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51.
利用新疆已有的丰富核桃资源,高接黑核桃优良无性系,在南北疆建立黑核桃无性系种子园或采穗圃,通过自己采收种子播种育苗,可有效地降低黑核桃苗木生产成本,提高苗木质量,加快黑核桃良种苗木的繁育速度,实现黑核桃良种在新疆的推广、发展。  相似文献   
52.
Twelve varieties of cocksfoot, Dactylis glomerata L., were analysed for three mineral elements (Na, K, Ca) and their dry matter (DM) yields were measured in pot and field trials. Among these characteristics there were strong varietal differences in Na concentration, whereas in other cases the varietal differences were less significant. The concentrations of individual mineral elements were, in most cases, independent of yield and of one another.
Parent plants and their clonal derivatives were highly correlated in Na and Ca concentration as well as in DM yield. Tiller size or position on the parental plant had no significant effects on the mineral concentrations or DM yields of clones derived from separated tillers.
Within varieties continuous variation was observed for Na concentration and the range of variation increased with increasing mean Na concentration. When plants were grown under different experimental conditions there was a high repeatability in Na concentration within varieties over cuts and years. This result was taken as an indication of a strong genetic basis for Na concentration. The results obtained in this study show that it is possible to develop grass varieties of defined potential Na concentration.  相似文献   
53.
为建立特异性和敏感性高的检验犬细粒棘球绦虫感染的方法。用细粒棘球绦虫(简称,Eg)成虫抗原分别免疫兔和绵羊,收集高免血清,纯化的高免抗体。依据抗体夹心ELISA工作原理,以兔抗体包被,检测感染Eg、不同犬带科绦虫的实验犬和空白犬粪样,绵羊抗体扑捉抗原,HRP标记兔抗绵羊IgG(1∶8 000)催化显色,用酶标仪测定OD 405nm吸光度,用以确定其特异性和敏感性。试验结果表明,敏感性为82.69%(43/52),特异性为85.88%(140/163);粪抗原在感染细粒棘球绦虫16d后可检出,最低抗原浓度为9.7ng/mL即犬感染5条成虫时可检测出阳性。该检测方法具有较好的特异性和灵敏性,为进一步研制检测细粒棘球绦虫虫体抗原ELISA检测试剂盒奠定了基础。  相似文献   
54.
Harvest impacts on soil carbon storage in temperate forests   总被引:1,自引:0,他引:1  
Forest soil carbon (C) storage is a significant component of the global C cycle, and is important for sustaining forest productivity. Although forest management may have substantial impacts on soil C storage, experimental data from forest harvesting studies have not been synthesized recently. To quantify the effects of harvesting on soil C, and to identify sources of variation in soil C responses to harvest, we used meta-analysis to test a database of 432 soil C response ratios drawn from temperate forest harvest studies around the world. Harvesting reduced soil C by an average of 8 ± 3% (95% CI), although numerous sources of variation mediated this significant, overall effect. In particular, we found that C concentrations and C pool sizes responded differently to harvesting, and forest floors were more likely to lose C than mineral soils. Harvesting caused forest floor C storage to decline by a remarkably consistent 30 ± 6%, but losses were significantly smaller in coniferous/mixed stands (−20%) than hardwoods (−36%). Mineral soils showed no significant, overall change in C storage due to harvest, and variation among mineral soils was best explained by soil taxonomy. Alfisols and Spodosols exhibited no significant changes, and Inceptisols and Ultisols lost mineral soil C (−13% and −7%, respectively). However, these C losses were neither permanent nor unavoidable. Controls on variation within orders were not consistent, but included species composition, time, and sampling depth. Temporal patterns and soil C budgets suggest that forest floor C losses probably have a lesser impact on total soil C storage on Alfisols, Inceptisols, and Ultisols than on Spodosols, which store proportionately large amounts of C in forest floors with long C recovery times (50–70 years). Mineral soil C losses on Inceptisols and Ultisols indicate that these orders are vulnerable to significant harvest-induced changes in total soil C storage, but alternative residue management and site preparation techniques, and the passage of time, may mitigate or negate these losses. Key findings of this analysis, including the dependence of forest floor and mineral soil C storage changes on species composition and soil taxonomic order, suggest that further primary research may make it possible to create predictive maps of forest harvesting effects on soil C storage.  相似文献   
55.
Abstract

