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991.
OBJECTIVE: To examine the effects of euthanasia rates, euthanasia practices, and human resource practices on the turnover rate among employees with euthanasia responsibilities at animal shelters. DESIGN: Cross-sectional original study. SAMPLE POPULATION: 36 shelters across the United States that employed at least 5 full-time employees and performed euthanasia on site. PROCEDURES: By mail, 1 survey was sent to each shelter. Surveys were completed by a senior member of management and were returned by mail. Questions assessed characteristics (eg, euthanasia rates) and practices of the animal shelter, along with employee turnover rates. By use of correlation coefficients and stepwise regression analyses, key predictors of turnover rates among employees with euthanasia responsibilities were investigated. RESULTS: Employee turnover rates were positively related to euthanasia rate. Practices that were associated with decreased turnover rates included provision of a designated euthanasia room, exclusion of other live animals from vicinity during euthanasia, and removal of euthanized animals from a room prior to entry of another animal to be euthanized. Making decisions regarding euthanasia of animals on the basis of factors other than behavior and health reasons was related to increased personnel turnover. With regard to human resources practices, shelters that used a systematic personnel selection procedure (eg, standardized testing) had comparatively lower employee turnover. CONCLUSIONS AND CLINICAL RELEVANCE: Data obtained may suggest several specific avenues that can be pursued to mitigate turnover among employees with euthanasia responsibilities at animal shelters and animal control or veterinary medical organizations.  相似文献   
992.
Sheep and dog blood samples were collected from nine farms in the county of Guarapuava, Paraná, Brazil. The indirect fluorescent antibody test (IFAT) was used to detect Neospora caninum and Toxoplasma gondii antibodies. Herein, serum samples from 305 sheep were evaluated, being 29 (9.5%) and 157 (51.5%) seropositives to N. caninum and T. gondii, respectively. Seven (29.1%) and five (20.8%) out of 24 dogs were seropositives to N. caninum and T. gondii, respectively. There were no differences among the sheep serology for N. caninum and reproductive problems, management and animal feeding variables, neurological problems and presence of other animals species on the farm (P>or=0.05). The simultaneous frequency of antibodies between N. caninum and T. gondii was 5.2% in the herds. Age, breed, farm size, semi-intensive activity, mineral salt supplementation, water origin, stage of the pregnancy when reproduction problems occurred, neurological problems in lambs, presence of rodents in the food room and pasture cat access were identified as associated factors for the occurrence of toxoplasmosis in sheep (P<0.05). There were no differences among the seropositivity in dogs for N. caninum and T. gondii and breed, age and sex (P>or=0.05). The present work is the first report on serum prevalence of N. caninum in sheep from the state of Paraná, Brazil.  相似文献   
993.
Paratuberculosis (PTB) in Brazil has previously only been reported in imported animals and is officially considered as an exotic disease. A dairy herd, which had no imported animals, presented clinically suspect animals and was investigated for paratuberculosis using faecal culture, histopathology, indirect ELISA and the agar gel immunodiffusion test. Infection with Mycobacterium avium subsp. paratuberculosis (Map) was confirmed by culture of faeces from five cows with clinical symptoms of PTB and in 7/24 randomly selected asymptomatic cows from the same herd. Two cows with clinical symptoms were necropsied and their tissues were positive for Map by culture and histopathology. Twelve asymptomatic, randomly selected cows were positive on ELISA. The results confirmed the presence of PTB in this dairy herd and for the first time demonstrated the disease in a herd of native-bred cattle in Brazil.  相似文献   
994.
Fatal cytauxzoonosis is described in a captive reared lioness (Panthera leo) and its 6-month-old cub. Clinical signs in the lioness included loss of weight, depression, anaemia, loss of hair, dark discolored urine, tachypnoea, nystagmus, deaphness and staggering gait. The cub died after a short period of depression. In the lioness, laboratory examination revealed normochromic normocytic anaemia, neutrophilia, lymphopenia, monocytosis, eosinopenia, thrombocytopenia, proteinuria, pyuria, haematuria and increased. At necropsy the lioness showed marked pulmonary edema and slight gelatinous translucent edema in the mediastinum, petechiae and echymosis disseminated in the serosae, and the intestinal content was red and semiliquid. The cub presented hemothorax, endocardial and pulmonary edema, petechiae in the cardiac serosae, hepatic and splenic congestion and segments of the small intestine with blood stained fluid contents and reddish mesenteric lymph nodes. Histopathological examination of liver, spleen, heart, lungs, intestines, pancreas, mesenteric lymph nodes, kidneys, skeletal muscle, brain and skin revealed large number of intravascular macrophages with their cytoplasm filled with various schizogonic stages of a Theileriidae. Electron microscopy confirmed the presence of schizonts in endothelial-associated macrophages. The diagnosis was established by the finding of the pathognomonic schizonts in macrophages within blood vessels in several organs and tissues from both lions. This is the first report of feline cytauxzoonosis in P. leo and of a confirmed infection by Cytauxzoon felis in felidae in South America.  相似文献   
995.
