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941.
Insulin has been shown to have an impact on both prenatal and postnatal growth. Specific mechanisms of insulin action on adipose cell function and lipid storage are well defined. Insulin probably acts in concert with other anabolic factors (i.e., growth hormone and somatomedins) to stimulate muscle protein anabolism and suppress protein catabolism (Figure 2). Insulin also plays a role in energy balance regulation by the hypothalamus, however exact mechanisms of effects on brain metabolism have not been clearly identified. 相似文献
942.
Detailed post mortem examinations were carried out on 41 harbour porpoises (Phocoena phocoena) found dead on the coast of the United Kingdom. The commonest causes of death were entanglement in fishing gear, and parasitic and bacterial pneumonia. Among the non-fatal conditions parasitoses of various organs were common and there was a very wide variety of other conditions. In total 295 diseases and other lesions were found, an average of 7.2 per animal. 相似文献
943.
Treatment of cryptococcosis in three cats, using ketoconazole 总被引:1,自引:0,他引:1
V W Pentlarge R A Martin 《Journal of the American Veterinary Medical Association》1986,188(5):536-538
Ketoconazole was effective in the treatment of cryptococcosis in 3 cats. A dosage of 10 to 15 mg/kg of body weight was given once or twice daily with a meal for 11 to 33 weeks. Fungal cultures and serotesting were used to assess the efficacy of treatment and resolution of active infection. In some of the cats, the treatment was associated with gastrointestinal signs and increased serum liver enzyme activity. Ketoconazole has been used in human beings, dogs, and cats for the treatment of systemic mycoses. 相似文献
944.
Body composition, liver and adipose lipogenesis, and pancreatic insulin release were examined in intact and decapitated fetal pigs on d 110 of gestation. Decapitation was on d 45 of gestation. Decapitated fetuses deposited more body lipid and less body ash compared with intact fetuses. Body weight, water, dry matter and protein remained similar in intact and decapitated fetuses. Hepatic fatty acid esterification and synthesis were two- and threefold greater, respectively, in decapitated than in intact fetuses. Fatty acid synthesis in subcutaneous adipose tissue of decapitated fetuses was three times greater than values obtained in intact fetuses. The data supported the concept that substrate availability from the dam was not the rate-limiting step in fetal pig lipid synthesis and storage. High growth hormone levels in normal fetal pigs may be responsible for inhibiting lipogenesis, while fetal decapitation would remove this inhibition and be associated with greater lipid deposition. However, pancreatic insulin release was greater in decapitated than in intact fetuses; an indication that elevated lipid deposition may also be due to greater fetal insulin secretion. 相似文献
945.
The development of the peritoneal folds of the testis, epididymis and ductus deferens of the pig prior to testicular descent was studied in 18 to 82 days-old embryos/fetuses. The parietal attachment of the mesonephros, mesonephric and paramesonephric ducts and gubernaculum constituted the urogenital mesentery. This could be divided in a cranial and a caudal part. The first fixed the mesonephros and had a mesogonad as a secondary fold. The second had two branches, one laterally to the umbilical artery belonging to the gubernaculum (Plica gubemacularis) and the medial to the artery contained the meso- and paramesonephric ducts. The mesogonad was related caudally with Plica gubemacularis. The fold of the meso- and paramesonephric ducts could also be divided in two parts. The caudal was a primary component of the urogenital mesentery, while the cranial was first ventral and later lateral to the mesogonad (mesorchium) and appeared as a secondary fold of the urogenital mesentery (cranial part). A vascular fold contributed to separate the suspensory ligament of the testis from the developing mesorchium. The proposed meaning of the terms used might be useful for comparative studies. 相似文献
946.
Martin Upton 《Agricultural Systems》1985,17(2):65-83
Dwarf goats and sheep are ubiquitous in the humid zone of West Africa, although only as a supplement to cash and food crop production. This paper presents estimates of the returns obtained from these small ruminants under traditional production systems. Returns are, on average, high, but variable, especially in view of disease risks. Apart from disease control measures to reduce mortality, improved nutrition is needed for intensifying production. At current levels of management neither pasture production nor housing and hand-feeding are likely to yield increased returns. Alley farming, a system of intercropping with shrub species and the feeding of shrub trimmings to small ruminants, seems a promising alternative. 相似文献
947.
948.
Martin Adámek Zuzana Jankovská Věroslava Hadincová Emanuel Kula Jan Wild 《Landscape Ecology》2018,33(11):2031-2045
Context
Wildfires in temperate Central Europe have traditionally been perceived as a mere consequence of human activity without any relevance to natural forest development, despite their documented frequent occurrence. As a result, knowledge about local fire ecology and patterns of wildfire occurrence in the landscape is lacking.Objectives
We aimed to reveal the factors influencing the spatial distribution of forest fires in the Czech Republic as a model area for the broader region. Specifically, we aimed to (1) find out which factors influence the occurrence and frequency of the forest fires at the country scale and in a selected fire-prone region; (2) examine the relationship of lightning strikes and their polarity with wildfire incidence; (3) identify the conditions determining areas with naturally driven fire-prone conditions.Methods
We took data on 15,985 wildfire records and explored their spatial distribution using GIS layers of human, topographic, climatic and vegetation composition factors. We analysed the data using GLM and hierarchical partitioning methods.Results
Wildfire occurrence was controlled mostly by environmental factors whereas wildfire frequency was strongly driven by human factors. In the selected fire-prone region, the effect of environmental factors was even more pronounced and wildfire frequency was also driven, albeit marginally, by lightning strikes of positive polarity.Conclusion
The pattern of wildfire occurrence in the Czech Republic was similar also to those from regions where wildfire is considered a natural part of local ecosystems. We identified the areas with natural fire-prone conditions which probably led to the development of local fire-adapted ecosystems.949.
Ndahetuye Jean Baptiste Persson Ylva Nyman Ann-Kristin Tukei Michael Ongol Martin Patrick Båge Renée 《Tropical animal health and production》2019,51(7):2037-2044
Tropical Animal Health and Production - The aim of this cross-sectional study was to evaluate the prevalence of subclinical mastitis (SCM) and associated risk factors in dairy cows in peri-urban... 相似文献
950.
A number of commercially available disinfectants are commonly used on pig breeding farms and are authorised by the French Agricultural Ministry. However, the efficacy of these disinfectants is unknown with regard to the emergent porcine circovirus type 2 (PCV2). The virucidal efficacy of nine disinfectants was evaluated by testing a suspension of PCV2 isolated in France. The assays were performed at 20 degrees C and the efficacy determined after 30 min contact time between virus and disinfectant. After this time, the mixture was passed through a detoxification column and then diluted to remove compounds toxic to the virus and the porcine kidney cell line. The filtrate was serially diluted and inoculated onto cell culture. The infectivity of PCV2 was determined by an immunoperoxidase monolayer assay. No reduction in PCV2 titre was demonstrated with iodine and phenolic products. Significant PCV2 titre reductions (1.61 log(10)) were noted for the seven other products. For five disinfectants, namely a product composed of potassium monopersulfate, two products comprising a quaternary ammonium with one or three aldehyde(s), sodium hypochlorite, and sodium hydroxide, the concentration that significantly reduced the PCV2 titre was equal or 1.5-4 times lower than the authorised use concentration. Only two disinfectants, one composed of potassium monopersulfate, the other containing peracetic acid with hydrogen peroxide, reduced the PCV2 titre with a product concentration at best equal or two times higher than the authorised use concentration. 相似文献