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1.
Age Ageing ; 46(1): 112-118, 2017 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-28181654

RESUMEN

Introduction: In the United Kingdom dementia is generally diagnosed by mental health services. General hospitals are managed by separate healthcare trusts and the handover of clinical information between organisations is potentially unreliable. Around 40% of older people admitted to hospital have dementia. This group have a high prevalence of psychological symptoms and delirium. If the dementia diagnosis or symptoms are not recognised, patients may suffer unnecessarily with resulting negative outcomes. Methods: To understand areas of unmet need we have described the prevalence of dementia in over 75 year olds admitted to a general hospital, the accuracy of diagnostic recording, and the prevalence of recorded psychological symptoms and delirium. To achieve this we conducted a retrospective review of 116 patients admitted to hospital with known dementia. Psychiatric and medical notes were reviewed, identifying the accuracy dementia diagnosis recording by the hospital and all episodes of documented psychological symptoms and delirium. Results: The prevalence of documented dementia in the population was estimated at 15%; 74% of dementia diagnoses were recorded in the medical notes; 10% had documented psychological symptoms (depression 4%, anxiety 3%, hallucinations 3%, delusions 4%); and 11% had documented delirium. There were no associations between the specialty providing care and the recognition of dementia or the reporting of symptoms. Discussion: This work suggests an under reporting of dementia and symptoms associated with it in the general hospital. Improving this requires closer collaboration between metal health and hospital healthcare services and training for staff on how to access diagnostic information and recognise common psychological symptoms.


Asunto(s)
Delirio/diagnóstico , Demencia/diagnóstico , Evaluación Geriátrica/métodos , Hospitales Generales , Admisión del Paciente , Anciano , Anciano de 80 o más Años , Delirio/epidemiología , Delirio/psicología , Demencia/epidemiología , Demencia/psicología , Femenino , Humanos , Comunicación Interdisciplinaria , Masculino , Registros Médicos , Grupo de Atención al Paciente , Valor Predictivo de las Pruebas , Prevalencia , Reproducibilidad de los Resultados , Estudios Retrospectivos , Reino Unido/epidemiología
2.
J Econ Entomol ; 105(6): 2207-12, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23356088

RESUMEN

Over a 7 yr period, we monitored the effect of a commercially available, amitraz impregnated anti-tick collar in controlling free-living populations of lone star ticks, Amblyomma americanum (L.) when manually fitted around necks of white-tailed deer, Odocoileus virginianus (Zimmermann). Study animals in treatment and control groups were confined in 38.8 ha game-fenced and densely vegetated treatment plots in South Texas. Tick densities during years 1 and 7 served as untreated pre- and posttreatment comparisons and treatments occurred during years 2 through 5. Reductions in tick densities in the treatment plot were compared against tick densities in a control plot having similar vegetation and numbers of untreated deer. During years of treatment, indices of control pressure ranged from 18.2 to 82.6 for nymphs and 16.9-78.7 for adults, and efficacy, expressed as percentage control during the final year of treatment, was 77.2 and 85.0%, respectively, for nymphal and adult ticks. These data show that acaricidal collar treatments provide efficacies very similar to those achieved with the existing ivermectin-medicated bait and '4-Poster' topical treatment technologies to control ticks feeding on wild white-tailed deer.


Asunto(s)
Ciervos/parasitología , Repelentes de Insectos/administración & dosificación , Ixodidae , Control de Ácaros y Garrapatas , Toluidinas/administración & dosificación , Animales , Densidad de Población
3.
J Econ Entomol ; 103(2): 211-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20429430

