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111.
112.
The effect of a novel lairage environment on the ability of sheep to recover from 16 h of transport was investigated. Sheep were transported from grass paddocks to either novel outside paddocks or inside pens, and housed groups were transported to either familiar or novel inside pens. During transport, sheep from outside paddocks lay down less than those from inside pens. In sheep transported to inside pens, those from outside paddocks spent more time lying and spent less time eating; hay and water intakes during the first 12 h post-transport were lower than those previously kept inside. There was no obvious effect of a novel environment post-transport on blood biochemistry, suggesting that the lower post-transport feed and water intakes in a novel environment did not have a significant effect on the ability of the sheep to recover from the feed and water deprivation associated with transport.  相似文献   
113.
雷琼牛肌肉生长抑制素基因序列研究   总被引:1,自引:0,他引:1  
通过PCR方法对18头雷琼牛的MSTN基因进行扩增、测序.编码区序列分析结果表明:雷琼牛MSTN基因比外域瘤牛存在较丰富的多态性,共发现4个突变位点(2个转换,2个颠换),定义了6种单倍型,群体单倍型多样性较高(0.810±0.057);分析结果表明:MSTN基因的相关突变的发生可能早于Bos属瘤牛、普通牛、牦牛的分化;在瘤牛种内,我国南方的瘤牛可能是更原始的种群.  相似文献   
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116.
Detection of Actinobacillus pleuropneumoniae Infection in Pigs   总被引:8,自引:1,他引:8  
It is difficult to control the spread of porcine haemophilus pleuropneumonia caused by Actinobacillus pleuropneumoniae because there is no sensitive and specific way to accurately determine whether or not a pig herd is infected. This paper reports bacteriological and serological techniques used to detect A. pleuropneumoniae infection in pigs from a herd with endemic disease.

The bacteria were isolated from the anterior nasal mucosa of grower pigs, but not from younger or older pigs. Bacteriological culture of several tissues from the respiratory tract showed that nine of ten young finishing pigs were infected, but culture of lung tissue from slaughtered hogs detected infection in only 39 of 288 (13.5%). Both cooler storage temperature and use of selective medium prolonged the time that lung tissue could be stored and the organism still recovered. An enzyme-linked immunosorbent assay detected serotype-specific antibodies in serum of infected pigs.

  相似文献   
117.
Abstract

Extract

Sheep ova are normally obtained from the reproductive tract using the flushing techniques described by Hunter et al. (1955) Cumming, I. A. and McDonald, M. F. 1967. The production of ova by New Zealand Romney ewes following hormonal stimulation. N.Z. Jl agric. Res., 10: 226236. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar]. Oviduct flushes, in the writers' experience, give a higher recovery of ova than uterine flushes, but they result in more adhesions of the tract, which can cause infertility. Consequently, the development of satisfactory uterine flushing techniques appears necessary before ova can be recovered repeatedly from superior ewes. This paper describes such a technique.  相似文献   
118.
Carbon kinetics of milk formation in Holstein cows in late lactation   总被引:3,自引:0,他引:3  
Carbon transfer to milk in Holstein cows in late lactation was measured by introducing changes in the natural stable carbon isotope composition of the feed. Six Holstein cows in mid-lactation were placed on a diet naturally low in 13C (-25.0% vs Pee Dee belemnite [PDB] an international carbon isotope standard), based on alfalfa-barley, and six others were placed on a diet naturally enriched in 13C (-11.5% vs PDB), based on corn. After a 7-wk equilibration period on these diets, three cows were switched from alfalfa-barley to corn, and three were switched from corn to alfalfa-barley. The three other cows in each group served as controls. 13C/12C ratios were measured in daily morning milk samples during the week before and for 6 wk after the changes in diet. After the diets had been switched, milk isotope ratios rapidly approached the isotopic composition of the new diet, indicating rapid transfer of dietary carbon into milk. The data were consistent with a model whereby milk was synthesized from a single precursor pool that responded rapidly to dietary perturbation. The milk precursor pool had a half-life of approximately .9 d and had a mass of approximately 7 kg of carbon, which was renewed daily by the entry of 5 kg of digestible dietary carbon.  相似文献   
119.
Coffee wilt disease (CWD) caused by Fusarium xylarioides, considered to be a soil-inhabiting fungus, is endemic in several African countries, affecting commercially important coffee species and causing serious economic losses. Coffee wilt disease development in naturally infected Coffea canephora fields at the Coffee Research Institute in Uganda was assessed from April 2001 to March 2006 to generate information about temporal and spatial spread of the disease. Maps of diseased trees were also generated from the data. Semi-variance analysis was performed on the data to show the spatio-temporal structure of disease. Host influence on the spatio-temporal structure was deduced from the distribution pattern of diseased and healthy trees and analysis of variance. Results show that the temporal disease epidemic progress was slow. The disease was found to spread from initial infections to healthy neighbouring trees, resulting in an aggregated pattern. An infected tree could infect up to three healthy trees away, in any direction. Disease foci formed and expanded with time, coalescing but punctuated in spots planted with resistant hosts. There were varying levels of susceptibility among host genotypes, affecting the rates and levels of epidemic development. The implications of the findings to the control of CWD are discussed.  相似文献   
120.
马关县草果种植地的施肥效果试验   总被引:1,自引:0,他引:1  
在马关县仁和镇的4年生草果种植地开展了施用不同量的农家肥、钾肥、普钙和复合肥促进草果植株开花结实效果的试验。结果表明:对该地的草果种植地进行合理的施肥能有效促进草果植株叶芽、花芽的分化,提高其结实率及结实量。各施肥处理的草果植株在叶芽数量、花芽数量、结实率及结实量等4个指标上均优于不施肥的对照,分别比对照提高了24.4%~204.9%、22%~97.6%、5.4%~36.9%和72.4%~442.3%。各施肥处理的草果植株在叶芽数量及结实量2个指标上存在极显著的差异,而在花芽数量及结实率2个指标上无显著差异。综合各施肥处理的草果植株结实量及结实率,在马关县及其土壤状况相似的草果种植地较佳的施肥肥种为钾肥或复合肥,其施肥量为钾肥200 g/株(丛)或复合肥400 g/株(丛),前者草果植株单株(丛)的结实量达8.46 kg,比不施肥的对照高442.3%,后者草果植株单株(丛)结实量达7.82 kg,比不施肥对照高401.3%。  相似文献   
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