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21.
Two methyl anthranilate formulations, ReJex‐iT® TP‐40 and AG‐36, were tested as bird‐repelling agents for animal feed and vegetable sprouts, respectively. Feral pigeons (Columba livia) and house sparrows (Passer domesticus) are important pests of animal husbandry and field crops in Israel. In each 4‐day experiment, four birds were held together in an aviary, and were offered four trays or dishes with animal feed or cauliflower sprouts in four corners of the cage. The trays and dishes were transposed daily in a Latin square sequence. Pigeons consumed significantly more untreated feed than treated feed. When no alternative untreated food was offered, there was no significant repellency. Treatment of animal feed with TP‐40 to give 2.0 ml methyl anthranilate kg?1 or less had no repellent effect on sparrows. Concentrations of 4.0 ml kg?1 or more repelled the sparrows significantly. When no untreated feed was presented, pigeons and sparrows preferred the lowest concentration of methyl anthranilate presented. When AG‐36 was tested on vegetable sprouts, the sparrows tended significantly to avoid the highest concentration used—14.5 ml methyl anthranilate litre?1 spray. The inter‐specific differences between the birds indicate that the efficacy of methyl anthranilate formulations as a repellent has to be specified for every species. This study did not determine (1) the possibility of developing habituation, (2) the behaviour of birds under natural conditions in the field, or (3) the influence of the feeding behaviour of a sympatric bird species on the repellency of methyl anthranilate to other species. © 2001 Society of Chemical Industry  相似文献   
22.
A corneo-conjunctival dermoid is reported in a blue-fronted Amazon parrot ( Amazona aestiva ). After laminar keratectomy, histology showed the epidermis with feather follicles and dermal connective tissue with lymph follicles and sebaceous glands.  相似文献   
23.
The impacts of elevated CO2 and soil water on the population dynamics, adult fecundity and nymphal period of the bird cherry-oat aphidRhopalsiphum padi (Linnaeus) were evaluated in three experiments: (i)Combined effects of CO 2 and soil water on aphid populations. Spring wheat was grown in pots at three CO2 concentrations (350, 550 and 700 ppm) and three soil water levels (40%, 60% and 80% of field water capacity, FWC) in field open-top chambers (OTC) and infested with the bird cherry-oat aphid. Aphid population dynamics were recorded throughout the growing season; at the same time, adult fecundity and duration of the nymphal period were recorded. Chemical composition of spring wheat leaves was also analyzed. (ii)Indirect effects of CO 2 concentrations and soil water on aphid adult fecundity and nymphal period. The experiment was conducted with the leaf discs method in the laboratory. Aphids were reared on leaf discs excised from the treated wheat in OTC with different CO2 and soil water levels. (iii)Direct effects of CO 2 concentrations on aphid adult fecundity and nymphal period. Aphids were reared on leaf discs excised from the wheat grown under natural conditions. The experiment was conducted with the leaf disc method in OTC with the three CO2 concentrations. It was found that the direct effect of CO2 concentration on aphid population parameters was minor. CO2 and soil water affected aphid population indirectly through their effects on wheat characteristics. The aphid population under 550 ppm CO2 was far larger than the one under 350 ppm CO2, whereas the population under 700 ppm CO2 was slightly higher than that under 550 ppm CO2. The largest aphid population was obtained with the 60% soil water treatment, regardless of CO2 treatment. The effects of CO2 concentration on aphid population were, however, not significantly correlated with soil water level. Adult fecundity increased with CO2 concentration, the highest fecundity being achieved under 60% FWC treatments. The nymphal period was not affected by CO2 concentration. The shortest period occurred under 60% FWC. Atmospheric CO2 and soil water had significant effects on the chemical composition of the wheat leaves. Aphid population size was positively correlated with leaf water content, concentrations of soluble proteins, soluble carbohydrates and starch, and negatively correlated with DIMBOA and tannins concentrations. http://www.phytoparasitica.org posting Oct. 20, 2003.  相似文献   
24.
