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141.
P K Howard P K Chakraborty J C Camp L D Stuart D E Wildt 《Journal of animal science》1983,57(6):1517-1524
Pituitary-ovarian function was analyzed in a strain of miniature swine previously shown to produce a low ovulation rate resulting in the formation of only 8.6 corpora lutea (CL)/animal. Five multiparous (M) and four nulliparous (N) miniature pigs with a mean inbreeding coefficient of .39 were monitored for estrous behavior through four consecutive estrous cycles. Daily blood samples were collected from 5 d before to 5 d after the onset of the second, third and fourth estrus and at 48-h intervals during the remainder of the second and third estrous cycle. Laparoscopy was used to examine the ovaries 1 and 5 d after onset of the third estrus and 2 d after the beginning of the fourth estrus. For the entire group, temporal fluctuations among serum estradiol-17 beta, luteinizing hormone (LH) and progesterone concentrations and sexual behavior were similar to previously published data in standard swine breeds. Although the mean lengths of the estrous cycle were not different (P greater than .05) between parity subgroups (M, 23 +/- 1.3 vs N, 22 +/- .7 d), multiparous pigs were in estrus longer (P less than .05) than nulliparous females (M, 3.7 +/- .2 vs N, 2.2 +/- .4 d). Parity subgroups were similar with respect to the mean number of follicles forming CL (M, 8.8 +/- .7 vs N, 9.2 +/- .2). Although an average of 6.2 +/- 2.1 CL had formed by 24-h after onset of estrus in the nulliparous subgroup, no CL were detected in the multiparous subgroup at this time.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
142.
S. Chakraborty † R. Ghosh M. Ghosh C. D. Fernandes M. J. Charchar S. Kelemu 《Plant pathology》2004,53(4):375-386
Data were collected and analysed from seven field sites in Australia, Brazil and Colombia on weather conditions and the severity of anthracnose disease of the tropical pasture legume Stylosanthes scabra caused by Colletotrichum gloeosporioides . Disease severity and weather data were analysed using artificial neural network (ANN) models developed using data from some or all field sites in Australia and/or South America to predict severity at other sites. Three series of models were developed using different weather summaries. Of these, ANN models with weather for the day of disease assessment and the previous 24 h period had the highest prediction success, and models trained on data from all sites within one continent correctly predicted disease severity in the other continent on more than 75% of days; the overall prediction error was 21·9% for the Australian and 22·1% for the South American model. Of the six cross-continent ANN models trained on pooled data for five sites from two continents to predict severity for the remaining sixth site, the model developed without data from Planaltina in Brazil was the most accurate, with >85% prediction success, and the model without Carimagua in Colombia was the least accurate, with only 54% success. In common with multiple regression models, moisture-related variables such as rain, leaf surface wetness and variables that influence moisture availability such as radiation and wind on the day of disease severity assessment or the day before assessment were the most important weather variables in all ANN models. A set of weights from the ANN models was used to calculate the overall risk of anthracnose for the various sites. Sites with high and low anthracnose risk are present in both continents, and weather conditions at centres of diversity in Brazil and Colombia do not appear to be more conducive than conditions in Australia to serious anthracnose development. 相似文献
143.