RESUMEN

From 1907 when the fever tick eradication campaign began until 1933, the tick eradication methods of dipping cattle in an acaricide or "pasture vacation" were enormously successful in eradicating southern cattle ticks [Rhipicephalus (Boophilus) microplus (Canestrini)], until failures began to occur in some areas of Florida. Regarding the failures in Florida, the consensus was that populations of white-tailed deer [Odocoileus virginianus (Zimmermann)] infested with southern cattle ticks were responsible. After numerous deer in several counties were killed, eradication was achieved in Florida. As in Florida, in Texas increasing numbers of failures of the pasture vacation approach to tick eradication from the 1970s to the present are known to be related to the abundance of white-tailed deer and perhaps other wild ungulate species. A sizable body of evidence confirms the hypothesis that white-tailed deer support the dispersal and maintenance of both cattle ticks [Rhipicephalus (Boophilus) annulatus (Say)] and southern cattle ticks (cattle fever ticks) within the permanent quarantine or buffer zone in South Texas along the Rio Grande, as well as in the so-called free ("cattle fever tick-free") area north and east of the buffer zone and extending to the east coast of the United States. As of August 2009, in addition to the permanent quarantine zone of approximately 2233 km2, three temporary preventative or blanket quarantines were established. Currently, only two methodologies exist to control ticks feeding on white-tailed deer: (1) a systemic treatment method involving dispersal of ivermectin-medicated corn, Zea mays L.; and (2) two topical treatment methods, '4-poster' deer treatment bait stations and '2-poster' deer treatment feeder adapters, both of which passively apply topically active acaricide to deer for the eradication of populations of cattle fever tick associated with white-tailed deer. This study presents and summarizes confirmational support for the role of white-tailed deer derived from historical accounts, circumstantial evidence from review of recent infestations, and cattle fever tick infestations on white-tailed deer that were live-captured and examined specifically for cattle fever ticks.


Asunto(s)
Ciervos , Ixodidae/fisiología , Infestaciones por Garrapatas/veterinaria , Animales , Bovinos , México/epidemiología , Texas/epidemiología , Infestaciones por Garrapatas/epidemiología
4.
J Med Entomol ; 46(6): 1299-302, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19960673

RESUMEN

Female engorgement weight, oviposition, and molting times of larvae and nymphs of Amblyomma maculatum Koch (Acari: Ixodidae) were studied at various photoperiods under constant humidity and temperature in the laboratory. Ticks were held at photoperiods of 0:24, 10:14, 12:12, or 14:10 (L:D) h from egg through unfed nymphal stage and then at either the same or a different regime from fed nymphs to adults. No significant effects were observed on oviposition, female engorgement weights, survival, or molting time to unfed nymphs. Nymphal molting times were significantly shorter at the short-day regime (10:14) during the larval stage and 12:12 during the nymphal stage compared with those held at either 14:10 during both life periods or at 0:24 during both life periods. Longer molting times also were observed in ticks held at 12:12 during the larval phase and either 10:14, 12:12, or 0:24 during the nymphal phase compared with 14:10 during both life periods or 0:24 during both life periods. Ticks held at 10:14 during the larval phase and at 0:24 or 10:14 had longer molting times compared with those at 14:10 or 0:24 during both life periods. No differences in survival to either nymphal or adult stages were observed at any regime, and at day 25 no individuals were observed to be in developmental diapause. This study demonstrates that developmental diapause does not seem to be photoperiodically induced in fed nymphal A. maculatum in the laboratory.


Asunto(s)
Ixodidae/fisiología , Fotoperiodo , Animales , Femenino , Ixodidae/crecimiento & desarrollo , Muda , Ninfa/crecimiento & desarrollo , Oviposición , Reproducción/fisiología , Factores de Tiempo
5.
Bioresour Technol ; 100(20): 4854-62, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19520567

