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141.
A survey of stored product pests, their natural enemies, grain storage and pest management approaches in northern Namibia
was conducted. The survey revealed five types of crop commodities (pearl millet, sorghum, cowpea, maize, feed mixture) stored
in four types of grain stores (baskets, bag stags-flat stores, concrete bin, metal containers). No synthetic pesticides or
plastic sheeting was recorded. Wooden-ash natural pesticide is the only protectant used. Ten insect pest species were found
affiliated to the orders of Coleoptera (Attagenus fasciatus, Callosobruchus subinnotatus, Cryptolestes ferrugineus, Oryzaephilus surinamensis, Rhyzopertha dominica and Tribolium castaneum), Lepidoptera (Corcyra cephalonica, Sitotroga cerealella), Psocoptera (Liposcelis paeta) and Blattodea (Blattella germanica). Out of these, seven species were recognized as new stored-products pests for Namibia. Although listed for southern Africa
region, no storage pest-mites (Acari) and Sitophilus spp., Prostephanus sp. or Trogoderma sp. beetles were traced. We found four new species of natural enemies of storage pests recruiting from insects (Habrobracon hebetor, Cephalonomia wattersoni, Brachymeria sp.) and mites (Blattisocius tarsalis). The occurrence of natural enemies indicates a potential for pest bio-control in Namibian grain stores. 相似文献
142.
Background
Little is known about foot lesions in dairy cattle in Ireland, managed under a pasture based system with housing during the winter and grazing for the rest of the year. Ten Irish dairy herds, with a lameness prevalence ranging from 9 to 17 % were locomotion scored routinely during the 2013 grazing season. Lame cows were foot trimmed and foot lesions recorded.Findings
11.8 % and 89.6 % of cows had lesions recorded on front and hind feet respectively. No lesions were found in 6.9 % of cows. Sole haemorrhage and white line disease were the most prevalent lesions, and overall 76.8 % of lesions affecting the claw horn were diagnosed on the lateral hind claw.Conclusions
Treatment success, as measured by improved LS post treatment, was not significantly affected by the LS prior to foot trimming, the presence of lesions or the type of lesion identified. Exposure to both risk factors for lameness at housing and pasture may have resulted in the development of a combination of foot lesions typically associated with zero-grazing or all-year-round grazing management systems. 相似文献143.
Suppression of bovine viral diarrhea virus replication by small interfering RNA and short hairpin RNA-mediated RNA interference 总被引:2,自引:0,他引:2
Bovine viral diarrhea virus (BVDV) is a ubiquitous viral pathogen that affects cattle herds' worldwide causing significant economic loss. The current strategies to control BVDV infection include vaccination (modified-live or killed) and control of virus spread by enhanced biosecurity management, however, the disease remains prevalent. With the discovery of the sequence-specific method of gene silencing known as RNA interference (RNAi), a new era in antiviral therapies has begun. Here we report the efficient inhibition of BVDV replication by small interfering (siRNA) and short hairpin RNA (shRNA)-mediated gene silencing. siRNAs were generated to target the 5' non-translated (NTR) region and the regions encoding the C, NS4B and NS5A proteins of the BVDV genome. The siRNAs were first validated using an EGFP/BVDV reporter system and were then shown to suppress BVDV-induced cytopathic effects and viral titers in cell culture with surprisingly different activities compared to the reporter system. Efficient viral suppression was then achieved by bovine 7SK-expressed BVDV-specific shRNAs. Overall, our results demonstrated the use of siRNA and shRNA-mediated gene silencing to achieve efficient inhibition of the replication of this virus in cell culture. 相似文献
144.
