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Stable flies are one of the most important arthropod pests of livestock that reduce cattle weight gain and milk production leading to annual economic losses in excess of $2 billion to the US cattle industry. The host‐seeking behavior is primarily mediated by associated odors from stable fly larval development environments and host animals. The present paper reports the development and evaluation of attractant‐impregnated adhesive tapes to reduce stable fly attacks on cattle. Laboratory bioassays showed that only m‐cresol impregnated adhesive tapes caught significantly more stable flies (16 ± 1) than the control tape without attractant added (7 ± 1), with a 77% fly recapture rate. Attractant‐impregnated adhesive tapes deployed in cattle feedlots showed significant impacts in reducing fly population, with a total of one million stable flies captured over a period of three weeks (mean catches from 57 596 to 102 088 stable flies per trap per week). It further relieved cattle stress with a significant reduction of biting fly avoidance behavior, (6 ± 0.4 cows observed with tail wagging in control vs. 3 ± 0.4 from the trap‐deployed). The efficacy of the developed tapes lasted up to 1‐week longevity, although 70% of m‐cresol was released starting from the second day. The m‐cresol impregnated adhesive tape provided an 80% reduction in cattle stress due to stable fly attack. This is the first report of a technology developed by integrating an attractant compound into an adhesive material on a plastic film with demonstrated effectiveness in trapping biting flies that attack livestock animals. [ABSTRACT FROM AUTHOR]

BACKGROUND: Stable flies are one of the most detrimental arthropod pests to livestock. With changing climates and agronomic practices, they expand their roles as pests and disease vectors as well. Their painful bites reduce livestock productivity, annoy companion animals, and interfere with human recreational activities. Current management technologies are unable to effectively control stable flies. The present study reports new results concerning the contact, spatial repellency, and toxicity of a bio‐based product, coconut fatty acid and their methyl ester derivatives of free fatty acids of C8:0, C10:0 and C12:0 to stable flies. RESULTS: Three medium chain fatty acid methyl esters (C8:0, C10:0 and C12:0) showed strong antifeedant activity against stable flies and their strengths were dose‐dependent. Only the C8:0 acid, C8:0‐ and C10:0 methyl esters elicited significant antennal responses. Laboratory single cage olfactometer bioassays revealed that coconut fatty acid and C8:0 methyl ester displayed active spatial repellency. All three methyl esters showed strong toxicity against stable flies. CONCLUSION: Antifeedant activity is the main method through which coconut fatty acid deters stable fly blood‐feeding. The C8:0, C10:0 and C12:0 methyl esters act not only as strong antifeedants, but also possess strong toxicity against stable fly adults. Limited spatial repellency was observed from coconut fatty acid and C8:0 methyl ester. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Stable flies are considered to be one of the major blood-feeding pests in the US livestock industry, causing losses running into billions of dollars annually. Adult stable flies are highly attracted to Alsynite traps; however, Alsynite is becoming increasingly difficult to obtain and is expensive. RESULTS Here, we report on the development of a less expensive and more efficacious trap based upon a white panel with the option to add visual and olfactory stimuli for enhanced stable fly trapping. White panel traps caught twice as many stable flies than Alsynite traps. Baiting the traps with synthetic manure volatiles increased catches 2-3-fold. Electroretinographic recordings of stable flies showed strong peaks of visual sensitivities occurring at 330-360 nm, 460-525 nm and 605-635 nm. A laboratory study indicated that young stable flies are more responsive to white, whereas gravid females prefer blue; in the field, white traps caught more stable flies than patterned or blue-black traps. CONCLUSION Stable fly control can be enhanced by developing more efficient trapping systems with added visual and olfactory stimuli. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

