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1.
The methanol extract of Rumex nepalensis Spreng. roots at the oral dose of 100-400 mg/kg exhibited significant and dose-dependent purgative activity.  相似文献   
2.
Insecticidal fatty acids and triglycerides from Dirca palustris.   总被引:3,自引:0,他引:3  
Five compounds, 1-5, were isolated from the seed hexane extract of Dirca palustris. Compounds 1-3 were triglycerides, and 4 and 5 were linoleic and oleic acids, respectively. Compounds 1-3 were not biologically active; however, 4 (linoleic acid) and 5 (oleic acid) were insecticidal against fourth instar Aedes aegyptii larvae and exhibited potent feeding deterrent activity against neonate larvae of Helicoverpa zea, Lymantria dispar, Orgyia leucostigma, and Malacosoma disstria.  相似文献   
3.
The present study was conducted to evaluate two Indian native chicken breeds, namely, Aseel and Kadaknath for fertility, hatchability, genetic parameters of juvenile growth traits, and semen quality traits at the onset of sexual maturity. The fertility was similar in Aseel (86.96%) and Kadaknath (85.15%); however, a relatively higher hatchability was observed in Kadaknath (77.94%) than Aseel (70.74%). Heritability estimates of body weights at 4 weeks of age were almost similar in Aseel (0.37) and Kadaknath (0.39), while the estimate of body weight at 6 weeks of age was higher in Aseel (0.42) than Kadaknath (0.31). The heritability estimate of shank length at 6 weeks of age was lower in Aseel (0.16) compared to Kadaknath (0.35). The age at first egg in the flock was comparable in Aseel (148 days) and Kadaknath (150 days). Aseel breed with significantly (P ≤ 0.001) higher body weight, absolute and relative testes weights had significantly higher semen volume (P ≤ 0.05) and sperm motility (P ≤ 0.01) but had lower seminal plasma cholesterol level (P ≤ 0.05) as compared to Kadaknath. It can be concluded that there is a scope for genetic improvement of these two native breeds for juvenile growth traits since heritability estimates of these traits were relatively high.  相似文献   
4.
The aim of the present study was to evaluate the antifungal activity of seaweed Champia parvula and identification of active compounds for this action. In this regard, C. parvula crude extracts were obtained from n-hexane, ethyl acetate, chloroform, methanol, and water used to study the antifungal action. Results showed that methanolic extract had potent action against C. albicans, C. tropicalis, T. mentagrophytes, and A.flavus, with the highest inhibition of 16.7 mm found against C. tropicalis. Minimum inhibition concentration at 12.5 and minimum fungal concentration at 25 μg/mL were found in the methanolic extract. Therefore, to identify the bioactive compound for this antifungal action in the methanolic extract, thin-layer chromatography (TLC) and reverse-phase high-performance liquid chromatography (RP-HPLC) were used. The RP-HPLC had three peaks with retention times at 3.30, 3.86, and 4.73 min, showing the presence of ester fatty acid compound. Further, these compounds were characterized by nuclear magnetic resonance (NMR), gas chromatography (GC), and liquid chromatography-mass spectrometry (LC-MS), which showed the presence of long-chain aliphatic fatty acid like eicosanoic acid with formation of oct-1-en-3-ol compounds attached.  相似文献   
5.
Adaptive changes in the levels of carbohydrate metabolites, glucose, glycogen and lactic acid, were studied in a freshwater edible fish, Sarotherodon mossambicus exposed to a carbamate fungicide, ziram. Based on the results obtained, it was concluded that the fish showed (i) adaptive utilization of stored glycogen, particularly in liver tissue; (ii) adaptive accumulation of glycogen in muscle and heart tissues, probably by glyconeogenesis and (iii) adaptive mechanism of operation of ‘diving syndrome’, to meet the stress of the pollutant under sub-lethal exposure. © 1998 SCI.  相似文献   
6.
The present study evaluated the effects of cryoprotectants, semen diluents and thawing temperature during Ghagus chicken semen cryopreservation. Four different experiments were conducted; Experiment 1—semen was cryopreserved using 6% dimethylacetamide (DMA) and 2% dimethylsulphoxide (DMSO) in Sasaki diluent (SD) and Lake and Ravie diluent (LR), Experiment 2 and 3—semen was cryopreserved using 8% ethylene glycol (EG) in SD, LRD and Red Fowl Extender (RFE), Experiment 4—semen was cryopreserved using 6% dimethylformamide (DMF) in SD, LR and Beltsville poultry semen extender (BPSE). Semen was cryopreserved in 0.5 ml French straws. Thawing was done at 5°C for 100 s in ice water in Experiments 1, 2 and 4, whereas in Experiment 3 thawing was done at 37°C for 30 s. The post-thaw sperm motility, viable sperm and acrosome-intact sperm were significantly (p < .05) lower in cryopreserved samples in all the experiments. No fertile eggs were obtained from cryopreserved samples in Experiments 1 and 2, except for 8% EG RFE treatment where the fertility was 0.83%. In Experiments 3 and 4, highest fertility was obtained in LR treatment 48.12 and 30.89%, respectively. In conclusion, using cryoprotectant EG (8%) and thawing at 37°C for 30 s, and DMF(6%) resulted in acceptable level of fertility in Ghagus chicken. Though the diluents influenced post-thaw in vitro semen parameters, the fertility was not affected. In addition, results indicated that thawing temperature may be a critical stage in the cryopreservation protocol.  相似文献   
7.
This study reports the results on induced meiotic diploid gynogenesis and female homogametic nature in the Indian catfish, Heteropneustes fossilis. The eggs of H. fossilis were inseminated with conspecific sperm. The sperm suspension was diluted to 1 × 107 sperm mL−1 in Hanks balanced salt solution. Sperm were irradiated under UV light, with the exposure time ranging from 15 to 360 s (7500 ergs mm−2 for 60 s). The genetic inactivation of paternal chromosomes was confirmed by chromosome counting from the larval cells and the larvae also had a characteristic haploid syndrome. A typical ‘Hertwig effect’ in the yield of hatched larvae was observed with doses of UV exposure >75 s (9375 ergs mm2). Larvae resulting from sperm UV irradiated above 120 s (15 000 ergs mm2) were 100% haploids. Application of heat shock to the activated eggs was effective in suppressing the release of the second polar body (meiotic gynogenesis) and resulted in diploid gynogenetic larvae morphologically identical to those of the control. The best yield of diploid gynogens (49.3% with respect to the control) was found to be at 6 min after egg activation and the heat shock at 41 °C for a 1-min duration, at an ambient water temperature of 27 °C. A total of 113 diploid gynogenetic fry from seven different female fish were reared and subjected to sexing. All gynogenetic fish were female in contrast to the control, which had a mean sex ratio of 56.7% females (which was not significantly different from 50% female). From these results, the sex determination mechanism in H. fossilis was presumed to be female homogamety.  相似文献   
8.
9.
1. The effects of Aspergillus oryzae- and Bacillus subtilis-based direct-fed microbials (DFM) were investigated on the performance, ileal nutrient transport and intestinal integrity of broiler chickens, raised under experimental conditions, with increased intestinal microbial challenge.

