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41.
Migratory locusts represent the most important crop pests in Africa and Asia. Because environmental damages are associated with the use of synthetic insecticides in locust and grasshopper control, new environmentally acceptable approaches are becoming increasingly important. The effects of gibberellic acid (GA3), a plant growth regulator, was investigated by topical application and ingestion on the reproductive physiology and ecdysteroids production of the migratory locust Locusta migratoria at concentrations of 125, 625, 3125, 4125, 5125 and 6125 μg/mL. The treatment applied to adult females during the pre-ovipositional phase provokes a significant adverse influence on their reproductive potential. Indeed, GA3 significantly reduced both fecundity and fertility. Gibberellic acid also caused disturbances in the incorporation of the hemolymph metabolites (proteins, carbohydrates and lipids) in the oocyte resulting in a significant reduction in their concentrations in the ovaries. Ecdysteroid production was measured by an enzymo-immunoassay. GA3, administered by ingestion to the adult females, significantly reduced the ecdysteroid titers in ovaries and freshly laid eggs.  相似文献   
42.
Combining ability and heterosis were studied in a 6 × 6 diallel cross to see the nature of gene action in Upland cotton (Gossypium hirsutum L.) during 2002 to 2004. Analysis of variance revealed highly significant differences among all the F1 and F2 hybrid means and their respective six parental values for all the traits examined. In both generations, the mean squares due to general combining ability (GCA) and specific combining ability (SCA) were also highly significant. SCA genetic variances were greater than GCA and more important for the traits, i.e. boll weight, boll number and seed cotton yield per plant, showing the predominance of non-additive gene action. Lint % in both generations and boll weight in F2s only were controlled by additive type of gene action due to maximum GCA variances. Cultivar CIM-1100 was found to be the best general combiner and its utilization produced valuable hybrids with desirable SCA in both generations. F1 and F2 hybrids, viz., CIM-1100 × CRIS-9, CIM-1100 × FH-682, CIM-1100 × BH-36 and CIM-109 × CIM-1100 as high × low and low × high parents performed well in SCA determination, outstanding mean performance and heterosis. Better SCA effects associated with useful heterosis were more pronounced for yield traits. In F1 hybrids, maximum heterosis was observed for seed cotton yield followed by boll number, boll weight and lint %. The heterosis over better parent was +3.13 to +65.63% for bolls per plant, +0.75 to +24.40% for boll weight, +0.82 to +115.22% for seed cotton yield and +0.27 to +3.88% for lint %. Involvement of CIM-1100 in most of the F1 and F2 hybrids resulted in the synthesis of superior genotypes for most of the traits studied. Inbreeding depression was elevated in good performing hybrids and was the highest for seed cotton yield. Highest yielding F1 hybrids yielded lesser in the subsequent generation due to over-dominance and inbreeding depression, whereas moderate yielding F1 hybrids were found more stable even passing through process of segregation due to additive gene action. The combined performance of F1 and F2 hybrids could be a good indicator to identify the most promising populations to be utilized either as F2 hybrids or as a resource population for further selection.  相似文献   
43.
The influence of all-plant-based diet on fingerling blunt snout breams (Megalobrama amblycephala) was tested by examining growth performance, anti-stress properties and related gene expression. Healthy fish were randomly divided into triplicate groups per dietary treatment and fed with different formulated diets. The results showed that both weight gain, specific growth rate and protein efficiency ratio of all-plant-based diet group were significant higher than those of the control (p < 0.05). In contrast, FCR of all-plant-based diet group was significantly lower than that of the control (p < 0.05). Therefore, all-plant-based diets could not affect the growth performance of blunt snout breams. Compared to the control group, the lysozyme levels in serum and mucus, and glutamic-oxaloacetic transaminase activities in serum and liver decreased significantly (p < 0.05). In contrast, the glutamic-pyruvic transaminase activities in serum and liver increased significantly (p < 0.05). For blunt snout breams fed with all-plant-based diets, the superoxide dismutase activities in mucus, serum and liver as well as catalase activity in serum and liver were decreased significantly (p < 0.05) comparing with that of the control group. But malondialdehyde contents were higher (p < 0.05) in serum and liver than that of control group. The expression of HSC70 mRNA increased significantly (p < 0.05) in blunt snout breams fed with all-plant-based diet, whereas the HSP70 mRNA expression decreased significantly (p < 0.05) when compared with control group. In conclusion, all these results indicated that the application of all-plant-based diet could decrease the anti-stress properties (non-specific immunity, stress resistance and antioxidant ability) and HSP70 mRNA expression in blunt snout breams fingerling. Although all-plant-based diets could not affect the growth performance of blunt snout breams, the application of all-plant-based diet should be discreet in the production practice.  相似文献   
44.
