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41.
R. Michael Erwin 《Biological conservation》1980,18(1):39-51
More than 80% of the beach-nesting seabirds (common tern, least tern, black skimmer, and herring gull) in coastal Virginia nest on natural barrier island beaches, while in New Jersey the vast majority nest on dredge deposition material or natural marsh islands. This contrast probably results from the differences in human disturbance in the two regions. Although 75% of all oceanfront in New Jersey allows unrestricted recreation, about 85% of the Virginia beaches are ‘protected’ under the ownership of several conservation agencies. Attendant with changes in habitat utilisation in New Jersey, competitive interactions have apparently intensified with herring gulls usurping tern and laughing gull nest sites. Other implications are discussed. 相似文献
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Ding Wang Young Dal Jang Gregg K Rentfrow Michael J Azain Merlin D Lindemann 《Journal of animal science》2022,100(6)
The study aimed to assess the effects of vitamin E (VE) supplementation and fat source on fatty acid (FA) composition, VE concentrations, and antioxidant capacity in plasma and tissues of pigs fed to a heavy slaughter weight (150 kg). A total of 64 pigs (32 barrows, 32 gilts; 28.41 ± 0.83 kg) were blocked by sex and weight, and randomly assigned to one of eight dietary treatments (n = 8 per treatment) in a 4 × 2 factorial arrangement. Fat sources included corn starch (CS), 5% tallow (TW), 5% distiller’s corn oil (DCO), and 5% coconut oil (CN); VE supplementation levels were 11 and 200 ppm. Five-phase diets were formulated to meet requirement estimates of NRC (2012) and fed to pigs for each period of 25 kg from 25 to 150 kg. Increasing VE supplementation level increased C16:1 (P < 0.05) content but decreased C20:0 (P < 0.05) content in backfat and belly fat, while in liver, it increased C17:0 (P < 0.05) but decreased C18:0 (P < 0.05). Compared to the pigs fed the CS diet, the pigs fed the CN diet had greater (P < 0.05) content of total saturated FA, the pigs fed the DCO diet had greater (P < 0.05) content of total polyunsaturated FA content and iodine value, and the pigs fed the TW diet had greater (P < 0.05) content of total monounsaturated FA in backfat, belly fat, and liver. Plasma VE concentrations increased linearly (P < 0.05) with increasing length of feeding but faster (P < 0.05) in the pigs fed the CN and TW diets compared with the CS and DCO diets within the 200 ppm VE level; the pigs fed the DCO diet had the highest plasma VE concentrations (P < 0.05) from Phase 2 to Phase 5 within the 11 ppm VE level. The VE concentrations in liver and loin muscle (P < 0.05) increased with increasing dietary VE level from 11 to 200 ppm, but it was not affected by dietary fat source. There was no effect of VE supplementation and fat source on antioxidant capacity in plasma and liver except that pigs fed the DCO diet had greater liver SOD activity (P < 0.05) than the pigs fed the CN diet. In conclusion, dietary VE supplementation did not affect FA profile in backfat, belly fat, and liver consistently, while dietary FA composition with different fat sources affected much of the FA profile in backfat, belly fat, and liver. The higher level of VE supplementation increased liver and muscle VE concentrations and dietary fat sources affected plasma VE concentrations differently (P < 0.05), wherein the TW and CN diets increased the VE absorption greater than the DCO diet. 相似文献
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ABSTRACTPest management professionals in California receive more customer complaints about Argentine ants than for any other urban ant pest. Fipronil, applied as a 30 × 30 cm band around the house foundation, has become the preferred treatment used to control these ants. Unfortunately, fipronil is now showing up in urban waterways at levels that are toxic to aquatic invertebrates. Our recent studies are aimed at mitigating insecticide runoff while still controlling the ant infestations. A high priority is preventing fipronil runoff from the driveway to the street, where it can flow into drains and from there to urban waterways. In this paper, two related studies address these issues. Not treating driveways with fipronil reduced by two to three orders of magnitude its runoff when compared with earlier studies. However, not treating the driveway can reduce efficacy of treatments. Granular bifenthrin, indoxacarb, botanicals, and a thiamethoxam ant bait were tested as supplemental treatments. The gel bait showed the best result as a supplement, but only after 8 weeks. We have reduced fipronil runoff while maintaining efficacy of the ant treatments. 相似文献
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单克隆抗体检测栗疫菌dsRNA的研究初报 总被引:4,自引:0,他引:4
本文利用dsRNA特异性单克隆抗体,采用双抗体夹芯ELISA法,检测了栗疫菌中的dsRNA.结果表明,该法不仅能从栗疫菌低毒力菌株的总核酸粗提液中检测到dsRNA而不受其它核酸的干扰,而且比电泳法简便迅速,在大量筛选含dsRNA的栗疫菌低毒力菌株中具有很大的实用价值。 相似文献
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