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71.
Norris CR Williams BJ Ling GV Franti CE Johnson Ruby AL 《Journal of the American Animal Hospital Association》2000,36(6):484-492
Laboratory records of bacterial urine cultures from 383 dogs with recurrent or persistent urinary tract infections (UTI) diagnosed at the University of California Veterinary Medical Teaching Hospital (VMTH) between 1969 and 1995 were reviewed retrospectively to characterize the bacteria involved and their association with age, gender, and breed of dogs affected. Sixty-eight breeds and a mixed-breed group were represented. Escherichia coli was the most common isolate, although mixed-bacterial infections were seen in 58% of the female and 55% of the male dogs. Recurrent and persistent UTI were most prevalent in middle-aged to older German shepherd dogs, miniature/toy poodles, and Labrador retrievers, with no apparent sex predilection. Criteria fitting recurrent and persistent UTI were present in 0.3% of all dogs seen at the VMTH during this 26-year period. 相似文献
72.
Williams DL 《Veterinary journal (London, England : 1997)》2000,160(1):61-73
The European honey bee (Apis mellifera) has the unusual status of being an inherently wild species from which a natural foodstuff (honey) is derived by manipulating its behaviour to deposit this in man-made wooden frames. Bees also produce propolis and Royal Jelly which can be harvested but their most important effect is one not immediately obvious as an economic product: that of pollination. Bee diseases are predominantly infectious and parasitic conditions accentuated by the close confinement in which they congregate, either in man-made hives or in colonies in a natural cavity. Treatment or at least control of some of these conditions can be attempted. In some cases natural bee behavioural traits limit the effect of the disease while in others, such as the notifiable disease American foulbrood, destruction of the colony is the only method of control. The mite Varroa jacobsoni can be controlled by the synthetic pyrethroids flumethrin and tau-fluvalinate. The introduction of these products has heightened veterinary interest in this important invertebrate species. 相似文献
73.
通过三个试验测定日粮中植酸酶、过量的锌及两者共同对哺乳仔猪的影响。在所有的试验中,每个处理组有5~7栏,每栏有6~7头猪,当日粮中添加植酸酶时,则日粮中钙和有效磷的水平降低0.1%,锌是通过氧化锌的形式添加,试验日粮中含锌水平均为127mg/kg,本试验的周期为19~21d。在试验1中,试验采用2×3因子试验设计,两个水平的植酸酶(即0和500植酸酶单位/kg)和三水平过量的锌(即0,1000和2000mg/kg)。仔猪(5.7kg和18日龄)被随机分配采食以上日粮。试验表明,平均日增重(ADG)和平均日采食量(ADFI)随日粮中锌含量的增加而线性增加,第一阶段为(P=0.01~0.06),第二阶段为(P=0.02~0.09),整个试验阶段为(P=0.01~0.02),肉料比(G∶F)也随日粮锌含量的增加而线性增加,但仅限于第一阶段(P=0.01)。当仔猪采食1000或2000mg/kg锌时的同时添加植酸酶可降低第二阶段ADG(锌与植酸酶互作;P=0.10),但对整个试验周期内ADFI没有影响(P=0.27~0.62),并可降低第二阶段G∶F(P=0.01),及整个试验周期内G∶F(P=0.07)。随着日粮锌添加量的增加,血浆中锌含量也随之增加(Zn2,P=0.01),并且不受植酸酶添加的影响(P=0.70)。在试验2中,试验采用2×2因子试验设计,两个水平的植酸酶(即0和500植酸酶单位/kg)和两水平过量的锌(即0和2000mg/kg)。仔猪(5.2kg和18日龄)被随机分配采食以上日粮。试验表明,日粮中锌含量的增加可使第二阶段ADG和肉料比增加(P=0.02~0.09)和整个试验阶段的ADG和G∶F增加(P=0.07~0.08),但对第一阶段ADG和整个试验阶段ADFI的变化没有影响。植酸酶的添加可增加第二阶段ADG(P=0.06)和G∶F(P=0.01)。当仔猪采食2000mg/kgZn和植酸酶时,G∶F值最大(锌与植酸酶互作;P=0.01)。骨(20日龄)中锌和血浆锌(7和20日龄)随着日粮中锌的添加量的增加而增加(P=0.01),但不受植酸酶添加的影响(P=0.51~0.90)。在试验3中,仔猪(5.7kg和19日龄)被随机分配采食添加500植酸酶单位/kg的植酸酶或不添加植酸酶的基础日粮或添加500植酸酶单位/kg的植酸酶或不添加植酸酶且钙和有效磷含量降低0.10%的基础日粮。试验表明,植酸酶的添加对仔猪生产性能没有影响(P=0.21~0.81)。降低钙和有效磷的含量,可降低整个试验周期内ADG,ADFI和G∶F(P=0.02~0.08)。这些试验结果表明,日粮中添加过量的锌可增加ADG及血浆和骨中锌的浓度。日粮中植酸酶对血浆和骨中锌的浓度没有影响。 相似文献
74.
