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101.
Intestinal contents of newborn and young germ-free minipigs and germ-free rats were investigated for the following biochemical parameters - conversion of cholesterol to coprostanol, degradation of beta-aspartylglycine, level of tryptic activity, formation of urobilinogen and the profile of short-chain fatty acids. Additionally, germ-free minipigs and germ-free rats were monoassociated with non-pathogenic strains of Escherichia coli and were investigated for the same biochemical parameters. The conversion of cholesterol to coprostanol, degradation of beta-aspartylglycine, tryptic activity and the short-chain fatty acid profile were similar to those found in previous studies in germ-free animals. Slightly higher amounts of urobilinogen than in the other species investigated so far were found in samples from germ-free and monoassociated minipigs. Except for the total amount of short-chain fatty acids in rats, monoassociation with E. coli did not alter any of the parameters either in the minipigs or in the rats.  相似文献   
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This report chronicles recurring outbreaks of Haemoproteus lophortyx infection in captive bobwhite quail. Clinically, the signs of infection included reluctance to move, ruffled appearance, prostration, and death. These signs were associated with parasitemia, anemia, and the presence of large megaloschizonts in skeletal muscles, particularly those of the thighs and back. The average cumulative mortality for flocks experiencing outbreaks was over 20%. In a typical outbreak, mortality rose when the birds were 5-6 wk of age, peaked in 8-to-10-wk-old quail, and declined rapidly when the quail were 9-11 wk old. Outbreaks occurred exclusively between the months of May and October, and warm weather was determined to be a risk factor for H. lophortyx mortality. This protozoan most likely overwinters in native California quail in the area and is transmitted to quail on the ranch by an insect vector that emerges in warm weather. Infection of the large population of na?ve bobwhite quail on the ranch leads to amplification of H. lophortyx, resulting in epidemics in successive flocks.  相似文献   
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Arcelin, a major seed protein discovered in wild beans (Phaseolus vulgaris), has toxic effects on an important bean bruchid pest, Zabrotes subfasciatus. Transfer of the arcelin-1 allele to bean cultivars and addition of purified arcelin to artificial seeds results in high levels of insect resistance. The nucleotide and derived amino acid sequences of the arcelin-1 complementary DNA are very similar to those of genes encoding the bean seed lectin, phytohemagglutinin. The gene or genes encoding arcelin may have evolved from a phytohemagglutinin gene or genes resulting in an effective mechanism for resistance to bean bruchids.  相似文献   
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A 1‐year‐old, previously spayed phenotypic female Poodle/Soft‐coated Wheaten Terrier (Whoodle) cross was presented for a suspected ovarian remnant. Serum luteinizing hormone (LH) concentration was below the detection limit (<1 ng/ml Witness® LH), and serum progesterone concentration was elevated in the chemiluminescence immunoassay (CLIA; 20 ng/ml), consistent with dioestrus and presence of ovarian tissue. Transabdominal ultrasound revealed a retroperitoneal soft tissue structure suspected to be a gonad. On exploratory laparotomy, a gonad was removed from the cranial retroperitoneum, cranial to the right kidney, after ligation of its primary blood supply. Histological examination proved the gonad to be an ovotestis. Subsequent cytogenetics revealed a 78 XX karyotype, thus confirming the diagnosis of ectopic ovotestis in a XX ovotesticular, SRY‐negative, disorder of sexual development in a dog.  相似文献   
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Germ‐line chimaerism is a powerful technique that has proved to be useful to produce viable gametes when transplanted blastomeres colonize the germinal ridges in recipient embryos and obtaining offspring from such transplanted cells. In fish, ionizing radiations were commonly used for embryo penalization to cancelling the cell participation of recipient embryos in development and in gamete production. The ultraviolet (UV) radiation when compared with other radiation types is cheaper, easier and no special installations are required for its use. So, the aim of this work was to establish the optimal UV radiation dose to be applied in zebrafish embryos at mid‐blastula transition stage of development, in order to use them as penalized recipient embryos in futures chimaerism assays. A UV germicide lamp was used as radiation source (0.529 mW/cm2). Four exposure levels and three exposure times of UV radiation were tested. The survival rates obtained with the non‐dechorionated embryos without lid group suggested that it could be the optimal exposure level to achieve the objective proposed. With the obtained results, we concluded that this UV radiation dose for 60 and 30 s are optimal parameters to penalize recipient wild and gold strain zebrafish embryos, respectively in chimaerism assays, but without involving their survival and apparently normal development.  相似文献   
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