RESUMEN

Molasses fermentation performance by both a cryotolerant and a thermophilic yeast (strain AXAZ-1) isolated from grapes in Greece was evaluated in an extremely wide temperature range (3-40 degrees C). Sequence analysis of the 5.8S internal transcribed spacer and the D1/D2 ribosomal DNA (rDNA) regions assigned isolate to Saccharomyces cerevisiae. Restriction fragment length polymorphism of the mitochondrial DNA showed that strain AXAZ-1 is genetically divergent compared to other wild strains of Greek origin or commercial yeast starters. Yeast cells growing planktonically were capable of fermentation in a wide temperature spectrum, ranging from 3 degrees C to 38 degrees C. Immobilization of yeast on brewer's spent grains (BSG) improved the thermo-tolerance of the strain and enabled fermentation at 40 degrees C. Time to complete fermentation with the immobilized yeast ranged from 20 days at 3 to 38 h at 40 degrees C. The daily ethanol productivity reached maximum (58.1 g/L) and minimum (2.5 g/L) levels at 30 and 3 degrees C, respectively. The aroma-related compounds' profiles of immobilized cells at different fermentation temperatures were evaluated by using solid phase microextraction (SPME) gas chromatography-mass spectrometry (GC-MS). Molasses fermentation resulted in a high quality fermentation product due to the low concentrations of higher and amyl alcohols at all temperatures tested. Strain AXAZ-1 is very promising for the production of ethanol from low cost raw materials, as it was capable to perform fermentations of high ethanol concentration and productivities in both low and high temperatures.


Asunto(s)
Fermentación , Melaza , Saccharomyces cerevisiae/fisiología , Temperatura , Células Inmovilizadas , ADN Mitocondrial/análisis , ADN Mitocondrial/genética , ADN Ribosómico/genética , ADN Espaciador Ribosómico/genética , Cromatografía de Gases y Espectrometría de Masas , Cinética , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/genética , Análisis de Secuencia de ADN , Microextracción en Fase Sólida , Volatilización
6.
Vet Parasitol ; 145(1-2): 156-63, 2007 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-17178440

RESUMEN

The sudden death of several cattle infested experimentally with Rhipicephalus (Boophilus) microplus led to a clinical investigation into the reasons for the unexpected mortality. Microscopic evidence for Babesia bigemina infection was found in blood smears from the affected animals and a PCR assay was designed to detect the presence of B. bigemina and Babesia bovis in all R. microplus strains received and propagated at the laboratory. The assay utilizes a nested PCR approach with the first PCR amplifying a well-conserved segment from the Babesia 18S ribosomal RNA gene followed by a nested PCR with Babesia species-specific primers and annealing temperatures enabling amplification of the 18S ribosomal RNA gene fragment specific to either B. bigemina or B. bovis. DNA from groups of 50 larvae was extracted using a rapid DNA preparation protocol, which consisted of grinding the frozen tick larvae in PCR buffer and boiling the mixture for 5min. The assay sensitivity allowed for the detection of the equivalent of a single infected tick larva. R. microplus eggs were also analyzed, but yolk protein viscosity created inconsistent results with the crush and boil DNA isolation protocol, necessitating the use of a more extensive proteinase K digestion-based DNA purification method. We detected the presence of B. bigemina in all strains of R. microplus currently reared at the laboratory and 4 of 26 strains collected from infestation outbreaks in Texas by the U.S. Cattle Fever Tick Eradication Program.


Asunto(s)
Babesia/aislamiento & purificación , Babesiosis/transmisión , Enfermedades de los Bovinos/parasitología , Brotes de Enfermedades/veterinaria , Rhipicephalus/parasitología , Animales , Vectores Arácnidos/parasitología , Babesia/clasificación , Bovinos , Enfermedades de los Bovinos/transmisión , Texas/epidemiología
7.
Parasitology ; 129 Suppl: S353-66, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15938518

