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61.
Olsen I Johansen TB Billman-Jacobe H Nilsen SF Djønne B 《Veterinary microbiology》2004,98(3-4):297-306
A novel insertion element belonging to the IS110 family was identified in Mycobacterium avium subsp. paratuberculosis. The IS element, ISMpa1, is 1500 bp and has one ORF encoding a putative transposase. Three copies of ISMpa1 were identified in the M. avium subsp. paratuberculosis genome. The element had inserted into the 3' end of the highly conserved mycobacterial genes prrB and a homologue of M. tuberculosis Rv1593c, and between a putative cytochrome p450 oxygenase and a putative hydrolase. The IS element was present in all (n = 11) M. avium subsp. paratuberculosis strains but not detected in most other mycobacterial species examined, including 10 M. avium subsp. avium isolates of human, avian and porcine origin. However two porcine isolates of M. avium subsp. avium and the reference strain IWGMT49 did harbour ISMpa1. These three strains belong to a previously described subgroup of M. avium subsp. avium based on IS1245 restriction fragment length polymorphism (RFLP) pattern and serovars. All of the M. avium subsp. paratuberculosis strains examined had an identical RFLP pattern when probed with sequences corresponding to the 5' end of ISMpa1, whereas a different pattern was seen in the positive M. avium subsp. avium strains. This novel IS element might be a useful tool in strain classification of M. avium subsp. avium and also for the identification of M. avium subsp. paratuberculosis when used in combination with IS900. 相似文献
62.
Positive PCR alone should not be considered sufficient to establish Dirofilaria repens as the cause of subcutaneous nodular lesions in the absence of a clear cytologic picture 下载免费PDF全文
63.
Nitrogen transformation rates and N<Subscript>2</Subscript>O producing pathways in two pasture soils
Ting Lan Helen Suter Rui Liu Xuesong Gao Deli Chen 《Journal of Soils and Sediments》2018,18(9):2970-2979
Purpose
Better understanding of N transformations and the regulation of N2O-related N transformation processes in pasture soil contributes significantly to N fertilizer management and development of targeted mitigation strategies.Materials and methods
15N tracer technique combined with acetylene (C2H2) method was used to measure gross N transformation rates and to distinguish pathways of N2O production in two Australian pasture soils. The soils were collected from Glenormiston (GN) and Terang (TR), Victoria, Australia, and incubated at a soil moisture content of 60% water-filled pore space (WFPS) and at temperature of 20 °C.Results and discussion
Two tested pasture soils were characterized by high mineralization and immobilization turnover. The average gross N nitrification rate (ntot) was 7.28 mg N kg?1 day?1 in TR soil () and 5.79 mg N kg?1 day?1 in GN soil. Heterotrophic nitrification rates (nh), which accounting for 50.8 and 41.9% of ntot, and 23.4 and 30.1% of N2O emissions in GN and TR soils, respectively, played a role similar with autotrophic nitrification in total nitrification and N2O emission. Denitrification rates in two pasture soils were as low as 0.003–0.004 mg N kg?1 day?1 under selected conditions but contributed more than 30% of N2O emissions.Conclusions
Results demonstrated that two tested pasture soils were characterized by fast N transformation rates of mineralization, immobilization, and nitrification. Heterotrophic nitrification could be an important NO3?–N production transformation process in studied pasture soils. Except for autotrophic nitrification, roles of heterotrophic nitrification and denitrification in N2O emission in two pasture soils should be considered when developing mitigation strategies.64.
Assessing general combining ability for gangrene resistance by means of a glasshouse seedling test 总被引:3,自引:0,他引:3
Summary A seedling progeny test for resistance to gangrene (Phoma foveata) was used to evaluate progenies from a 15×15 half diallel set of crosses, including 14 selfs and 25 reciprocal crosses, which
was originally made to investigate the inheritance of resistance to late blight and cyst nematodes. Nine out of the 14 selfs
were more susceptible than the crosses involving their parents, so that overall the selfs were slightly more susceptible than
the crosses, thus providing evidence of non-additive gene action in favour of resistance. However, when the selfs were omitted
from the analysis, all of the variation between progenies could be attributed to differences in the General Combining Abilities
(GCAs) of their parents. The four parents with the best GCAs for gangrene resistance all had sizeable contributions fromSolanum tuberosum subsp.andigena in their pedigrees. 相似文献
65.