Despite the recent success of Alabama shrimp farmers in culturing the Pacific white shrimp, Litopenaeus vannamei , in inland low-salinity waters there is large variability in growth and survival among ponds. Farmers suspect that high mortality occurs during the first weeks of culture following stocking of postlarvae (PL). In order to determine the effect of pond ionic composition on PL growth and survival, three trials were carried out at a shrimp farm. Trials 1 and 2 evaluated PL growth and survival over 21- and 28-day periods, respectively, using static water from different production ponds. Trial 3 evaluated growth and survival over 7, 14, 21 and 28 days using water from one production pond. Results suggest that initial mortality (8–10%) is attributed to the acclimation process and occurs immediately following stocking. Pond-to-pond variations in ionic profiles could be a contributing factor but are not likely the major reason for variable 'survival'. Mortalities after stocking appear to occur quickly as there were no differences in survival from 7 to 28 days post stock. Variable survival is likely due to a combination of reasons including environmental factors, but is largely due to poor handling of PL and stocking errors that produce perceived reductions in survival. 相似文献
145.
We investigated patterns of moth occurrence among habitats in two different landscapes surrounding roosts of the endangered Ozark big-eared bat (Corynorhinus townsendii ingens) from May to August 2005, and compared these data with published results on the diet of this subspecies. Landscapes were situated in the Ozark Mountains, USA, and consisted of a fragmented, agricultural landscape and a contiguous national forest. We captured 8720 moths constituting ≥314 species and 22 families. Pastures demonstrated a lower abundance and richness of moths than other habitats in the fragmented landscape (p < 0.05). Neither abundance nor richness of moths varied by habitat in the forested landscape, but we did observe variation among roost locations (p < 0.05). Abundant families of moths (n ≥ 100 specimens captured) did vary in abundance among habitats in both landscapes (p < 0.05), with poletimber stands, riparian forest and upland forest selected, and pasture, forest edge, sawtimber and sapling stands avoided by at least one family of moths. Density and richness of woody plant species were correlated with the occurrence of moths at sampling sites. We recommend maintaining habitat heterogeneity around roosts of the Ozark big-eared bat to encourage an abundance and richness of moth prey, and suggest that forested riparian corridors are important habitat elements for Ozark big-eared bats foraging in fragmented landscapes. 相似文献
146.
147.
Mayakaduwage Sonia Alamgir Md Mosley Luke Marschner Petra 《Journal of Soils and Sediments》2020,20(3):1446-1453
Journal of Soils and Sediments - Acid soils often have low P availability limiting plant growth, which is addressed by application of inorganic fertilizers and neutralizing agents. However, little... 相似文献
148.
Grayson K. Walker Valeriia Yustyniuk John Shamoun Megan E. Jacob Maria Correa Shelly L. Vaden Luke B. Borst 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(4):1322
BackgroundUrinary tract infections (UTI) caused by Escherichia coli and Enterococcus spp., which are frequently coisolated in polymicrobial UTI, cause morbidity among dogs and warrant antimicrobial therapy.ObjectivesTo evaluate clinical features of dogs with polymicrobial E. coli and Enterococcal UTI.AnimalsForty‐four client‐owned dogs with polymicrobial bacteriuria and groups of 100 client‐owned dogs with E. coli and Enterococcal monomicrobial bacteriuria.MethodsRetrospective cohort study of medical records of dogs at a university teaching hospital from 2014 to 2019. Prevalence of recurrent UTI and isolate antimicrobial resistance were determined. Clinical outcomes of dogs with recurrent UTI from groups including cost and hospital visits were compared.ResultsRecurrent UTI was more prevalent (P = .05) in dogs with polymicrobial bacteriuria (57%, 95% confidence interval [95% CI]: 42%‐70%) compared to the Enterococcal monomicrobial group (40%, 95% CI: 31%‐50%). Escherichia coli from polymicrobial bacteriuria were more frequently resistant to doxycycline (P < .01, 43%, 95% CI: 29%‐58%) and gentamicin (P = .03, 17%, 95% CI: 9%‐31%) compared to E. coli from monomicrobial bacteriuria (17% and 5%, 95% CI: 11%‐26% and 2%‐11% for doxycycline and gentamicin, respectively). Dogs with recurrent UTI from the polymicrobial UTI group had significantly (P = .05) more hospital visits (mean = 6 visits, 95% CI: 1.7‐9.8) compared to recurrent monomicrobial UTI dogs (mean = 4 and 3 visits, 95% CI: 1.0 to 4.4 and −0.7 to 7.7 for E. coli and Enterococcal monomicrobial UTI, respectively).Conclusions and Clinical Importance Escherichia coli and Enterococcus spp. polymicrobial UTI had more frequent adverse clinical outcomes for dogs. 相似文献
149.
