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101.
Ernest Arthur Kendall (1876-1938), whose father founded the first veterinary school in Australia, qualified as a veterinary surgeon, as did three of his brothers. He was commissioned in the Australian Army Veterinary Corps and fought with distinction in both the Boer War and World War I. He established an Australian Veterinary Hospital near Calais, France, in 1917. The Purple Cross Society of Victoria paid for the fit-out and necessary material for the running of the hospital, which treated 24,300 animals before it closed in 1919. In that year, Colonel Kendall resumed his career in the Department of Agriculture Victoria, where he was appointed Chief Veterinary Officer in 1926 and Chairman of the Milk Board in 1934. He worked toward a pure milk supply, enabled the establishment of a laboratory to test milk samples, and looked forward to a well-planned campaign for the eradication of bovine tuberculosis.  相似文献   
102.
103.
An in vitro propagation protocol is described for western hemlock, an important forestry species in Canada. For shoot bud induction, embryonic explants were placed initially on one-third strength Schenk and Hildebrandt medium containing 5 M N6-benzyladenine (BA) or 5 M BA in combination with either 5 M kinetin or 5 M 2-isopentenyl adenine for 14 days. The explants were transferred to basal medium without cytokinins for 3 weeks, and then to basal medium containing 0.05% activated charcoal. Elongating shoots were subcultured every 4 weeks on charcoal medium. Shoots, 10 mm in stem height, were rooted either in agar or sterilized peat/perlite (1:1). Up to 70% of the shoots formed roots when they were transferred to the latter, moistened with 1/2 strength Gresshoff and Doy medium containing 5 M -naphthaleneacetic acid. About 90% of the plantlets survived transfer to greenhouse conditions.  相似文献   
104.
Large-scale reforestation programmes are a major source of unwarranted gene flow and can have profound consequences on local genetic diversity. Recently, ash has been introduced to Ireland from continental Europe to stock plantations but has often exhibited poor stem form. It was not known whether these trees were Fraxinus excelsior, Fraxinus angustifolia or interspecific hybrids that are known to occur in continental Europe. F. excelsior is the only native ash in Ireland, so the introduced populations represent a potential threat for the genetic diversity of native populations. We characterized the introduced trees within two plantations (Clonee and Kildalkey) using morphological characters and six microsatellite markers. Samples from continental Europe were included for comparison. Plantations exhibited higher genetic diversity than control populations because our data suggest they contain a mixture of several provenances. There was a small but significant differentiation between plantations and control populations (ФCT = 0.0211). Bayesian analysis to infer population structure and to assign introduced individuals to reference populations clearly demonstrated the presence of hybrid individuals within the plantations. The percentage of trees detected with potential hybrid origin ranged from 28 to 58 % depending on the plantation and the threshold data analysis level chosen. Most hybrids could be considered cryptic because there was a lack of intermediate morphology for hybrid individuals that mainly clustered with F. excelsior. The results indicated that the source of material at the two plantation sites differed. Management options to minimize the impact of these introduced populations are discussed.  相似文献   
105.
106.
Nineteen axial pattern skin flaps were used in 16 dogs and cats to provide skin for repair of extensive cutaneous defects. Retrospective evaluation of medical records was used to determine percentage flap survival, postoperative complications, and long-term outcome of axial pattern skin flaps. The most common indication for use of axial pattern flaps was to augment wound closure following tumor resection (n = 7). Other indications included trauma (n = 5), chronic nonhealing wounds (n = 4), urine-induced cellulitis (n = 1), idiopathic dermal necrosis (n = 1), and chronic lymphoplasmocytic dermatitis (n = 1). Mean flap survival (+/- SD) was 96% (+/- 8). Postoperative complications included wound drainage (n = 15), partial dehiscence of the sutured flap (n = 7), distal flap necrosis (n = 6), infection (n = 3), edema (n = 3), and seroma formation (n = 2). After a median follow-up time of 5 months, evaluation of animals indicated that surgery provided successful wound reconstruction with good cosmetic results. Reconstruction of large cutaneous defects is facilitated by axial pattern flap application regardless of cause of wound. Postoperative complications are common but amenable to standard wound management techniques such as drain placement and surgical debridement of devitalized distal flap skin.  相似文献   
107.
从全球范围来看,家禽饲料的霉菌毒素污染发生率似乎在不断地提高。这对家禽是一个严重的威胁,因为复杂的家禽日粮对霉菌毒素的污染高度易感。因此,此类污染会严重影响家禽的生产性能,由此需要采取适当措施将该损失降低到最小程度。  相似文献   
108.
苜蓿品种对蓟马的抗性评价   总被引:2,自引:3,他引:2  
在2龄和3龄二茬开花初期,调查了蓟马对来自国内外97个苜蓿品种(品系)的危害。调查结果为:蓟马在各品种上的普遍率为100%,有干枯叶片的枝条比率最大67.1%,最小为0,平均为24.3%;运用欧氏完全连锁聚类分析,供试品种对蓟马抗性可分为5个类群,抗虫性最强的品种14个(中兰1号、QS-2、大郁山、润布勒和公农2号等)、抗虫性较强的品种29个(庆阳、SA32140、YL-21、SM9808和陇中等)、抗虫性中等的品种32个(Sceptre、SA32152、阿尔冈金、金皇后和SM9809等)、抗虫性较弱的品种19个(SA16465、SA16464、SA10125、SA7090和苜蓿女王等)和抗虫性最弱的品种3个(来自中国农科院草原研究所的新疆大叶,Wl320、SA35095),5个类群的品种数分别占品种总数的14.4%,29.9%,33.0%,19.6%和3.1%。  相似文献   
109.
In order to evaluate whether infection with E. canis alters the expression of major histocompatibility complex (MHC) class I and/or MHC class II receptors, and by doing so alters the immune response to the organism, flow cytometry was performed on DH82 cells infected with Ehrlichia canis (90% infection) and on uninfected DH82 cells of the same passage, using anti-canine MHC class I and II antibodies. MHC class II expression was evident in 47.6 and 46.2% (mean 46.9%) of uninfected DH82 cells using two different anti-MHC class II antibodies, while no MHC class II expression was evident in DH82 cells infected with E. canis. The present results indicate that infection of DH82 macrophages with E. canis down-regulates their MHC class II receptors. These results suggest a possible mechanism by which E. canis evades the immune system.  相似文献   
110.
The development pathway for tropical livestock production for many years in the twentieth century was to upgrade or replace indigenous stock with exotics of supposedly higher genetic merit. Early indications that this might not be the most appropriate approach were largely ignored. Later there was a reverse movement towards locally developed species and breeds. These were seen as pools of irreplaceable genetic material of unacknowledged merit and value that must not be lost but must be conserved for possible unknown unseen future use. This paper examines the use of various native species and breeds. It goes on to describe some attempts at the introduction of genetically engineered highly productive (at least in their areas of origin) stock. Examples of attempts to produce cross or synthetic breeds are then provided. In a last section the case for the right animal in the right place - and these may be unconventional species and breeds - is provided.  相似文献   
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