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1.
NADPH-dependent inhibition of hepatic microsomal carboxylesterase by a derivative of monocrotophos (coded as RPR-5) was studied in rat and Japanese quail as a measure of monooxygenase-catalysed activation of RPR-5. There was NADPH-dependent inhibition of hepatic microsomal α-naphthyl acetate esterase (carboxylesterase) both in rat and quail, indicating monooxygenase-catalysed formation of an oxon that subsequently phosphorylated α-NaE. The pattern of in-vitro metabolism of 14C-labelled RPR-5 by 11000g supernatant (11-S), microsomes and 105000g supernatant (105-S) fractions of rat and quail livers suggested the involvement of microsomal monooxygenases and carboxylesterases. A radiolabelled metabolite (M2) was tentatively identified as an acid produced by carboxyl esterase attack. In rat, metabolism by microsomal and cytosolic (105-S) carboxylesterases appeared to predominate with relatively little oxidative metabolism. In quail, putative microsomal carboxylesterase hydrolysis of RPR-5 was much lower than in the rat with almost neglible hydrolysis by cytosolic fractions. Also, production of M2 by quail microsomes was substantially reduced after addition of NADPH, suggesting inhibition of a carboxyl esterase by the oxon of RPR-5. Differences in this detoxification of RPR-5 between rat and quail may be an important factor in determining selective toxicity and the results underline the importance of relating metabolism to toxicity when selecting animal models for toxicity testing. 相似文献
2.
Taek-Ryoun Kwon Zamin Shaheed Siddiqui Phil J.C. Harris 《Journal of plant nutrition》2013,36(4):644-667
ABSTRACT Effects of three supplemental calcium (Ca++; 2.5, 5.0, and 10 mole m?3) concentrations on ion accumulation, transport, selectivity, and plant growth of salt-sensitive species, Brassica rapa ‘Sani’ in saline medium were investigated. Supplemental Ca++ in the presence of 125 mol m?3 sodium chloride (NaCl) did not improve the dry weight and leaf area indicating no role played by Ca++ in the alleviation of salinity induced growth inhibition. However, calcium chloride (CaCl2) did significantly affect sodium (Na+), potassium (K+), and Ca++ contents of roots and shoots. The ion contents of shoots were significantly greater than those of roots per g dry weight, indicating ion transportation to shoots is greater than ion accumulation in roots. Use of CaCl2 in 125 mol m?3 NaCl reduced the Na+ content but increased K+ and Ca++ contents in shoots. Sodium contents in shoots differed among the supplemental Ca++ treatments indicating the role of CaCl2 in Na+ ions transportation. Calcium content in shoots declined significantly in the control treatment (0 CaCl2) but increased significantly in 10 mol m?3 CaCl2. The root also showed the effects of Ca++ on the reduction of Na+ content and the increase of K+ and Ca++ content. Unexpectedly, 5 mol m?3 CaCl2 induced the highest Na+ content in roots at 16 days after treatment. Supplemental CaCl2 application influenced the K+ or Ca++ selectivity over Na+ in two ways, ion accumulation at roots and transport to shoots. However, high CaCl2 treatments allowed greater Ca++ selectivity over Na+ than low CaCl2. Likewise, high supplemental CaCl2 showed higher K+ selectivity over Na+ than low CaCl2. A marked increase in K+ versus Na+ selectivity for the transport process occurred at 10 mol m?3 CaCl2 treatments. The roots and shoots exhibited higher K+/Na+ and Ca++/Na+ ratios in high CaCl2 treatment than in low. The results are discussed in context to supplemental Ca++ concentrations, ions accumulation, transportation and selectivity of salt sensitive Brassica rapa cultivar. 相似文献
3.
