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61.
Landscape Ecology - Tritrophic interactions may be affected by local factors and the broader landscape context. At small spatial scales, carnivorous enemies of herbivorous insects use...  相似文献   
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Rhinoceros populations in Africa are under severe threat as a result of surging poaching rates and risk-mitigation strategies are continuously adapted in an attempt to ensure the survival of the species. This study compared faecal glucocorticoid metabolite (fGCM) levels of two age classes of limited free-ranging female white rhinos with fGCM levels of adult free-ranging female white rhinos. Subsequently, fGCM alterations in the limited free-ranging animals were monitored following routine dehorning as a measure of the animals’ short-term physiological stress response. Baseline fGCM levels differed significantly between tested groups, with both free-ranging and limited free-ranging adult animals showing significantly higher fGCM levels compared with limited free-ranging juvenile females. In contrast, baseline fGCM levels did not differ significantly between limited free-ranging and free-ranging adult individuals. Routine dehorning procedures resulted in a short-term stress response expressed by a significant increase in fGCM levels 48 h post-dehorning, with stress steroid levels returning to pre-dehorning concentrations 72 h after the procedure.  相似文献   
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Fifty‐one dairy cows with subclinical ketosis were used to investigate the effects of butafosfan alone or in combination with cyanocobalamin on metabolism. Treatments included i.v. injection of 10 ml/100 kg of body weight with butafosfan (BUT) or combined cyanocobalamin with butafosfan (BUTCO) at a similar concentration as in Catosal®. Control cows (CON) received a 0.9% saline solution. Cows were injected on days 1–3 at 22.3 ± 0.7 days post‐partum. Milk production and composition were not affected by the treatments. In plasma, CON cows had a significantly higher plasma NEFA concentration (0.59 ± 0.03 mm ) across the study period than BUTCO cows (p < 0.05; 0.42 ± 0.03 mm ), whereas the plasma NEFA concentration of BUT was intermediate (0.52 ± 0.03 mm ) but not significantly different from CON. Both BUTCO and BUT cows had lower (p < 0.05) plasma BHBA concentrations (1.02 ± 0.06 mm and 1.21 ± 0.06 mm , respectively) across the study period than CON (1.34 ± 0.06 mm ). Plasma glucose was not different between treatments, but plasma glucagon concentrations were consistently high in BUT compared to BUTCO and CON. Lowest post‐treatment glucagon levels were observed in BUTCO. Hepatic mRNA abundance of liver X receptor α, a nuclear receptor protein involved in lipid metabolism, was higher in BUTCO compared to BUT and CON (p < 0.05) on day 7. Furthermore, on day 7, the mRNA abundance of beta‐hydroxybutyrate dehydrogenase 2 was higher in BUTCO compared to BUT and CON (p < 0.01). In conclusion, injections of combined cyanocobalamin with butafosfan post‐partum in early lactation ketotic dairy cows act on lipid metabolism with effects on plasma metabolites, most likely mediated via modified activity of key factors in the liver. Results indicate that the application of butafosfan only in combination with cyanocobalamin exhibits the expected positive effects on metabolism.  相似文献   
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CASE DESCRIPTION: A 6.5-year-old female eastern black and white colobus monkey (Colobus guereza) was evaluated after acute onset of ataxia and inappetence. CLINICAL FINDINGS: The monkey was ataxic and lethargic, but no other abnormalities were detected via physical examination, radiography, or clinicopathologic analyses. During the next 2 days, the monkey's clinical condition deteriorated, and its WBC count decreased dramatically. Cytologic examination of a CSF sample revealed marked lymphohistiocytic inflammation. TREATMENT AND OUTCOME: Despite supportive care, the monkey became apneic; after 20 hours of mechanical ventilation, fatal cardiac arrest occurred. At necropsy, numerous petechiae were detected within the white matter tracts of the brain; microscopic lesions of multifocal necrosis and hemorrhage with intranuclear inclusions identified in the brain and adrenal glands were consistent with an acute herpesvirus infection. A specific diagnosis of herpesvirus papio-2 (HVP-2) infection was made on the basis of results of serologic testing; PCR assay of tissue specimens; live virus isolation from the lungs; and immunohistochemical identification of the virus within brain, spinal cord, and adrenal gland lesions. Via phylogenetic tree analysis, the colobus HVP-2 isolate was grouped with neuroinvasive strains of the virus. The virus was most likely transmitted to the colobus monkey through toys shared with a nearby colony of baboons (the natural host of HVP-2). CLINICAL RELEVANCE: To the authors' knowledge, this is the first reported case of natural transmission of HVP-2 to a nonhost species. Infection with HVP-2 should be a differential diagnosis for acute encephalopathy in primate monkeys and humans, particularly following exposure to baboons.  相似文献   
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Infectious bronchitis (IB) disease progression in vaccinated chickens after challenge was evaluated in a single commercial line of layer chickens presenting two different major histocompatibility complex (MHC) B complex genotypes. MHC B genotypes were determined by DNA sequence-based typing of BF2 alleles. In total, 33 B2/B15 and 47 B2/B21 chickens were vaccinated with an Ark-type IB virus (IBV) attenuated vaccine and challenged with Ark-type IBV field isolate AL/4614/98 14 days later. Additional chickens of both genotypes served as unvaccinated/challenged and unvaccinated/nonchallenged controls. Clinical signs, histopathologic analysis, detection of IBV genomes in tears, and IBV-specific immunoglobulin A (IgA) in tears were used to evaluate disease progression and immune response. The incidence of IBV respiratory signs was significantly higher in B2/21 than in B2/B15 MHC genotype birds. However, neither the severity and duration of respiratory signs nor the severity and incidence of histologic lesions differed significantly with MHC genotype. The levels of IBV-specific IgA in tears of vaccinated and challenged chickens did not differ significantly between MHC genotypes. IBV genomes were present in the tears of vaccinated and challenged birds, and the incidence of detectable IBV genomes did not vary significantly with MHC B genotype. From an applied perspective, these results indicate that vaccinated commercial outbred chickens with these MHC genotypes are equally resistant to IBV.  相似文献   
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