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Two male North American elk from a commercial herd were evaluated because of a sudden onset of lethargy, anorexia, and voiding of red urine. These 2 elk were kept in the same pen as 4 other male elk that had died during the preceding 2 months. Laboratory analyses revealed anemia and intraerythrocytic parasites, later confirmed as Babesia odocoilei (a protozoal hemoparasite of cervids). Of the 240 elk remaining in the herd, 59 were screened for B odocoilei by microscopic evaluation of blood smears, protozoal culture of blood, and immunofluorescent antibody testing of serum. Of those 59 elk, 34 (58%) were infected with B odocoilei. Babesia odocoilei infection in elk can be fatal and should be considered in cases of sudden death or acute hemolytic anemia. Familiarity with the disease in elk is essential for practitioners because of the increasing popularity of commercial elk farming.  相似文献   
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Monensin, a polyether ionophore antibiotic, is potentially an important agent for bloat relief in dairy cows grazing temperate legume-based pasture. A series of studies was undertaken to determine the effect of monensin, when delivered continuously in the rumen of lactating dairy cows by means of controlled-release capsules (monensin CRC). Such devices release approximately 300 mg/head/day for 100 d. A short-term pilot study made at Ruakura, New Zealand, tested monensin CRC in cows selected for high susceptibility to bloat and grazing lucerne (Medicago sativa) or red clover (Trifolium pratense). Treatment significantly reduced the incidence of bloat, while milk yield and protein yield were increased. There was no effect on fat yield. Following the pilot study, 6 large-scale field experiments involving a total of 368 lactating dairy cows, were made in Australia and New Zealand to confirm the effectiveness of monensin CRC for bloat control and to measure the effect of such treatment on milk production and composition. A severe bloat problem occurred in 2 experiments, mild bloat occurred in 2 others, while no visual signs of bloat were observed in the remaining 2 experiments. Bloat was significantly (P less than 0.05) reduced by monensin CRC treatment when data was pooled over the 4 experiments in which bloat occurred. Daily milk yield was increased in all experiments from a mean of 17.7 in untreated groups to 18.8 kg/head/day (P less than 0.05) in monensin CRC-treated cows. Protein percentage was not affected by treatment, while there was a decrease from 4.29 to 4.10% fat, although total fat yield was not affected.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Cohort studies were conducted on 29 pigs from 3 villages in the Highlands of Papua New Guinea. Animals ranged in age from 9 d to 5 m old. Three hundred and twenty nine faecal samples were collected from individual pigs followed over 3 to 6 w periods, and were examined for group A rotavirus antigen by ELISA, and rotaviral genomic RNA by polyacrylamide gel electrophoresis (PAGE). Electron microscopy was also conducted on selected samples. Group A rotavirus was detected in the faeces of 16 pigs with infected individuals coming from all villages. Non-group A rotavirus resembling group C was found in faeces from pigs from 2 villages. All of the group A rotaviruses examined had the same electrophoretype and this was distinct from that of the common type infecting humans in the area at the time of the study. None of the group A positive samples reacted with monoclonal antisera specific for human group A rotaviruses of serotypes 1, 2, 3, 4, or 8. The non-group A rotaviruses also all had identical electrophoretypes. In contrast to previous findings in intensive piggeries, rotavirus infection did not occur in all young pigs and was not limited to young animals under 2 m of age. Infected pigs varied in age from 12 days to 20 weeks of age. This pattern of infection was attributed to the non-intensive husbandry situations in the villages, with less opportunity for transmission to occur than in intensive piggeries.  相似文献   
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San Carlos olivine crystals under laboratory conditions of 26 gigapascals and 973 to 1473 kelvin (conditions typical of subducted slabs at a depth of 720 kilometers) for periods of a few minutes to 19 hours transformed to the phase assemblage of perovskite and magnesiowustite in two stages: (i) the oxygen sublattice transformed into a cubic close-packed lattice, forming a metastable spinelloid, and (ii) at higher temperatures or longer run durations, this spinelloid broke down to perovskite and magnesiowustite by redistributing silicon and magnesium while maintaining the general oxygen framework. The breakdown was characterized by a blocking temperature of 1000 kelvin, below which olivine remained metastable, and by rapid kinetics once the reaction was activated.  相似文献   
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Theileria buffeli, generally a benign parasite of cattle, has been reported in animals from Texas, Missouri and North Carolina. To date, there have been no reports of the parasite in cattle residing in northern portions of the US. An 8-year-old cow (Maine Anjou x Angus cross-bred) in Michigan presented with hemoglobinuria and a packed cell volume of 9. Blood films stained with Giemsa showed numerous intraerythrocytic parasites morphologically consistent with T. buffeli. The parasite was confirmed to be T. buffeli by SSU rRNA gene sequence analysis (SSU rRNA sequence, Type A). This represents the first report of this parasite in an animal in Michigan.  相似文献   
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