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Maes D Gibson K Trigo E Saszak A Grass J Carlson A Blaha T 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(9-10):339-341
This field study investigated the efficacy of a Salmonella Choleraesuis live vaccine (Argus SC) to reduce the number of infections with Salmonella. Twelve groups of about 380 pigs each were randomly allocated to either vaccination (V) or no vaccination (C). The vaccine was applied orally at 3 and 16 weeks. Forty pigs per group were blood sampled at 3, 10, 16, and 24 weeks to detect possible antibodies against Salmonella. The prevalence of Salmonella in the lymph nodes was the major variable. In the V groups, only 0.6% of the lymph nodes were positive, whereas 7.2% were positive in the C groups (p < 0.001). The percentage of seropositive pigs at 24 weeks (cut-off OD > 10) was 26% and 9% in the V and C groups, respectively (p < 0.001). The present study documented that vaccination with a live modified S. Choleraesuis vaccine is a useful tool to lower the prevalence of Salmonella in swine herds. 相似文献
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Pusterla N Watson JL Affolter VK Magdesian KG Wilson WD Carlson GP 《The Veterinary record》2003,153(4):118-121
The medical records of 53 horses with purpura haemorrhagica were reviewed. Seventeen of them had been exposed to or infected with Streptococcus equi, nine had been infected with Corynebacterium pseudotuberculosis, five had been vaccinated with S. equi M protein, five had had a respiratory infection of unknown aetiology, and two had open wounds; the other 15 cases had no history of recent viral or bacterial infection. The horses were between six months and 19 years of age (mean 8.4 years). The predominant clinical signs were well demarcated subcutaneous oedema of all four limbs and haemorrhages on the visible mucous membranes; other signs included depression, anorexia, fever, tachycardia, tachypnoea, reluctance to move, drainage from lymph nodes, exudation of serum from the skin, colic, epistaxis and weight loss. Haematological and biochemical abnormalities commonly detected were anaemia, neutrophilia, hyperproteinaemia, hyperfibrinogenaemia, hyperglobulinaemia and high activities of muscle enzymes. All of the horses were treated with corticosteroids; 42 also received non-steroidal anti-inflammatory drugs and 26 received antimicrobial drugs. Selected cases received special nursing care, including hydrotherapy and bandaging of the limbs. Most of the horses were treated for more than seven days and none of them relapsed. Forty-nine of the horses survived, one died and three were euthanased, either because their severe clinical disease failed to respond to treatment or because they developed secondary complications. Two of the four non-survivors had been vaccinated against S. equi with a product containing the M protein, one had a S. equi infection and the other had a respiratory infection of undetermined aetiology. 相似文献
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McKenzie EC Valberg SJ Godden SM Pagan JD Carlson GP MacLeay JM DeLaCorte FD 《American journal of veterinary research》2002,63(7):1053-1060
OBJECTIVE: To determine whether plasma, urine, and fecal electrolyte and mineral concentrations differ between clinically normal horses and Thoroughbreds with recurrent exertional rhabdomyolysis (RER) after consumption of diets varying in cation-anion balance. ANIMALS: 5 Thoroughbred mares with RER and 6 clinically normal mixed-breed mares. PROCEDURE: Each of 3 isocaloric diets designated as low, medium, and high on the basis of dietary cation-anion balance (DCAB) values of 85, 190, and 380, respectively, were fed to horses for 14 days. During the last 72 hours, 3 horses with RER and 3 control horses had daily urine and fecal samples obtained by total 24-hour collection. Remaining horses had urine samples collected daily by single catheterization. RESULTS: For each diet, no differences existed between horses with RER and control horses in plasma pH, electrolyte concentrations, and creatine kinase activity or in urine pH and renal fractional excretion (FE) values. Plasma pH, strong ion difference, bicarbonate and total carbon dioxide concentrations, and base excess decreased and plasma chloride and ionized calcium concentrations increased with decreasing DCAB. Urine pH decreased with decreasing DCAB. The FE of chloride and phosphorus were greatest for horses fed the low diet. The FE values for all electrolytes exept magnesium did not differ between urine samples obtained by single catheterization and total 24-hour collection. Daily balance of calcium, phosphorus, sodium, chloride, and potassium did not differ significantly among horses fed the various diets. CONCLUSIONS: In clinically normal horses and in horses with RER, the DCAB strongly affects plasma and urine pH and the FE of sodium, potassium, chloride, and phosphorus. 相似文献
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Maleski K Magdesian KG LaFranco-Scheuch L Pappagianis D Carlson GP 《The Veterinary record》2002,151(17):505-508
A 13-day-old foal with profound tachypnoea and respiratory distress was examined. Thoracic radiographs revealed a severe, diffuse miliary pattern, and the foal was markedly hypoxaemic. It failed to improve with empirical treatment, and was euthanased. Lesions associated with Coccidioides immitis infection were identified at postmortem examination, and were limited to the lower respiratory tract. 相似文献
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Schoenmakers I Hazewinkel HA Voorhout G Carlson CS Richardson D 《The Veterinary record》2000,147(23):652-660
The skeletal development of three groups of great dane dogs, fed a diet composed according to the published nutritional requirements for dogs (controls) or with increased calcium or calcium and phosphorus content, was examined radiographically, histologically and biochemically. The diets were fed from the time the dogs first began eating food in addition to their dam's milk, until they were 17 weeks old. Thereafter, the calcium and phosphorus intakes of the dogs in the high calcium groups were normalised for a further 10 weeks. The dogs fed the high calcium diet without a proportionally high phosphorus intake became hypercalcaemic and hypophosphataemic, and had severe disturbances in skeletal development, growth, and mineralisation which were typical for rickets. After their calcium intake was normalised the lesions of rickets resolved but osteochondrotic lesions became apparent. The dogs fed the high calcium and phosphorus diet became slightly hypophosphataemic, their growth was retarded, and they had disturbances in skeletal development resembling osteochondrosis, which had only partly resolved after 10 weeks on the normal calcium and phosphorus diet. 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