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441.
Barry Mc Inerney Gerard Corkery Gashaw Ayalew Shane Ward Kevin Mc Donnell 《Computers and Electronics in Agriculture》2010,73(2):112-117
A preliminary study on the potential application of electronic tracking in poultry in vivo has been conducted. The experimental procedure for this study was based on previous in vitro findings (Fröschle et al., 2009) as part of the same research programme. The study consisted of two phases whereby an initial experiment using inkjet printing of 10 × 10 DataMatrix barcodes onto the beaks of broiler chickens in a live commercial setting has been carried out. Results demonstrated very poor percentage of readability after a short period of time. Barcodes deteriorated very rapidly and this was attributed to the physical effects on the barcodes of the actions of the chickens in a commercial environment, together with the inability of the ink to bond to the hard keratinous surface of the beak. In a subsequent part of the study, a number of commercially available ink types were screened, using a predetermined abrasion testing procedure, for their ability to bond to the beak and provide a readable barcode on the beaks following some predetermined graduated physical abrasion. 相似文献
442.
Halliwell B 《Biointerphases》2010,5(3):FA15-FA18
443.
Summary Decay columns resulting from naturally infected pruning wounds in 5‐ to 8‐year‐old plantation‐grown Eucalyptus nitens in Tasmania are interfaced by a reaction zone in the sapwood. The reaction zone is blue‐purple in colour and occasionally associated with a white zone at the reaction zone/healthy sapwood interface. A log incubation experiment has shown that the reaction zone is particularly durable against decay. The reaction zone is significantly drier than healthy sapwood, with lower levels of potassium, and a lower pH than both sapwood and heartwood. The increased total phenols levels and abundant tyloses in the reaction zone may be particularly important in defence. 相似文献
444.
Michael J. Malick James P. Losee Gary Marston Mickey Agha Barry A. Berejikian Brian R. Beckman Matthew Cooper 《Fish and Fisheries》2023,24(3):454-465
Fecundity is an important demographic parameter that contributes to the productivity of anadromous fish stock dynamics. Yet, studies on fecundity patterns in Pacific salmon (Oncorhynchus spp.) often only include a few years of data, limiting our ability to understand spatio-temporal trends. Here, we used data on 43 hatchery Chinook salmon (O. tshawytscha, Salmonidae) populations in Washington State to evaluate whether average fecundity changed over the past three decades. We then used data from a subset of stocks (18) to evaluate the relationship between fecundity and body length. Our results revealed significant changes in fecundity across the 25-year study period with most stocks showing declines in fecundity over the past decade. Results further showed that Chinook salmon have decreased in length over this same period and that annual variation in mean length explains a majority (62%) of annual variation in mean fecundity. Specifically, we estimated that a 1-mm reduction in length results in 7.8 fewer eggs (95% CI = 6.6–8.9). Given that the majority of Pacific Northwest Chinook salmon in the environment and harvested in fisheries originate from hatchery releases and that nearby hatchery and wild populations generally have similar ocean distributions, these results likely reflect patterns for many populations not included. Combined, our results highlight the need to consider changes in body size and egg production when assessing the dynamics of anadromous fish populations and designing management or conservation plans, particularly for depressed populations. 相似文献
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Graeme Jones Colin A. M. Campbell Barry J. Pye Sangita P. Maniar Alan Mudd 《Pest management science》1996,47(2):165-169
Colupulone, the main component of the beta-acid fraction of hop extracts, was shown to repel the two-spotted spider mite Tetranychus urticae Koch from the surface of plant leaves. The total beta-acid fraction was found more effective in repelling the mites and reducing the number of eggs laid than colupulone at equivalent concentrations, suggesting that other components of the extract have repellent and oviposition-deterring effects. 相似文献
450.
The status of marine biodiversity in the Eastern Central Atlantic (West and Central Africa)
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Beth A. Polidoro Gina M. Ralph Kyle Strongin Michael Harvey Kent E. Carpenter Rachel Arnold Jack R. Buchanan Khairdine Mohamed Abdallahi Camara Bruce B. Collette Mia T. Comeros‐Raynal Godefroy De Bruyne Ofer Gon Antony S. Harold Heather Harwell Percival A. Hulley Tomio Iwamoto Steen W. Knudsen Jean de Dieu Lewembe Christi Linardich Kenyon C. Lindeman Vanda Monteiro Thomas Munroe Francis K.E. Nunoo Caroline M. Pollock Stuart Poss Barry Russell Catherine Sayer Aboubacar Sidibe William Smith‐Vaniz Emilie Stump Mor Sylla Luis Tito De Morais Jean‐Christophe Vié Akanbi Williams 《水产资源保护:海洋与淡水生态系统》2017,27(5):1021-1034
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