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31.
The effects of saline-dissolved or Freund's incomplete adjuvant (FIA)-emulsified GnRHa treatment on the induction of ovulation in rainbow trout, Oncorhynchus mykiss, were examined. The FIA-emulsified GnRHa was first diluted in 0.25 ml physiological saline and then mixed with an equal volume of FIA. Fish were selected in the beginning of the spawning season and were allocated into four groups and were treated intraperitoneally with (a) 0.5 ml of emulsified GnRHa (GnRHa–FIA), (b) 0.5 ml saline-dissolved GnRHa in a single injection (GnRHa-1), (c) 0.5 ml saline-dissolved GnRHa in two injections spaced 1 d apart (GnRHa-2) and (d) 0.5 ml of saline (Control). The GnRHa dose in all hormone treatments was 25 µg kg− 1. All fish in the FIA–GnRHa and GnRHa-2 groups ovulated within 10 and 11 d after treatment, respectively. In contrast, only 75% in the Control fish and 60% of the fish in the GnRHa-1 group ovulated within 36 d after treatment. None of the treatments caused any pre- or post-spawning mortality in the broodstock. Fertilization, eyeing and hatching percentages of the produced progeny were normal in all the treatment groups and did not differ significantly among them. In conclusion, FIA-emulsified GnRHa can be effective in advancing the onset of and synchronizing the ovulation of rainbow trout within a two-week period, thus shortening the egg collection period, without affecting broodstock survival and egg quality.  相似文献   
32.
2002年1月至6月对孟加拉涝原地区两个不同的宗教部落(印度教和穆斯林教)的传统家园森林进行了探索性研究,包括印度教和穆斯林教社团对树种(乔木和灌木)的偏爱度、类似性、造林材料及来源、植树地点和间距。研究发现Mangifera indica作为乔木树种,Ocimum sanctum作为灌木树种为印度教社团最喜爱的树种;Artocarpus heterophyllus和Lawsonia inermis分别为穆斯林社团最喜爱乔木树种和灌木树种。两中不同宗教社团选择乔木数种的相同性为86.57%,灌木树种为78.48%。两个宗教部落使用种子和苗木作为造林材料最多。乔木树种的造林材料主要来自家园(39%)灌木树种主要来自自然界(40%)。表3参27。  相似文献   
33.
One myrsinol-type diterpene ester (1) isolated from Euphorbia decipiens was evaluated for analgesic activity in the acetic acid induced writhing test in mice. Different dose (5-20 mg/kg i.p.) of the compound showed significant antinociceptive activity, which was comparable to standard analgesic drugs, aspirin and ibuprofen (100 mg/kg i.p.).  相似文献   
34.
Antimicrobial and cytotoxic constituents from the seeds of Annona squamosa   总被引:1,自引:0,他引:1  
Annotemoyin-1, Annotemoyin-2, squamocin and cholesteryl glucopyranoside were isolated from the seeds of Annona squamosa. These compounds and plant extracts showed remarkable antimicrobial and cytotoxic activities.  相似文献   
35.
This paper explores the influence over time of past policies on people’s attitudes towards the use of forestland in Bangladesh. The discourses of the attitudes of people were captured from the observed social tradition towards forest resources. Forests were reserved systematically and solely through the Forest Department. The conservation processes were not participatory, and rights and tenure were strictly controlled. People were socially excluded and alienated from the forest, and the socio-political factors stimulated negative attitudes among people. Forests were considered to be government property, and therefore managing forests was the responsibility of the government. People only used forest resources to meet their own requirements, either with formal permission or illegally. This situation continued even after the independence of Bangladesh in 1971. As a result, the forests of Bangladesh have been degraded heavily in recent decades.  相似文献   
36.
Journal of Pest Science - Conflicting views regarding synthetic pesticides include the successful use as pest management tools for agriculture and forestry on one hand and the threats to components...  相似文献   
37.
38.
BACKGROUND: The present study describes the quantitative changes in herbicide use during the specific observation periods in the Wheat Self-sufficiency Project in Iran from 1994 to 2004 and the associated changes in herbicide risk, area and yield in this context. A risk index, the environmental impact quotient (EIQ), was used to estimate the environmental impacts (EIs) of herbicides applied to wheat agroecosystems. RESULTS: The results suggest that, during this period, the overall risk posed by the herbicides applied to wheat agroecosystems increased substantially, as evidenced by a 71% increase in herbicide usage (weight of pesticide applied) and a 62.2% increase in EI rating, in spite of an 8.2% decrease in overall EIQ rating and an 89.2% decrease in mean application rate. Furthermore, a 0.57% increase in the area and a 23.6% and 22.7% increase in irrigated and rainfed yields, respectively, were observed. The results also indicate that the EIQ(FUR) of two herbicides, dichlorprop-P/mecoprop-P/MCPA and difenzoquat, is much higher than that of other herbicides, and they could be qualified as high-risk herbicides. CONCLUSION: As a whole, an increase in herbicide usage (weight of pesticide applied) was an important factor on herbicide environmental impact boost. However, this increase has not led to a similar increase in wheat yield, which could be attributed in part to the negative impact of high herbicide consumption in wheat fields and subsequent threat to the long-term sustainability of these agroecosystems.  相似文献   
39.
European Journal of Forest Research - Many studies have been conducted on the effects of changes in plant diversity and species composition on ecosystem functioning and plant productivity due to...  相似文献   
40.

The aim of the present study was to determine the chemical composition of Sambucus ebulus and Actinidia deliciosa ethanolic extracts as well as their in vitro antifungal activity on the mycelial growth of the water mold, Saprolegnia parasitica. The preliminary minimum inhibition concentration (MIC) and minimum lethal concentration (MLC) were determined by the HeMP method and finally, concentrations of each extract ranging from 1 to 10% were prepared by an agar dilution method to assess the in vitro antifungal activity, quantitatively. Both herbal extracts inhibited growth of Saprolegnia hyphae in vitro. Complete in vitro growth inhibition was found at a concentration of ≥5% for S. ebulus, whereas it was not observed even at 10% concentration of A. deliciosa. Based on gas chromatography coupled with mass spectrometry (GC/MS) analysis, the main constituents of S. ebulus include monophthalate (66.17%), fatty acids (26.47%), phytol (4.25%), and acetic acid (2.11%). Using colorimetric assays, A. deliciosa contained phenolic contents at 162 mg gallic acid (GAE)/g DW and flavonoid contents at 2.31 mg quercetin (QE)/g DW. In conclusion, the results of this study indicated that S. ebulus and A. deliciosa showed some antifungal activities against S. parasitica with formerly exhibiting stronger activity (p < 0.05).

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