2. The first study was a 3 × 2 factorial experiment, with 3 dietary treatments (control (CON), CON + DFM and CON + antibiotic growth promoter) with and without challenge. Chicks were fed experimental diets from 1 to 28 d, while the challenge was provided by vaccinating with 10 times the normal dose of commercial coccidial vaccine on d 9. In a second experiment, two groups of 1 d-old broilers, housed on built-up litter (uncleaned from two previous flocks), were fed the same CON and CON + DFM diets from 1 to 21 d.

3. The challenge in the first experiment reduced performance, but no differences were observed among dietary treatments from 8 to 28 d. The challenge reduced the ileal epithelial flux for D-glucose, L-lysine, DL-methionine and phosphorus on d 21. Epithelial flux for D-glucose, L-lysine and DL-methionine were increased by DFM. Ileal trans-epithelial electrical resistance (TER) was increased in challenged broilers fed DFM, although this was not observed in unchallenged birds as indicated by a significant interaction.

4. Ileal mucin mRNA expression and colon TER were increased, and colon endotoxin permeability was reduced by DFM on d 21 in the second experiment.

5. It was concluded that the addition of DFM in the diet improved the intestinal integrity of broiler chickens raised under experimental conditions designed to provide increased intestinal microbial challenge.  相似文献   

10.
BACKGROUND: RNA interference (RNAi) is commonly used in insect functional genomics studies and usually involves direct injection of double‐stranded RNA (dsRNA). Only a few studies have involved exposure to dsRNAs through feeding. For western corn rootworm (Diabrotica virgifera virgifera) larvae, ingestion of dsRNA designed from the housekeeping gene, vacuolar ATPase (vATPase) triggers RNAi causing growth inhibition and mortality; however, the effect of dsRNA feeding on adults has not been examined. In this research, WCR adults were fed with vATPase‐dsRNA‐treated artificial diet containing a cucurbitacin bait, which is a proven feeding stimulant for chrysomelid beetles of the subtribe Diabroticina to which rootworms belong. RESULTS: Real‐time PCR confirmed suppression of vATPase expression and western blot analysis indicated reduced signal of a protein that cross‐reacted with a vATPase polyclonal antiserum in WCR adults exposed to artificial diet treated with dsRNA and cucurbitacin bait. Continuous feeding on cucurbitacin and dsRNA‐treated artificial diet resulted in more than 95% adult mortality within 2 weeks while mortality in control treatments never exceeded 20%. CONCLUSIONS: This research clearly demonstrates the effect of RNAi on WCR adults that have been exposed to dsRNA by feeding and establishes a tool to screen dsRNAs of potential target genes in adults. This technique may serve as an alternative to target screening of larvae which are difficult to maintain on artificial diets. Copyright © 2011 Society of Chemical Industry  相似文献   
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