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1.
Nitrous oxide emission from a transplanted rice field in alluvial soil as influenced by management of nitrogen fertiliser 
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下载免费PDF全文 We investigated nitrous oxide (N2O) emission from an irrigated rice field over two years to evaluate the management of nitrogenous fertiliser and its effect on reducing emissions. Four forms of nitrogenous fertilisers: NPK at the recommended application rate, starch–urea matrix (SUM) + PK, neem‐coated urea + PK and urea alone (urea without coating) were used. Gas samples were collected from the field at weekly intervals with the static chamber technique. N2O emissions from different treatments ranged from 11.58 to 215.81 N2O‐N μg/m2/h, and seasonal N2O emissions from 2.83 to 3.89 kg N2O‐N/ha. Compared with other fertilisers, N2O emissions were greatest after the application of the conventional NPK fertiliser. Moreover, SUM + PK reduced total N2O emissions by 22.33% (P < 0.05) compared with NPK during the rice‐growing period (P < 0.05). The results indicate a strong correlation between N2O emissions and soil organic carbon, nitrate, ammonium, above‐ and below‐ground plant biomass and photosynthesis (P < 0.05). The application of SUM + PK in rice fields is suitable as a means of reducing N2O emissions without affecting grain production. 相似文献
2.
Sundareshwar PV Murtugudde R Srinivasan G Singh S Ramesh KJ Ramesh R Verma SB Agarwal D Baldocchi D Baru CK Baruah KK Chowdhury GR Dadhwal VK Dutt CB Fuentes J Gupta PK Hargrove WW Howard M Jha CS Lal S Michener WK Mitra AP Morris JT Myneni RR Naja M Nemani R Purvaja R Raha S Vanan SK Sharma M Subramaniam A Sukumar R Twilley RR Zimmerman PR 《Science (New York, N.Y.)》2007,316(5822):204-205
3.
Bandyopadhyay S Lodh C Sarkar M Ghosh MK Bera AK Bhattacharyya D Mondal DK Baruah KK 《Tropical animal health and production》2012,44(5):1063-1072
Of 273 samples (rectal swab) collected from free-ranging yaks of Tawang district, Arunachal Pradesh, 42 Shiga toxin-producing
Escherichia coli (STEC), six enteropathogenic E. coli (EPEC) and 27 enterotoxigenic E. coli (ETEC) strains were isolated. All the STEC and EPEC strains were further investigated for respective stx variants (for STEC only) and additional putative virulence factors. The 27 ETEC strains were also screened for characteristic
enterotoxin gene(s) and colonization factors. Occurrence of ETEC was significantly (p < 0.05) higher in the diarrheic yaks and yaks of less than 1 year of age. Majority of enterovirulent E. coli isolates were resistant to amikacin, azithromycin, chloramphenicol, colistin, doxycycline, furazolidone, nalidixic acid,
nitrofurantoin, streptomycin and tetracycline. Dendrogram, constructed with molecular fingerprinting profiles obtained from
RAPD (Randomly Amplified Polymorphic DNA) and ERIC (Enterobacterial Repetitive Intergenic Consensus) PCR, placed the isolates
in different clusters irrespective of their serotypes, virulence gene and drug resistance pattern. Collectively, the study
indicates that yaks, being a potential reservoir of multidrug resistant STEC and EPEC, may represent significant risk to public
health in this region. Higher recovery of ETEC isolates from yaks with diarrhea points out that ETEC may be a major determinant
for repeated occurrence of diarrhea in yaks. 相似文献
4.