RESUMEN

Toward the end of the nineteenth century a complex of problems related to ticks and tick-borne diseases of cattle created a demand for methods to control ticks and reduce losses of cattle. The discovery and use of arsenical solutions in dipping vats for treating cattle to protect them against ticks revolutionized tick and tick-borne disease control programmes. Arsenic dips for cattle were used for about 40 years before the evolution of resistance of ticks to the chemical, and the development and marketing of synthetic organic acaricides after World War II provided superior alternative products. Most of the major groups of organic pesticides are represented on the list of chemicals used to control ticks on cattle. Unfortunately, the successive evolution of resistance of ticks to acaricides in each chemical group with the concomitant reduction in the usefulness of a group of acaricides is a major reason for the diversity of acaricides. Whether a producer chooses a traditional method for treating cattle with an acaricide or uses a new method, he must recognize the benefits, limitations and potential problems with each application method and product. Simulation models and research were the basis of recommendations for tick control strategies advocating approaches that reduced reliance on acaricides. These recommendations for controlling ticks on cattle are in harmony with recommendations for reducing the rate of selection for acaricide resistance. There is a need to transfer knowledge about tick control and resistance mitigation strategies to cattle producers.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Resistencia a los Insecticidas , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Enfermedades por Picaduras de Garrapatas/veterinaria , Garrapatas/efectos de los fármacos , Animales , Vectores Arácnidos/efectos de los fármacos , Bovinos , Insecticidas/administración & dosificación , Infestaciones por Garrapatas/prevención & control , Enfermedades por Picaduras de Garrapatas/prevención & control
8.
Vet Parasitol ; 116(3): 251-8, 2003 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-14559168

RESUMEN

Twenty-three mixed-breed herd cows were phenotyped for their ability to serve as a suitable host for Haematobia irritans, the horn fly. Based upon consistent observations within the lower quartile or upper quartile of individual fly counts, four cows were phenotyped as low carriers and five cows were phenotyped as high carriers of horn flies. The cows designated as low carriers consistently carried levels of flies below the economic threshold. However, during a period of fly population explosion, low carriers harbored flies well above the economic threshold. Although the number of flies counted on these low carrying cattle increased as the population increased, the relative percentage of the population that they carried changed very little. A hypothesis is proposed to explain this observation, and future studies are suggested.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Infestaciones Ectoparasitarias/parasitología , Infestaciones Ectoparasitarias/veterinaria , Muscidae/crecimiento & desarrollo , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Infestaciones Ectoparasitarias/inmunología , Femenino , Inmunidad Innata/genética , Inmunidad Innata/inmunología
9.
Stud Health Technol Inform ; 96: 173-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15061541

RESUMEN

PRIDEH (Privacy Enhancement in Data Management in e-Health) is a project that runs for two years and is partly funded by the European Commission. The focus of PRIDEH is on the stimulation of the take-up of privacy enhancing technologies within the health domain. Privacy enhancing technologies build upon available cryptographic and communication technologies. The concept of privacy enhancing services delivery through the use of intermediary trusted third parties has already been described in literature but rarely turned into practice. A number of limited PET (Privacy Enhancing Technologies) applications exist in closed domains. The very few existing solutions are not based on an independent TTP (Trusted Third Party) concept which renders their trustworthiness questionable. PRIDEH wants to enhance the take-up of PET delivery based on sound TTP principles in the domain of healthcare.


Asunto(s)
Seguridad Computacional , Confidencialidad , Aplicaciones de la Informática Médica , Sistemas de Registros Médicos Computarizados , Unión Europea , Humanos , Internet , Desarrollo de Programa
10.
Insect Biochem Mol Biol ; 32(9): 1009-16, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12213237

RESUMEN

We utilized RNA Northern blot analysis and ribonuclease protection assays (RPA) to study the mRNA expression level of a putative carboxylesterase-encoding gene from several strains of Boophilus microplus (Canestrini). Both the Northern analysis and RPAs indicated that an esterase transcript was more abundant in the pyrethroid resistant strain, Coatzacoalcos (Cz), compared to a susceptible control strain and a resistant strain whose pyrethroid resistance is mediated through a target site insensitivity mechanism. A PCR-based assay was designed to identify the presence of a previously reported point mutation in this B. microplus esterase gene. The reported G-->A substitution at nucleotide 1120 creates an EcoR I site in the mutant allele which can be detected by EcoR I digestion of the amplification products. The PCR assays showed that the frequency of the mutant allele was highest in the Cz-resistant strain, which has been shown to have an esterase-mediated resistance mechanism. The PCR assay can be performed either on individual tick larvae or hemolymph from adults.


