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作者就大蚕省力化养蚕技术进行了试点分析,分析了大蚕每日二回育,三回育的各项经济技术指标,提出了技术处理要点。 相似文献
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Svein Fredrik Mohn 《Acta veterinaria Scandinavica》1982,23(4):503
Two groups of blue fox pups about 1½— 2 and 2½—3 months old, respectively, suffering from experimental encephalitozoonosis, were examined clinically and serologically. Antibodies to Encephalitozoon cuniouli were detected in all pups, the titres varying within the range 10–12,800. In addition to unspecific signs of disease the pups showed various neurological disturbances including ataxia, posterior weakness, lameness and circling behaviour, terminaiting in recumbency, paralysis or convulsions. Reduced sight or blindness was observed occasionally. Some of the pups appeared thirsty. Haematological examinations revealed pronounced leukocytosis without any conspicuous shift within the various groups of leukocytes. Biochemical examinations of serum showed significant elevated values of urea nitrogen, creatinine, and magnesium concentrations, reflecting renal dysfunction. Alanine aminotransferase was found significantly depressed in both groups. Raised levels of total protein were demonstrated due to pronounced hyperglobulinaemia. This finding, together with the common occurrence of generalized polyarteritis nodosa and proliferations of plasma cells in clinically affected pups, is probably a result of autoimmune disturbances initiated directly or indirectly by the protozoan infection. 相似文献
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Study on the association of BoLA-DRB3.2 alleles with clinical mastitis in Norwegian Red cows 总被引:2,自引:0,他引:2
S. Kulberg B. Heringstad O.A. Guttersrud & I. Olsaker 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(4):201-207
Genotyping of bovine leucocyte antigen DRB3.2 (BoLA-DRB3.2) in a total of 523 Norwegian Red (NR) cows from two groups selected for high protein yield and low clinical mastitis, respectively, identified 27 previously reported BoLA-DRB3.2 alleles across the groups. Significant differences in BoLA-DRB3.2 allele frequencies were found between the selection groups. Alleles *13, *18, *22 and *27 had a significantly higher frequency in cows selected for low clinical mastitis, while alleles *3, *9, *11 and *26 had a higher frequency in cows selected for high protein yield. Associations between BoLA-DRB3.2 alleles and clinical mastitis were analysed based on mastitis data from 741,072 first-lactation NR cows, of which 452 were genotyped. Alleles *22 and *26 were found to be associated with increased clinical mastitis, while alleles *7, *11, *18 and *24 had a favourable effect on mastitis resistance. Contradictory results from different studies investigating associations between BoLA-DRB3.2 alleles and mastitis indicate that future studies should focus on associations of mastitis with BoLA haplotypes rather than with single BoLA genes. 相似文献
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Exergy, the thermodynamic function that represents the distance of an open system from equilibrium, is proposed as an ecological indicator for summarizing the complex dynamics occurring in a disturbed community during its recovery processes. These complex dynamics can be difficult to capture by using classical indices. In this study, we sampled macrobenthos using the BACI scheme (before versus after; control versus impact) in tidal wetlands of west Chongming Island, China, an area that has been disturbed by ecological engineering measures. Exergy storage is estimated for benthic communities. The control area is proposed as dynamic reference for estimating local exergy storage of the benthic community. Three different methods were used for estimating exergy on the basis of coefficients: (a) taken for taxa groups; (b) estimated from coding genes given for broad taxonomic groups; and (c) estimated from genome size taken as close as possible to the taxonomic level of the species, providing a basis for inferring similarities. We found a decrease of local exergy content in the disturbed area 9 days after the disturbance. Subsequently, the reference exergy of the benthic community increased (i.e. in the surrounding control area) in accordance with the proposed hypothesis regarding the dynamics of exergy storage during a system's development. Estimates of local exergy arrived at using the three methods provided comparable results. Based on this, we then discuss the feasibility of using the more readily available genome size data for estimating exergy. This result may have important implications for broader application of this indicator to biological systems. Moreover, the adjacent control samples seem to represent an appropriate dynamic reference for estimating the local exergy of disturbed communities. We found that exergy was a useful indicator that integrates the processes underlying the recovery of the benthic community after disturbance. 相似文献
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