K. K. Baruah A. Dhali A. Mech B. Bora J. Das R. Bora M. Mondal B. C. Sarmah B. C. Deka C. Rajkhowa 《Journal of animal physiology and animal nutrition》2013,97(6):1051-1058
The effect of concentration and addition method of glycerol on the quality of cryopreserved mithun (Bos frontalis) spermatozoa was investigated. Semen samples were collected from five healthy mithun bulls through rectal massage method and cryopreserved in liquid nitrogen. The samples were diluted in Tris–egg yolk–glycerol extender, equilibrated for 4 h at 4 °C and loaded into 0.50‐ml straws. The straws were then frozen in liquid nitrogen vapour for 10 min and finally plunged into liquid nitrogen for storage. The required amount of glycerol was added into the diluted samples either in a single dose (3%, 4%, 5%, 6% or 7%; added at 37 °C immediately before equilibration) or in split doses (5%, 6% or 7%; the total amount was divided into four equal parts, and a part was added at 37 °C immediately before equilibration, and the remaining parts were added subsequently at 1, 2 and 3 h of equilibration at 4 °C). In the single‐dose addition method, following freeze‐thawing, greater (p < 0.05) motility (%) and proportion of live spermatozoa with intact acrosome (LSIA, %) in 5% glycerol (40.6 ± 1.7 and 43.4 ± 1.8 respectively) and lesser (p < 0.05) total morphological abnormalities (%) in 5% (14.1 ± 0.8) and 6% (13.7 ± 1.0) glycerol were observed compared to the other glycerol concentrations. In the split‐dose addition method, following freeze‐thawing, greater (p < 0.05) motility (%) and LSIA proportion (%) were found in 5% (50.2 ± 1.9 and 53.3 ± 1.8 respectively) compared to 6% or 7% glycerol, but the total morphological abnormalities were not different among the glycerol concentrations. In addition, in all the glycerol concentrations, better (p < 0.05) post‐freeze‐thaw motility and LSIA proportions were observed when glycerol was added in split doses compared to a single dose. In conclusion, Tris–egg yolk extender with 5% glycerol added in split doses was found most suitable for cryopreserving mithun sperm. 相似文献
5.
Effects of low‐density lipoproteins as additive on quality parameters and oxidative stress following cryopreservation of mithun (Bos frontalis) spermatozoa 下载免费PDF全文
下载免费PDF全文 P Perumal SK Srivastava SK Ghosh KK Baruah S Bag JS Rajoria K Kumar C Rajkhowa M Pande N Srivastava 《Reproduction in domestic animals》2016,51(5):708-716
Artificial breeding of mithun poses several challenges including lack of standard protocol for cryopreservation of spermatozoa. This is further complicated by harmful effects of hen's egg yolk (EY) as additive in extender. Purified low‐density lipoproteins (LDL) extracted from EY have been shown as beneficial over EY extender for long‐term semen storage in several species. This investigation explored use of LDL versus EY on semen quality and oxidative stress following freezing–thawing of spermatozoa. A total of 25 of 50 ejaculates based on biophysical parameters were selected for the experiment. After diluting with the Tris‐citrate‐glycerol (TCG) extender, each sample was split into three equal aliquots: Group I, control, EY; Group II and Group III contained 8% and 10% purified LDL, respectively. Frozen–thawed samples were evaluated for motility parameters (progressive, and in the bovine cervical mucus penetration test [BCMPT]), viability, sperm and nuclear abnormality, acrosome integrity, and enzymatic (leakage of intracellular contents) and biochemical (oxidative stress) profiles and in vitro fertility (IVF) assay. Study revealed a significant (p < .05) improvement in viability, sperm and nuclear abnormality, acrosome integrity, motility (progressive and in cervical mucus), cholesterol content, and reduction in the leakage of intracellular enzymes in Group II. Moreover, intactness of acrosome and biochemical membranes was protected significantly (p < .05) in addition to significant (p < .05) improvement in binding per cent and binding index in IVF assay in extender containing 8% LDL. These results demonstrate that although cryopreservation of mithun's spermatozoa in EY was comparable with other species, addition of 8% LDL holds a clear advantage over EY or 10% LDL. 相似文献
6.
