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Camillo F Marmorini P Romagnoli S Cela M Duchamp G Palmer E 《Equine veterinary journal》2000,32(4):307-310
The aim of this study was to test whether low dose oxytocin i.v. injection once a day to mares diagnosed as being ready for birth by mammary secretion calcium strip test measurements could be used as a reliable method to induce parturition and/or predict the mare would not foal during the following night if parturition did not occur within 2 h of treatment. Fifty-one near-term Haflinger mares were used and a single injection of 2.5 iu oxytocin was given between 1700 and 1900 h, including 10 mares used as controls which were administered a placebo. Administration of oxytocin resulted in the delivery of a normal foal within 120 min in 95% of mares. Twenty-four out of 38 (63%) treated animals foaled in response to the first oxytocin injection, 9 out of 38 (24%) in response to the second injection and 3 out of 38 (8%) in response to the third treatment. Two out of 38 (5%) treated mares foaled during the night irrespective of treatment whereas 7 out of 10 (70%) control mares foaled during the night. It was concluded that the major advantage of injecting a daily low dose of oxytocin appears to be that such a low dose induces delivery only in mares carrying a mature fetus and which are ready to foal. 相似文献
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Top 20 environmental weeds for classical biological control in Europe: a review of opportunities, regulations and other barriers to adoption 总被引:4,自引:3,他引:4
Classical biological control remains the only tool available for permanent ecological and economic management of invasive alien species that flourish through absence of their co‐evolved natural enemies. As such, this approach is recognized as a key tool for alien species management by the Convention on Biological Diversity (CBD), the European and Mediterranean Plant Protection Organization (EPPO) and the European Strategy on Invasive Alien Species (ESIAS). Successful classical biological control programmes abound around the world, despite disproportionate attention being given to occasional and predictable non‐target impacts. Despite more than 130 case histories in Europe against insect pests, no exotic classical biological control agent has been released in the EU against an alien invasive weed. This dearth has occurred in the face of increasing numbers of exotic invasive plants being imported and taking over National Parks, forests and amenity areas in this region, as well as a global increase in the use of classical biological control around the world. This paper reviews potential European weed targets for classical biological control from ecological and socioeconomic perspectives using the criteria of historical biological control success, taxonomic isolation from European native flora, likely availability of biological control agents, invasiveness outside Europe and value to primary industry and horticulture (potential for conflicts of interest). We also review why classical biological control of European exotic plants remains untested, considering problems of funding and public perception. Finally, we consider the regulatory framework that surrounds such biological control activities within constituent countries of the EU to suggest how this approach may be adopted in the future for managing invasive exotic weeds in Europe. 相似文献
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Objectives To investigate the use of unguided bronchoalveolar lavage techniques in dogs without fibreoptic bronchoscopy, using an adapted single vascular catheter and a double-lumen catheter made from two single vascular catheters.
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 106 /L was calculated from 57 clinically and histologically normal dogs. The major residual effects of the technique were localised pulmonary oedema, and alveolar distension with collapse and congestion of distant parenchyma. Thoracic radiographs revealed increased lung opacity for at least up to 7 h after the procedure.
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract. 相似文献
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 10
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract. 相似文献
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J J Ettlinger T Ford J E Palmer 《Journal of the American Veterinary Medical Association》1990,196(10):1628-1630
Proximal enteritis was diagnosed on the basis of clinical signs of disease in 2 Standard-bred yearlings from the same farm. Large volumes of fluid were repeatedly obtained during gastric decompression. The horses did not respond to treatment with IV administered fluids, antimicrobial agents, cimetidine, and metoclopramide. Postmortem findings confirmed severe focal chronic active duodenitis with stricture formation. An etiologic agent was not identified. 相似文献
28.
B J Weigler D W Hird W M Sischo J C Holmes C Danaye-Elmi C W Palmer W W Utterback 《Journal of the American Veterinary Medical Association》1990,196(12):1945-1949
Twenty-nine California dairy herds were studied over a 12-month period from 1988 to 1989 as part of the National Animal Health Monitoring System. Monthly interviews administered to dairy producers were used to measure the costs of all health-related expenditures and disease incidence in these herds. Of the total $1,523,558 reported, $1,355,467 (89%) was attributed to cost of disease events and $168,091 (11%) to cost of disease prevention. Most (78%) of the cost of disease events was attributable to death and culling losses. Veterinary services accounted for only $54,099 (4%) of total costs, 64% of which was used for disease prevention, compared with 36% for disease treatment. Udder disease was the most costly category of diseases reported at an average of $49.85/head at risk annually, followed by reproductive problems at $38.05. Through the use of sampling strategies less biased than those used in other surveys, the National Animal Health Monitoring System is designed to provide statistically-valid estimates of disease incidence and costs across broad geographic areas, potentially benefiting all those interested in the economics of livestock diseases in the United States. 相似文献
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R D Jolly R D Martinus A Shimada I M Fearnley D N Palmer 《Canadian journal of veterinary research》1990,54(1):15-21
The pathogenesis of the ceroid-lipofuscinoses, inherited storage diseases of children, was studied in an ovine model. This was shown to have clinical and pathological features most in common with the late infantile and juvenile human forms of the disease. The ability to study sequential changes allowed the retinal lesions to be described as a dystrophy of photoreceptor outer segments which preceded loss of the photoreceptor cells. An early decrease in amplitude of the c-wave electroretinograph was attributed to a decrease in the transpigment epithelial component. The decreased a- and b-wave amplitudes were attributed to the changes in and loss of, photoreceptor cells. The chemical components of isolated storage cytosomes were analyzed and shown to consist mostly of protein. Sequence analysis of the dominantly stored protein showed that it was identical to the DCCD reactive proteolipid or subunit c of mitochondrial adenosine triphosphate synthase and that it comprised approximately 50% of storage material. Based on the adage that the dominantly stored species should reflect the underlying biochemical anomaly, it was concluded that it was of pathogenic significance. This highly hydrophobic protein tends to extract with lipids in chloroform/methanol and is thus known as a proteolipid. Some of the remainder of the stored proteins also had this characteristic. It was concluded that ovine ceroid-lipofuscinosis was a proteinosis, more specifically a proteolipid proteinosis and as such it forms the prototype of a new class of storage diseases. Recognition of the nature of the dominantly stored chemical species has helped understanding of a variety of chemical and physical characteristics attributed to the whole pigment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献