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排序方式: 共有379条查询结果,搜索用时 15 毫秒
71.
Leonard Ogierman 《Pest management science》1983,14(4):417-422
Phenmedipham and desmedipham, when injected into a gas chromatograph with N, N, N-trimethylanilinium hydroxide, reacted to give derivatives having good gas chromatographic properties. By this procedure, these two carbamate herbicides yielded N-methylated 3-methoxyphenylcarbamates. Maximum methylation was obtained when the molar ratio of methylating reagent to herbicide was approximately 16: 1. This technique for preparing derivatives provided rapid qualitative and quantitative chromatography of the substances examined, without side-chain decomposition. The derivatives obtained were identified by means of ultraviolet, infrared and mass spectrometric procedures. 相似文献
72.
Acute hepatic necrosis and death in a subadult southern white rhinoceros (Ceratotherium simum) associated with exposure to sterigmatocystin in forage contaminated with Aspergillus nidulans
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A young male southern white rhinoceros (Ceratotherium simum), which was resident in a zoo as part of a multi‐rhinoceros group, died suddenly. Necropsy and histopathological findings supported a diagnosis of death from acute hepatic necrosis. The microscopic distribution of liver lesions was suggestive of hepatotoxicosis. Further investigation revealed potential exposure to a mycotoxin, sterigmatocystin, present in spoiled lucerne hay contaminated with Aspergillus nidulans. It was concluded that mycotoxicosis was the likely cause of the hepatic necrosis and death in this animal. 相似文献
73.
The objectives of this paper are to review published data on the prevalence and epidemiology of meticillin-resistant Staphylococcus aureus (MRSA) infection and colonization in animals and to provide suggestions for preventing and controlling the problem in veterinary practice. MRSA first emerged as a serious pathogen in human medicine during the late 1970s and has been increasingly reported in animals during the past 10 years. The prevalence of MRSA in human infections varies markedly between geographical areas, being as high as 60% in parts of the USA, 40% in southern Europe but <1% in northern Europe. Epidemiological evidence, including phenotypic and molecular typing data, suggests that MRSA isolates from dogs and cats are indistinguishable from human healthcare isolates, whereas strains of MRSA isolated from horses and associated personnel are different. There is evidence that transfer of MRSA strains can occur between animals and humans and vice versa. Guidelines for the control of MRSA in animals have been drawn up by individual institutions based on those available for human MRSA infection. Risk factors for MRSA infection in animals are currently under investigation and such data are essential for the preparation of specific guidelines for control of MRSA in veterinary practice. 相似文献
74.
Jacek Wawrzykowski Anna Rapacz‐Leonard Dariusz Wicek Marta Kankofer Tomasz Janowski 《Reproduction in domestic animals》2019,54(12):1543-1551
Protein profile of the placenta expresses its function and maintenance. Any alterations can be reflected in qualitative and quantitative changes in this profile. The aim of the present study was the evaluation of protein profile in the placenta of mares suffering from the retention of foetal membranes (FMR) by two separation methods and the comparison with physiologically released tissues. Placentas from 14 healthy, heavy draft mares were collected immediately after the expulsion of newborn. Tissues after homogenization and staining with fluorescent dyes were subjected to electrophoretic as well as chromatographic separation. Electrophoretic gels were statistically analysed for the presence and abundance of examined proteins, while some proteins were identified in chromatographic fractions. Out of 248 spots detected in endometrium, 38 differed significantly between FMR and control animals, while in allantochorion, respective values reached 241 and 27 spots (p < .05). Among identified proteins that expressed higher abundance in endometrium of FMR mares than control animals were prostaglandin reductase, dehydrogenase/reductase SDR family, and placental growth factor. These proteins are involved in regulation of parturition. Additionally, the following proteins responsible for physiological activity of a cell—guanine methyl transferase, aspartyl/asparaginyl beta‐hydroxylase and GTP‐binding protein, were identified. These proteins expressed higher abundance in allantochorion of FMR mares than in controls. This preliminary study confirmed the disturbances in protein pattern between foetal membranes in FMR and healthy mares. Further qualitative and quantitative experiments are necessary to deepen our knowledge on the mechanisms of the retention of foetal membranes in mares. 相似文献
75.
