Neonatal calf mortality is a major concern to livestock sector worldwide. Neonatal calf diarrhoea (NCD), an acute severe condition causes morbidity and mortality in calves. Amongst various pathogens involved in NCD, E. coli is considered as one of the major causes. The study was targeted to characterize E. coli isolates from neonatal calves for diarrhoeagenic Escherichia coli (DEC) types (pathotyping), antimicrobial resistance (AMR) profiling and to correlate with epidemiological parameters. From neonates, a total of 113 faecal samples were collected, out of that 308, lactose fermenting colonies were confirmed as E. coli. Pathotypable isolates (12.3%) were represented by STEC (6.1%), EPEC (2.9%), ETEC (1.9%), EAEC (0.9%) and EHEC (0.3%). Occurrence of STEC was more in non-diarrhoeic calves, whereas ETEC was observed more in diarrhoeic calves. EPEC occurrence was observed in both diarrhoeic and non-diarrhoeic calves. Fishers extract test showed no significant association for occurrence of DEC types to type of dairies, health status, species, breed, age and sex of neonatal calves. Two hundred and eighty isolates were tested for antimicrobial susceptibility. The isolates showed maximum resistance towards ampicillin (55.4%) followed by tetracycline (54.3%), while minimum resistance was observed towards meropenem (2.5%). Multidrug resistant E. coli isolates were found to be 139 (49.6%), and Extended-spectrum beta-lactamase (ESBL) producers were 120 (42.9%). DEC pathotypes like STEC, ETEC, EHEC and EAEC that are also multidrug resistant present in neonatal calves have zoonotic potential and hence are of public health significance.
Summary Colchicine induced tetraploid jute plants were shorter than their diploid counterparts. C2 tetraploid plants became taller than C1 plants. Leaves were larger in size and with higher breadth/length ratios compared to those of diploids. Stomata were bigger than those in diploid leaves but their frequency was less in tetraploid leaves. Tetraploid flowers were bigger than the diploids and bore a reduced number of stamens. Tetraploid pollen grains were larger but the percentage of sterility in them was more than that of the diploids. Fewer fruits with a reduced number of seeds were formed in tetraploid plants. They usually were shorter but wider than diploid fruits. Tetraploid seeds were larger and heavier. C2 tetraploid plants bore more fruits with an increased number of seeds than C1 plants. Breadth of individual fibres increased but length remained unchanged.The paper was read at the Eighth Pakistan Science Conference held at Dacca, 1956. 相似文献
The phase mineralogy and leaching characteristics of some Indian coal fly ashes were studied to assess their safe disposal in abandoned coal mines. Since, fly ash contains a number of toxic trace elements, the leaching of fly ash was tested using strong acid/alkali solutions and distilled water under different conditions (solid-liquid ratio, leaching time, pH) in the temperature range of 30-100 °C. It was found that the concentration of various metals in leachates depends on their chemical nature, association with mineral phases of ash and follows the almost similar concentration profile to that of iron, especially in acidic medium. The distribution of toxic trace elements in fly ash and their leachability were found to depend on the amount of unburnt carbon and iron in fly ash. In alkaline medium, leaching of iron and toxic trace elements (except As) from fly ash was very negligible. Hence, alkali treatment of coal fly ash is desirable for its safe use in refilling of coal mines. 相似文献
Brucella abortus, a gram negative, facultative intracellular pathogen causes brucellosis in many animal species and humans. Although live,
attenuated vaccines are available against this infection, they suffer from certain limitations. Therefore, the development
of an effective subunit vaccine against brucellosis is an area of intense research. The outer membrane proteins (OMPs) of
Brucella species have been extensively studied for its immunogenicity and protective ability. We have investigated the potential of
CpG ODN to enhance the immunogenicity and protective efficacy of recombinant 28 kDa outer membrane protein (rOMP28) of Brucella melitensis. The study demonstrated vigorous immunoglobulin G (IgG) response of OMP28. The administration of rOMP28 with CpG caused increased
cell mediated immune response in terms of induced IgG2a, T-cell proliferation and up-regulation of type I cytokine expression.
In contrast, the free antigen suppressed the interferon gamma (type I cytokine) production on in-vitro stimulation of spleenocytes.
The result indicates the role of OMP28 in the down regulation of IFN-γ production. Moreover, the B. abortus S-19 vaccinated mice showed highest production of IL-4 and IFN-γ. The protective ability of the antigen was evaluated by
systemic bacterial clearance after challenging the mouse with B. abortus 544 pathogen. The level of protection was significant in rOMP28+CpG treated mice but was lower than the required level. The
results of the present study indicate that rOMP28 could be an immunogen capable of inducing both humoral and cellular immune
response. The humoral response was biased towards Th1 type when it was co-administered with CpG. 相似文献
Repetitive extragenic palindromic sequence-based PCR (REP-PCR) was used to characterize 67 field isolates of Pasteurella multocida originating from different animal species and geographical regions of India. REP-PCR was found to be rapid and reproducible
(three repeats were done). These isolates yielded different 23 profiles which were clustered into eight groups. The discrimination
index was moderate (D value 0.83). Somatic and antigenic typing of the isolates did not reveal any correlation with REP-PCR profiles. There was
no host-specific, type-specific, region-specific or pathenogenicity-specific pattern. The REP profiles of isolates obtained
from wild animals were similar to those obtained from domestic animals. Two common bands were present in all the isolates
irrespective of somatic or antigenic types. The results were not comparable with earlier findings, which had shown high discrimination
index and correlation with disease presentation.
Saxena, M.K., Singh, V.P., Kumar, A.A., Chaudhuri, P., Singh, V.P., Shivachandra, S.B., Biswas, A. and Sharma, B., 2006. REP–PCR
analysis of Pasteurella multocida isolates from wild and domestic animals in India. Veterinary Research Communications, 30(8), 851–861 相似文献
Repetitive extragenic palindromic (REP)-PCR (polymerase chain reaction), enterobacterial repetitive intergenic consensus (ERIC)-PCR, and single primer PCR assays were employed to characterize 66 strains of Pasteurella multocida serogroup A:1 isolated from avian species belonging to different regions of India. REP-PCR resulted in amplification of REP sequences from the genome which were in the range of approximately 200 to approximately 3000 bp and accounted for a total of 54 distinguishing profiles (D=0.99). ERIC-PCR analysis also generated amplified products in the range of approximately 200 to approximately 3200 bp categorizing strains into a total of 50 different profiles (D=0.98). Amplification of repetitive regions using a microsatellite primer (GTG)(5), resulted in clear distinctive bands ranging from approximately 200 to approximately 2400 bp. Strains were assigned to 43 profiles (D=0.96). No correlation could be drawn between genotypic profiles and avian hosts with their geographical area of origin. Avian strains of P. multocida serogroup A:1 were found to be highly heterogeneous with diverse profiles. REP-PCR was found to be highly discriminatory and simple method for differentiation of phenotypically similar strains. The present study also indicated that PCR based amplification of repetitive regions of P. multocida is a rapid technique with good discrimination and could be employed directly for routine typing of field isolates from fowl cholera outbreaks. 相似文献