CASE HISTORY: Outbreaks of mortality in South Island saddlebacks (Philesturnus carunculatus carunculatus) that had been translocated to two offshore islands in the Marlborough Sounds of New Zealand were investigated during the summer of 2002 and 2007. Both outbreaks were associated with a severe decrease in numbers of saddlebacks of up to 60% of approximately 200 birds.

CLINICAL AND PATHOLOGICAL FINDINGS: Many of the surviving birds were in poor condition, and had skin lesions on the legs and head. Necropsy showed pale liver and lungs, and a swollen spleen. Histopathology revealed schizonts resembling Plasmodium spp. within the cytoplasm of many hepatocytes and splenic histiocytes. The skin lesions consisted of epithelial proliferations containing numerous Bollinger bodies typical of avipox virus (APV) infection. Two different APV were isolated, using PCR, from two different birds exhibiting skin lesions. Each isolate had 100% sequence homology with APV members from either Clade A or Clade B. In addition, PCR analysis revealed that the Plasmodium elongatum present in infected birdsbelonged to a strain that was endemic in the population of North Island saddlebacks (Philesturnus carunculatus rufusater).

DIAGNOSIS: Concurrent infections with Plasmodium spp. haemoparasites and APV were identified as the likely cause of death in the birds examined.

CONCLUSIONS AND CLINICAL RELEVANCE: Although the Plasmodium spp. identified is thought to be endemic to saddlebacks in New Zealand, the affected birds were likely to be immunocompromised by concurrent APV infection or through lack of genetic diversity. Both the introduced mosquito Culex quinquefasicatus and the native mosquito Culex pervigilans are likely vectors for both these diseases, and the provision of water supplies less favourable to mosquito-breeding is recommended.  相似文献   
56.
This case report describes the accidental intramuscular administration of 20 mL Gudair® vaccine to a 7‐year‐old Standardbred mare and successful treatment of the resulting inflammatory reaction by radical surgical resection.  相似文献   
57.
AIMS: To determine levels of remuneration for veterinarians in New Zealand, to examine associations between putative explanatory factors and gross annual remuneration, and to quantify the type and prevalence of vacant positions.

METHODS: A postal survey to 486 identifiable clinical practices and 53 identifiable organisations that employ veterinarians was used to gather data for the 2-month period of December 2001 to January 2002.

RESULTS: Data were produced for 972 veterinarians (367 females and 605 males) working in 325 clinical practices, and 299 veterinarians (88 females and 211 males) employed by 32 organisations.

Median levels of gross annual remuneration for assistants, partners/shareholders and sole owners working ≥ days per week in clinical practice were NZ$60,000, $90,000 and $75,000, respectively, and for veterinarians in organisations, irrespective of number of days per week worked, was $68,000. Pay rates increased linearly as the number of years since graduation increased for all clinicians and with increasing age for veterinarians in organisations. Full-time assistants were likely to be paid more if the practice was rural rather than urban in location, if they were males, and if administrative duties were part of the job.

The same factors, except for sex, were significant for remuneration for owners and partners/shareholders working full-time. Their remuneration tended to be higher if the practice was involved with either dairy or deer work but decreased as the number of animal species serviced increased and if they worked >5 days per week. Part-time female veterinarians were generally paid more than male counterparts.