The relationships between climate conditions and wood density in tropical forests are still poorly under-stood. To quantify spatial dependence of wood density i...  相似文献   
996.
We evaluate the feasibility of using foliar-applied molybdenum, (Mo) instead of side-dressed nitrogen (N) in three experiments. In soils with native rhizobia, plants received 0, 30, 60, 90 or 120 kg N ha?1 with +Mo (80 g ha?1) or -Mo. N concentration in leaves (NCL) -Mo ranged from 35.1 to 42.5 g kg?1 and NCL +Mo from 40.3 to 49.2 g kg?1; yield -Mo ranged from 1560 to 3350 kg ha?1and yield +Mo from 2829 to 3567 kg ha?1. In two experiments, NCL or yield -Mo increased linearly or quadratically with increasing N rates, but NCL or yield +Mo did not. In one experiment, NCL increased linearly with increasing N rates and 16% with +Mo relative to –Mo, but yield was not affected significantly. Our results suggest that using Mo fertilizer instead of side-dressed N can allow common bean plants to meet crop demands for N to support yields as high as 3000 kg ha?1.  相似文献   
997.
Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (−)-elatol and (+)-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (−)-elatol showed moderate larvicidal activity, whereas (+)-obtusol presented higher toxic activity than (−)-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+)-obtusol revealed damage to the intestinal epithelium. Moreover, (+)-obtusol-treated larvae incubated with 2 µM CM-H2DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+)-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound.  相似文献   
998.
A comprehensive review on the chemistry of Spongia sp. is here presented, together with the biological activity of the isolated compounds. The compounds are grouped in sesquiterpene quinones, diterpenes, C21 and other linear furanoterpenes, sesterterpenes, sterols (including secosterols), macrolides and miscellaneous compounds. Among other reports we include studies on the intraspecific diversity of a Mediterranean species, compounds isolated from associated sponge and nudibranch and compounds isolated from S. zimocca and the red seaweed Laurentia microcladia. Under biological activity a table of the reported biological activities of the various compounds and the biological screening of extracts are described. The present review covers the literature from 1971 to 2015.  相似文献   
999.
Potential environmental effects of probiotics used in aquaculture   总被引:1,自引:0,他引:1  
Probiotics are a live microbial feed supplement that beneficially affects the host animal. As aquaculture is one of the main areas where probiotics can be applied, the environmental suitability of using probiotics in hatching and nursing facilities for turbot farming was evaluated through the life cycle assessment (LCA) methodology. This LCA study showed that the potential environmental impacts associated with probiotic production are generally offset by the impact reductions linked to lower consumption levels and reduced waste and emission generation rates within the hatching and nursing subsystem. Thus, the use of probiotics is recommended in order to enhance the performance of turbot aquaculture systems provided that operational and economic advantages are attained.  相似文献   
1000.
The effect of the addition of Bacillus probiotic during larvae and postlarvae culture of the white shrimp Litopenaeus vannamei was examined in three separate experiments: (I) Nauplius4‐5 to Zoea3, which were exposed to probiotic in the water (Pw), only in the microalgae (Pm), in the water and microalgae (Pwm) and a control with no probiotic (C); (II) Mysis1 to Mysis3, which were exposed to probiotic in the water (Pw), only in Artemia (Pa), in the water and Artemia (Pwa) and a control (C); (III) PL1 to PL10, which were exposed to similar treatments for mysis experiment. The use of probiotic Bacillus spp. resulted in an increase in the survival and growth of zoea and mysis phases, especially when the probiotic was added only in the water. For postlarvae, the use of the probiotic had no influence on the zootechnical parameters, however, there was a reduction in the count of presumptive Vibrio both for water and shrimp.  相似文献   
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