Asunto(s)
Alelos , Hidrolasas de Éster Carboxílico/genética , Piretrinas , Garrapatas/enzimología , Animales , Northern Blotting , Expresión Génica , Frecuencia de los Genes , Resistencia a los Insecticidas , Reacción en Cadena de la Polimerasa/métodos , Ribonucleasas , Garrapatas/genética
11.
Vet Parasitol ; 99(1): 41-52, 2001 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-11445154

RESUMEN

The efficacy of a single whole-body spray of spinosad, a naturally derived control agent, applied at three concentrations was evaluated against cattle infested three separate times prior to treatment and at four weekly intervals following treatment with Boophilus microplus (Canestrini). At 0.0167% active ingredient (AI) both tick numbers (1894 ticks per calf) and index of fecundity (IF) of females (258.3) were no different than that of the control group. However, spinosad treatment at both 0.05 and 0.15% AI resulted in fewer ticks per calf (600 and 935, respectively) with lower IF values for females (43.4 and 38.4, respectively). The percent control of ticks on the animals at the time of treatment (acute efficacy) was dramatically lower at 0.0167% AI (21.4%) than at 0.05 (86.3%) and 0.15% AI (87.9%). Spinosad treatments appeared to be more effective against immature stages (nymphs and larvae) than against adult ticks that were on the animals at the time of treatment. The mean weight of females that survived to repletion was similar (322-348 mg) in all groups. By contrast, the mean weight of egg masses produced by females was highest in the control group (155 mg), whereas each increase in spinosad concentration resulted in a substantial decrease in egg mass weight, with the 0.15% AI group averaging only 73 mg. The hatch rate of eggs derived from females ranged from 93.4% in control females down to 53.9% hatch for females treated at 0.15% AI spinosad. The residual efficacy of spinosad at 0.0167% AI was poor even at 1 week following treatment, resulting in 101 ticks per calf and a level of control of only 66.4%. At 0.05% AI, protection against successful reinfestation was high at 1-week post-treatment where only five ticks per calf reached repletion, and control of the IF of these females was 99.3%. The 0.15% AI treatment provided almost complete protection against reinfestation for 2 weeks following treatment (< or =5 ticks per calf), and control of the IF of these ticks was >99.9%. Thus, the use of spinosad at US ports-of-entry would be unacceptable because of the critical necessity of achieving 100% control with a single treatment to prevent the reintroduction of ticks. However, it is likely ticks could be eradicated using spinosad in tick infested areas of the US if repeated (systematic) treatments were applied to cattle maintained on the premises.


Asunto(s)
Enfermedades de los Bovinos/tratamiento farmacológico , Insecticidas/uso terapéutico , Ixodes , Macrólidos/uso terapéutico , Infestaciones por Garrapatas/veterinaria , Administración Tópica , Aerosoles , Animales , Bovinos , Combinación de Medicamentos , Femenino , Insecticidas/administración & dosificación , Macrólidos/administración & dosificación , Infestaciones por Garrapatas/tratamiento farmacológico
12.
J Med Entomol ; 38(2): 298-302, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11296838

RESUMEN

Rhipicephalus sanguineus (Latreille) were collected from the Corozal Army Veterinary Quarantine Center in Panama and characterized for resistance to five classes of acaricides. These ticks were highly resistant to permethrin, DDT, and coumaphos; moderately resistant to amitraz; and not resistant to fipronil when compared with susceptible strains. Resistance to both permethrin and DDT may result from a mutation of the sodium channel. However, synergist studies indicate that enzyme activity is involved. The LC50 estimate for permethrin was lowered further in the Panamanian strain then in susceptible strains with the addition of triphenylphosphate (TPP), but not with the addition ofpiperonyl butoxide (PBO). This suggests that esterases and not oxidases are responsible for at least some pyrethroid resistance. Elevated esterase activity and its inhibition by TPP were confirmed by native gel electrophoresis. The LC50 estimate obtained for coumaphos in the Panamanian strain was not lowered further than what was observed for susceptible strains by the addition of TPP or PBO. This indicates that enzyme activity might not be involved in coumaphos resistance. Resistance to amitraz was measured through a modification of the Food and Agriculture Organization Larval Packet Test. All tick strains were found to be susceptible to fipronil.


