胃插管的赫里福德阉牛（531 +/- 32 kg，无体重（对照；C）或24 kg体重(W)）进行双交叉设计试验，以确定维持采食量网状收缩频率的变化对瘤胃颗粒物和液体通过率的影响。网状收缩持续时间、表观消化率、热和甲烷产量也被测定。饲喂前瘤胃重量对网状收缩频率无影响（P = 0.07）；然而，进食期间（P = .03）和进食后（P = .05）， C组网状收缩频率高于W组。瘤胃增重使采食前（P = 0.04）、采食中（P = 0.01）和采食后（P = 0.05）的平均收缩时间分别增加了12%、15%和15%。C组瘤胃颗粒流出率和全胃肠道颗粒流出率分别比W组低38%和49% （P = 0.001）。瘤胃重量使甲烷产量（升/天）降低29% （P = 0.001）。甲烷产量与瘤胃颗粒物流出率呈负相关（r = - 0.53; P = 0.034）。W型和C型的产热量分别为12.3和12.6 Mcal/d。瘤胃重量对表观消化率无影响。网状收缩的持续时间是影响瘤胃液和颗粒物质通过率的重要因素，而不是收缩的频率。随着传代速率的增加，甲烷产量降低。（摘要删节250字）
Four ruminally cannulated Hereford steers (531 +/- 32 kg) without weights (control; C) or with 24-kg weights (W) in the rumen were used in a double crossover design experiment to determine the effects of changes in frequency of reticular contractions at maintenance feed intakes on passage rates of particulate matter and fluid from the rumen. Duration of reticular contractions, apparent digestibilities and heat and methane productions were also determined. Weights in the rumen had no effect (P = .07) on frequency of reticular contractions before feeding; however, frequencies of reticular contractions were higher in C than in W steers during feeding (P = .03) and after feeding (P = .05). Weights in the rumen increased the average duration of contractions before feeding (P = .04), during feeding (P = .01) and after feeding (P = .05) by 12, 15 and 15%, respectively. Fractional outflow rates of ruminal and whole gastrointestinal particulate matter were 38% and 49% lower (P = .001) in C than in W steers, respectively. Weights in the rumen reduced (P = .001) methane production (liters/d) by 29%. Methane production was inversely correlated with fractional outflow rate for ruminal particulate matter (r = -.53; P = .034). Heat productions for W and C steers were 12.3 and 12.6 Mcal/d, respectively. Weights in the rumen had no effect on apparent digestibility. Duration of reticular contractions, in contrast to frequency of contractions, was the important factor influencing passage rates of both ruminal fluid and particulate matter. Methane production was decreased when passage rates were increased.(ABSTRACT TRUNCATED AT 250 WORDS)