Michael E. Patterson Jessica M. Montag Daniel R. Williams 《Urban Forestry & Urban Greening》2003,1(3):171-183
Increasing urbanization of rural landscapes has created new challenges for wildlife management. In addition to changes in the physical landscape, urbanization has also produced changes in the socio-cultural landscape. The greater distancing from direct interaction with wildlife in urbanized societies has led to the emergence of a culture whose meanings for wildlife are less grounded in the utilitarian/instrumental orientation of rural agrarian systems. Urban perspectives on wildlife are comprised of more highly individualized emotional/symbolic values. This shift creates two problems with respect to managing wildlife in an urbanizing landscape. First the increased diversity in values and meanings increases the likelihood for social conflicts regarding wildlife management while at the same time making socially acceptable resolutions more intractable. This in turn requires fundamental changes in decision-making paradigms and the research approaches used to inform decision making. Second, as remaining rural communities feel the pressures of urbanization, wildlife conflicts become conflicts not just over wildlife but conflict over larger socio-political concepts such as equity, tradition, private property rights, government control, power, and acceptable forms of knowledge. This paper examines the wildlife management implications of changes associated with increasing urbanization and employs two case studies to illustrate these issues. First a study of a controversy over urban deer management provides insights into how to map conflicting values and search for common ground in an urban culture with increasingly individualistic values for wildlife. Specifically, the analysis illustrates that common ground may, at times, be found even among people with conflicting value systems. The second case study examined a ranching community faced with predator reintroduction. This case study illustrates tensions that occur when the community of interest (i.e. a national public) is broader than the community of place in which the problem occurs. In this latter situation, the debate centers around more than just different views about the rights of animals. It also entailed the rights of individuals and communities to decide their future. The conclusion discusses the need for wildlife institutions to adapt their underlying decision making philosophy including the way science is integrated into decision making processes in light of the changes in social context caused by urbanization. 相似文献
75.
76.
Paracox anticoccidial vaccine was administered to a 7-day-old flock of commercial broiler breeder stock subsequently reared to point-of-lay in the same house. For comparison, three subgroups of another flock of broiler breeders were also vaccinated with Paracox at 7 days of age, reared to 42 days and then transferred to new litter on another farm until point-of-lay. The first subgroup received no further treatment, but the second and third each received a second vaccination with Paracox, either immediately after transfer to the new litter or 42 days after transfer. Using an Eimeria necatrix model, protective immunity was demonstrated by virulent challenge of samples of birds from all groups by the age of 37–40 days (30–33 days after the first vaccination), and was maintained to at least 122–125 days of age, whether the birds remained on the same litter or were transferred to another farm, and whether they received one or two anticoccidial vaccinations. Therefore, there is no disadvantage in transferring birds onto new litter 35 days after a single Paracox vaccination, nor is there any advantage in giving a second vaccination after such a transfer. Vaccinated birds seeded the new litter with oocysts, despite being clinically immune to coccidiosis. A supplementary laboratory experiment showed that birds vaccinated at 8 days of age passed almost no oocysts after a second vaccination at 43 days of age. This indicated that they were not only protected against clinical coccidiosis, but were almost solidly immune to a homologous infection 5 weeks after a single vaccination. Nevertheless, oocysts appeared in the litter of all four groups of commercial breeders throughout the trial, showing that wild-type heterologous infections occurred whether the birds were transferred to new litter or not, but these did not overwhelm the acquired protective immunity and cause clinical coccidiosis. 相似文献
77.
78.