Sanis Juliet Animesh K Chakraborty Kishori M Koley Tapan K Mandal Anjan Bhattacharyya 《Pest management science》2001,57(3):311-319
A study of the toxico‐kinetics, recovery percentage from different substrates, cytotoxicity and role of cytochrome P450 and b5 of liver microsome in the metabolism of deltamethrin were carried out in female black Bengal goat. The ALD50 value of deltamethrin in goat by intravenous route lies between 0.2 and 0.6 mg kg?1. Intravenous disposition kinetics using a dose of 0.2 mg kg?1 showed that the maximum blood concentration of deltamethrin was recorded at 0.5 min, followed by rapid decline, and a minimum concentration was detected at 6 min after administration. The following values were obtained : Vdarea 0.148 (± 0.02) litre kg?1; t1/2 (α) 0.22 (± 0.02) min; t1/2 (β) 2.17 (± 0.37) min; Kel 1.05 (± 0.24) min?1; AUC 4.30(± 0.45) µg min ml?1; ClB 0.05 (± 0.006) litre kg?1 min?1; T~B 1.93 (± 0.58); fc 0.40(± 0.05). After 10 min, liver retained the maximum residue, and heart, adrenal gland, kidney, spleen, fat and brain also held the insecticide; liver, fat, heart and spleen retained residue after 30 min, and bone, liver and fat retained residue after 60 min of intravenous administration. Oral absorption of deltamethrin was poor and inconsistent, and approximately 65% of administered dose was recovered from faeces and gastrointestinal contents. The excretion of deltamethrin through urine was meagre, and only 0.01 and 0.013% of the administered dose was recovered after 3 and 5 days of oral administration respectively. All the tissues retained the residue after 3 days; while fat, rumen, reticulum, omasum, abomasum, large and small intestine and bone retained the residue after 5 days of oral administration; and the percentage recoveries were 1.73 and 0.027 respectively. Deltamethrin reduced the level of cytochrome P450 content of liver microsomal pellet of goat after 5 days of oral administration. Histopathological examination of liver, kidney, heart, spleen brain and lung sections of treated goats did not reveal any pathological changes. © 2001 Society of Chemical Industry 相似文献
144.
Subhasish K. Chakraborty Anjan Bhattacharyya Ashim Chowdhury 《Pest management science》1993,37(1):73-77
Sunlight irradiation of hydramethylnon in aqueous media of different pH values resulted in 80-94% transformation within 10h. The rate of disappearance of the insecticide was affected marginally by the initial pH of the reaction medium. After 10 h irradiation, eight photoproducts were formed. Three products were isolated as pure crystalline substances and the structures of two of these (I & III) were characterised by mass and NMR spectroscopy. The reaction mechanisms involved in the formation of photoproducts are discussed. 相似文献
145.
146.
Batches of glasshouse-grown flowering sorghum plants were placed in circular plots for 24 h at two field sites in southeast Queensland, Australia on 38 occasions in 2003 and 2004, to trap aerial inoculum of Claviceps africana. Plants were located 20–200 m from the centre of the plots. Batches of sorghum plants with secondary conidia of C. africana on inoculated spikelets were placed at the centre of each plot on some dates as a local point source of inoculum. Plants exposed to field inoculum were returned to a glasshouse, incubated at near-100% relative humidity for 48 h and then at ambient relative humidity for another week before counting infected spikelets to estimate pathogen dispersal. Three times as many spikelets became infected when inoculum was present within 200 m of trap plants, but infected spikelets did not decline with increasing distance from local source within the 200 m. Spikelets also became infected on all 10 dates when plants were exposed without a local source of infected plants, indicating that infection can occur from conidia surviving in the atmosphere. In 2005, when trap plants were placed at 14 locations along a 280 km route, infected spikelets diminished with increasing distance from sorghum paddocks and infection was sporadic for distances over 1 km. Multiple regression analysis showed significant influence of moisture related weather variables on inoculum dispersal. Results suggest that sanitation measures can help reduce ergot severity at the local level, but sustainable management will require better understanding of long-distance dispersal of C. africana inoculum. 相似文献
147.
ABSTRACTAntioxidant potential, total phenolic content, and high performance liquid chromatography-based solvent extract fingerprints of phenolic constituents of brown seaweeds, Turbinaria conoides and Turbinaria ornata, were evaluated. The ethyl acetate (EtOAc) fraction of the seaweeds registered greater phenolic content and antioxidant activities. Salicylic acid, gallic acid, quercetin, and syringic acid were predominant in the EtOAc fraction of T. conoides, while the main components in EtOAc fraction of T. ornata were quercetin and salicylic acid. This study demonstrated the candidacy of Turbinaria spp. as a potential source of antioxidant phenolics for use as food supplements and nutraceuticals to deter deleterious free radical-induced disorders and diseases. 相似文献
148.