Abdul Qayyum Siddiqui Yousef S. Al-Hafedh Ahmed H. Al-Harbi Seikh A. Ali 《Journal of the World Aquaculture Society》1997,28(1):106-112
Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m2 , grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m2 (29.6 9). and lowest at 20 prawns/m2 (17.4 g). Total yield increased from 135 g/m2 (1,350 kg/ha) at a density of 5 prawns/m2 to 261 g/m2 (2,610 kg/ha) at density 15/mz to 245 g/m2 (2,450 kg/ha) at 20/mz . Feed conversion ratios were high and ranged from 3.7 (5 prawns/m2 ) to 5.6 (20 prawns/m2 ).
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m2 for 112 d, the all-male population had the best growth performance and feed conversion ratio, followed by the mixed-sex and all-female populations. The all-male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m2 (1,590 kg/ha); the mixed-sex population had 90% marketable prawns and the yield was 135 g/mz (1,350 kg/ha); and the all-female population had 75% marketable prawns with an average yield of 108 g/m2 (1,080 kgha). 相似文献
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m
4.
Root-exudates of Neem/Margosa and Bakain/Persian lilac brought about considerable mortality ofHoplolaimus indicus, Helicotylenchus indicus, Tylenchus filiformis, Tylenchorhynchus brassicae, Rotylenchulus reniformis andMeloidogyne incognita, however, to varying extent. The root-exudate of Neem was more toxic to nematodes than that of Bakain. The root-exudates also inhibited larval hatch ofM. incognita. 相似文献
5.
Richa Sood Rekha Khandia Sandeep Bhatia Divakar Hemadri Manoj Kumar Sharan S. Patil Atul K. Pateriya Arshi Siddiqui Malkanna Sanjeev Kumar Mudalagiri Dasappa Venkatesha Diwakar D. Kulkarni 《Tropical animal health and production》2014,46(6):1037-1043
Malignant catarrhal fever (MCF) is a fatal herpesvirus infection of domestic and wild ruminants, with a short and dramatic clinical course characterized primarily by high fever, severe depression, swollen lymph nodes, salivation, diarrhea, dermatitis, neurological disorders, and ocular lesions often leading to blindness. In the present study, fatal clinical cases of sheep associated malignant catarrhal fever (SA-MCF) were identified in cattle in the state of Karnataka. These cases were initially presented with symptoms of diarrhea, respiratory distress, conjunctivitis, and nasal discharges. Laboratory diagnosis confirmed the detection of ovine herpesvirus-2 (OvHV-2) genome in the peripheral blood samples of two ailing animals. The blood samples collected subsequently from sheep of the neighboring areas also showed presence of OvHV-2 genome indicating a nidus of infection in the region. The positive test results were further confirmed by nucleotide sequencing of the OIE approved portion of tegument gene as well as complete ORF8 region of the OvHV-2 genome. Phylogenetic analysis based on the sequence of the latter region indicated close genetic relationship with other OvHV-2 reported elsewhere in the world. 相似文献
6.
The influence of sex ratio, stocking density and age of hybrid tilapia (Oreochromis niloticus X O. aureus) brood fish on seed production in concrete tanks were evaluated in 1992 and 1993. A sex ratio of 1:2 and 1:3 (male: female) and a density of 2 fish m-2 gave the best result with respect to number of seed female-1 day-1 and number of seed kg-1-1 female day-1. Maximum seed production female-1 day-1 was recorded for 3-year-old females and the minimum for 1-year-olds, but in terms of seed kg-1 female day-1 and seed m-2 day-1, 1-year-olds produced the maximum number of seed followed by 2-, 3- and 4-year-old females. Seasonal pattern in seed production was apparently influenced by season and temperature. From the first harvest on 21 April 1993 the production increased gradually, reaching a peak during the third harvest and a second peak during the sixth harvest. Thereafter seed production gradually decreased, reaching a minimum during the tenth harvest on 27 October 1993. No seed were found during the last harvest of 18 November 1993. Maximum production coincided with the highest water temperature of around 28°C. 相似文献
7.