Effects of varying protein‐to‐energy (P/E) ratios on growth performance, nutrient retention, body composition, and digestive enzyme activities of Singhi, Heteropneustes fossilis (7.90 ± 0.40 g; 9.40 ± 0.20 cm) were evaluated. Six experimental diets (350Low, 350High, 400Low, 400High, 450Low, and 450High) in a 3 × 2 factorial design were formulated to contain three protein levels (350, 400, and 450 g/kg crude protein) and two energy levels (4.07 and 4.54 kcal/g gross energy [GE]) to provide six different dietary P/E ratios (86.1, 77, 98.3, 88, 110.6, and 99 mg protein/kcal GE). The diets were hand‐fed to triplicate groups of fish for 84 d to apparent satiation at two feeding frequencies. Live weight gain, feed conversion ratio, protein retention efficiency, energy retention efficiency, somatic indices, and digestive enzyme activities were maximized by the groups fed on 400 g/kg protein with 4.07 kcal/g GE in diet 400Low with a P/E ratio of 98.3 mg/kcal energy. The results indicate that 400 g/kg of dietary protein and 4.07 kcal/g of dietary GE with a P/E ratio of 98.3 mg protein/kcal energy is optimum for achieving efficient growth, feed conversion, and nutrient retention in H. fossilis.  相似文献   
45.
The objective of this study was to identify allelic variations at Glu-1 loci of wheat (Triticum aestivum L.) advanced lines derived from hybridization of bread wheat and synthetic hexaploid wheats (2n = 6x = 42; AABBDD). Locally adapted wheat genotypes were crossed with synthetic hexaploid wheats. From the 134 different cross combinations made, 202 F8 advanced lines were selected and their HMW-GS composition was studied using SDS-PAGE. In total, 24 allelic variants and 68 HMW-GS combinations were observed at Glu-A1, Glu-B1, and Glu-D1 loci. In bread wheat, the Glu-D1 locus is usually characterized by subunits 1Dx2+1Dy12 and 1Dx5+1Dy10 with the latter having a stronger effect on bread-making quality. The subunit 1Dx5+1Dy10 was predominantly observed in these advanced lines. The inferior subunit 1Dx2+1Dy12, predominant in adapted wheat germplasm showed a comparative low frequency in the derived advanced breeding lines. Its successful replacement is due to the other better allelic variants at the Glu-D1 locus inherited in these synthetic hexaploid wheats from Aegilops tauschii (2n = 2x = 14; DD).  相似文献   
46.
Three ellagitannins and one disulfated flavonol were isolated from the aerial parts of Reaumuria vermiculata L. Besides that, 16 known compounds were characterized as well. The structures of all compounds were elucidated on the basis of spectroscopic data including 1D and 2D NMR and ESI HR-FTMS. The in vivo antioxidant activity using the oxygen radical absorbance capacity (ORAC) method, of the extract, its column fractions and two of the isolated ellagitannins was accomplished. In addition, a possible cytotoxicity of the extract and two of the new ellagitannins on HaCaT human keratinocytes and the activity of both compounds against the prostate cancer cell line (PC-3) were also assessed, whereby a potent cytotoxicity with IC(50) less than 1μg/ml was determined for both compounds. Besides, the extract exhibited a potential cytotoxic effect against four different solid tumor cell lines, namely liver (Huh-7), colorectal (HCT-116), breast (MCF-7) and prostate (PC-3). The IC(50)s were found to be substantially low (ranged from 1.3±0.15 to 2.4±0.22μg/ml) with relatively low resistance possibility reaching to 0% in the case of Huh-7 cell.  相似文献   
47.
Viruses belonging to the Nodaviridae family cause disease worldwide among a large number of species of marine fish, and have been described in all continents. In the present study, a total of 69 farmed Tunisian sea bass (Dicentrarchus labrax) and 24 sea bream (Sparus aurata) samples were tested monthly for the detection of betanodavirus. The virus was identified in both species using indirect immunofluorescence assays (IFAT) and RT-PCR. In addition sequence analysis of part of the coat protein gene indicated that both species were infected by highly related, but distinct, strains belonging to the RGNNV genotype. The sequence of the coat protein gene of several strains was identical but up to 9 different sequences were detected in a single farm. In addition, viral sequences obtained from fish that were held at lower temperature (<20°C) were distinct from the rest of the sequences.  相似文献   
48.