Asunto(s)
Insecticidas , Control de Ácaros y Garrapatas , Infestaciones por Garrapatas/veterinaria , Garrapatas , Animales , Bioensayo , Electroforesis/métodos , Femenino , Resistencia a los Insecticidas , Panamá , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/parasitología
13.
Proc AMIA Symp ; : 771-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11825290

RESUMEN

The Rapid Syndrome Validation Project (RSVP) is a collaboration of several institutions: Sandia and Los Alamos National Laboratories, the University of New Mexico Department of Emergency Medicine, and the NM Department of Health Office of Epidemiology. RSVP is a system that operates at the intersection of individual health care providers, public health and bioterrorism. Physicians quickly enter clinical and demographic information on patients exhibiting symptoms and signs of the syndromes of interest. It provides early warning and response to emerging biological threats, as well as emerging epidemics and diseases. RSVP provides real time clinical information to the provider and any other potential user such as the DOH, about current symptoms, disease prevalence and location. The system also serves as a mechanism for the Department of Health to inform health care providers of health alerts and to facilitate the process of collecting data on reportable diseases. We describe here the purpose an the architecture of a network-based surveillance system that is currently implemented in an Emergency Department.


Asunto(s)
Brotes de Enfermedades , Sistemas de Información , Vigilancia de la Población/métodos , Bioterrorismo , Redes de Comunicación de Computadores , Sistemas de Computación , Servicio de Urgencia en Hospital , Agencias Gubernamentales , Personal de Salud , Humanos , Administración en Salud Pública , Programas Informáticos , Síndrome , Estados Unidos
14.
J Econ Entomol ; 94(6): 1622-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11777074

RESUMEN

When Hereford heifers infested with Boophilus annulatus (Say) were treated with a single Ivomec SR Bolus, the concentration of ivermectin in the serum of the treated cattle reached a maximum of 8.8 +/- 0.9 ppb at 2 wk posttreatment. The single bolus treatment resulted in 84.4% control of standard engorging B. annulatus females on treated cattle over the 20-wk trial. Although fewer engorged ticks were collected from the sentinel heifers exposed in the treated pasture than those in the control pasture at weeks 4, 10, and 16 posttreatment, none of the differences was statistically significant. Each exposure of sentinel cattle found free-living ticks in both the treated and control pastures, indicating the infestation was not eliminated by the treatment. When the trial was repeated using two Ivomec SR Boluses/heifer, the concentration of ivermectin in the serum of the treated cattle reached a maximum level of 31.2 +/- 3.9 ppb at week 13 posttreatment. The use of two boluses/heifer resulted in 99.6% control of standard engorging B. annulatus females over the 20-wk trial. No ticks were found on sentinels placed in the treated pasture after week 9 posttreatment, an indication that the treatment had eliminated the free-living population in the treated pasture. From these studies, we conclude that a single Ivomec SR Bolus is incapable of sufficient control of B. annulatus to meet the rigid requirements of the Cattle Fever Tick Eradication Program in South Texas. Although two boluses per animal did eliminate the ticks from treated heifers and the pasture they were in, the treatment would not be sufficiently efficacious for mature cattle (>400 kg) for it to be useful in the program.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Insecticidas , Ivermectina , Ixodidae , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Femenino , Densidad de Población , Texas , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/prevención & control
15.
J Med Entomol ; 37(6): 878-84, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11126544

