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The efficacy of an ivermectin jetting fluid against the sheep body louse, Bovicola (Damalinia) ovis, in long-woolled sheep was investigated in three field trials. In all trials, louse populations in hand-jetted sheep were reduced to nondetectable numbers within 2 weeks of treatment. Bv comparison, shorn and unshorn control sheep maintained detectable infestations for the duration of the trials. 相似文献
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Eugenia Fezza Joe M. Roberts Toby J. A. Bruce Lael E. Walsh Michael T. Gaffney Tom W. Pope 《Pest management science》2023,79(11):4635-4643
BACKGROUND
Monitoring is an integral component of integrated pest management (IPM) programmes used to inform crop management decisions. Vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae), continues to cause economically significant losses in horticultural crops due to an inability to reliably detect the presence of this species before crop damage occurs. To improve vine weevil monitoring we investigated the behavioural responses of adult vine weevils to visual (monitoring tool shade/colour, height and diameter as well as the effect of monitoring tool and plant density) and olfactory (host plant and conspecifics) cues under glasshouse conditions.RESULTS
Monitoring tool shade, height and diameter all influenced monitoring tool efficacy, with individuals exhibiting a preference for black, tall and wide monitoring tools. The total number of individuals recorded in monitoring tools increased with monitoring tool density. By contrast, plant density did not influence the number of individuals recorded in monitoring tools. Yew-baited monitoring tools retained a larger number of individuals compared to unbaited ones. Similarly, more vine weevils were recorded in monitoring tools baited with yew and conspecifics than in unbaited monitoring tools or those baited with only yew. Baiting monitoring tools with conspecifics alone did not enhance the number of vine weevils recorded in monitoring tools.CONCLUSIONS
Our study confirms that visual and olfactory cues influence vine weevil behaviour. This provides information on key factors that influence vine weevil monitoring tool efficacy and can be used to inform the development of a new monitoring tool for this pest. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献4.
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Nimesha Fernando Joe Panozzo Michael Tausz Robert M. Norton Glenn J. Fitzgerald Samuel Myers Cassandra Walker James Stangoulis Saman Seneweera 《Journal of Cereal Science》2012
We investigated wheat (Triticum aestivum) grain quality under Free Air CO2 Enrichment (FACE) of 550 ± 10% CO2 μmol mol−1. In each of two full growing seasons (2008 and 2009), two times of sowing were compared, with late sowing designed to mimic high temperature during grain filling. Grain samples were subjected to a range of physical, nutritional and rheological quality assessments. Elevated CO2 increased thousand grain weight (8%) and grain diameter (5%). Flour protein concentration was reduced by 11% at e[CO2], with the highest reduction being observed at the late time of sowing in 2009, (15%). Most of the grain mineral concentrations decreased under e[CO2] - Ca (11%), Mg (7%), P (11%) and S (7%), Fe (10%), Zn (17%), Na (19%), while total uptake of these nutrients per unit ground area increased. Rheological properties of the flour were altered by e[CO2] and bread volume reduced by 7%. Phytate concentration in grains tended to decrease (17%) at e[CO2] while grain fructan concentration remained unchanged. The data suggest that rising atmospheric [CO2] will reduce the nutritional and rheological quality of wheat grain, but at high temperature, e[CO2] effects may be moderated. Reduced phytate concentrations at e[CO2] may improve bioavailability of Fe and Zn in wheat grain. 相似文献
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Thomas E. Schwedler Joe R. Tomasso John A. Collier 《Journal of the World Aquaculture Society》1989,20(3):158-161
Production characteristics of channel catfish (Ictalurus punctatus) reared in cages and open ponds were compared. Fish reared in open ponds had significantly better growth and food conversion ratios than fish reared in cages. Cages and open ponds stocked with fish which were closely graded in size produced fish with less size variability at harvest compared to ponds and cages stocked with nongraded and coarsely graded fish. The decrease in size variability at harvest was reflected in a greater proportion of marketable fish. 相似文献
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Assessment of corneal thickness,intraocular pressure,optical corneal diameter,and axial globe dimensions in Miniature Horses 总被引:1,自引:0,他引:1
OBJECTIVE: To determine corneal thickness, intraocular pressure (IOP), and horizontal and vertical corneal diameter (HCD and VCD) and to obtain axial measurements of the anterior chamber depth (ACD), crystalline lens thickness (CLT), vitreous chamber depth (VtCD), and axial globe length (AGL) in eyes of Miniature Horses. ANIMALS: 41 healthy Miniature Horses. PROCEDURE: Ocular component measurements were obtained via ultrasonic pachymetry, applanation tonometry, ultrasound, and by use of a Jameson caliper. RESULTS: Mean IOP and corneal thickness for all eyes were 26.0 mm Hg and 785.6 microm, respectively. There was no correlation of age with IOP or corneal thickness and no difference in these variables between right and left eyes or between females and males. Mean HCD andVCD were 25.8 and 19.4 mm, respectively; although there were no differences between sexes or between right and left eyes, there was positive correlation of optical corneal diameters with increasing age. Mean ACD, CLT, VtCD, and AGL were smaller in Miniature Horses (5.6, 10.0, 18.1, and 33.7 mm, respectively), compared with values for full-sized horses; there was no difference in these variables between sexes or between right and left eyes in Miniature Horses, but they were correlated with increasing age. CONCLUSIONS AND CLINICAL RELEVANCE: In Miniature Horses, corneal thickness and IOP are similar to values reported for full-sized horses and do not increase with advancing age. Vertical corneal diameter, HCD, and AGL increase until 5, 7, and 2 years of age, respectively. 相似文献