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Some genetic characteristics of the freely drained soils of the ettrick association in East Scotland
This paper describes the interrelated characteristics of the freely drained soil series of the Ettrick Association. These soils are extensively developed in the Southern Uplands of Scotland on glacial drift derived from greywacke.At the present day the soils of the Linhope series are acid brown soils whereas the Minchmoor and Dod series include podzols and peaty podzols. Subalpine podzols and alpine soils are included within the Merrick series. It is concluded that the soils of the Linhope, Minchmoor and Dod series were all formerly brown forest soils under deciduous woodland. They have evolved to their present status after forest clearance which gathered momentum after the widespread establishment of monastic institutions in Scotland in the twelfth and thirteenth centuries A.D. The evolutionary outline of profile development is described and discussed. 相似文献
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M. Arias L. Robertson A. Garcia‐Alvarez S. C. Arcos M. Escuer R. Sanz J. P. Mansilla 《Forest Pathology》2005,35(5):375-383
A survey of the xylophagous insects in the conifer forests, mainly Pinus pinaster woodlands, in Spain was carried out in order to study the phoretic vectors of nematodes of the genus Bursaphelenchus. Fifteen environmental sites were characterized on the bases of altitude, rainfall, temperature and conifer species. Specimens of Orthotomicus erosus (n = 3476) were captured of which 59% carried nematodes under their elytrous, most of them were aphelenchid fungal‐feeding nematodes, but B. fungivorus was found on the beetles from Las Cumbres, Villa Blanca, (Huelva), southern Spain, which represent the first record of O. erosus as vector of a Bursaphelenchus sp. The nematode is characterized by morphometric and biomolecular techniques and distribution and ecology of the insect is discussed. 相似文献
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A VALENTINE‐SHAPED CARDIAC SILHOUETTE IN FELINE THORACIC RADIOGRAPHS IS PRIMARILY DUE TO LEFT ATRIAL ENLARGEMENT 下载免费PDF全文
Trisha J. Oura Aisha N. Young Bruce W. Keene Ian D. Robertson Dennis E. Jennings Donald E. Thrall 《Veterinary radiology & ultrasound》2015,56(3):245-250
Conflicting information has been published regarding the cause of a valentine‐shaped cardiac silhouette in dorsoventral or ventrodorsal thoracic radiographs in cats. The purpose of this retrospective, cross‐sectional study was to test the hypothesis that the valentine shape is primarily due to left atrial enlargement. Images for cats with a radiographic valentine‐shaped cardiac silhouette and full echocardiography examination were retrieved and independently reviewed. A subjective scoring system was used to record severity of radiographic valentine shape. Subjective radiographic evidence of left atrial enlargement in a radiographic lateral projection and a final diagnosis based on medical records were also recorded. A total of 81 cats met inclusion criteria. There was a strong positive correlation (P < 0.001) between echocardiographic left atrial size and severity of radiographic valentine shape. There was no effect of echocardiographic right atrial size on the severity of valentine shape, except when concurrent with severe left atrial enlargement. In this situation, right atrial enlargement increased the likelihood of observing a severe valentine shape. There was no effect of right atrial enlargement on the shape of the cardiac silhouette when left atrial enlargement was absent or only mild to moderate. There was no correlation between the category of final diagnosis of cardiac disease and the severity of valentine shape. Findings from this study supported the hypothesis that a valentine‐shaped cardiac silhouette in radiographs is due primarily to left atrial enlargement in cats, with right atrial enlargement only impacting the shape if concurrent with severe left atrial enlargement. 相似文献
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Suraj Gunawardana Dulari Thilakarathne Indra S. Abegunawardana Preeni Abeynayake Colin Robertson Craig Stephen 《Tropical animal health and production》2014,46(7):1105-1112
A study of the risk factors associated with mastitis in Sri Lankan dairy cattle was conducted to inform risk reduction activities to improve the quality and quantity of milk production and dairy farmer income. A cross-sectional survey of randomly selected dairy farms was undertaken to investigate 12 cow and 39 herd level and management risk factors in the Central Province. The farm level prevalence of mastitis (clinical and subclinical) was 48 %, similar to what has been found elsewhere in South and Southeast Asia. Five cow level variables, three herd level variables, and eight management variables remained significant (p?0.05) in the final logistic regression analysis. Expected risk factors relating to unhygienic environments and inadequate knowledge or practice of mastitis control were found. Other factors included parity, milk yield, milking practices, access to veterinary services, use of veterinary products, stall structure, and stall hygiene. Many of the risk factors could be addressed by standard dairy cattle management techniques, but implementation of mastitis control programs as a technical approach is likely to be insufficient to achieve sustainable disease control without consideration of the social and political realities of smallholder farmers, who are often impoverished. 相似文献