Human case of bubonic plague resulting from the bite of a wild Gunnison's prairie dog during translocation from a plague‐endemic area 下载免费PDF全文
S. D. Melman P. E. Ettestad E. S. VinHatton J. M. Ragsdale N. Takacs L. M. Onischuk P. M. Leonard S. S. Master V. S. Lucero L. C. Kingry J. M. Petersen 《Zoonoses and public health》2018,65(1):e254-e258
Plague is a zoonotic disease (transmitted mainly by fleas and maintained in nature by rodents) that causes severe acute illness in humans. We present a human plague case who became infected by the bite of a wild Gunnison's prairie dog, and a good practical example of the One Health approach that resulted in a rapid public health response. The exposure occurred while the animal was being transported for relocation to a wildlife refuge after being trapped in a plague enzootic area. This is the first report of a human plague case resulting from the bite of a Gunnison's prairie dog. Additionally, we present an observation of a longer incubation period for plague in captive prairie dogs, leading to a recommendation for a longer quarantine period for prairie dogs during translocation efforts. 相似文献
76.
We used factor and path analyses to identify the causal paths or relationships between variables affecting the demand and use by subsistence farmers of the various services offered by government-employed veterinary livestock technicians (VLTs) in Zimbabwe in 1996. We examined whether the farmer had implemented the VLT-recommended livestock-management procedures. Various factors that have been reported or theorised as important in the demand for veterinary services by subsistence farmers are described. The important factors positively affecting whether farmers had sought veterinary assistance in the last 24 months included familiarity of the farmer with the VLT, if situated closer to the VLT’s base, and if the farmer received further training in agriculture (either through courses or from attendance at demonstrations on animal husbandry conducted by the VLT). Factors affecting whether farmers implemented the recommended management practices that had a monetary cost included familiarity with the VLT, proximity to the VLT’s premises, farmer literacy, club membership, and farmer’s wealth. There was a difference in the paths generated for preventive measures that had a monetary cost versus those measures that involved only a labour or effort costs. For the former practices, the VLT played an important role informing farmers by extension and demonstrations, and farmer’s membership of a club increased their performance. 相似文献
77.
JDA Losano DSR Angrimani A Dalmazzo BR Rui MM Brito CM Mendes GKV Kawai CI Vannucchi MEOA Assumpção VH Barnabe M Nichi 《Reproduction in domestic animals》2017,52(2):289-297
Studies have demonstrated the importance of mitochondria to sperm functionality, as the main source of ATP for cellular homoeostasis and motility. However, the role of mitochondria on sperm metabolism is still controversial. Studies indicate that, for some species, glycolysis may be the main mechanism for sperm energy production. For ram sperm, such pathway is not clear. Thus, we evaluated ram sperm in response to mitochondrial uncoupling and glycolysis inhibition aiming to assess the importance of each pathway for sperm functionality. Statistical analysis was performed by the SAS System for Windows, using the General Linear Model Procedure. Data were tested for residue normality and variance homogeneity. A p < .05 was considered significant. Groups treated with the mitochondrial uncoupler Carbonyl cyanide 3 chlorophenylhydrazone (CCCP) showed a decrease in the percentage of cells with low mitochondrial activity and high mitochondrial membrane potential. We also observed that the highest CCCP concentration promotes a decrease in sperm susceptibility to lipid peroxidation. Regardless the lack of effect of CCCP on total motility, this substance induced significant alterations on sperm kinetics. Besides the interference of CCCP on spermatic movement patterns, it was also possible to observe such an effect in samples treated with the inhibitor of glycolysis (2‐deoxy‐d ‐glucose, DOG). Furthermore, treatment with DOG also led to a dose‐dependent increase in sperm susceptibility to lipid peroxidation. Based on our results, we suggest that the glycolysis appears to be as important as oxidative phosphorylation for ovine sperm kinetics as this mechanism is capable of maintaining full motility when most of the cells have a low mitochondrial membrane potential. Furthermore, we found that changes in the glycolytic pathway trough glycolysis inhibition are likely involved in mitochondrial dysfunction and sperm oxidative unbalance. 相似文献
78.
