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71.
72.
Brassica napus plants, artificially synthesized through somatic hybridization of B. oleracea and B. campestris protoplasts, were analyzed by oligonucleotide fingerprinting. While the fingerprint patterns of the different hybrid plants looked very much alike, they did not simply represent a combination of the parental patterns. Instead, the absence of parental bands as well as the presence of new bands suggest that elimination and/or rearrangements occurred during or after the fusion of the two genomes. The fingerprints of individual F1 progeny plants of selfed hybrids did not detect major changes. Thus, once formed, the artificially resynthesized amphidiploid B. napus genome appears to be stable. Taken together, our experiments demonstrate the usefulness of oligonucleotide fingerprinting for the characterization of artificial hybrids in the genus Brassica. 相似文献
73.
Genetic transformation of Brassica 总被引:10,自引:0,他引:10
G. B. Poulsen 《Plant Breeding》1996,115(4):209-225
Tissue culture regeneration of plants from Brassica species can be achieved from various explant types. Their performance, however, varies with the genotype and age of the explant and is sensitive to medium supplements and Agrobacterium cocultivation. Most Brassica transformations were carried out using Agrobacterium and it was established that nopaline and agropine strains of A. tumefaciens and A. rhizogenes, respectively, are the most efficient. Application of virulence gene induction is ambiguous. Binary vectors are mostly applied in spite of indications that cointegrate vectors are more efficient. Cotransformation is successful with two different bacteria or with one bacterium carrying both plasmids, however, it has proved problematic to integrate the two transgenes into separate loci. Transformations with wild type rol genes develop hairy roots, from which transgenic plants can be regenerated. Vectorless transformation is feasible with microprojectile bombardment of microspore derived embryos being the most promising. Antibiotic markers providing resistance to kanamycin, hygromycin, and spectinomycin are applicable as selectable markers, while chloramphenicol is not suitable. Among herbicides, phosphinotricin gives good results while chlorsulfuron is unsuitable for in vitro selection. Major therapeutic antibiotics being successfully applied are carbenicillin, cefotaxime, amoxycillin, and ticarcillin. Standard methods for evaluating transgenic plants also have been applied to Brassica species. Some breeding objectives obtained through genetic transformation are presented. 相似文献
74.
The objective was to quantify the retention of digesta and evaluate the degradation of phytate or inositol hexakisphosphate (InsP(6)) and lower inositol phosphates (InsP?, InsP?, InsP?, and InsP?) in the stomach at different times after feeding pigs a fermented liquid diet with microbial phytase or a nonfermented diet with or without microbial phytase. Six barrows fitted with gastric cannulas were used. The experiment was a 3 × 3 Latin square with 3 pigs fed 3 diets during 3 wk in 2 replicates. Each experimental period lasted for 7 d, comprising 3 d of adaptation and 4 d of total collection of gastric digesta. For each pig, the digesta was collected once daily at 1, 2, 3, or 5 h after feeding the morning meal. A basal wheat- and barley-based diet was steam-pelleted at 90°C. The dietary treatments were a nonfermented basal diet (NF-BD), the NF-BD with microbial phytase (750 phytase units of phytase/kg, as-fed basis; NF-BD + phytase), and the NF-BD + phytase fermented for 17.5 h (F-BD + phytase). Gastric InsP?-P was not detected at all in pigs fed F-BD + phytase because of complete InsP? degradation during fermentation of the feed before feeding. Gastric InsP?-P decreased over time (P < 0.05) in pigs fed NF-BD and NF-BD + phytase. The decreases were 45, 54, 56, and 61 percentage points greater at 1, 2, 3, and 5 h, respectively, in pigs fed NF-BD + phytase compared with NF-BD. However, substantial amounts of InsP? still passed into the small intestine in pigs fed NF-BD + phytase, especially within the first hour (estimated to 17% of InsP?-P intake). The accumulation of lower inositol phosphates in gastric digesta was very small for all treatments and at all times because of a rapid and almost complete degradation. In conclusion, phytase addition to the nonfermented diet increased the degradation of gastric InsP?. However, considerable amounts of intact InsP? still passed into the small intestine because of a shortage of time for InsP? degradation in the stomach. Therefore, to increase the apparent digestibility of plant P in dry wheat- and barley-based diets, the development of phytases that can degrade InsP? effectively immediately after ingestion of the feed at an initial gastric pH from 6.5 to 5.0 is needed. Feeding F-BD + phytase compensated for the shortage of time because the InsP? degradation was completed during fermentation before feeding. The degradation of InsP? to InsP? is the bottleneck for plant P utilization in pigs because the degradation of the lower inositol phosphates is rapid and almost complete. 相似文献
75.
