Pathotyping and antimicrobial susceptibility testing of Escherichia coli isolates from neonatal calves

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.

     

Comparing the model forms estimating generalised diameter-height relationships in Tecomella undulata plantations in hot arid region of India

Four generalised diameter-height equations were developed and compared for pure and even-aged stands of Tecomella undulata in hot arid region of Rajasthan State in India. The data used to fit the equations consisted of 1 540 diameter-height observations collected from the plots laid out in uniformly stocked stands of varying age and density. The performance of four equations was tested by non-linear least squares regression and evaluated using different statistical criteria. Finally, these equations, with the same values of coefficients ob- tained during the fitting phase, were validated by an independent data set consisting of 854 diameter-height observations. Overall, equation （4） （Hui and Gadow function） was found to perform best for both the fitting data set as well as validation data set.     

Developing a dynamic growth model for teak plantations in India

Background： Tectono grandis （teak） is one of the most important tropical timber species occurring naturally in India. Appropriate growth models, based on advanced modeling techniques, are not available but are necessary for the successful management of teak stands in the country. Long-term forest planning requires mathematical models and the principles of Dynamical System Theory provide a solid foundation for these.
Methods： The state-space approach makes it possible to accommodate disturbances and avarying environment. In this paper, an attempt has been made to develop a dynamic growth model based on the limited data, consisting of three annual measurements, collected from 22 teak sample plots in Karnataka, Southern India.
Results： A biologically consistent whole-stand growth model has been presented which uses the state-space approach for modelling rates of change of three state-variables viz., dominant height, stems per hectare and stand basal area. Moreover, the model includes a stand volume equation as an output function to estimate this variable at any point in time. Transition functions were fitted separately and simultaneously. Moreover, a continuous autoregressive error structure is also included in the modelling process. For fitting volume equation, generalized method of moments was used to get efficient parameter estimates under heteroscedastic conditions.
Conclusions： A simple model containing few free parameters performed well and is particularly well suited to situations where available data is scarce.     

Non-suture intestinal anastomosis by invagination

Intestinal anastomoses were performed on seventeen mongrel dogs by non-suture invagination technique and by the conventional method. A comparative evaluation revealed the non-suture technique to be easier and less time-consuming. Also the tissue reaction was minimal. Encouraging results suggest further investigation prior to clinical trial of this relatively new technique. Résumé. Des anastomoses intestinales sur dix-sept chiens métis par l'invagination technique pas de suture et la méthode de convention. Une évaluation comparative a révélé que la technique pas de suture était plus facile et moins de temps était perdu. Aussi la réaction du tissu était minimum. Les résultats encourageants proposent un surcro***ît d'investigation antérieurement a l'expérience clinique de cette technique relativement plus nouvelle. Zusammenfassung. Die Darmanastomosen von siebzehn Mischhunden durch die Intussuscep-tiontecknik keiner Naht und die verabredete Methode. Eine vergleichende Abschatzung zeigte, daß die Tecknik keiner Naht leichter ist, und wenigere Zeitverschwendung hat. Auch war die Reaktion des Gewebes minderst. Die ermutigenden Ergebnisse suggerieren eine Forderung der Erforschung vor klinischem Versuch dieser Tecknik, die verhältnismäßig neuere ist.     

Modulation of manganese toxicity in Pisum sativum L. seedlings by kinetin

In the present study, the effects of kinetin (KN; 10 and 100 μM) application under manganese toxicity (Mn; 50, 100 and 250 μM) were investigated, on growth, photosynthetic pigments, total protein, total nitrogen, ammonium (NH₄⁺) content, NH₄⁺ assimilating enzymes and antioxidant system in pea seedlings. The exposure of pea seedlings to Mn and 100 μM of KN alone and in combination, caused decrease in growth, photosynthetic pigments, total protein and total nitrogen contents, and an increase in NH₄⁺ content. However, application of 10 μM of KN together with Mn reduced the Mn toxicity symptoms, promoted the growth of seedlings and led to the decrease in NH₄⁺ content compared to Mn treatments alone. The root and shoot activities of glutamine synthetase (GS), glutamate oxoglutarate aminotransferase (GOGAT) and catalase (CAT) were decreased while glutathione reductase (GR) and dehydroascorbate reductase (DHAR) activities exhibited differential responses when pea seedlings were exposed to Mn and 100 μM of KN. However, under similar treatments, activities of glutamate dehydrogenase (GDH), superoxide dismutase (SOD) and ascorbate peroxidase (APX) in root and shoot were increased. It was noticed that addition of 10 μM of KN together with Mn, caused significant stimulation in activities of enzymes of NH₄⁺ assimilation and antioxidant defense system even over their respective control values. Non-enzymatic antioxidants (ascorbate and glutathione) in root and shoot of pea seedlings exposed to Mn stress were significantly increased by the addition of 10 μM of KN. Therefore, ameliorative effect of 10 μM of KN against Mn toxicity was observed. This study thus suggests that 10 μM of KN appreciably improves Mn tolerance of pea seedlings under Mn toxicity while reverse effects were exhibited by 100 μM of KN.     