RESUMEN

White-tailed deer treated themselves with a commercial pour-on acaricide formulation containing 2% amitraz as they fed from an ARS-patented '4-poster' topical treatment device. Whole kernel corn attracted deer to a single device placed in each of two deer-fenced pastures. In the treatment pasture, the rollers of the treatment device were charged with the acaricide, whereas the rollers of the device in the other pasture remained untreated. Deer were allowed to use the '4-posters' during periods of tick activity beginning in early to midspring and lasting through late summer to early fall for three consecutive years. Pretreatment sampling of adults and nymphs with dry-ice traps and larval masses with flip cloths showed no significant differences in population indices between the two pastures; however, after the third year of treatment, control of nymphal and adult ticks in the treated pasture was 91.9 and 93.7%, respectively, when compared with the untreated pasture. Control of larval masses increased from 68.4% in year 1 to 96.4% in year 2, but declined to 88.0% in year 3, probably because of the presence of feral hogs. This study demonstrated that application of amitraz to white-tailed deer through free-choice interaction with a '4-poster' device significantly reduced the abundance of free-living lone star ticks in a deer-fenced experimental pasture. Moreover, the yearly pattern of incremental increases in control and the final percentage control values for all three parasitic life stages in this topical application study were similar in magnitude to that observed in a previously conducted study in which the systemic acaricide ivermectin was used to reduce populations of free-living ticks by controlling ticks on deer.


Asunto(s)
Insecticidas , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Garrapatas , Toluidinas , Animales , Ciervos , Infestaciones por Garrapatas/prevención & control
16.
J Med Entomol ; 37(4): 588-94, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10916301

RESUMEN

A '4-poster' device that attracts white-tailed deer to a bait source, and as they feed, allows a self-application of a pesticide to the head, ears, and neck to control ticks was designed, constructed, and tested. The device consists of a central bin containing bait to attract deer and two feeding and application stations. These stations each have one bait port and two vertical pesticide-impregnated applicator rollers. This design allows unrestricted vertical retraction of the head to minimize injury to the deer or damage to the posts supporting the pesticide application rollers. Observations using deer demonstrated ready acceptance and repeated use by both antlered and antlerless deer. Results of an initial trial indicate that control values for lone star ticks, Amblyomma americanum (L.), exceeded 92-97% on deer that used the device regularly.


Asunto(s)
Ciervos/parasitología , Insecticidas , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Garrapatas , Animales , Conducta Alimentaria , Infestaciones por Garrapatas/prevención & control
17.
Insect Biochem Mol Biol ; 30(10): 969-77, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10899463

RESUMEN

Two esterase cDNA sequences were obtained from susceptible and organophosphorus resistant strains of Boophilus microplus. Both sequences have a high degree of homology to carboxylesterase B. One gene has identical sequences in both strains and the other showed two point mutations. One mutation produces an amino acid substitution when the amino acid sequence is deduced, this mutation was detected in six different populations susceptible and resistant to insecticides, but a pyrethroid resistant strain was the only one that showed only the mutant allele. Identification of this mutation and the strong signal detected in southern blot with this strain, suggest that esterases are contributing to detoxification of pyrethroid compounds, as a resistant mechanism in Mexican strains of the southern cattle tick.


Asunto(s)
Esterasas/genética , Mutación Puntual , Garrapatas/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , ADN Complementario , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Garrapatas/genética
18.
Ann N Y Acad Sci ; 916: 583-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11193677

RESUMEN

Arsenic dips were the first effective method for controlling ticks and tick-borne diseases, and were used in many parts of the world for over 50 years before resistance to the chemical became a problem. Until organochlorine products became available about 1946 as alternatives to arsenic, significant losses occurred in cattle herds exposed to arsenic-resistant tick strains. Since the discovery of organochlorines, virtually every chemical group of pesticides developed for the control of arthropods is represented among the list of products employed for the control of ticks on cattle. The evolution of tick resistance to acaricides has been a major determinant of the need for new products. The variety of procedures for treating animals with acaricides ranges from dipping cattle to injecting systemic acaricides, but regardless of the treatment method used, producers need to know and follow proper application procedures to derive maximum benefits. The possibility of stocking with cattle breeds that acquire pronounced resistance to ticks or using recombinant antigen antitick vaccines are the most promising alternatives to acaricides. Most ranchers depend completely on acaricides to control ticks, but do not have access to guidelines on how to make a profit from their tick control program or how to detect and resolve problems with resistance to acaricides. Extension programs are needed to help ranchers manage animal health problems, including how to control ticks and tick-borne diseases.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Garrapatas , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Insecticidas , Control de Ácaros y Garrapatas/tendencias , Infestaciones por Garrapatas/prevención & control
19.
J Med Entomol ; 37(1): 1-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15218899