Nissen S Poulsen IH Nejsum P Olsen A Roepstorff A Rubaire-Akiiki C Thamsborg SM 《Tropical animal health and production》2011,43(3):567-572
During the last 30 years, pig production in Uganda and neighbouring counties has increased markedly. Pigs are mainly kept
as a source of income for small-scale farmers; however, the pig production is subject to several constraints, one of them
being worm infections. A study was carried out in rural communities in Kabale District in the South Western part of Uganda
in September and October 2007 in order to estimate the prevalence of gastrointestinal nematode parasites in pigs based on
coprological examination. Fifty-six households were randomly selected and visited. Housing system and deworming history were
recorded. Faeces was sampled from rectum of one to five pigs (age, 3–12 months) per household. A total of 106 pigs were examined
coprologically of which 91% excreted nematode eggs. The following prevalences of nematode eggs were recorded: strongyles (89%),
Ascaris suum (40%), Trichuris suis (17%) and spiruroid eggs (48%). On household level, rearing pigs on slatted floors in pens significantly reduced the faecal
egg excretion of strongyle eggs with almost 80% (p = 0.010) and a significant interaction between floor type and anthelmintic treatment was found for spiruroids (p = 0.037). Fifteen T. suis egg positive pigs were selected for post-mortem examination of the gastrointestinal tract. The post-mortem examinations revealed
that 93% pigs were infected with Oesophagostomum spp. (worm burden, min–max 10–2,180), 73% with A. suum (1–36), 67% with T. suis (6–58), and 20% with Hyostrongylus rubidus (worms not quantified). In general, nematode infections were widespread and polyparasitism common in pigs in Uganda. However,
worm burdens were moderate which may be related to recent deworming or to the practice of rearing pigs on slatted floors in
wooden elevated pens. 相似文献
76.
Hardefeldt LY Poulsen KP Darien BJ 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(2):253-255
A 3-month-old Hereford heifer calf was presented for lethargy. Blood gas analysis and plasma biochemical testing revealed severe metabolic acidosis, azotemia, hyponatremia, hyperchloremia, and normal anion gap. Results of a urinalysis were consistent with acute tubular necrosis with inadequate acidification of urine based on the degree of acidemia. Salmonella enterica serovar agona was cultured from both urine and feces. The calf was treated with intravenous polyionic fluids, bicarbonate, and antimicrobials. Acidosis and azotemia resolved, and 4 months following initial presentation the heifer was clinically normal. 相似文献
77.
Stina Christensen Roland von Bothmer Gert Poulsen Lorenzo Maggioni Marianne Phillip Bente Anni Andersen Rikke Bagger Jørgensen 《Genetic Resources and Crop Evolution》2011,58(5):657-666
AFLP markers were used to characterize diversity and asses the genetic structure among 17 accessions of kale landraces, cultivars
and wild populations from Europe. The range of average gene diversity in accessions was 0.11–0.27. Several landraces showed
higher levels of diversity than the wild populations and one cultivar had the lowest diversity measures. The landraces that
were most genetically diverse were from areas where kales are known to be extensively grown, suggesting in situ conservation in these areas as a supplement to storage of seeds in gene banks. An analysis of molecular variance (AMOVA)
showed that 62% of the total variation was found within accessions. For most accessions, genetic distance was not related
to geographic distance. Similarities among accessions were probably not caused by recent gene flow since they were widely
separated geographically; more likely the relationship among them is due to seed dispersal through human interactions. Our
results indicate that a kale population found in a natural habitat in Denmark was probably not truly wild but most likely
an escape from a cultivated Danish kale that had subsequently become naturalized. 相似文献
78.