Fine-scale vegetation patches decline in size and cover with increasing rainfall in Australian savannas 总被引:5,自引:0,他引:5
Ludwig John A. Tongway David J. Eager Robert W. Williams Richard J. Cook Garry D. 《Landscape Ecology》1999,14(6):557-566
Fine-scale vegetation patches (<5 m in width) are critically important in many landscapes because they function to obstruct surface flows of water and wind. These obstructions increase the infiltration of runoff and the capture of nutrients in runoff sediments and in wind-blown soil and litter. The importance of redistribution of runoff into runon patches from spaces between patches (fetches) is likely to be greater in drier than in wetter environments. In this paper we examine the hypothesis that the ratio of fetch to patch decreases as rainfall increases, and that this trend will be most evident on intermediate-textured soils because these soils are more prone to runoff. We measured fine-scale patches on 38 sites with sand, loam or clay soils. Sites were located along a 1000-mm rainfall gradient in the savannas of northern Australia. The width and intercept length of patches and the fetch between patches was measuring along line transects of 100–120 m oriented down slope. We found that the ratio of fetch to patch area did not decrease with decreasing rainfall, but increased on both sand and loam soils. This result was because with increasing rainfall mean spacing between patches disproportionally increased while mean patch size and cover declined. The cover of patches was negatively correlated with tree canopy cover, which significantly increased with rainfall. This negative correlation suggests that in higher rainfall savannas the size and spacing of ground-layer patches is controlled by the tree layer, and that as rainfall decreases this control decreases and runoff-runon processes increasingly structure the landscape. For savannas on clay soils these trends were not significant except that on the highest rainfall sites the cover of ground-layer patches was nearly 100% while trees were absent. 相似文献
79.
Williams LE Gliatto JM Dodge RK Johnson JL Gamblin RM Thamm DH Lana SE Szymkowski M Moore AS;Veterinary Cooperative Oncology Group 《Journal of the American Veterinary Medical Association》2003,223(6):825-831
OBJECTIVE: To characterize the signalment, clinical signs, biological behavior, and response to treatment of carcinoma of the apocrine glands of the anal sac in dogs. DESIGN: Retrospective study. ANIMALS: 113 dogs with histologically confirmed carcinoma of the apocrine glands of the anal sac. PROCEDURE: Data on signalment, clinical signs, and staging were reviewed and analyzed along with treatment modality for potential association with survival time. RESULTS: Sex distribution was approximately equal (54% female, 46% male). One hundred four dogs underwent treatment consisting of surgery, radiation therapy, chemotherapy, or multimodal treatment. Median survival for treated dogs was 544 days (range, 0 to 1,873 days). Dogs treated with chemotherapy alone had significantly shorter survival (median, 212 days) than those receiving other treatments (median, 584 days). Dogs not treated with surgery had significantly shorter survival (median, 402 days) than those that underwent surgery as part of their treatment (median, 548 days). Dogs with tumors > or = 10 cm2 had significantly shorter survival (median, 292 days) than dogs with tumors < 10 cm2 (median, 584 days). Hypercalcemia was identified in 27% (n = 29) of dogs, and those dogs had significantly shorter survival (median, 256 days), compared with those that were normocalcemic (median, 584 days). Dogs with pulmonary metastasis had significantly shorter survival (median, 219 days) than dogs without evidence of pulmonary metastasis (median, 548 days). CONCLUSIONS AND CLINICAL RELEVANCE: Unlike most previous reports, this study revealed an approximately equal sex distribution, and results suggest a more favorable prognosis. 相似文献
80.
Williams JH Van Wilpe E Momberg M 《Journal of the South African Veterinary Association》2005,76(2):90-98
A 14-year-old lioness, originating from Etosha in Namibia, and a member of a pride in Pilanesberg National Park since translocation in 1994, was euthanased due to fight-related vertebral fracture and spinal injury, incurred approximately 6-8 weeks previously. Blood specimens collected at the time of death showed mild anaemia and a leukogram reflecting stress and chronic infection. Necropsy conducted within 2 hours of death was on a dehydrated, emaciated animal with hindquarter wasting and chronic traumatic friction injuries from dragging her hindlegs. There was cellulitis in the region of bite-wounds adjacent to the thoraco-lumbar vertebral fracture, at which site there was spinal cord compression, and there was marked intestinal helminthiasis. The outer renal medullae appeared pale and waxy and the liver was macroscopically unremarkable. Histopathology and electron microscopy of the kidneys revealed multifocal to coalescing deposits of proximal medullary interstitial amyloid, which fluoresced strongly with thioflavine T, and was sensitive to potassium permanganate treatment prior to Congo Red staining, thus indicating inflammatory (AA) origin. There was diffuse hepatocyte dissociation, as well as numerous binucleated and scattered multinucleated (up to 8 nuclei/cell) hepatocytes, with swollen hepatocyte mitochondria, in liver examined light microscopically. Ultrastructurally, the mono-, bi- and multinucleated hepatocytes contained multifocal irregular membrane-bound accumulations of finely-granular, amorphous material both intra-cytoplasmically and intra-nuclearly, as well as evidence of irreversible mitochondrial injury. The incidence and relevance in cats and other species of amyloidosis, particularly with renal medullary distribution, as well as of hepatocyte dissociation and multinucleation, as reported in selected literature, is briefly overviewed and their occurrence in this lioness is discussed. 相似文献