Equine babesiosis is a tick-borne protozoal disease of horses caused by Theileria equi and Babesia caballi. The disease is endemic in most tropical and subtropical areas. The aim of this paper is to assess the antioxidant status, lipid peroxidation, and oxidation products of nitric oxide (NO) in horses and mules naturally infected with T. equi and B. caballi. East and Southeast Anatolian horses and mules living in rural region of the Eastern border of Turkey were used as the material for this study. These animals are used as pack animal (3–7 years of age). Infected animals were in acute or subacute infection period. In the current study, malondialdehyde (MDA), oxidation products of NO (nitrate and nitrite), serum glutathione (GSH), vitamin E, and retinol levels were analyzed in 58 equids (horse and mule) infected with T. equi and B. caballi as well as in 44 healthy equids. Compared with controls, the level of MDA and nitrate increased significantly (P < .01, P < .05, respectively), whereas GSH concentration and levels of vitamin E decreased significantly (P < .01). There was no significant change in the level of nitrite and retinol between two groups. The results of the current study suggest that in equids infected with T. equi and B. caballi, this alteration in the lipid peroxidation, oxidants, and antioxidants may be related to the host's defenses against parasitic infection and may play a central role in the pathologic conditions associated with babesiosis.  相似文献   
49.
Diazinon is an organophosphate insecticide has been used in agriculture and domestic for several years. Vitamin E (200 mg/kg, twice a week), diazinon (10 mg/kg, per day), and vitamin E (200 mg/kg, twice a week)+diazinon (10 mg/kg, per day) combination was given to rats orally via gavage for 7 weeks. Body and heart weights, malondialdehyde (MDA) level in heart tissue and ultrastructural changes in myocardial cells were investigated at the end of the 1st, 4th, and 7th weeks comparatively with control group. When diazinon-treated group was compared to control group body and heart weights were decreased significantly at the end of the 4th and 7th weeks. It was observed that, at the end of 1st, 4th, and 7th weeks there was a statistically significant increase in MDA levels when diazinon- and vitamin E +diazinon-treated groups were compared to control group. While at the end of the 1st week statistically significant changes were not being observed, at the end of 4th and 7th weeks statistically significant decrease was detected in MDA levels when vitamin E+diazinon-treated group was compared to diazinon-treated group. In our electron microscopic investigations, while vacuolization and swelling of mitochondria myocardial cells of diazinon-treated rats were being observed, swelling of several mitochondria were observed in vitamin E+diazinon-treated rats. We conclude that vitamin E reduces diazinon cardiotoxicity, but vitamin E does not protect completely.  相似文献   
50.
Dietary histidine requirement of fry African catfish, Clarias gariepinus (2.57 ± 0.02 cm; 0.22 ± 0.03 g) was quantified by feeding casein–gelatin-based isonitrogenous (40% crude protein) and isocaloric (17.90 kJ g−1 gross energy) amino acid test diets with graded levels of histidine (0.25%, 0.30%, 0.35%, 0.40%, 0.45% and 0.50% dry diet) in eighteen 80 L indoor circular aqua-coloured troughs provided with the flow-through system for 12 weeks. Maximum absolute weight gain (2.66), best feed conversion ratio (1.29), highest protein efficiency ratio (1.94), protein retention efficiency (34%) and energy retention efficiency (70.4%) were achieved at 0.40% dietary histidine. Broken-line and non-linear regression models were adopted to assess dietary histidine requirement for C. gariepinus . When analysed using broken-line regression model these parameters were also best at 0.40% dietary histidine corresponding to 1.0% protein, respectively, whereas using second-degree polynomial regression analysis, histidine requirement was obtained at 0.42%, 0.41%, 0.40%, 0.41% and 0.41% of dry diet, corresponding to 1.05%, 1.02%, 1.0%, 1.02% and 1.02% protein respectively. Based on the broken-line and second-degree polynomial regression analyses of the growth and nutrient retention data, optimum histidine requirement of fry C. gariepinus was found to be in the range of 0.40–0.42% dry diet, corresponding to 1.0–1.05% of dietary protein.  相似文献   
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