Cutaneous asthenia in the dog. A report of two cases 总被引:1,自引:0,他引:1
Two cases of cutaneous asthenia in Danish dogs are described. Case 1 was a Weimeraner; case 2 a Golden Retriever. In both instances the dogs had acquired numerous lesions of the skin within the first half year of their lives. The wounds exhibited good healing but led to broad, thin and pliable scars. Both dogs had in several instances received attention to gaping wounds, characterized by little tendency of bleeding. The clinical examination reveiled that the skin was hyperextensible and possessed pendulous folds, particularly behind the elbows. The degree of hyperextensibility was evaluated by means of a skin extensibility index. Furthermore, it was possible to manipulate the digital cushion in an unphysiological manner. One of the dogs were euthanised, and in case 2 the clinical diagnosis was confirmed by histopathological examination. No conclusion could be drawn regarding the mode of inheritance in the two cases, but existing literature strongly suggests the existence of a genetic disposition and thus, elimination of the disease related gene from any breeding program is of great importance. 相似文献
79.
Two-dimensional ultrasound was used in combination with colour-coded and pulsed Doppler sonography to study the blood flow of the testes and prostate gland in a total of 30 male dogs. After detection of the vessels by colour-coded Doppler sonography, the blood flow patterns were determined by pulsed Doppler sonography measuring and describing the systolic and diastolic peak velocity (SPV, DPV), the end-diastolic velocity, the time-averaged maximum velocity (TAMAX), the pulsatility and resistance index, as well as the ratios of the systolic peak velocity and end-diastolic velocity and of the systolic and diastolic peak velocities. The blood flow of the testicular artery was measured within the pampiniform plexus and the marginal location. The prostatic blood supply was measured in the artery of the deferential duct (cranial), the prostatic artery outside (lateral) and within the gland (subcapsular). The physiological testicular flow pattern was monophasic with a high diastolic flow. Testes with neoplastic alterations showed a significant increase of SPV and TAMAX. The epididymal vessels could not be detected. Under physiological conditions the prostatic blood flow pattern was biphasic in the cranial and lateral location and monophasic in the subcapsular location. Benign prostatic hyperplasia was characterized by a significant increase of SPV, DPV and TAMAX. The results of the present investigation demonstrate that the colour-coded and pulsed Doppler sonography give additional valuable information which improves the andrological diagnostics in the dog. 相似文献
80.
OBJECTIVE: To analyse the alcohol consumption behaviour of the German adult population, with a focus on the characteristics of persons drinking more than the tolerable upper alcohol intake level (TUAL) of 10-12 g day(-1) for healthy adult women and 20-24 g day(-1) for healthy adult men. DESIGN AND SETTING: For the German National Health Interview and Examination Survey 1998, a representative sample of free-living adults was drawn. A total of 7124 participants were interviewed comprehensively about their sociodemographic background, lifestyle and eating habits including alcohol consumption. SUBJECTS: A sub-sample of 4030 women and men, 18-79 years old, who were involved in the integrated German Nutrition Survey. RESULTS: About 16% of women and 31% of men had mean alcohol consumption above the TUAL. Among other factors, the inclination to exceed the TUAL was related to middle-age, high socio-economic status, smoking and use of soft drugs. Among both women and men, a high proportion of persons drinking above the TUAL was observed among those consuming low amounts of soft drinks, fruit, poultry, milk products, bread and cake/biscuits. Women preferred to drink wine, whereas men preferred to drink beer. CONCLUSIONS: Many Germans have an alcohol consumption level above the TUAL and thus are supposed to be at increased risk for alcohol-associated diseases. 相似文献