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41.
SE RIDGE JT HARKIN† ‡ RT BADMAN† AM MELLOR§ JWA LARSEN¶ 《Australian veterinary journal》1995,72(4):150-153
SUMMARY: Johne's disease was diagnosed in 10 alpacas ( Lama pacos ) in Australia between February 1993 and May 1994. Eight of the animals were between 12 and 24 months of age, one was a 6-year-old female, and one was a 4-year-old male. Five, including the 6-year-old and the 4-year-old alpacas, showed weight loss and diarrhoea before death or slaughter. The other cases showed no clinical signs of Johne's disease but 4 gave a positive result on faecal culture and one gave a positive result on testing with the caprine ACID assay and had acid-fast organisms in its faeces. At necropsy, all cases had grossly enlarged mesenteric lymph nodes. Johne's disease was diagnosed after histological examination of the lymph nodes with conventional culture and polymerase chain reaction testing of tissue samples. This report outlines the clinical, epidemiological, and pathological findings in these cases. 相似文献
42.
C Kijora H Bergner J Bartelt K P G?tz J Szakacz A Sommer L Charastinova Z Ceresnakova 《Archives of Animal Nutrition》1992,42(3-4):287-300
Three heifers with live weights of 255, 261 and 300 kg were supplied with ileo-caecal re-entrant cannulas, jugular vena catheters and bladder catheters. The ration consisted of 4 kg maize silage and 4 kg wheat straw pellets. In a previous period 50% of the digesta flow was collected over 12 h/d on 5 consecutive days and stored in a deep-freeze. During the main period the re-entrant cannulas were disrupted and the flowing digesta was quantitatively collected. Precollected digesta and pectin were infused into the distal part of cannula hourly for about 30 hours. During the first 24 hours the digesta was also supplemented with 15N-labelled urea. The amount of pectin corresponded to about 10% of digesta dry mater. An analysis of urine, faeces, digesta and blood plasma were carried out. The application of pectin increased the 15N-incorporation in the bacterial protein of faeces from 4.7% (without supplementation in an earlier experiment) to 10.5% of the introduced 15N. The ammonia-fraction of faeces was markedly higher than the bacterial fraction. The 15N-utilization of urea by the microbes of large intestine was lower in the actual trial evident than with supplementation of starch in the anterior experiment. During the pectin administration the amount of urine increased in comparison with earlier experiments and according to the literature to about the 4.5 fold. The amount of passage of 15N at the ileum cannula (recycled 15N) was 3.8% of the 15N intake. It is the same amount as in experiments in which starch was applied. 相似文献
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Sven Gjedde Sommer Erik Steen Jensen Jan Kofoed Schj⊘rring 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):21-24
Abstract Absorption of volatilized ammonia after application of slurry onto the soil surface (sand) between rows of a wheat crop was studied in two experiments. The slurry was labelled with 15N-NH4. During seven days the accumulated gaseous N loss from the slurry varied from 6.9 to 11.1 g N m?2. In April ammonia losses from slurry applied beneath a 5 cm high wheat crop were equal to losses from slurry applied to a fallow, but 2.2% of the lost atmospheric ammonia was taken up by the leaves. In May ammonia loss from slurry applied between the rows of a 43 cm high crop was reduced by 6% compared to the loss from fallow, because of a reduced transfer of ammonia from the slurry to the air. Of the emitted ammonia 3.3% was absorbed by the canopy. 相似文献
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J R Smiley S E Sommer D J Jackwood 《Journal of veterinary diagnostic investigation》1999,11(6):497-504
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Chemical fertilizer use has contributed significantly to increased global food output in the past half century, especially in climatically favourable regions of the world. However, in drier agro‐ecological zones, such as in West Asia and North Africa (WANA) with a Mediterranean‐type climate, fertilizer use has been low but has increased rapidly in the past few decades. Chemical fertilizer use is now widely adopted in rainfed and irrigated agriculture. As elsewhere, fertilizer use is underpinned by concerns about biological and economic efficiency. Fertilizer use efficiency is central to the current concept of fertilizer best management practices (FBMP), which embraces right source, right place, right timing and right application method. In this brief review, we highlight such FBMP concepts as related to agriculture of the WANA region, with emphasis on the key nutrients for crop production. Rainfall has a dominant influence on dryland crop yields. Nitrogen (N) use efficiency increases with increasing rainfall and is influenced by crop rotation. Under rainfed conditions, modest N losses by volatilization can occur. Leaching losses are usually minimal. Phosphorus use (P) efficiency is higher with band application than with broadcasting. Balanced fertilization, especially involving potassium (K) and micronutrients, is fundamental to efficient nutrient use. Fertilizer efficiency is also influenced by soil test values and agronomic factors that influence crop yields, e.g. sowing date and varietal differences. Rational fertilizer application rates are guided by calibration–response trials. Effective fertilizer use in the region is also dictated by external factors such as government policies and a functioning extension service. In contrast to other regions of the world, environmental impacts from the overuse of fertilizers are relatively minor, while developments in fertilizer formulations that promote efficiency have yet to have impact. Despite the relatively low fertilizer use intensity in dryland areas such as the WANA region, the FBMP comprehensive approach is a logical framework within which to achieve the most efficient management and use of fertilizer in the region’s agriculture. 相似文献
48.
Marcus?Schmidt Kerstin?Sommer Wolf-Ulrich?KriebitzschEmail author Hermann?Ellenberg Goddert?von?Oheimb 《European Journal of Forest Research》2004,123(2):167-176
The endozoochorous and epizoochorous dispersal of vascular plant species by roe deer (Capreolus capreolus) and wild boar (Sus scrofa) was investigated in forest areas of Schleswig-Holstein and Lower Saxony, Germany. The primary aim of this study was to learn about which plant species and in what numbers diaspores are dispersed by the two wild ungulate species. In particular, the significance of zoochory for species composition and biodiversity of forests was evaluated. Fresh faecal pellets were collected from April–November 2001 in the forests of the two study areas. In addition, the coats and hooves of shot roe deer and wild boar were brushed out. The number of viable seeds was determined by greenhouse germination (seedling emergence method). The samples were spread in trays over sterilized soil from the study forests and were kept under controlled conditions in the greenhouse for 12 months. A total of 2,473 individuals from 77 vascular plant species were recorded. While roe deer exceeded wild boar concerning seed contents in the faeces, the significance of roe deer for epizoochorous dispersal was relatively low compared with wild boar. An analysis of the habitat preference of the vascular plant species dispersed by the two ungulate species revealed a high proportion of species growing in forests as well as in the open landscape, and also of non-forest species, while woody plants and herbaceous species closely tied to forest habitats were severely underrepresented. We also discuss consequences for forest ecology and nature conservation. 相似文献
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小反刍兽疫(Peste des petits ruminants,PPR)是山羊、绵羊等小反刍兽类的急性接触传染性疾病,国际上将小反刍兽疫归为A类传染病.目前除非洲、中东和南亚次大陆传播外,在我国周边地区的许多国家和地区也频繁出现流行.因此,该病作为一种重大的跨国动物疫病,也在开始危害我国西藏和其他地区的动物生产和卫生安全[1-2]. 相似文献