Of six fractions of human plasma tested, only Cohn's fraction IV-4 was effective for the replacement of whole plasma from monkey (Macaca mulatta) for the in vitro culture of Plasmodium knowlesi. The effects observed on multiplication and morphology of parasites suggest a specific role of some substance or substances in fraction IV-4. 相似文献
8.
Siddiqui N Price S Hope J 《Comparative immunology, microbiology and infectious diseases》2012,35(3):219-226
Bovine tuberculosis is a disease of increasing incidence in the UK causing major economic losses and with significant impact on bovine and, potentially human health: the causative agent Mycobacterium bovis is a zoonotic pathogen. Neonatal vaccination with the attenuated M. bovis Bacille Calmette Guerin (BCG) vaccine confers a significant degree of protection in cattle, and is a widely used control strategy for human TB. The adaptive immune system is relatively immature in neonates and increased numbers of innate effector cells present in young animals and human infants may compensate for this, enabling effective immune responses to vaccination. Natural killer cells and subsets of γδ TCR+ T lymphocytes secrete high levels of interferon gamma and can interact with antigen presenting cells to promote both innate and adaptive immune responses. These cell populations may be pivotal in determining immune bias following neonatal vaccination with BCG. 相似文献
9.
Shisham (Dalbergia sissoo) is an important multipurpose tree with great economic importance, but this tree has been devastated by dieback disease. Seedlings and asexually propagated (cuttings) plants were artificially inoculated with four fungi (Fusarium solani, Botryodiplodia theobromae, Curvularia lunata and Ganoderma lucidum) to evaluate the potential role of these fungi in shisham dieback disease. Results at 2 years revealed that highest disease was caused by inoculation of F. solani (31.39%), followed by B. theobromae (19.042%) and C. lunata (12.22%), but no dieback disease was caused by G. lucidum. During both years, seedlings exhibited greater susceptibility to disease (17.24%) compared to cuttings (7.83%). In particular, F. solani caused more disease in seedlings (46.18%) compared to cuttings (16.61%). With the F. solani inoculations, maximum disease rate was observed at 8 weeks post‐inoculation both in seedlings (77%) and in cuttings (31%), but the maximum disease increase was observed at 4–5 weeks post‐inoculation. Analysis of variance showed significant differences among the different fungi and also between seedlings and cuttings. F. solani can be considered as a major fungal pathogen contributing to dieback disease of shisham, and asexual propagation can reduce the severity of dieback. 相似文献
10.
Six-week-old Nile tilapia (Oreochromis niloticus) fry with an average weight (SD) of 0.51(0.2) g were reared for 140 days on five formulated, isocaloric diets of different protein levels (25, 30, 40 and 45% by dry weight). Fish fed diets of higher protein levels (40 and 45%) showed better growth and feed conversion ratio than those on lower protein levels. Fast-growing fish matured earlier. Maturation rate was affected by the dietary protein levels. Males matured earlier than females: the first mature males were recorded when they were 14 weeks old, whereas the females matured after 18 weeks. In both sexes, mean percentage of mature fish rose with increasing dietary protein level, the percentage of mature males being higher than that of the females. Similarly, the percentage of mature fish rose with the increasing age of fish, with more than 50% males and females mature at the age of 22 and 24 weeks, respectively, the exception being the 25% protein diet fed fish, where the percentage of mature fish was below 50%. In all treatments, spawning was initiated when the fish were 22 weeks old. Smallest size at spawning of males and females was 9.2 cm (13.1 g) and 8.1 cm (8.9 g), respectively, and dietary protein levels influenced the size of fish at first maturity. For both sexes, no difference was found in the gonado-somatic index (GSI) among different treatments. Fecundity increased with increasing dietary protein levels, but significant differences were found only between 40–45% and 25–35% dietary protein levels. The relative fecundity (eggs g–1 female) was higher at the lower dietary protein levels (25–35%) than at the higher dietary protein levels (40–45%). The dietary protein levels did not have any significant influence on the size and weight of mature eggs. The chemical composition of fish and mature ovaries was significantly influenced by the dietary protein level. 相似文献