Male veterinarians working in organisations were generally paid about 8% more than their female colleagues. Veterinarians in organisations involved with administration at a head office were generally better paid than those without administrative duties. Pay rates were, on the whole, better in private organisations than in universities, state-owned enterprises, government-operated and other types of organisations

About 50% of all services provided by clinical practices were directed to small animals, 27% to dairy cattle and about 10%, 6% and 3% to horses, sheep and beef cattle, and deer, respectively. About 31% of veterinarians worked solely with small animals but most had multiple species workloads.

Of the 325 respondent practices, 98 reported vacancies for 119 veterinarians, of which 79 were full-time, 27 part-time and 12 locum positions. Of the 32 respondent organisations, seven reported vacancies for 16 mostly full-time positions. Farmer-owned co-operative practices were less likely than privately-owned practices to have full-time vacant positions. The only factor identified as influencing part-time vacancies in clinical practices was hourly pay rate. Vacancies occurred randomly across practices, irrespective of location, and there was no indication of greater demand for services for any particular species. The odds of a vacancy in organisations was lower for state-owned enterprises and private organisations than for government organisations (odds ratios (OR)=0.14 and 0.18, respectively).

CONCLUSIONS: Relatively more females than males worked part-time and 23% of all assistants in clinical practice worked part-time. Sex made a significant difference to gross remuneration for full-time assistants in clinical practice and for veterinarians employed by private or government organisations. In both situations, males were generally better paid than females. Female part-time assistants and partners/shareholders or sole owners in clinical practice were generally better rewarded than their male counterparts. Sex had no effect on remuneration levels for owners/partners working full-time in clinical practices.

The study confirmed a serious shortage of veterinarians in New Zealand. The probability of a vacancy occurring in farmer-owned co-operative (‘club’) practices was lower than in private practices. Vacancies were distributed randomly among rural, urban and rural/urban practices with no evidence of rural practices being more severely affected than urban or rural/urban practices.  相似文献   
58.
Epizootics of sudden death in tammar wallabies (Macropus eugenii) occurred at six research facilities and zoological gardens in New South Wales, Australia, in late 1998 and at one Queensland research facility in March 1999. There were 120 confirmed tammar wallaby deaths during this period; however, population censuses indicated that up to 230 tammar wallabies may have died. The majority of animals died without premonitory signs. A small proportion of wallabies exhibited increased respiratory rate, sat with a lowered head shortly before death or were discovered in lateral recumbency, moribund and with muscle fasciculations. Gross postmortem findings consistently included massive pulmonary congestion, mottled hepatic parenchyma and subcutaneous oedema throughout the hindlimbs and inguinal region. Approximately 30% of the animals examined also had extensive haemorrhage within the fascial planes and skeletal muscle of the hindlimb adductors, inguinal region, ventral thorax, dorsal cervical region and perirenal retroperitoneal area. The tissues of affected animals became autolytic within a short period after death. Bacteriological examination of tissues from 14 animals did not provide any significant findings. Toxicological examination of the gastric and colonic contents of four animals did not reveal evidence of brodifacoume or other rodenticides. Viruses from the Eubenangee serogroup of the Orbivirus genus were isolated from the cerebral cortex of nine, and the myocardium of two, tammar wallabies and the liver and intestine of another tammar wallaby. A similar orbivirus was also isolated from the cerebrospinal fluid of another tammar wallaby that died suddenly. The disease agent appears to be a previously unrecognised orbivirus in the Eubenangee serogroup. This is the first report of epizootics of sudden deaths in tammar wallabies apparently associated with an orbivirus infection.  相似文献   
59.
Adverse reactions to intramuscular injections of procaine penicillin G are reported in 11 horses, five of which died. The clinical findings are presented and suggest central nervous involvement in most cases. Post mortem findings in one horse were consistent with anaphylaxis whereas in other cases the clinical findings, duration of treatment, speed of onset and subsequent completion of treatment supports diagnosis of an acute procaine toxicity syndrome.  相似文献   
60.
Sarcoptic mange in wombats   总被引:1,自引:0,他引:1  
  相似文献   
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