BACKGROUND Horn flies are among the most important biting fly pests of cattle in the United States. Horn fly management is largely dependent upon pesticides, which ultimately leads to the rapid development of insecticide resistance. Alternative control strategies, including repellents, have shown promising results in reducing fly biting. In the present study, we examined the efficacy and longevity of recently identified natural product repellents against horn flies. RESULTS Catnip oil, geraniol and C8910 acids reduced horn fly feeding in a laboratory bioassay and also exhibited spatial repellency in the olfactometer. Residual activity was observed for up to 3 days in laboratory assays; however, 24 h of residual effectiveness was observed from the two repellents when applied on cattle in the field. The limited residual effectiveness was correlated with the high volatility of the major active repellent compounds. CONCLUSION All three natural product repellents effectively repel biting horn flies, exhibiting both feeding deterrence and spatial repellency. They may be used for developing an effective push-pull strategy with a slow release matrix that can prolong their effectiveness for horn fly management. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was used to characterize mitochondrial DNA (mtDNA) variation in screw-worms, Cochliomyia hominivorax, and secondary screwworm, C.macellaria, from the Caribbean, North America and South America. Four amplicons, totaling 7.1 kb, were analysed with sixteen restriction enzymes. A total of 133 restriction sites was observed in the two species, 104 in C.hominivorax, of which nineteen were variable, and ninety-five in C.macellaria, none of which was variable. Fourteen mtDNA haplotypes were observed among eighteen C.hominivorax examined. Mean divergence between C.hominivorax haplotypes (d) was 0.0064 substitutions per base-pair and genotypic diversity (G) was 0.97. Mean divergence between C.hominivorax and C.macellaria was 0.0824. Cochliomyia hominivorax haplotypes could be divided into three assemblages representing North America, South America and Jamaica, based on UPGMA clustering with d values. The assemblages did not exhibit complete geographic fidelity. These data were discordant with previously published allozyme data indicating little differentiation between screwworm populations. A scenario invoking historically isolated populations coming into contact with the introduction and movement of European livestock is proposed to explain the observed population structure of screwworm. [ABSTRACT FROM AUTHOR]

. Restriction fragment length polymorphisms in polymerase chain reaction amplified fragments (PCR-RFLP) of mitochondrial DNA were used to differentiate species of New World screwworms (Diptera: Calliphoridae). Twenty-seven restriction enzymes were screened on five regions of mtDNA. Eleven restriction fragment length patterns differentiated New World screwworm, Cochliomyia hominivorax (Coquerel), from secondary screwworm, Cochliomyia macellaria (R). Five restriction fragment length patterns were polymorphic in C. hominivorax while all fragment patterns were fixed in C. macellaria. Diagnostic restriction fragment length patterns were used for species diagnosis, whereas intraspecific variable patterns were used to characterize field samples and laboratory strains. The PCR-RFLP technique is flexible with regard to developmental stage of the sample and method of preservation. We were able to characterize specimens of all life stages from egg to adult including larvae preserved in alcohol and pinned adults. PCR-RFLP is rapid and inexpensive, enabling specimens to be characterized within 24 h for less than 2.50. [ABSTRACT FROM AUTHOR]

. The reproductive compatibility of New World screwworms, Cochliomyia hominivorax (Coquerel), from North Africa and a strain being mass produced for the Mexican eradication programme was examined to assess the feasibility of using flies from the Mexican screwworm mass production facility for a sterile insect technique eradication programme in North Africa. Males from the production strain mated randomly with females from North Africa and from the production strain when both were present. Neither strain of males discriminated between cuticular extracts of North African and production strain females containing a contact sex pheromone. Interstrain crosses between North African flies and production flies were fertile and produced fertile progeny. Chromosome morphology did not differ significantly between the two strains and homologue pairing was normal in hybrid meiotic and polytene nuclei. Mitochondrial DNA restriction site analyses indicated that the genetic divergence of the North African strain from Mexican and Central American strains was within the range of the diversity observed in Central American, Mexican and Caribbean populations. Test results indicate that New World screwworms from North Africa are reproductively compatible with the strain currently being mass produced in Mexico. Mating barriers should not impede the progress of an eradication programme using the sterile insect technique in North Africa with sterile screwworms from the Mexican mass production facility. [ABSTRACT FROM AUTHOR]

ABSTRACT In the development and testing of water-surface multiple-removal algorithms, it is valuable to have accurate synthetic seismograms which exhibit multiples, for which the multiple-free solution is known. A method is presented for constructing 2D and 3D solutions of the acoustic wave equation in water, by combining the solution from a primary source with other scaled solutions of secondary sources, which simulate diffractors. The computation involves function evaluation rather than numerical solution of differential equations and is consequently accurate and comparatively fast. The analytic formulae on which the method is based give insights into methods for multiple removal. Generalized reflection coefficients, defined on a horizontal plane above the diffractors, are derived and used to construct the integral equations which are the basis for many multiple-removal schemes. [ABSTRACT FROM AUTHOR]