Edith K. Y. Tang Gavin J. Partridge Lindsey D. Woolley Luke Pilmer Lee Yong Lim 《Marine drugs》2022,20(5)
Praziquantel (PZQ) provides an effective treatment against monogenean parasitic infestations in finfish. However, its use as an in-feed treatment is challenging due to palatability issues. In this study, five formulations of PZQ beads (1–4 mm) were developed using marine-based polymers, with allicin added as a flavouring agent. All formulations attained PZQ loading rates ≥74% w/w, and the beads were successfully incorporated into fish feed pellets at an active dietary inclusion level of 10 g/kg. When tested for palatability and digestibility in small yellowtail kingfish, the PZQ-loaded beads produced with alginate-chitosan, alginate-Cremophor® RH40, and agar as carriers resulted in high consumption rates of 99–100% with no digesta or evidence of beads in the gastrointestinal tract (GIT) of fish fed with diets containing either formulation. Two formulations produced using chitosan-based carriers resulted in lower consumption rates of 68–75%, with undigested and partly digested beads found in the fish GIT 3 h post feeding. The PZQ-loaded alginate-chitosan and agar beads also showed good palatability in large (≥2 kg) yellowtail kingfish infected with gill parasites and were efficacious in removing the parasites from the fish, achieving >90% reduction in mean abundance relative to control fish (p < 0.001). The two effective formulations were stable upon storage at ambient temperature for up to 18 months, showing residual drug content >90% compared with baseline levels. Overall, the palatability, efficacy and stability data collected from this study suggest that these two PZQ particulate formulations have potential applications as in-feed anti-parasitic medications for the yellowtail kingfish farming industry. 相似文献
150.
Comparison of Four Artificial Light Technologies for Indoor Aquaponic Production of Swiss Chard,Beta vulgaris,and Kale,Brassica oleracea 下载免费PDF全文
Luke P. Oliver Shawn D. Coyle Leigh A. Bright R. Charles Shultz Janelle V. Hager James H. Tidwell 《Journal of the World Aquaculture Society》2018,49(5):837-844
To date, most aquaponic research has been conducted outdoors in tropical climates or in greenhouses in subtropical climates. For more northerly latitudes, aquaponic production will require supplemental light in greenhouses or insulated buildings. Two separate 3‐wk growth trials were conducted to evaluate the effects of four different lighting technologies on the growth of Swiss chard, Beta vulgaris (Trial 1) and kale, Brassica oleracea (Trial 2) in aquaponic systems. Light technologies evaluated included fluorescent (FLO), metal halide (MH), induction (IND), and light‐emitting diode (LED). Four 1175‐L systems were used with all four light types represented in each system in a complete block design. Juvenile Nile tilapia, Oreochromis niloticus (241 g) were stocked in each system and fed a floating 32% protein diet at a rate of 60 g/m2 of plant grow space per day. In Trial 1, Swiss chard plants grown under LED lights for 3 wk achieved significantly higher (P ≤ 0.05) average individual weights (117.7 g), higher production per unit of area (3535 g/m2), and higher production per unit of energy (32.3 g/m2/kwh) than Swiss chard grown under the other three light types, which did not differ significantly (P > 0.05) from each other. In Trial 2, kale grown under LED lights achieved significantly higher (P ≤ 0.05) average individual weights (102.9 g), higher production per unit of area (2136.6 g/m), and higher production per unit of energy (381.5 g/m2/kwh) than kale grown under the other three light types, which did not differ significantly (P > 0.05). The results of the two trials are in agreement and indicate that LED lights were superior to MH, FLO, and IND lights in terms of absolute plant growth as well as growth per unit of energy consumed. 相似文献