RESUMEN

A variety of pathways exist for the introduction of nonindigenous insects, ticks, and mites of veterinary importance into the United States. The most prominent includes the natural migration of mosquitoes and flies by the flight of adults, ectoparasites entering the country on wildlife transport hosts, and accidental introductions on animals legally imported through United States Department of Agriculture (USDA) quarantine facilities. Examples of the establishment and subsequent eradication of exotic pests of livestock are presented to illustrate the critical role of the USDA in protecting American agriculture with particular emphasis on the southern cattle tick, Boophilus microplus (Canestrini), the cattle tick, B. annulatus (Say), and the screwworm, Cochliomyia hominivorax (Coquerel). Priority group rating of nonindigenous arthropod pests and disease vectors are discussed. Although the primary responsibility for preventing the introduction and establishment of arthropods that affect livestock and poultry rests on the shoulders of USDA professionals, insect surveys by extension entomologists along with observations by research specialists and producers are also important in detecting exotic arthropod species. Animal health professionals from all sectors of the livestock and poultry industries may well be the first line of defense from the introduction of nonindigenous arthropods and the diseases they transmit.


Asunto(s)
Enfermedades de los Animales/parasitología , Artrópodos/patogenicidad , Animales , Enfermedades de las Aves/parasitología , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/prevención & control , Dípteros , Infestaciones por Garrapatas/prevención & control , Infestaciones por Garrapatas/veterinaria
20.
J Econ Entomol ; 92(5): 1142-6, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10582049

RESUMEN

The efficacy of an injectable microsphere formulation of ivermectin for control of the cattle tick, Boophilus annulatus (Say), was tested on 2 groups of 6 Hereford heifers held on separate 7-ha, tick-infested, buffel grass pastures. Cattle in one pasture were injected subcutaneously in the neck with a controlled-release microsphere formulation of ivermectin at the rate of 2.4 mg AI/kg body weight; the other group was injected with carrier only. Beginning 4 wk after injection and continuing throughout the remainder of the test (16 wk), no engorged ticks (> or = 5.5 mm) were found on any of the treated cattle, whereas large numbers of engorged ticks were found on the untreated controls. During this period, a few ticks were recovered from untreated sentinel animals placed in the treatment pasture during 7-8 wk after treatment, but none were recovered from animals exposed from 11-12 wk or 14-15 wk. Large numbers of B. annulatus ticks were found on untreated sentinel cattle placed in the control pasture during these same periods. Although the cattle, pastures, and tick habitat were approximately equal, the treated cattle gained an average of 77 kg compared with an average of 42 kg for the control group. This technology offers a possible alternative to the current official program of dipping and vacating pastures for eradication of Boophilus sp. infestations from the quarantine zone in southern Texas. Larger scale testing is needed to determine the potential of the injectable microsphere formulation and to optimize its use in eradication or control strategies.


Asunto(s)
Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/parasitología , Insecticidas/uso terapéutico , Ivermectina/uso terapéutico , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Análisis de Varianza , Animales , Bovinos , Enfermedades de los Bovinos/sangre , Conducta Alimentaria , Femenino , Interacciones Huésped-Parásitos , Inyecciones Subcutáneas , Ivermectina/sangre , Microesferas , Infestaciones por Garrapatas/parasitología , Garrapatas/fisiología
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