Inter-provenance hybrids of Pinuscaribaea var. hondurensis wereprogeny tested in Queensland, Australia inorder to assess the feasibility ofincorporating some desirable traits intothe local breeding population, consistinglargely of a single upland provenanceMountain Pine Ridge (MPR). Data onphenotypic traits up to seven years fromplanting revealed that an inter-provenancehybrid, MPR × coastal had greater diameter,straightness and wind-firmness, and fewerramicorns than the MPR control provenance.The data were mostly consistent for twowidely separated sites, and also whenpooled across those sites (p <0.05). In addition, hybrid vigor for treevolume was apparent (p < 0.05).Trees of coastal × Guanaja Island, and purecoastal provenances were as large as thoseof the MPR provenance but had fewerramicorns. Even though the coastal ×Guanaja provenance seemed to produce treesthat were more crooked than the MPRprovenance, there was evidence at leastwithin one site to suggest that the hybridtrees were superior in terms ofwind-firmness (p < 0.01). Breedingfor hybrid vigor and pedigree selection ofthe priority hybrid, MPR × coastal aresuggested as future measures. Pureprovenance populations of coastal andGuanaja island are to be bred as sublinesto the MPR breeding population for futureuse in inter-provenance hybridization andfor gene conservation. 相似文献
66.
Yield loss due to grazing by mute swans was measured on two fields each of autumn-sown oilseed rape and winter wheat, located in three regions of the UK. Using a paired plot design, a 33.7% reduction in yield (total dry weight of seed) and a 12.1% reduction in the thousand-seed weight was measured in the rape field subjected to the highest grazing intensity. No significant yield loss was measured in the other three fields. Yield loss was related to: (i) the timing of the onset of grazing, and (ii) the duration of grazing (both estimated from counts of mute swan droppings). Management measures which delay the onset of grazing and/or reduce the duration of grazing are therefore likely to reduce yield loss. 相似文献
67.
Distribution,characteristics and condition of Arctic charr (Salvelinus alpinus) spawning grounds in a differentially eutrophicated twin‐basin lake 下载免费PDF全文
68.
This retrospective study of 51 dogs with atopic dermatitis (AD) treated with cyclosporine (CsA) for a minimum of 6 months assessed the frequency of dosing and the need for continual treatment to control clinical signs. The study evaluated both medical records and information supplied by the owners in the form of written questionnaires and telephone follow-up. Laboratory parameters, possible adverse effects and owner satisfaction were assessed. The dose of CsA was 5 mg/kg orally per day and dogs received CsA for 6-30 months. At the conclusion of the study period, 28 dogs (55%) needed ongoing CsA to control clinical signs of AD: 8 (15%) received CsA 2-3 days per week, 10 (20%) 4-5 days per week, and 10 (20%) daily. CsA was discontinued in 23 dogs (45%) after 6-24 months due to either a limited response (22%) or after achieving a clinical response (24%). The results suggest that some dogs with AD treated with CsA may not require daily or even ongoing treatment to control clinical signs. Laboratory abnormalities were detected in 13 dogs (25%) during their CsA treatment. Two dogs developed oral growths and three developed hirsuitism. Forty owners (78%) reported no adverse events in their dogs during the treatment period. Thirty-six owners (71%) were satisfied with CsA as treatment for their atopic dog. 相似文献
69.
Association of genes encoding beta2 toxin and a collagen binding protein in Clostridium perfringens isolates of porcine origin 总被引:1,自引:0,他引:1
Clostridium perfringens is a cause of economically significant enteritis in livestock. Beta2 toxin, encoded by one of two cpb2 alleles, is implicated as a virulence factor in this disease. Previous studies determined that the consensus cpb2 allele is preferentially associated with C. perfringens isolated from pigs. In C. perfringens strain 13, the consensus cpb2 allele is found on the plasmid pCP13, which also carries cna, encoding a putative collagen binding protein, CpCna. This protein was shown to be a bona fide collagen adhesin, as recombinant, HIS-tagged CpCna bound collagen type I as determined by Far Western blotting. Genomic DNA from C. perfringens isolated from a variety of host species were subjected to PCR to determine the prevalence of cna in these strains and correlate its carriage with the presence and type of cpb2 allele. The cna gene was found in 55.8% of isolates from all host species (n=208) and 68.1% of porcine isolates (n=119). In cpb2+ isolates, cna was present in 69.9% of isolates from all hosts (n=153), but was found in 98.7% of porcine isolates (n=75). Furthermore in porcine isolates, the consensus cpb2 allele and cna were absolutely correlated with the presence of pcp12, a pCP13-encoded gene, and pcp12 was never found in any isolate that lacks either cpb2 allele. The finding that CpCna binds collagen and that the cna gene is associated with the consensus cpb2 allele implicates CpCna as a potential virulence factor in porcine enteritis caused by C. perfringens. 相似文献
70.
Compromised lung function is a feature of both infection driven and non-infective pathologies. Viral infections—including the current pandemic strain SARS-CoV-2—that affect lung function can cause both acute and long-term chronic damage. SARS-CoV-2 infection suppresses innate immunity and promotes an inflammatory response. Targeting these aspects of SARS-CoV-2 is important as the pandemic affects greater proportions of the population. In clinical and animal studies, fucoidans have been shown to increase innate immunity and decrease inflammation. In addition, dietary fucoidan has been shown to attenuate pulmonary damage in a model of acute viral infection. Direct inhibition of SARS-CoV-2 in vitro has been described, but is not universal. This short review summarizes the current research on fucoidan with regard to viral lung infections and lung damage. 相似文献