Sarma K Pal AK Sahu NP Dalvi RS Chatterjee N Mukherjee SC Baruah K 《Fish physiology and biochemistry》2012,38(2):499-509
Two experiments, one short-term and one long-term, were conducted to elucidate the acute and chronic effects, respectively,
of endosulfan exposure on the haemato-immunological and histopathological responses of Channa puncatatus. In the short-term study, fish were exposed to sublethal endosulfan (8.1 μg l−1) for 12, 24, 36, 48, 72 and 96 h. In the long-term study, fish were fed with normal diet and simultaneously either exposed
to endosulfan (1.2 μg l−1) for 90 days or not. Results showed that the ascorbic acid levels in both the liver and the muscle decreased significantly
(P < 0.05) by acute and chronic endosulfan exposure. The haemoglobin (Hb) level reduced significantly (P < 0.05) by 15.5% within 12 h of acute endosulfan exposure, further decreased by 25.8% after 24 h of exposure, however, thereafter
the values increased and at the end of 72 h returned to normal levels. Almost similar trend was observed for the erythrocyte
(RBC) count. The WBC count and the nitroblue tetrazolium (NBT) value showed a general increasing trend with increase in the
duration of acute endosulfan exposure. The chronic exposure of C. punctatus to endosulfan significantly (P < 0.05) lowered the Hb level, RBC and WBC counts, NBT reduction value and the plasma parameters such as plasma protein, albumin
(A) and globulin (G) compared with that of the control (except for A/G ratio). Endosulfan exposure also severely altered the
liver histological structure. Overall results indicated that both short-term acute and long-term chronic endosulfan exposure
had a significant impact on the haemato-immunological parameters and tissue histopathology of C. punctatus. 相似文献
7.
This paper presents the simultaneous measurement of atmospheric concentration of gaseous NH3, SO2 and NO2, and particulate NH 4 + released from the mining activities of coal-mine area, Tirap colliery, Margherita (Assam). Gas samples were collected by impinger method and were analyzed colorimetrically. The vapor-phase concentration of NH3, SO2, and NO2 range between 4.7?C40.03, 1.47?C6.14, and 1.92?C2.40???g/m3. The NH 4 + concentration in PM10 and PM2.5 ranges between 0.02?C0.07 and 0.008?C0.03???g/m3, respectively. Moderately high concentrations of NH3 and SO2 on the first day were due to the coal-burning activity near the sampling site, while the low concentration of NO2 is due to less vehicle density near the sampling point. All the observed concentrations are below than those reported for the urban areas and the prescribed limit fixed by National Ambient Air Quality Standard, India. Study indicates that ammonia is the major neutralizing agent for sulfate and nitrate ions present in the particulate matter during mining activities. 相似文献
8.
Das Krushna Chandra Haque Nazrul Baruah K. K. Rajkhowa C. Mondal M. 《Tropical animal health and production》2011,43(1):209-214
A study was conducted to compare the nutrient utilization, growth, and rumen enzyme profile of mithun (Bos frontalis) and Tho-tho cattle (Bos indicus) reared in the same feeding and managemental conditions. For the purpose, male mithun (n = 8) and male Tho-tho cattle (n = 8) of 1.5 years age, selected from the farm of National Research Centre on Mithun, Nagaland, India, were fed on mixed-tree-leaves-based
ration as per the requirement of NRC (2001) for cattle for 12 months. Average daily gain (ADG), average dry matter intake (DMI), and feed conversion ratio (FCR) for
all animals were recorded. A metabolic trial was conducted at 6 months of the experiment to assess the digestibility coefficient
of different nutrients and nutritive value of ration. At 12 months of the experiment, rumen liquor was collected from all
animals and analyzed for rumen enzyme profiles, viz., carboxymethylcellulase, xylanase, α-amylase, β-glucosidase, α-glucosidase,
urease, and protease. It was found that ADG (507.8 g vs 392.8 g), DM intake (6.59 vs 5.85 kg/day) and DMI/W0.75 (98.75 g vs 91.00 g/day), crude protein intake (780 vs 700 g/day), and total digestible nutrient intake (3.65 vs 3.32 kg/day)
were higher (p < 0.05) in mithun than cattle. The nitrogen balance was higher and FCR was better (p < 0.05) in mithun compared with cattle. The digestibility coefficient of different nutrients was similar (p > 0.05) between the species. The microbial enzyme profiles of mithun and cattle were not different (p > 0.05). The better growth performance of mithun than cattle as found in the present study clearly indicates that the mithun
has higher genetic potential for growth than Tho-tho cattle of north-eastern hilly region of India. 相似文献
9.