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Jinping Zhang Feng Zhang Tara Gariepy Peter Mason Dave Gillespie Elijah Talamas Tim Haye 《Journal of pest science》2017,90(4):1127-1141
The brown marmorated stink bug, Halyomorpha halys (Stål), native to China, Japan, and Korea, has emerged as a harmful invasive pest of a variety of crops in North America and Europe. The Asian egg parasitoid Trissolcus japonicus has been identified as the most promising agent for classical biological control of invasive H. halys populations. A 4-year study evaluated the fundamental and ecological host ranges of T. japonicus as well as its phenology and impact on H. halys populations in fruit orchards in its native range in northern China. In laboratory no-choice tests, developmental suitability of eight non-target host species for T. japonicus was demonstrated by the successful production of progeny on the majority (>85%) of non-target host species tested. In field-collected, naturally laid egg masses, T. japonicus was the most abundant parasitoid associated with H. halys and Dolycoris baccarum, but was also sporadically found in Plautia crossota. Furthermore, it was regularly reared from sentinel egg masses of Menida violacea, Arma chinensis, and Carbula eoa. The only species that did not support development in the laboratory and field was Cappaea tibialis. Besides the benefit of having a high impact on H. halys populations in Northern China, the risk assessment conducted in the area of origin indicates that native Pentatomidae in North America and Europe could be negatively impacted by T. japonicus. Whether the benefits of T. japonicus outweigh the possible risks will have to be evaluated based on the outcome of additional host range studies in the two invaded regions. 相似文献
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Influence of terrestrial lipid and protein sources and activated carbon‐treated fish oil on levels of persistent organic pollutants and fatty acids in the flesh of Atlantic salmon 下载免费PDF全文
Erin N Friesen Brent J Skura Michael G Ikonomou Åage Oterhals Dave A Higgs 《Aquaculture Research》2015,46(2):358-381
Reductions in flesh contaminant concentrations were evaluated in a 36‐week feeding trial examining several dietary techniques. Atlantic salmon were fed one of seven dietary treatments for 24 weeks. These diets included a fishmeal, fish oil control diet, an industry control diet, three diets that examined a 75% replacement level of anchovy oil (AO) with flaxseed oil, canola oil and poultry fat, and two diets formulated to be low in contaminants formulated with canola oil, activated carbon‐treated anchovy oil and canola protein concentrate or soy protein concentrate. Following this initial 24‐week feeding interval, a 12‐week finishing diet was utilized to restore the levels of omega‐3 highly unsaturated fatty acids (n‐3 HUFAs). The salmon had marked reductions in their flesh concentrations of total polychlorinated biphenyls (PCBs), dioxin‐like PCBs and total toxic equivalents by the end of the grow‐out phase, but also exhibited significant depressions in their flesh concentrations of n‐3 HUFAs relative to 100AO‐fed fish. The 12‐week finishing diet period was effective in partially re‐instating omega‐3 levels to those present in the flesh lipids of fish fed 100AO while concurrently maintaining lower flesh contaminant concentrations. 相似文献
84.
Rebecca Lyn Pond Michael J. Darre Peter M. Scheifele Dave G. Browning 《Journal of Veterinary Behavior: Clinical Applications and Research》2010,5(1):7-12
Bioacoustics is the study of sound in animals and includes, but is not limited to, animal communication with associated behavior, sound production anatomy and neurophysiology, auditory capacities and auditory mechanisms, and animal welfare. The present research investigates the vocalizations of horses during stressful situations. Stress can be positive or negative. Distress is anything that affects the animal in a negative way, such as in mare and foal separation. Eustress is anything that affects the animal in a positive way, such as morning feeding time in a horse barn. The purpose of the current research is to find spectral differences in the recorded vocalizations of stalled horses that indicate both distress and eustress using the Hidden Markov Model (HMM). Greenwood Function Cepstral Coefficient values suggest that there are spectral differences between vocalizations in a distress and eustress situation. These consistent results indicate that further research to obtain and evaluate vocalizations of horses may provide a productive tool in understanding equine welfare. 相似文献
85.
OBJECTIVE: This paper examines trends in the neighbourhood food store environment (defined by the number and geographic density of food stores of each type in a neighbourhood), and in food consumption behaviour and overweight risk of 5779 men and women. DESIGN: The study used data gathered by the Stanford Heart Disease Prevention Program in four cross-sectional surveys conducted from 1981 to 1990. SETTING: Four mid-sized cities in agricultural regions of California. SUBJECTS: In total, 3154 women and 2625 men, aged 25-74 years. RESULTS: From 1981 to 1990, there were large increases in the number and density of neighbourhood stores selling sweets, pizza stores, small grocery stores and fast-food restaurants. During this period, the percentage of women and men who adopted healthy food behaviours increased but so did the percentage who adopted less healthy food behaviours. The percentage who were obese increased by 28% in women and 24% in men.ConclusionFindings point to increases in neighbourhood food stores that generally offer mostly unhealthy foods, and also to the importance of examining other food pattern changes that may have a substantial impact on obesity, such as large increases in portion sizes during the 1980s. 相似文献
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Erin Friesen Shannon K Balfry Brent J Skura Michael Ikonomou Dave A Higgs 《Aquaculture Research》2013,44(2):300-316
The objective of this study was to access the suitability of using poultry fat (PF) or blends of PF with flaxseed oil (FO) to replace 75% of the supplemental anchovy oil (AO) in the diet of juvenile sablefish (Anoplopoma fimbria), a relatively new marine species to aquaculture. Sablefish were fed one of four diets twice daily to satiation for 15 weeks. The test diets were identical in composition except for the source of supplemental lipid which was either 100% AO (100AO), or had 75% of the supplemental AO replaced with 50% FO:25% PF, 25% FO:50% PF or 75% PF. Sablefish growth parameters, whole body and fillet proximate constituent concentrations, and apparent digestibility coefficients were uninfluenced by diet treatment. There were also no adverse effects of the diet treatments on fish health, as determined from analysis of various haematological and innate immunological parameters. Terminal fillet fatty acid compositions generally reflected the dietary fatty acid compositions. Results indicated that PF or blends of PF and FO may comprise 75% of the supplemental lipid in a grower diet for sablefish and are an economic alternative to AO while still providing humans with a rich dietary source of highly unsaturated fatty acids. 相似文献
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Natalie Hicks Mark T Bulling Martin Solan Dave Raffaelli Piran CL White David M Paterson 《BMC ecology》2011,11(1):1-8