B Behr D Rath TB Hildebrandt F Goeritz S Blottner TJ Portas BR Bryant B Sieg A Knieriem SP de Graaf WMC Maxwell R Hermes 《Reproduction in domestic animals》2009,44(2):273-277
Flow cytometric sexing of spermatozoa followed by application in artificial insemination or in vitro fertilization provides a unique opportunity to predetermine the sex of offspring and might enhance the conservation management of endangered species in captivity such as the elephant and rhinoceros. To obtain an indication of the sortability of spermatozoa from these species, the relative DNA differences between X and Y chromosome bearing spermatozoa (fresh, frozen thawed, epididymal) from three rhinoceros species [white ( Ceratotherium simum ), black ( Diceros bicornis ), Indian ( Rhinoceros unicornis )] and both elephant species, the Asian and the African elephant ( Elephas maximus, Loxodonta Africana ), were determined through separation of spermatozoa into X and Y chromosome bearing populations, using a modified high speed flow cytometer. The head profile areas of spermatozoa from all five species were measured using light microscopy. By multiplying the relative DNA differences and the head profile areas, the sperm sorting indices were calculated to be 47, 48 and 51 for white, black and Indian rhinoceros respectively. The calculated sorting index for the Asian elephant was 66. In the African elephant, we determined the highest sorting index of 76. These results indicate the practicability of flow cytometric sex sorting of spermatozoa from the tested rhinoceros species and both elephant species. The lower sorting indices in rhinos indicate that sex sorting of spermatozoa from the rhinoceros will be more challenging than in elephants. 相似文献
79.
Mathilde Dupont-Nivet Franoise Mdale Julien Leonard Sandrine Le Guillou Franck Tiquet Edwige Quillet Inge Geurden 《Aquaculture (Amsterdam, Netherlands)》2009,295(1-2):15-21
This study examined the genetic variability and genotype × diet interactions during early growth (initial mean body weight 1.2 g) among seven heterozygous clones of rainbow trout, Oncorhynchus mykiss. The clones were hand-fed a diet containing either fishmeal or plant proteins during a 49-day trial divided into two periods (P1, 26 days, and P2, 23 days). Weight, variation of weight within clone, feed intake, feed efficiency and mortality were calculated for both periods.There was a highly significant effect of diet and of clone for all traits at both periods, except for feed efficiency and mortality at P1. Highly significant interactions between diet and clone were also recorded for all these traits, except for mortality at P1. The occurrence of genotype × diet interactions when feeding juvenile rainbow trout with an all plant-protein diet indicates that a highly performing genotype on a fishmeal diet may perform poorly when fed a plant-protein diet. Interactions were found for the two major determinants of growth, i.e. feed intake and feed efficiency, showing that the dietary response differs according to the genotype. Monitoring of the within-clone variability of weight showed that a plant-based diet is likely to enhance the overall phenotypic variance in a population, whatever its initial genetic variability. 相似文献
80.
Brian K. Hamilton Leonard M. Pike Alton N. Sparks David A. Bender Richard W. Jones Jonas Candeia Geraldo de Franca 《Euphytica》1999,109(2):117-122
A two season study was conducted to compare the onion cultivars TG1015Y and IPA-3 for resistance to thrips in South Texas.
Narrow and broad sense heritabilities were estimated from populations developed from the cross, ‘IPA-3’ × ‘TG1015Y’. Parents,
F1, F2, and the respective backcross populations were evaluated for thrips numbers at the Texas Agricultural Experiment Station,
Weslaco, TX. ‘IPA-3’ had significantly fewer thrips than ‘TG1015Y’ in both seasons. Yield was significantly different only
in the 1996–97 season. The heritability of thrips resistance in this study was very low. Depending on the methods of estimation
h
2 was 5.3% and 4.0%, and H
2 was 4.1% and 8.0%. These results suggest that greater genetic gains for thrips resistance in onion can be achieved by selection
on a family basis rather than using single plant selection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献