Kajal Chakraborty Selsa J. Chakkalakal Deepu Joseph Minju Joy 《Journal Of Aquatic Food Product Technology》2013,22(8):1172-1189
ABSTRACTNutritional composition of edible oysters (Crassostrea madrasensis) from the wild and cultured growth habitats from the southwest coast of India were evaluated over 4 years (2008–2011) during the premonsoon season. The important nutritional qualities of this species have been correlated with chlorophyll-a concentration, sea surface temperature, and phytoplankton density in their growth environments. The higher proportions of total polyunsaturated fatty acids, eicosapentaenoic, and docosahexaenoic acids in the edible oysters collected from the wild habitats were significantly correlated with chlorophyll-a concentration revealing the role of the phytoplanktons to contribute to the occurrence of these vital fatty acids. The ideal atherogenic index (AI); thrombogenicity index (TI); hypocholesterolemic/hypercholesterolemic ratio (HH); and balanced quantities of vitamins, minerals, amino acids, and low cholesterol contents qualified C. madrasensis as a potential health food. 相似文献
149.
Kajal Chakraborty Deepu Joseph Selsa J. Chakkalakal P. S. Stephy 《Journal Of Aquatic Food Product Technology》2013,22(6):811-823
ABSTRACTInterannual and seasonal (premonsoon, monsoon, and postmonsoon) variability in the lipid, fatty acids, and total cholesterol content of ribbon fish, Trichiurus lepturus were determined for a period of 4 years (2008–2011) along the southwest (SW) and southeast (SE) coasts of India. The lipidic compositions were studied along with chlorophyll-a concentration and sea surface temperature (SST) data obtained from MODIS and Sea WiFS. The lipid content shows seasonal fluctuations with higher values in the postmonsoon season along the SE coast and during the monsoon in the SW coast. Among polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (DHA) dominated over eicosapentaenoic acid (EPA) throughout the seasons except in winter on the SE coast. The health indices such as atherogenic/thrombogenicity indices, total cholesterol, and hypocholesterolemic/hypercholesterolemic ratio of ribbon fish were found to be ideal, which contributed toward its parameters to be qualified as a potential health food. 相似文献
150.
The development of tea blister caused by Exobasidium vexans in tea (Camellia sinensis) correlates with the reduced accumulation of some antimicrobial metabolites and the defence signals salicylic and jasmonic acids
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L. A. J. Mur B. Hauck A. Winters J. Heald A. J. Lloyd U. Chakraborty B. N. Chakraborty 《Plant pathology》2015,64(6):1471-1483
Blister blight (causal agent, Exobasidium vexans) is an economically devastating disease of tea (Camellia sinensis). To determine what metabolite changes occur with tea blister that could be linked to disease progression, metabolomic approaches were used on E. vexans infected tea from a Darjeeling (India) plantation. Samples were classified according to disease phenotypes, i.e. either healthy or at one of three stages of disease progression. Initial metabolite fingerprinting using Fourier transform infrared (FTIR) spectroscopy indicated that metabolite changes could be related to disease stage. Electrospray ionization mass spectrometry (ESI‐MS) highlighted caffeine and flavonoid metabolism changes as disease progressed. High‐performance liquid chromatography (HPLC) with online photodiode array detection and electrospray ionization‐tandem mass spectrometry (HPLC‐PDA‐ESI/MSn) was used to characterize the caffeine, flavan‐3‐ol, flavone and flavonol profiles. There were increases in quercetin and kaempferol glucosides, kaempferol triglycosides and some catechin‐class antioxidants, but also substantial reductions in apigenin and myricetin glycosides and, particularly, caffeine as disease progressed. The content of important defence hormones, salicylic acid and jasmonic acid, was also reduced in blister blight diseased samples. Thus, E. vexans infections perturb defence signalling and reduce many potentially antimicrobial compounds, such as caffeine, to aid disease progression. 相似文献