Productivity and Sustainability of Cotton (Gossypium hirsutum L.)–Wheat (Triticum aestivum L.) Cropping System as Influenced by Prilled Urea, Farmyard Manure and Azotobacter

Field experiments were conducted at Indian Agricultural Research Institute, New Delhi, during 2001–2002 and 2002–2003, to study the effect of inorganic, organic and Azotobacter combined sources of N on cotton (Gossypium hirsutum L.) and their residual effect on succeeding wheat (Triticum aestivum L.) crop. The results indicated considerable increase in yield attributes and mean seed cotton yield (2.33 Mg ha^?1) with the combined application of 30 kg N and farmyard manure (FYM) at 12 Mg ha^?1 along with Azotobacter (M₄). The treatment in cotton that included FYM, especially when fertilizer N was also applied could either improve or maintain the soil fertility status in terms of available N, P and K. Distinct increase in yield attributes and grain yield of wheat was observed with the residual effect of integrated application of 30 kg N ha^?1 + FYM at 12 Mg ha^?1 + Azotobacter. Direct application of 120 kg N ha^?1 resulted 67.4 and 17.7 % increase in mean grain yield of wheat over no N and 60 kg N ha^?1, respectively. Integrated application of organic and inorganic fertilizer is therefore, recommended for higher productivity and sustainability of the cotton–wheat system.     

Effects of SO2 exposure on carbohydrate contents,phytomass and caloric values of wheat plants

This paper reports the results of wheat plants exposed to SO₂. The SO₂-treated and control plant samples were periodically analyzed with respect to their carbohydrate content, caloric values, phytomass accumulations and net primary productivity. An initial increase, but later decrease in all these parameters was recorded in SO₂-treated plants. These effects in wheat plants have been interpreted in terms of energy budget of plants under SO₂-stress condition.     

Removal of chrome dye from aqueous solutions by fly ash

The ability of fly ash to remove Omega Chrome Red ME (a chrome dye, mostly used in textile industries) from water has been studied. It has been found that low adsorbate concentration, small particle size of adsorbent, low temperature, and acidic pH of the medium favor the removal of chrome dye from aqueous solutions. The dynamics of adsorbate transport from bulk to the solid phase has been studied at different temperatures in light of the adsorption of dye on the outer surface as well as diffusion within the pores of fly ash. The applicability of Langmuir isotherm suggests the formation of monolayer coverage of dye molecules on the outer interface of adsorbent. The thermodynamics of chrome dye-fly ash system indicates spontaneous and exothermic nature of the process. The pronounced removal of chrome dye in the acidic range may be due to the association of dye anions with the positively charged surface of the adsorbent.     

Influence of rates and sources of nitrogen on growth,nitrogen uptake and yield of cotton (G. hirsutum L.)

Field experiments on cotton with different forms of urea applied at rates of 40 and 80 kg N/ha were carried out. The results indicated that application of nitrogen increased plant height, dry matter accumulation, number of bolls per plant, seed cotton yield and nitrogen uptake. The proportion of dry matter and nitrogen in the stem was increased and that in the leaves was reduced by N application. Sulphur coated urea (all applied at sowing) was about the same in effect as N-Serve treated urea and gave significantly more seed cotton yield than untreated urea, neem cake treated urea and sulphur coated urea (applied in two splits). Nitrogen efficiency as expressed by kg seed cotton production per kg N applied was greater with 40 kg N/ha rate than with 80 kg N/ha. Sulphur coated urea (all applied at sowing) gave the highest nitrogen efficiency followed by N-Serve treated urea.