Topical vecuronium bromide (Norcuron) and combinations with atropine and phenylephrine, were evaluated as mydriatics in juvenile double-crested cormorants (Phalacrocorax auritus). Nine cormorants were treated with each of four protocols: 1% atropine; 4 mg/mL vecuronium bromide (total 0.16 mg/eye); atropine with vecuronium; and atropine, 2.5% phenylephrine, followed by vecuronium. Drugs were applied topically at 15-min intervals (0.01 mL/drop). Pupil diameter was measured manually every 15 min with a pupil gauge calibrated to the nearest 0.5 mm. No effect was observed with atropine alone. Average +/- SD peak pupil diameter for vecuronium, atropine/vecuronium, and atropine/phenylephrine/vecuronium were 5.4 +/- 1.1 mm, 5.7 +/- 0.8 mm and 6.2 +/- 0.4 mm, respectively; and duration of peak diameters were 38 +/- 28 min, 79 +/- 71 min and 103 +/- 58 min, respectively. The combined atropine, phenylephrine and vecuronium provided the most consistent dilation with larger average pupil size and longer average duration. No side-effects from vecuronium were observed in these birds.  相似文献   
25.
观鸟是一项陶冶身心、消除疲劳、接近大自然、科学性很强的活动。扎龙国家级自然保护区内,鸟类资源丰富,是进行观鸟旅游和科普、科研的重要基地,本文主要构建了鸟类观赏性评估体系,并对保护区的鸟类进行了观赏性评估;通过问卷调查分析了观鸟者对自然保护区和鸟类的认知度、喜爱度和观鸟的期望等等;并为保护区更好地开展观鸟旅游和科研、科普活动提出管理建议。  相似文献   
26.
采用样线法及样点法相结合的方法,对湖北神农架大九湖国家湿地公园鸟类进行了近5年的观察研究。共记录到鸟类16目44科96属136种,其中,雀形目83种,非雀形目53种;水鸟28种,占湿地公园鸟类种数的20%;东洋种53种(39%)、古北种38种(27.9%)、广布种45种(33.1%);留鸟78种(57.4%)、夏候鸟38种(27.9%)、冬候鸟15种(11%)、旅鸟5种(3.7%)。大九湖国家湿地公园共有国家和湖北省重点保护鸟类40种,其中国家Ⅰ级保护鸟类3种,国家Ⅱ级保护鸟类11种;有湖北省重点保护鸟类26种。提出了大九湖国家湿地公园鸟类保护对策,为湿地公园鸟类的保护提供科学依据。  相似文献   
27.
河北省承德避暑山庄的鸟类   总被引:1,自引:0,他引:1  
2001~2003年,对河北省承德市避暑山庄的鸟类物种组成、区系型、居留期、区域分布、相对数量、珍稀种类等进行了调查。共记录到鸟类58种,隶属于13目33科58种,其中古北种31种,东洋种9种,广布种18种;夏候鸟24种,冬候鸟3种,旅鸟13种留鸟18种;国家Ⅱ级保护鸟类6种,河北省重点保护鸟类22种;从生境分布上看,平原区和山区鸟类资源最为丰富。避暑山庄应成为鸟类保护的重点地区。  相似文献   
28.
2022年7月至2023年2月对山东省聊城市3处城市竹林景观进行鸟类群落调查,共记录到鸟类15种,优势种为白头鹎(Pycnonotus sinensis)、棕头鸦雀(Paradoxornis webbianus)、树麻雀(Passer montanus)、银喉长尾山雀(Aegithalos caudatus)等小型鸟类。研究表明,适度发展混交林有利于丰富城市景观的生态多样性和物种多样性。  相似文献   
29.
The effects of adding the nonlethal bird repellent methyl anthranilate (MA), at levels of 100 and 1000 mg kg?1, to fish feed on the bioaccumulation and growth of juvenile (10 g) hybrid striped bass (Morone chrysops×M. saxatilis) and juvenile (1 g) African cichlid fish Aulonocara jacobfreibergi were investigated under laboratory conditions. The bird repellent did not have any effect on the fish growth or survival over a period of 6 weeks. MA residues at low levels of 11.2±2.6 μg g?1 were found in lipophilic tissues (liver) of MA‐fed fish. Control fish, which had no MA added to their diet, had a much lower level of 0.6±0.3 μg g?1 MA in their liver. Fish muscle was found to contain negligible MA residues, while the outer body surface mucus did not contain any MA. Following a 6‐week depuration period, during which the previously MA‐fed hybrid striped bass were fed a feed to which no MA was added, the levels of MA residues detected were reduced by one order of magnitude.  相似文献   
30.
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